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Journal articles on the topic 'Polymer microbeads'

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Author: Grafiati

Published: 10 December 2022

Last updated: 29 January 2023

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1

Okunlola, Adenike, and Shukuralilahi Abidemi Adewusi. "Development of Theophylline Microbeads Using PregelatinizedBreadfruit Starch (Artocarpus altilis) as a Novel Co-polymer for Controlled Release." Advanced Pharmaceutical Bulletin 9, no. 1 (February 21, 2019): 93–101. http://dx.doi.org/10.15171/apb.2019.012.

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Purpose: The aim of this study was to prepare formulations of theophylline microbeads usingpregelatinized breadfruit starch (Artocarpus altilis, family Moraceae) in combination withsodium alginate and chitosan at various polymer: drug ratios. Microbead formulations forcontrolled delivery of theophylline would be better alternatives to conventional dosage formsfor optimized drug therapy.Methods: The native and pregelatinized starches were characterized for morphology (scanningelectron microscope), crystallinity (Fourier transform intra-red spectroscopy, FTIR and X-raydiffractometer, XRD), thermal flow (differential scanning colorimeter), density and flowproperties. Theophylline microbeads were prepared by ionic gelation and characterized usingsize, swelling index, entrapment efficiency and time required for 15% and 50% drug release (t15and t50 respectively).Results: FTIR and XRD spectra revealed the orderly arrangement of granules of the semi-crystallinebreadfruit starch was disrupted on gelatinization. The viscosity and flow of pregelatinized starchwere enhanced. Theophylline microbeads were near spherical in shape with size range 1.09± 0.672 to 1.58 ± 0.54 mm. FTIR and XRD spectra confirmed there was no drug-polymerinteraction. Microsphere size, swelling increased while entrapment and dissolution time (t50)reduced with polymer: drug ratio. The entrapment efficiency ranged from 30.99 ± 1.32 to 78.50± 2.37%. Optimized formulation, starch: alginate ratio 3:1 at polymer: drug ratio of 2:1, gave aprolonged dissolution time (t50 = 8.40 ± 1.20 h).Conclusion: Breadfruit starch was suitable as a copolymer for the controlled delivery oftheophylline in microbeads which could serve as a substitute to synthetic polymers in drugdelivery.

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2

Větvička, Václav, and Lubor Fornůsek. "Polymer microbeads in immunology." Biomaterials 8, no. 5 (September 1987): 341–45. http://dx.doi.org/10.1016/0142-9612(87)90003-2.

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3

Okunlola, A., and S. T. Oloye. "Influence of Pregelatinized Breadfruit Starch-Alginate Blend as a Sustained Release Polymer in Theophylline Microbeads Using Box Behnken Design." Nigerian Journal of Pharmaceutical Research 16, no. 2 (January 19, 2021): 143–51. http://dx.doi.org/10.4314/njpr.v16i2.5.

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Background: Apart from the coating property of modified starches on drugs, these natural polymers also acts as release rate retardants.Objectives: To evaluate the potential of pregelatinized breadfruit (Artocarpus altilis) starch as a carrier in microbead formulations of theophylline using different blend combinations with sodium alginate and to determine the optimized formulation using Box-Behnken design.Method: Theophylline microbeads were prepared using the ionic gelation method. The 3 factor-3 level Box-Behnken design was employed for constructing polynomial models to optimize the microbeads, involving 3 independent variables (polymer type, X1, polymer: drug ratio, X2, and concentration of calcium chloride, X3) and 2 dependent variable (entrapment efficiency and quantity of drug released in 12 h, Q12).Results: Entrapment efficiency was 35 - 71 % while the values of Q12 was 38 - 88 %. The three variables, X1, X2 and X3, were positive for entrapment efficiency but negative for Q12, implying that increase from low to medium and then to high level resulted in an increase in entrapment but a decrease in Q12 (sustained release), both desirable effects. Factor X1 had the most significant influence on entrapment efficiency and Q12 (p = 0.002; p = 0.0001, respectively). The optimized formulation with starch:polymer 2:1, polymer:drug 3:1 and 7.5%w/v calcium chloride solution gave an entrapment efficiency 65% with Q12 of 38.75%.Conclusion: Pregelatinized breadfruit starch enhanced entrapment efficiency while retarding drug release, showing its potential as a polymer for sustained release in microbead formulations. Keywords: Box-Behnken design; Breadfruit starch; Ionic gelation, Microbeads, Pregelatinization

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4

Debasis Nayak and Saravanan Kaliyaperumal. "Development and effect of drug release from simvastatin loaded sodium alginate micro beads." World Journal of Biology Pharmacy and Health Sciences 12, no. 3 (December 30, 2022): 348–58. http://dx.doi.org/10.30574/wjbphs.2022.12.3.0259.

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The objective of the present study was to prepare the microbeads of Simvastatin loaded with sodium alginate to provide control release of drug delivery system. So, the design of drug delivery system was to improve and enhance the bioavailability of drug. The Simvastatin loaded microbeads were prepared by the ionic gelation method using polymer such as sodium alginate as a natural substance. Simvastatin loaded sodium alginate microbeads were formulated by different cross linking agent like CaCl₂, BaCl₂, ZnCl₂ and FeCl₃ in different ratio. The microbeads were spherical, free flowing exhibited drug content uniformity and high drug encapsulation efficiency. The swelling and drug release behavior depends upon amount of cross linking agent used in the microbeads. This released the drug up to 24 hours where beads released the drug up to 6 hours. The FTIR analysis of drug, polymers and the optimized formulation indicated the compatibility of the drug with the polymers. The DSC studies confirmed the drug polymer interaction in the microspheres. The SEM studies influence the rate of drug release from the microbeads. The present study concludes that the swelling and In-vitro release behavior of Simvastatin loaded sodium alginate microbeads can be considered as a promising control release drug delivery system.

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Nedovic, Viktor, Verica Manojlovic, Ulf Pruesse, Branko Bugarski, Jasna Djonlagic, and Klaus Vorlop. "Optimization of the electrostatic droplet generation process for controlled microbead production: Single nozzle system." Chemical Industry and Chemical Engineering Quarterly 12, no. 1 (2006): 53–57. http://dx.doi.org/10.2298/ciceq0601053n.

