Bibliografías temáticas / Chitosan beads

Literatura académica sobre el tema "Chitosan beads"

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Publicado: 14 de marzo de 2023

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Artículos de revistas sobre el tema "Chitosan beads"

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Worthen, Andrew, Kelly Irving y Yakov Lapitsky. "Supramolecular Strategy Effects on Chitosan Bead Stability in Acidic Media: A Comparative Study". Gels 5, n.º 1 (25 de febrero de 2019): 11. http://dx.doi.org/10.3390/gels5010011.

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Chitosan beads attract interest in diverse applications, including drug delivery, biocatalysis and water treatment. They can be formed through several supramolecular pathways, ranging from phase inversion in alkaline solutions, to the ionic crosslinking of chitosan with multivalent anions, to polyelectrolyte or surfactant/polyelectrolyte complexation. Many chitosan bead uses require control over their stability to dissolution. To help elucidate how this stability depends on the choice of supramolecular gelation chemistry, we present a comparative study of chitosan bead stability in acidic aqueous media using three common classes of supramolecular chitosan beads: (1) alkaline solution-derived beads, prepared through simple precipitation in NaOH solution; (2) ionically-crosslinked beads, prepared using tripolyphosphate (TPP); and (3) surfactant-crosslinked beads prepared via surfactant/polyelectrolyte complexation using sodium salts of dodecyl sulfate (SDS), caprate (NaC10) and laurate (NaC12). Highly variable bead stabilities with dissimilar sensitivities to pH were achieved using these methods. At low pH levels (e.g., pH 1.2), chitosan/SDS beads were the most stable, requiring roughly 2 days to dissolve. In weakly acidic media (at pH 3.0–5.0), however, chitosan/TPP beads exhibited the highest stability, remaining intact throughout the entire experiment. Beads prepared using only NaOH solution (i.e., without ionic crosslinking or surfactant complexation) were the least stable, except at pH 5.0, where the NaC10 and NaC12-derived beads dissolved slightly faster. Collectively, these findings provide further guidelines for tailoring supramolecular chitosan bead stability in acidic media.
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Jobin, Guy, Gilles Grondin, Geneviève Couture y Carole Beaulieu. "Microscopic Examination of Chitosan–Polyphosphate Beads with Entrapped Spores of the Biocontrol Agent,Streptomyces melanosporofaciensEF-76". Microscopy and Microanalysis 11, n.º 2 (8 de marzo de 2005): 154–65. http://dx.doi.org/10.1017/s1431927605050142.

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Spores of the biocontrol agent,Streptomyces melanosporofaciensEF-76, were entrapped by complex coacervation in beads composed of a macromolecular complex (MC) of chitosan and polyphosphate. A proportion of spores entrapped in beads survived the entrapment procedure as shown by treating spores from chitosan beads with a dye allowing the differentiation of live and dead cells. The spore-loaded chitosan beads could be digested by a chitosanase, suggesting that, once introduced in soil, the beads would be degraded to release the biocontrol agent. Spore-loaded beads were examined by optical and scanning electron microscopy because the release of the biological agent depends on the spore distribution in the chitosan beads. The microscopic examination revealed that the beads had a porous surface and contained a network of inner microfibrils. Spores were entrapped in both the chitosan microfibrils and the bead lacuna.
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Steiger, Bernd G. K. y Lee D. Wilson. "Modular Chitosan-Based Adsorbents for Tunable Uptake of Sulfate from Water". International Journal of Molecular Sciences 21, n.º 19 (27 de septiembre de 2020): 7130. http://dx.doi.org/10.3390/ijms21197130.