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The aim of this study was to optimize the electrostatic extrusion process for producing small, spherical and uniform microbeads with different fluid viscosities by varying the operating parameters in very wide ranges. Alginate was used as a model polymer. Since the rheological behavior of the solution is one of the parameters that affects the flow dynamics during extrusion, viscosity measurements of solutions with different alginate content were performed. The results obtained in this study show that an electrostatic droplet generator can be used for the production of spherical microbeads of narrow size distribution from low- and medium- viscous fluids (0.5, 1, and 2% of alginate). The average microbead diameter for low-viscous solutions was less than 100 micrometers. It was possible to obtain beads smaller than 500 micrometers that were very uniform (standard deviations less than 2.5%) and of spherical (the shape distortion was less than 1%) from medium-viscous alginate solution (2%). By reducing the polymer flowrate to less than 1 ml/h, even smaller microbeads were produced with diameters of about 300 micrometers. The particular contribution of this paper is in exceeding limitations regarding the use of high-viscous polymer solutions. Optimization of the operating conditions that included the use of a very small needle (0.15 mm), enlargement of the electrode distance to more than 20 cm and a severe reduction in the polymer flow rate to lower than 5 ml/h (for 3% alginate) or 1 ml/h (for 4% alginate) enabled the production of small, entirely spherical and uniform microbeads with an average microbead diameter lower than 500 and 700 micrometers in the case of 3 and 4% of alginate, respectively.

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6

Ren, Zhi Min, Xi Nie, and Sheng Shu Ai. "Influence of Blocking Agents on Non-Specific Background of Polystyrene Microbeads in Serum Immunoassay." Advanced Materials Research 641-642 (January 2013): 858–61. http://dx.doi.org/10.4028/www.scientific.net/amr.641-642.858.

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In this paper, we used bovine serum albumin and polymer as the blocking agents and investigated the effect of blocking agents on non-specific background of polystyrene microbead that used the human serum immunoassay.The results showed that the nonspecific background is lower by using polymer blocking agents. The best blocking condition was that microbeads were blocked by PVXT (0.5% polyvinyl alcohol PVA, 0.8% polyvinylpyrrolidone, 0.05% Tween-20, PBS phosphate buffer, pH7.0) for two hours at room temperature.

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7

Foti, Leonardo, Andre Sionek, Elis Moura Stori, Paula Poli Soares, Miriam Marzall Pereira, Marco Aurélio Krieger, Cesar Liberato Petzhold, et al. "Electrospray induced surface activation of polystyrene microbeads for diagnostic applications." Journal of Materials Chemistry B 3, no. 13 (2015): 2725–31. http://dx.doi.org/10.1039/c4tb01884b.

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Proposed electrochemical reaction mechanism: (a) highly charged microbeads approach the electrolyte; (b) microbeads sink and are solvated by water molecules; (c) water oxidation reaction disrupts PS surface bonds; (d) oxygen is incorporated into the polymer chains.

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8

Dahima, Rashmi. "Formulation and Evaluation of Pseudoephedrine Hydrochloride Loaded Alginate Microbeads." Journal of Drug Delivery and Therapeutics 10, no. 3 (May 15, 2020): 137–41. http://dx.doi.org/10.22270/jddt.v10i3.4094.

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Multiple unit dosage forms such as microbeads have increased acceptance because of added even spreading of the drug in the gastrointestinal tract, unvarying drug absorption, abridged local irritation and removal of undesirable intestinal retaining of polymeric material, when compared to non-disintegrating single unit dosage form. The purpose of the presented research is to develop microbeads of pseudoephedrine hydrochloride utilizing sodium alginate as the hydrophilic carrier in combination with HPMC as drug release modifier to lessen the dosing frequency and thereby advance the patient compliance. The microbeads were formulated by varying concentrations of HPMC and calcium chloride. The optimum formulation was chosen based upon in vitro drug release studies and further evaluated. The compatibility of drug-polymer was studied using FTIR analysis. The prepared formulation underwent evaluation for various parameters like drug entrapment, microbeads size, swelling index, mucoadhesive property and stability. No significant drug-polymer interactions were observed in compatibility studies and the formulation was found to be stable on 45 days storage. The formulations exhibited an extended drug release pattern which was the ultimate aim of the study. The microbeads represented good yield, high drug entrapment, low microbeads size and appropriate swelling property. The in vitro wash-off test indicated that the sodium alginate microbeads represent decent mucoadhesive properties. Henceforth, the formulated HPMC coated sodium alginate beads can be utilized as a substitute and cost-effective carrier for the oral controlled delivery of pseudoephedrine hydrochloride. Keywords: microbeads, pseudoephedrine hydrochloride, sodium alginate, drug release

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9

Kage, Daniel, Linn Fischer, Katrin Hoffmann, Thomas Thiele, Uwe Schedler, and Ute Resch-Genger. "Close Spectroscopic Look at Dye-Stained Polymer Microbeads." Journal of Physical Chemistry C 122, no. 24 (June 8, 2018): 12782–91. http://dx.doi.org/10.1021/acs.jpcc.8b02546.

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10

Liu, Yixi, Le Liu, Yonghong He, Qinghua He, and Hui Ma. "Quantum-dots-encoded-microbeads based molecularly imprinted polymer." Biosensors and Bioelectronics 77 (March 2016): 886–93. http://dx.doi.org/10.1016/j.bios.2015.10.024.

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11

Fhong Soon, Chin, Soon Chuan Wong, Wai Yean Leong, Mohd Khairul Ahamd, and Kian Sek Tee. "A flicking method for generation of polymer microbeads." JJAP Conference Proceedings 4 (2016): 011110. http://dx.doi.org/10.56646/jjapcp.4.0_011110.

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12

Khan, Ikram Ullah, Mehwish Shoukat, Muhammad Asif, Syed Haroon Khalid, Sajid Asghar, Muhammad Usman Munir, Muhammad Irfan, et al. "Assessing the Synergistic Activity of Clarithromycin and Therapeutic Oils Encapsulated in Sodium Alginate Based Floating Microbeads." Microorganisms 10, no. 6 (June 7, 2022): 1171. http://dx.doi.org/10.3390/microorganisms10061171.

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We developed alginate-based floating microbeads of clarithromycin with therapeutic oils for the possible eradication of Helicobacter pylori (H. pylori) infections by enhancing the residence time of the carrier at the site of infection. In pursuit of this endeavor, the alginate was blended with hydroxy propyl methyl cellulose (HPMC) as an interpenetrating polymer to develop beads by ionotropic gelation using calcium carbonate as a gas generating agent. The developed microbeads remained buoyant under gastric conditions for 24 h. These microbeads initially swelled and afterwards decreased in size, possibly due to the erosion of the polymer. Furthermore, swelling was also affected by the type of encapsulated oil, i.e., swelling decreased with increasing concentrations of eucalyptus oil and increased with increasing concentrations of oleic acid. Antibacterial assays of the formulations showed significant antibacterial activity against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli); these assays also showed synergistic activity between clarithromycin and therapeutic oils as evident from the higher zone of inhibition of the microbeads as compared to the pure drug and oils. Scanning electron microscopy (SEM) images revealed a smoother surface for oleic acid containing the formulation as compared to eucalyptus oil containing the formulation. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) revealed the development of a stable formulation, while Fourier transform infrared spectrophotometry (FTIR) studies did not reveal any interaction between the polymers and the active ingredients. Optimized formulations (CLM3 and CLM6) were designed to release the drug in a controlled manner in gastric media by Fickian diffusion. Conclusively, the developed microbeads are a promising carrier to overcome the narrow therapeutic index and low bioavailability of clarithromycin, while the presence of therapeutic oils will produce synergistic effects with the drug to eradicate infection effectively.

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13

Shibuya, Masachika, Tatsuhiro Takahashi, and Kiyohito Koyama. "Microcellular ceramics by using silicone preceramic polymer and PMMA polymer sacrificial microbeads." Composites Science and Technology 67, no. 1 (January 2007): 119–24. http://dx.doi.org/10.1016/j.compscitech.2006.03.022.

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14

Branger and Brisset. "Advanced Electrochemical Molecularly Imprinted Polymer as Sensor Interfaces." Proceedings 15, no. 1 (July 12, 2019): 22. http://dx.doi.org/10.3390/proceedings2019015022.

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Electrochemical molecularly imprinted polymers (e-MIP) are MIP specially designed to detect aromatic organic molecules without redox properties. The detection is based on the electrochemical answer of a redox probe inserted inside the binding cavities of cross-linked MIPs. Microbeads of e-MIP were synthesized from vinylferrocene or ferrocenylmethyl methacrylate as functional monomer/redox probe with or without 4-vinylpyridine functional as co-monomer, benzo[a]pyrene or bisphenol A as the target and ethylene glycol dimethacrylate of divinylbenzene as cross-linker. After physico-chemical characterization, e-MIP microbeads were incorporated in a graphite paste to prepare modified electrode or screen-printed carbon electrodes (SPCE).

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15

Say, Rıdvan, Ebru Birlik, Arzu Ersöz, Filiz Yılmaz, Tevfik Gedikbey, and Adil Denizli. "Preconcentration of copper on ion-selective imprinted polymer microbeads." Analytica Chimica Acta 480, no. 2 (March 2003): 251–58. http://dx.doi.org/10.1016/s0003-2670(02)01656-2.

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16

Duckworth, John, Takaaki Arahira, and Mitsugu Todo. "Fracture characterization of novel bioceramic microbeads filled polymer composite." Journal of Materials Science 55, no. 21 (April 16, 2020): 8954–67. http://dx.doi.org/10.1007/s10853-020-04656-w.

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17

Amsden, Brian G. "Osmotically activated agent release from electrostatically generated polymer microbeads." AIChE Journal 42, no. 11 (November 1996): 3253–66. http://dx.doi.org/10.1002/aic.690421126.

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18

Masoomi, Hajar, Yao Wang, Cang Chen, Jiayu Zhang, Yunfei Ge, Qingsheng Guo, Hongchen Gu, and Hong Xu. "A facile polymer mediated dye incorporation method for fluorescence encoded microbeads with large encoding capacities." Chemical Communications 57, no. 37 (2021): 4548–51. http://dx.doi.org/10.1039/d0cc08202c.

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19

Haleem, Kainat, Safiullah Khan, Shahzada Khurram Syed, and Saif Ur Rehman. "Development of gastro retentive microbeads for sustained release of fexofenadine and montelukast." Journal of Contemporary Pharmacy 5, no. 1 (July 31, 2021): 16–27. http://dx.doi.org/10.56770/jcp2021513.

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In allergic rhinitis, montelukast (leukotriene receptor antagonist) in combination with fexofenadine (antihistamine) provide improved and complimentary effects and reduce the allergic symptoms effectively. Montelukast has less bioavailability due to hepatic first pass metabolism and fexofenadine have low permeability. So sustained release delivery is crucial for these drugs. One of the techniques to overcome this challenge is the development of polymeric microspheres or microbeads for enhanced bioavailability and prolong the action of drug in body. The objective of the study is to produce a potential microencapsulated formulation having the combination of fexofenadine hydrochloride and montelukast sodium. Microbeads were formulated by using polymer, eudragit RS100. Single emulsion solvent evaporation method was used for the preparation of formulation. The developed drug loaded polymeric microbeads showed that percentage floating ranged from 82.1 - 90.4%. Entrapment efficiency of microbeads were found between 68.8- 80.9%. FTIR results revealed absence of drug-polymer interaction. In-vitro release studies shown that from all the prepared formulations of both drugs the optimum formulation was released up to 24hrs and percentage cumulative drug release was 87.40% and 89.78% respectively. The acute toxicity study showed the safety of the developed system. Formulated microbeads were significantly efficient to achieve a sustained release of fexofenadine and montelukast with prolonged therapeutics release up to 24 hours. The developed gastro retentive floating drug delivery systems showed excellent physicochemical properties and sustained drug release pattern, thereby improving the bioavailability of the drugs.

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20

Tristantini, Dewi, and Andersen Yunan. "Advanced characterization of microbeads replacement from cellulose acetate based on empty fruit bunches and dried jackfruit leaves." E3S Web of Conferences 67 (2018): 04045. http://dx.doi.org/10.1051/e3sconf/20186704045.

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The existing polymer microbeads for skin extraction ingredients have many disadvantages in environment. The application of cellulose has been proven in the pharmaceutical field in the form of beads on drug release can be a substitute alternative to polymer microbeads that will be prohibited. Based on several criteria and past researches, cellulose acetate meets the criteria for microbeads replacement. Cellulose is available in large quantities in the world, and many studies has proven its application on a wide scope. Empty Fruit Bunches (EFB) and Dried Jackfruit Leaves (DJL) are widely distributed raw materials in Indonesia so that they can be used as a substitute for microbeads. The FTIR and SEM-EDX tests were conducted to determine the functional groups of cellulose acetate and morphology formation of cellulose acetate both raw materials and their chemical composition. In FTIR testing, the typical absorption of EFB and DJL cellulose acetate is produced by C=O groups for EFB at wavelength 1721,36 cm-1 and DJL at wavelength 1725,22 cm-1, whereas at SEM-EDX, DJL cellulose acetate asymmetrical cylinders and rare small pores on the surface and cellulose acetate TKKS cylindrical symmetrical with small pores on its surface. The chemical components of EFB and DJL cellulose acetate exhibit organic elements of carbon (C) and oxygen (O).