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The context of this study responds to the need for sorbent technology development to address the controlled removal of inorganic sulfate (SO42−) from saline water and the promising potential of chitosan as a carrier system for organosulfates in pharmaceutical and nutraceutical applications. This study aims to address the controlled removal of sulfate using chitosan as a sustainable biopolymer platform, where a modular synthetic approach was used for chitosan bead preparation that displays tunable sulfate uptake. The beads were prepared via phase-inversion synthesis, followed by cross-linking with glutaraldehyde, and impregnation of Ca2+ ions. The sulfate adsorption properties of the beads were studied at pH 5 and variable sulfate levels (50–1000 ppm), where beads with low cross-linking showed moderate sulfate uptake (35 mg/g), while cross-linked beads imbibed with Ca2+ had greater sulfate adsorption (140 mg/g). Bead stability, adsorption properties, and the point-of-zero charge (PZC) from 6.5 to 6.8 were found to depend on the cross-linking ratio and the presence of Ca2+. The beads were regenerated over multiple adsorption-desorption cycles to demonstrate the favorable uptake properties and bead stability. This study contributes to the development of chitosan-based adsorbent technology via a modular materials design strategy for the controlled removal of sulfate. The results of this study are relevant to diverse pharmaceutical and nutraceutical applications that range from the controlled removal of dextran sulfate from water to the controlled release of chondroitin sulfate.
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Mahasawat, Pawika, Ketsarin Hlongkeaw y Sutthida Charoenrit. "Effect of Chitosan and Alginate Concentration on Size and Bactericidal Activity against Escherichia coli of Chitosan/Alginate/Silver Nanoparticle Beads". Applied Mechanics and Materials 855 (octubre de 2016): 54–59. http://dx.doi.org/10.4028/www.scientific.net/amm.855.54.

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Silver nanoparticles have been used in combination with biological polymer for antibacterial application. This study prepared chitosan/alginate/AgNP beads with varying chitosan and alginate concentration to use as an antibacterial material. The sizes of neat beads were larger (1286 ± 172, 1344 ± 142 and 1529 ± 73 μm for C1, C2 and C3, respectively) with increasing concentration of chitosan and alginate. Moreover, smaller beads were observed for the chitosan/alginate/AgNP beads, in which their sizes were 1151 ± 201, 1261 ± 204 and 1324 ± 198 µm for S1, S2 and S3, respectively, when compared to the chitosan/alginate beads. Furthermore, the minimum bactericidal concentration (MBC) of chitosan/alginate/AgNP beads against E. coli was 10, 10 and 3 µg/ml for S1, S2 and S3, respectively. This study suggested that the beads with the higher concentration of chitosan and alginate resulted in the greater bactericidal activity. Therefore, the chitosan/alginate/AgNP beads prepared in this study showed the bactericidal activity which can be used for antibacterial application.
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Wang, Taoran y Yangchao Luo. "Chitosan Hydrogel Beads Functionalized with Thymol-Loaded Solid Lipid–Polymer Hybrid Nanoparticles". International Journal of Molecular Sciences 19, n.º 10 (11 de octubre de 2018): 3112. http://dx.doi.org/10.3390/ijms19103112.

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In this study, the innovative and multifunctional nanoparticles–hydrogel nanocomposites made with chitosan hydrogel beads and solid lipid–polymer hybrid nanoparticles (SLPN) were prepared through conjugation between SLPN and chitosan beads. The SLPNs were first fabricated via coating the bovine serum albumin (BSA)-emulsified solid lipid nanoparticles with oxidized dextran. The aldehyde groups of the oxidized dextran on the surface of the SLPN enabled an in situ conjugation with the chitosan beads through the Schiff base linkage. The obtained nano-on-beads composite exhibited a spherical shape with a homogeneous size distribution. The successful conjugation of SLPN on the chitosan beads was confirmed by a Fourier transform infrared spectroscopy and a scanning electron microscope. The effects of the beads dosage (50, 100, 200, and 300 beads) and the incubation duration (30, 60, 90, 120, and 150 min) on the conjugation efficiency of SLPN onto the beads were comprehensively optimized. The optimal formulations were found to be a 200 bead dosage, with 30–90 min incubation duration groups. The optimal formulations were then used to encapsulate thymol, an antibacterial agent, which was studied as a model compound. After encapsulation, the thymol exhibited sustained release profiles in the phosphate buffer saline. The as-prepared nanoparticles–hydrogel nanocomposites reported in this proof-of-concept study hold promising features as a controlled-release antibacterial approach for improving food safety.
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Sabarudin, Akhmad y Armeida D. R. Madjid. "Preparation and Kinetic Studies of Cross-Linked Chitosan Beads Using Dual Crosslinkers of Tripolyphosphate and Epichlorohydrin for Adsorption of Methyl Orange". Scientific World Journal 2021 (17 de febrero de 2021): 1–11. http://dx.doi.org/10.1155/2021/6648457.