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21

Kage, Daniel, Linn Fischer, Katrin Hoffmann, Thomas Thiele, Uwe Schedler, and Ute Resch-Genger. "Correction to “Close Spectroscopic Look at Dye-Stained Polymer Microbeads”." Journal of Physical Chemistry C 123, no. 26 (June 20, 2019): 16494. http://dx.doi.org/10.1021/acs.jpcc.9b05365.

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22

Kim, Ha Yeong, Ji Min Seok, Soo Yeon Jung, Min Ji Lee, An Nguyen-Thuy Tran, Seon Ju Yeo, Su A. Park, and Han Su Kim. "Development of Surgically Transplantable Parathyroid Hormone-Releasing Microbeads." Biomedicines 10, no. 2 (February 14, 2022): 440. http://dx.doi.org/10.3390/biomedicines10020440.

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Hypoparathyroidism is an endocrine disorder that occurs because of the inability to produce parathyroid hormone (PTH) effectively. Previously, we reported the efficacy of tonsil-derived mesenchymal stem cells (TMSCs) differentiated into parathyroid-like cells for the treatment of hypoparathyroidism. Here, we investigated the feasibility of three-dimensional structural microbeads fabricated with TMSCs and alginate, a natural biodegradable polymer, to treat hypoparathyroidism. Alginate microbeads were fabricated by dropping a 2% (w/v) alginate solution containing TMSCs into a 5% CaCl2 solution and then differentiated into parathyroid-like cells using activin A and sonic hedgehog for 7 days. The protein expression of PTH, a specific marker of the parathyroid gland, was significantly higher in differentiated alginate microbeads with TMSCs (Al-dT) compared with in undifferentiated alginate microbeads with TMSCs. For in vivo experiments, we created the hypoparathyroidism animal model by parathyroidectomy (PTX) and implanted alginate microbeads in the dorsal interscapular region. The PTX rats with Al-dT (PTX+Al-dT) showed the highest survival rate and weight change and a gradual increase in serum intact PTH levels. We also detected a higher expression of PTH in retrieved tissues of PTX+Al-dT using immunofluorescence analysis. This study demonstrates that alginate microbeads are potential a new tool as a surgically scalable therapy for treating hypoparathyroidism.

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23

Liu, Z. L., Z. H. Ding, K. L. Yao, J. Tao, G. H. Du, Q. H. Lu, X. Wang, F. L. Gong, and X. Chen. "Preparation and characterization of polymer-coated core–shell structured magnetic microbeads." Journal of Magnetism and Magnetic Materials 265, no. 1 (September 2003): 98–105. http://dx.doi.org/10.1016/s0304-8853(03)00230-0.

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24

Muhammad Imran, Syed, Yoong Ahm Kim, Yong-Ho Choa, Manwar Hussain, and Kap Seung Yang. "Pressure-sensitive polymer nanocomposites: Carbon nanofiber-reinforced MWCNT-coated PMMA microbeads." Polymer-Plastics Technology and Materials 58, no. 16 (February 11, 2019): 1793–801. http://dx.doi.org/10.1080/25740881.2019.1576198.

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25

Tristantini, Dewi, and Andersen Yunan. "Characterization of cellulose acetate based on empty fruit bunches and dried jackfruit leaves as replacement candidates for microbeads." E3S Web of Conferences 67 (2018): 04024. http://dx.doi.org/10.1051/e3sconf/20186704024.

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Scrubs used in other skin care and beauty products usually contain tiny fine grains of synthetic polymer called microbeads that usually pose threats to marine environment. Empty Fruit Bunches (EFB) and Dried Jackfruit Leaves (DJL) as organic and environmentally friendly can be alternative sources for polymer microbeads. Cellulose acetate is prepared by acetylation reaction between cellulose and acetic acid anhydride. Cellulose from EFB and DJL was extracted through a process of delignification with 12% NaOH treatment for EFB and 10% for DJL to obtain maximum yields of 38.964% and 14.449% respectively, followed by bleaching using peroxide 10 %. The formed cellulose acetate with 88.5% and 79.7% yield respectively is then filtered using a sieve mash 60 and 80 to obtain particle sizes ranging that are in the microbeads size range. The density test resulting in 0.73 g/cm3 and 0.52 g/cm3 respectively for EFB and DJL. Then, physical characteristic test was done by water and oil absorption test with variation at 25°C and 40°C. EFB at 25°C and 40°C shows water absorption at 23.39% and 26.09% and oil absorption at 7.59% and 13.95%. DJL at 25°C and 40°C shows water absorption at 22.56% and 27.32% and oil absorption at 13.09% and 15.36%.

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Arpa, Ç., A. Sağlam, S. Bektał, S. Patir, Ö. Genç, and A. Denizli. "Adsorption of Mercury(II) Ions by Poly(Hydroxyethylmethacrylate) Adsorbents with Thiazolidine Groups." Adsorption Science & Technology 20, no. 3 (April 2002): 203–13. http://dx.doi.org/10.1260/026361702760254405.

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A wide variety of adsorbents has been reported in the literature for heavy metal adsorption. We have recently developed a new polymer system for the removal of contaminant heavy metal ions from aquatic systems. Thus, poly(hydroxyethylmethacrylate) (PHEMA) microbeads carrying thiazolidine (0.318 mmol/g) were prepared for the removal of different amounts of mercury(II) ions (50–900 mg/l) from aqueous solutions and at different pH values (3.0–7.0). Adsorption rates were high with adsorption equilibria being reached within 10 min. The adsorption of Hg(II) ions on to the thiazolidine-immobilized microbeads from single solutions amounted to 1.11 mmol/g. The formation constant of the thiazolidine–metal ion complex was investigated by the method of Ružić. The calculated value of the stability constant was 9.11 × 105 l/mol for the Hg(II)–thiazolidine complex. PHEMA microbeads carrying thiazolidine may be regenerated by washing with a solution of hydrochloric acid (0.05 M). The maximum desorption ratio was as high as 99%. These PHEMA microbeads may be used repeatedly for more than three adsorption/desorption cycles without any considerable loss in adsorption capacity.