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Preparation of cross-linked chitosan beads using dual crosslinkers of tripolyphosphate (TPP) and epichlorohydrin (ECH) for the adsorption and kinetic studies of methyl orange (MO) had been carried out. FTIR spectra showed that TPP could act as the protecting agent of the NH2 group of chitosan and ECH reacted with the primary hydroxyl group of chitosan. Various concentrations of TPP, ECH, and immersing time in the TPP solution for bead formation were studied. The effect of pH and kinetics of adsorption were investigated to define the mechanism of adsorption and rate-limiting step. As a result, pH 3, 10% (w/v) TPP, 5% (v/v) ECH, and 12 h immersing time in TPP were selected as the optimum conditions for preparing the beads as indicated by the highest adsorption amount of MO. The cross-linked chitosan beads’ adsorption capacity for MO under optimum condition was found to be 79.55 mg/g with the adsorption rate constant (k) of 1.29 × 10−3/min. Furthermore, it was found that a low concentration of ECH could maintain the stability of chitosan in acidic conditions, whereas the concentration of TPP and immersing time controlled pore size and morphology of chitosan beads. The mechanism of adsorption of MO was controlled by the pore and rigidity of cross-linked chitosan beads. Bulk diffusion acted as a rate-limiting step, and a high concentration of MO inhibited diffusion and adsorption itself.
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7

Li, N. y R. Bai. "Development of chitosan-based granular adsorbents for enhanced and selective adsorption performance in heavy metal removal". Water Science and Technology 54, n.º 10 (1 de noviembre de 2006): 103–13. http://dx.doi.org/10.2166/wst.2006.736.

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Novel chitosan-based granular adsorbents were developed for enhanced and selective separation of heavy metal ions. The research included the synthesis of chitosan hydrogel beads, the cross-linking of the hydrogel beads with ethylene glycol diglycidyl ether (EGDE) in a conventional and a novel amine-shielded method, the functionalization of the chitosan beads through surface grafting of polyacrylamide via a surface-initiated atom transfer radical polymerization (ATRP) method, and the examination of the adsorption performance of the various types of chitosan beads in the removal of heavy metal ions. It was found that chitosan beads were effective in heavy metal adsorption, the conventional cross-linking method improved the acidic stability of the beads but reduced their adsorption capacity, the novel amine-shielded cross-linking method retained the good adsorption capacity while it improved the acidic stability of the beads, and the grafting of polyacrylamide on chitosan beads not only enhanced the adsorption capacity but also provided the beads with excellent selectivity for mercury over lead ions. XPS analyses indicated that the adsorption of metal ions on chitosan beads was mainly attributed to the amine groups of chitosan, the novel amine-shielded cross-linking method preserved most of the amine groups from being consumed by the cross-linking process and hence improved the adsorption capacity of the cross-linked chitosan beads, and the many amide groups from the polyacrylamide grafted on the chitosan beads increased the adsorption capacity and also made possible selective adsorption of mercury ions because the amide groups can form covalent bonds with mercury ions.
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Li, Hao, Jin Wang, Yu Luo, Bo Bai y Fangli Cao. "pH-Responsive Eco-Friendly Chitosan–Chlorella Hydrogel Beads for Water Retention and Controlled Release of Humic Acid". Water 14, n.º 8 (8 de abril de 2022): 1190. http://dx.doi.org/10.3390/w14081190.

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For improving the mechanical strength of controlled release fertilizer (CRF) hydrogels, a novel material of Chlorella was employed as a bio-based filler to prepare chitosan–chlorella hydrogel beads with physical crosslink method. Here, the synthesis mechanism was investigated, and the chitosan–chlorella hydrogel beads exhibited enhanced mechanical stability under centrifugation and sonication than pure chitosan hydrogel beads. Chlorella brought more abundant functional groups to original chitosan hydrogel, hence, chitosan–chlorella hydrogel beads represented greater sensitivity and controllable response to external factors including pH, salt solution, temperature. In distilled water, the hydrogel beads with 40 wt% Chlorella reached the largest water absorption ratio of 42.92 g/g. Moreover, the mechanism and kinetics process of swelling behavior of the chitosan–chlorella hydrogel beads were evaluated, and the loading and releasing of humic acid by the hydrogel beads as a carrier material were pH-dependent and adjustable, which exhibit the potential of chitosan–chlorella hydrogel beads in the field of controlled release carrier biomaterials.
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Wulan, Putri, Yuni Kusumastuti y Agus Prasetya. "Removal of Fe (II) from Aqueous Solution by Chitosan Activated Carbon Composite Beads". Applied Mechanics and Materials 898 (mayo de 2020): 3–8. http://dx.doi.org/10.4028/www.scientific.net/amm.898.3.