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Kupikowska-Stobba, Barbara, and Dorota Lewińska. "Polymer microcapsules and microbeads as cell carriers for in vivo biomedical applications." Biomaterials Science 8, no. 6 (2020): 1536–74. http://dx.doi.org/10.1039/c9bm01337g.

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This Review discusses the polymer cell microcarriers for in vivo biomedical applications, focusing on the materials and methods employed in their fabrication and their use as cell delivery vehicles for cell therapies, tissue regeneration and bioartificial organ engineering.

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Xu, Ge, Xiaojing Fan, Xirui Chen, Zilong Liu, Guoxin Chen, Xiaxia Wei, Xiangmin Li, Yuankui Leng, Yonghua Xiong, and Xiaolin Huang. "Ultrasensitive Lateral Flow Immunoassay for Fumonisin B1 Detection Using Highly Luminescent Aggregation-Induced Emission Microbeads." Toxins 15, no. 1 (January 16, 2023): 79. http://dx.doi.org/10.3390/toxins15010079.

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Lateral flow immunoassay (LFIA) based on fluorescent microbeads has attracted much attention for its use in rapid and accurate food safety monitoring. However, conventional fluorescent microbeads are limited by the aggregation-caused quenching effect of the loaded fluorophores, thus resulting in low signal intensity and insufficient sensitivity of fluorescent LFIA. In this study, a green-emitting fluorophore with an aggregation-induced emission (AIE) characteristic was encapsulated in polymer nanoparticles via an emulsification technique to form ultrabright fluorescent microbeads (denoted as AIEMBs). The prepared AIEMBs were then applied in a competitive LFIA (AIE-LFIA) as signal reporters for the rapid and highly sensitive screening of fumonisin B1 (FB1) in real corn samples. High sensitivity with a detection limit of 0.024 ng/mL for FB1 was achieved by the developed AIE-LFIA. Excellent selectivity, good accuracy, and high reliability of the AIE-LFIA were demonstrated, indicating a promising platform for FB1 screening.

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Suzuki, Ryo, Yasuo Yoshioka, Etsuko Kitano, Tatsunobu Yoshioka, Hiroaki Oka, Takayuki Okamoto, Naoki Okada, et al. "Development of a Novel Cytomedical Treatment that can Protect Entrapped Cells from Host Humoral Immunity." Cell Transplantation 11, no. 8 (November 2002): 787–97. http://dx.doi.org/10.3727/000000002783985305.

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Cell therapy is expected to relieve the shortage of donors needed for organ transplantation. When patients are treated with allogeneic or xenogeneic cells, it is necessary to develop a means by which to isolate administered cells from an immune attack by the host. We have developed “cytomedicine, ” which consists of functional cells entrapped in semipermeable polymer, and previously reported that alginate-poly-l-lysine-alginate microcapsules and agarose microbeads could protect the entrapped cells from injury by cellular immunity. However, their ability to isolate from humoral immunity was insufficient. It is well known that the complement system plays an essential role in rejection of transplanted cells by host humoral immunity. Therefore, the goal of the present study was to develop a novel cytomedical device containing a polymer capable of inactivating complement. In the screening of various polymers, polyvinyl sulfate (PVS) exhibited high anticomplement activity and low cytotoxicity. Murine pancreatic β-cell line (MIN6 cell) entrapped in agarose microbeads containing PVS maintained viability and physiological insulin secretion, replying in response to glucose concentration, and resisted rabbit antisera in vitro. PVS inhibited hemolysis of sensitized sheep erythrocytes (EAs) and rabbit erythrocytes by the complement system. This result suggests that PVS inhibits both the classical and alternative complement pathways of the complement system. Next, the manner in which PVS exerts its effects on complement components was examined. PVS was found to inhibit generation of C4a and Ba generation in activation of the classical and alternative pathways, respectively. Moreover, when the EAC1 cells, which were carrying C1 on the EAs, treated with PVS were exposed to C1-deficient serum, hemolysis decreased in a PVS dose-dependent manner. These results suggest that PVS inhibits C1 in the classical pathway and C3 convertase formation in the alternative pathway. Therefore, PVS may be a useful polymer for developing an anticomplement device for cytomedical therapy.

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Liu, Minbo, Yuanyuan Hu, Yahong Zhang, and Haojie Lu. "Mechanism exploration of adsorption-immobilized enzymatic reactor using polymer-coated silica microbeads." Talanta 110 (June 2013): 101–7. http://dx.doi.org/10.1016/j.talanta.2013.02.021.

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Nagaoka, Shoji, Naoya Ryu, Akio Yamanouchi, Tomohiro Shirosaki, Maki Horikawa, Hideo Sakurai, Makoto Takafuji, and Hirotaka Ihara. "Chemical mechanical polishing of transparent conductive layers using spherical cationic polymer microbeads." Thin Solid Films 576 (February 2015): 31–37. http://dx.doi.org/10.1016/j.tsf.2014.12.028.

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Imanishi, N., Y. Ono, K. Hanai, R. Uchiyama, Y. Liu, A. Hirano, Y. Takeda, and O. Yamamoto. "Surface-modified meso-carbon microbeads anode for dry polymer lithium-ion batteries." Journal of Power Sources 178, no. 2 (April 2008): 744–50. http://dx.doi.org/10.1016/j.jpowsour.2007.09.035.

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Wong, Danny, Jesus Resendiz, Philip Egberts, and Simon S. Park. "Reduction of Friction Using Electrospun Polymer Composite Microbeads Emulsified in Mineral Oil." Procedia Manufacturing 10 (2017): 339–50. http://dx.doi.org/10.1016/j.promfg.2017.07.003.

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Chung, Jinyang, Ee Taek Hwang, Haemin Gang, and Man Bock Gu. "Magnetic-separable robust microbeads using a branched polymer for stable enzyme immobilization." Reactive and Functional Polymers 73, no. 1 (January 2013): 39–45. http://dx.doi.org/10.1016/j.reactfunctpolym.2012.10.001.

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Trojanowska, Anna, Nicolas Pazos-Perez, Cinta Panisello, Tania Gumi, Luca Guerrini, and Ramon A. Alvarez-Puebla. "Plasmonic-polymer hybrid hollow microbeads for surface-enhanced Raman scattering (SERS) ultradetection." Journal of Colloid and Interface Science 460 (December 2015): 128–34. http://dx.doi.org/10.1016/j.jcis.2015.08.047.

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Mitrovic, Dragana, Jasmina Stojkovska, and Bojana Obradovic. "Controlled swelling and degradation studies of alginate microbeads in dilute natrium-citrate solutions." Chemical Industry 64, no. 4 (2010): 253–63. http://dx.doi.org/10.2298/hemind100302038m.

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Alginate hydrogels are widely used in biomedicine due to alginate availability, hydrophilic nature, biocompatibility and biodegradability. Alginate microbeads are particularly attractive for applications in pharmacy and regenerative medicine due to high surface to volume ratio, low mass transfer limitations and simple implantation by injection. Aim of this work was to investigate possibilities for controlled degradation of alginate microbeads in cell culture medium (Dulbecco?s modified Eagle?s medium) with Na-citrate added in small concentrations (0.05 - 0.5 mM). Alginate microbeads (1.5% w/w, 800 m in diameter) were produced by electrostatic droplet extrusion and evaluated over a period of 10 days regarding appearance, kinetics and degree of swelling as well as biomechanical properties determined in a novel bioreactor with mechanical stimulation under in vivo-like conditions in articular cartilage (10% strain, 337.5 m/s compression rate). In the citrate concentration range investigated, microbeads initially swelled reaching an equilibrium value (~150-170% with respect to the initial mass), upon which they appeared stable for a certain period of time (1 to over 7 days) followed by bead bursting and degradation. This degradation process indicated that Na+ ions from the solution initially replaced Ca2+ ions bound mainly to COO- groups in polymannuronate sequences inducing electrostatic repulsion of polymer chains and, consequently, swelling of the beads. Citrate ions assisted in this process by forming insoluble calcium citrate. Thus, the specific rate of the bead swelling increased with the increase in citrate concentration approaching a maximal value of ~0.34 d-1. In the last phase, the beads burst into pieces, which slowly continued to degrade by replacement of Ca2+ ions bonded to polyguluronate blocks in the egg-box structure. Compression moduli for packed beds of control, freshly produced microbeads, and microbeads swelled at the equilibrium degree after 3 days of staying in 0.2 mM Na-citrate solution were 136.6 ? 2.8 and 30.8 ? 1.3 kPa, respectively. By day 7 in this solution, the beads still appearing structurally intact, further lost their mechanical strength due to continued polymer chain relaxation so that the compression modulus was 20.7 to 22.6 kPa owed almost solely to undegraded polyguluronate parts. Results of these studies are important from a fundamental standpoint for determination of structure and degradation mechanisms of alginate hydrogels but also from a practical point of view for optimization of hydrogel properties and behavior for potential applications in controlled drug release as well as in tissue engineering.

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Aswathy, Koranappallil S., Anu M. Abraham, Limiya Jomy, R. Mehaladevi, and Rosemol K. John. "Formulation and evaluation of Etodolac alginate beads prepared by ionotropic gelation for sustained release." Journal of Scientific and Innovative Research 3, no. 5 (October 25, 2014): 527–31. http://dx.doi.org/10.31254/jsir.2014.3511.

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Oral sustained release drug delivery system is getting greater attention due to its therapeutic advantages. Etodolac is a non-steroidal anti-inflammatory drug with potent analgesic and anti-arthritic properties. It has a short biological half life of 6.4 hours and is administered in a dose of 200-400 mg every 6-8 hours. In the present study, a suitable particulate system of Etodolac has been developed, by ionotropic gelation method for sustained release that would result in prolonged clinical efficacy, reduced frequency of administration and lesser side effects. Microbeads were prepared with and without using maize starch as polymer and were evaluated for particle size and size distribution analysis, flow properties, loose surface crystal study, entrapment efficiency, swelling ratio, percentage yield and drug content uniformity and invitro drug release. It was found that the particle size distribution of both formulations was varied within a narrow size range. Drug leaching (15.46 % ± 0.118) was more with presence of maize starch. Entrapment efficiency was retarded with the presence of maize starch. Swelling ratio (54.29 ± 0.151) suggested that maize starch incorporated microbeads swelled more to behave as a matrix for controlled drug delivery. Formation of highly viscous dispersion with the incorporation of polymer led to high percentage yield (51.48% ± 0.180). Drug release data was fitted into various kinetic models and indicated that the mechanism was according to Peppas model. The study revealed that the microbeads of Etodolac could be successfully prepared by ionotropic gelation technique with sustained release characteristics.

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Pham, Q. D., and P. V. Surukov. "Rheological properties of dispersed-filled polymer composite materials based on polyethylene containing glass microbeads." Plasticheskie massy, no. 7-8 (September 18, 2021): 35–38. http://dx.doi.org/10.35164/0554-2901-2021-7-8-35-38.

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This article presents the results of a study of the effect of the filler content on the rheological properties of polymer composite materials based on high density polyethylene containing glass microbeads. The flow curves of the compositions were obtained by the method of capillary viscosimetry. Simple mathematical models have been constructed that allow estimating the viscosity of the compositions’ melts based on a given filler content.

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Sait, Hani Hussain, Ahmed Hussain, Mohamed Bassyouni, Imtiaz Ali, Ramesh Kanthasamy, Bamidele Victor Ayodele, and Yasser Elhenawy. "Anionic Dye Removal Using a Date Palm Seed-Derived Activated Carbon/Chitosan Polymer Microbead Biocomposite." Polymers 14, no. 12 (June 20, 2022): 2503. http://dx.doi.org/10.3390/polym14122503.

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The discharge of textile wastewater into aquatic streams is considered a major challenge due to its effect on the water ecosystem. Direct blue 78 (DB78) dye has a complex structure. Therefore, it is difficult to separate it from industrial wastewater. In this study, carbon obtained from the pyrolysis of mixed palm seeds under different temperatures (400 °C and 1000 °C) was activated by a thermochemical method by using microwave radiation and an HCl solution in order to improve its adsorption characteristics. The generated activated carbon was used to synthesize a novel activated carbon/chitosan microbead (ACMB) for dye removal from textile wastewater. The obtained activated carbon (AC) was characterized by a physicochemical analysis that included, namely, particle size, zeta potential, SEM, EDX, and FTIR analyses. A series of batch experiments were conducted in terms of the ACMB dose, contact time, pH, and activated carbon/chitosan ratios in synthetic microbeads for enhancing the adsorption capacity. A remarkable improvement in the surface roughness was observed using SEM analysis. The particle surface was transformed from a slick surface with a minor-pore structure to a rough surface with major-pore structure. The zeta potential analysis indicated a higher improvement in the carbon surface charge, from −35 mv (before activation) to +20 mv (after activation). The adsorption tests showed that the dye-removal efficiency increased with the increasing adsorbent concentration. The maximum removal efficiencies were 97.8% and 98.4% using 3 and 4 g/L of AC400°C MB-0.3:1 and AC1000°C MB-0.3:1, respectively, with initial dye concentrations of 40 mg/L under acidic conditions (pH = 4–5), and an optimal mixing time of 50 min. The equilibrium studies for AC400°C MB-0.3:1 and AC1000°C MB-0.3:1 showed that the equilibrium data best fitted to the Langmuir isothermal model with R2 = 0.99. These results reveal that activated carbon/chitosan microbeads are an effective adsorbent for the removal of direct blue 78 dye and provide a new platform for dye removal.

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PHAM, Q. D., and P. V. SURIKOV. "Tensile rheological properties of melts of dispersion-filled polymer composites based on polyethylene containing glass microbeads." Plasticheskie massy 1, no. 5-6 (August 8, 2022): 16–19. http://dx.doi.org/10.35164/0554-2901-2022-5-6-16-19.

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The paper presents the results of the study of rheological properties of melts of dispersion-filled polymer materials based on polyethylene containing glass microbeads manifested under tensile stress in a thermostating bath. The dependences of tensile multiplicity on loading time are plotted, models describing the processes of stretching and subsequent relaxation are presented, the value of relative viscosity of composite materials is obtained.

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Boppana, Rashmi, Raghavendra V. Kulkarni, G. Krishna Mohan, Srinivas Mutalik, and Tejraj M. Aminabhavi. "In vitro and in vivo assessment of novel pH-sensitive interpenetrating polymer networks of a graft copolymer for gastro-protective delivery of ketoprofen." RSC Advances 6, no. 69 (2016): 64344–56. http://dx.doi.org/10.1039/c6ra04218j.

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KOTANI, Masaki, Kazuaki NISHIYABU, Satoru MATSUZAKI, and Shigeo TANAKA. "Processing of polymer-derived porous SiC body using allylhydridopolycarbosilane (AHPCS) and PMMA microbeads." Journal of the Ceramic Society of Japan 119, no. 1391 (2011): 563–69. http://dx.doi.org/10.2109/jcersj2.119.563.

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43

Cui, Xiaoling, Hong Shao, Yuanrui Song, Song Yang, Fengwei Wang, and Huarong Liu. "Preparation of highly interconnected porous polymer microbeads via suspension polymerization of high internal phase emulsions for fast removal of oil spillage from aqueous environments." RSC Advances 9, no. 44 (2019): 25730–38. http://dx.doi.org/10.1039/c9ra05220h.

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44

Haimhoffer, Ádám, Alexandra Vas, Gabriella Árvai, Éva Fenyvesi, László Jicsinszky, István Budai, Attila Bényei, et al. "Investigation of the Drug Carrier Properties of Insoluble Cyclodextrin Polymer Microspheres." Biomolecules 12, no. 7 (July 2, 2022): 931. http://dx.doi.org/10.3390/biom12070931.

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The investigation of the usability of solid insoluble β-cyclodextrin polymers (βCDP) in micro-sized, controlled drug delivery systems has only recently attracted interest. Our aim was to form complexes with poorly soluble active pharmaceutical ingredients (APIs) with two types of βCDP for drug delivery applications. Solid insoluble cyclodextrin polymer of irregular shape (βCDPIS) and cyclodextrin microbeads (βCDPB) were used in the experiments. Morphology, surface area, size distribution and swelling capacity of carriers were investigated. We created complexes with two APIs, curcumin and estradiol, and applied powder X-ray diffraction, FTIR and thermal analysis (TGA/DSC) to prove the complexation. Finally, the dissolution, biocompatibility and permeation of APIs on Caco-2 cells were investigated. The size of the beads was larger than 100 µm, their shape was spherical and surfaces were smooth; while the βCDPIS particles were around 4 µm with irregular shape and surface. None of the polymers showed any cytotoxic effect on Caco-2 cells. Both carriers were able to extract curcumin and estradiol from aqueous solutions, and the dissolution test showed prolonged estradiol release. Caco-2 permeability tests were in accordance with the complexation abilities and dissolution of the complexes. This study offers useful data for further pharmaceutical applications of insoluble cyclodextrin polymers.

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Nath, Bipul, and Santimoni Saikia. "Characterization and Screening of a Novel Multiparticulate Pulsatile Delivery of Aceclofenac." International Journal of Pharmaceutical Sciences and Nanotechnology 9, no. 5 (September 30, 2016): 3494–501. http://dx.doi.org/10.37285/ijpsn.2016.9.5.7.

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In the present investigation, sodium alginate based multiparticulate system overcoated with time and pH dependent polymer was studied in the form of oral pulsatile system to achieve pulsatile with sustained release of aceclofenac for chronotherapy of rheumatoid arthritis seven batches of micro beads with varying concentration of sodium alginate (2-5 %) were prepared by ionotropic-gelation method using CaCl2 as cross-linking agent. The prepared Ca-alginate beads were coated with 5% Eudragit L100 and filled into pulsatile capsule with varying proportion of plugging materials. Drug loaded microbeads were investigated for physicochemical properties and drug release characteristics. The mean particle sizes of drug-loaded microbeads were found to be in the range 596±1.1 to 860 ± 1.2 micron and %DEE in the range of 65-85%. FT-IR and DSC studies revealed the absence of drug polymer interactions. The release of aceclofenac from formulations F1 to F7 in buffer media (pH 6.8) at the end of 5h was 65.6, 60.7, 55.7, 41.2, 39.2, 27 and 25% respectively. Pulsatile system filled with eudragit coated Ca-alginate microbeads (F2) showed better drug content, particle size, surface topography, in-vitro drug release in a controlled manner. Different plugging materials like Sterculia gum, HPMC K4M and Carbopol were used in the design of pulsatile capsule. The pulsatile system remained intact in buffer pH 1.2 for 2 hours due to enteric coat of the system with HPMCP. The enteric coat dissolved when the pH of medium was changed to 7.4. The pulsatile system developed with Sterculia gum as plugging material showed satisfactory lag period when compared to HPMC and Carbopol.

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Kostic, Ivana, Bojana Isailovic, Verica Djordjevic, Steva Levic, Viktor Nedovic, and Branko Bugarski. "Electrostatic extrusion as a dispersion technique for encapsulation of cells and bioactive compounds." Chemical Industry 66, no. 4 (2012): 505–17. http://dx.doi.org/10.2298/hemind111209013k.

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Significant development of cells and bioactive compound encapsulation technologies is taking place due to an exceptional possibility of their application in various scientific disciplines, including biomedicine, pharmacy, cosmetology, food and agricultural sciences, beverage production, industrial waste treatment. Despite the broad application of microencapsulation, the literature reviews on dispersion techniques for microcapsule/microbead production, their advantages, restrictions and drawbacks are scarce. The purpose of this paper is to assess the possibilities of electrostatic extrusion for encapsulation of biological material, including living cells in hydrogel microbeads. The paper presents an overview of the mechanisms of droplet formation and controlling experimental parameters for producing microbeads by means of electrostatic extrusion. Electrostatic droplet formation utilizes a special type of physical process taking advantage of electrostatic effects occurring in flowing conductive liquids after introduction of an electric field.When an electrostatic field is applied to the metal needle and an electric charge is induced in the liquid flowing out of the needle, the size of droplet detaching from the needle tip decreases as a funcion of applied electrostatic field. It has been shown that few parameters affect microbead size: applied voltage, electrode geometry, needle size, polarity arrangement and polymer concentration. The electrostatic droplet formation is one of the most precise methods, which enables one to produce spherical and uniform particles ranging from 100 ?m up to 1000 ?m. Most of the authors report that the encapsulated compounds (drugs, enzymes and living cells) remain unaltered after electrostatic extrusion. This technique seems to be particularly promising in biotechnology, pharmaceutical and cosmetics industries, where a low-temperature process, preserving heat-sensitive material is a prerequisite. Future efforts in developing of electrostatic extrusion should be directed towards adequately scaling-up for commercial purpose.

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Manojlovic, Verica, Jasna Djonlagic, Bojana Obradovic, Viktor Nedovic, and Branko Bugarski. "Effects of cell addition on immobilization by electrostatic droplet generation." Chemical Industry and Chemical Engineering Quarterly 11, no. 2 (2005): 79–84. http://dx.doi.org/10.2298/ciceq0502079m.

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In this study, an attempt was made to assess the effects of cell addition and final concentration on the process of electrostatic extrusion as a method for cell immobilization in alginate microbeads. The electrostatic extrusion process is a complex function of several operating parameters, the system geometry, and the properties of the polymer solution, which is being extruded. The addition of cells results in the formation of a two-phase system, adding to the complexity of the process by the associated phenomenon of two-phase flow. This study especially focused on analyzing the effects of cell presence on each stage of the immobilization process. Specifically, the effects of the cell and alginate concentrations on the resulting microbead size and uniformity were assessed. Under the investigated conditions, microbeads, 50-600 ?m in diameter, were produced and the increase in both alginate and cell concentrations resulted in larger microbeads with higher standard deviations in size. We attempted to rationalize the obtained findings by rheological characterization of the cell-alginate suspensions. H-NMR Spectroscopy of the alginate used in this study revealed a high content (67%) of guluronic residues and GG diad blocks (FGG = 55%). The mole fractions of the MM and GM diad sequences, Fmm and Fgm, were 21 and 12%, respectively. Rheological characterization revealed non-Newtonian, pseudoplastic behavior of the cell-alginate suspensions with an increase in viscosity as the alginate concentration was increased. However, the presence of cells even at high concentrations (5 ? 108 and 1 ? 109 cell/ml) did not significantly affect the rheological properties of Na alginate solution. Finally, the effects of the alginate and cell concentrations on the gelation kinetics and the dynamic-mechanical behavior of the obtained hydrogels were investigated. A molar ratio of G units to Ca2+ ions of 3.8 : 1 provided complete crosslinking, while an increase in the alginate concentration resulted in prolonged gelation times, but higher strength of the resulting gel. Cell presence decreased the rate of network formation, as well as the strength of the obtained Ca alginate hydrogel.

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Uygun, Zihni Onur, Burcu Okutucu, Şükriye Hacikara, and Ferhan Sağın. "Development of molecularly imprinted Acrylamide-Acrylamido phenylboronic acid copolymer microbeads for selective glycosaminoglycan separation in children urine." Turkish Journal of Biochemistry 44, no. 6 (December 18, 2019): 738–44. http://dx.doi.org/10.1515/tjb-2018-0413.

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Abstract Background In this study, we synthesized molecularly imprinted copolymers for liquid chromatography columns as a separator for glycosaminoglycan (dermatan sulfate; DS and chondroitin sulfate; CS) in urine. Materials and methods Acrylamide and acrylamido phenylboronic acid were used as monomers, acrylamide was used for as base monomer to attract negatively charged groups and acrylamido phenylboronic acid (AAPBA) residues used to form diol bonds between sugar and boronic acid residues to strengthen the attraction. These monomers were synthesized by using precipitation polymerization to form uniform spheres, which are more durable for the pressurized chromatographic systems. Trimethylolpropane trimethacrylate and AIBN were used as crosslinker and starter, respectively. Results These GAG selective polymers were filled by pressurized flow into the steel (4.6 mm × 1.6 mm) columns, then imprinted GAGs were extracted and analyzed to calculate binding capacity of each milligram polymer. Calibration curves of the GAG selective columns were obtained 62.5–1000 ng/mL less than 5% coefficient variation, and lower matrix effect. Conclusion Our imprinted columns separated different GAGs from urine specifically and sensitively. Matrix effect was at an ignorable level thus the challenging use.

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Guo, Xiaoying, Yueping Guan, Bin Yang, Yongning Wang, Hualong Lan, Wentang Shi, Zhenghui Yang, and Zuhong Lu. "Enzyme Chemiluminescence Immuno Assay of Free hCGβ in Serum Based on Superparamagnetic Polymer Microbeads." International Journal of Molecular Sciences 7, no. 8 (August 24, 2006): 274–88. http://dx.doi.org/10.3390/i7080274.

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Yoon, Tae-Ho, Lan-Young Hong, and Dong-Pyo Kim. "Photocatalytic reaction using novel inorganic polymer derived packed bed microreactor with modified TiO2 microbeads." Chemical Engineering Journal 167, no. 2-3 (March 2011): 666–70. http://dx.doi.org/10.1016/j.cej.2010.08.090.

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