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The high levels of Fe2+ metal ion in water can be reduced by adsorption process. The adsorbent used is a composite of chitosan activated carbon. The composites were prepared by adding 1.5 g of activated carbon into chitosan solution 1.5% (w/v). The gels of chitosan activated carbon were then dropped into a 2.8% NaOH solution mixture to produce composite beads. The beads were neutralized using aquadest and dried in an oven at 50oC for 2 hours. The dried bead was used as adsorbent. The adsorption process was carried out with erlenmeyer in shaker bath with 0.5 g, 1 g, and 1.5 g at 25oC, 35oC and 45oC in 50 mL solution of Fe2+ metal ion having concentration of 10 ppm. Sample were taken in 5, 10, 20, 40 60, 80 and 120 min. Adsorbent were characterized by SEM and EDX. The composite beads adsorbent was analyzed by SEM and EDX. SEM results show that chitosan was successfully coated on activated carbon with a porous surface structure. The EDX results show that chitosan activated carbon composite beads can absorb Fe2+ metal ions, with an adsorption capacity of 88.3% at 60 min in 1.5 g adsorbent dose.
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Piluarto, Bambang, Yusril Ihza Mahendra y Novita Andarini. "HYBRID KITOSAN/BENTONIT SEBAGAI MATRIKS UNTUK PELEPASAN ION AMONIUM DALAM AIR". Jurnal Kimia Riset 1, n.º 1 (1 de junio de 2016): 42. http://dx.doi.org/10.20473/jkr.v1i1.2441.

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AbstrakHybrid kitosan/bentonit dalam bentuk bead telah berhasil dibuat dengan berbagai rasio komposisi kitosan dan bentonit. Dalam penelitian ini, bead dari hybrid ini digunakan sebagai matriks untuk ion amonium. Bead dibuat dengan pengendapan suspensi kitosan dan bentonit menggunakan koagulan NaOH. Bead hybrid yang diperoleh dikarakterisasi daya serap air (DSA) dan pelepasan ion amonium dalam air. Hasil yang diperoleh menunjukkan bahwa bentuk bead dipengaruhi oleh kandungan bentonit dalam hybrid. Peningkatan kandungan bentonit dalam hybrid menurunkan nilai DSA, namun meningkatkan pelepasan ion amonium dalam air. Sisa basa pada permukaan bead hybrid mempengaruhi deteksi pelepasan ion amonium dalam air. Kata kunci: hybrid, bead, suspensi, daya serap air, pelepasan ion AbstractChitosan/bentonite hybrid in the form of beads was successfully prepared in various of chitosan and bentonite composition ratio. In this study, beads of hybrid play role as matrix for ammonium ions. Beads prepared by precipitation of chitosan and bentonite suspension using NaOH as coagulant. Characterization beads obtained were carried out on water uptake and release of ammonia ions in the water. The results showed that forms of bead were affected by bentonite content in the hybrid. Increasing of bentonite content decreased water uptake of hybrid, however the release of ammonia ions in the water increased. Remaining base in the beads surface affected detection of release of ammonia ions in the water. Keywords: hybrid, beads, suspension, water uptake, release of ions
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Tesis sobre el tema "Chitosan beads"

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Merrifield, John D. "Synthesis and Characterization of Thiol-Grafted Chitosan Beads for Mercury Removal". Fogler Library, University of Maine, 2002. http://www.library.umaine.edu/theses/pdf/MerrifieldJD2002.pdf.

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Pickens, Tara L. L. "Immobilization of Beta-Glycosidase BglX from Escherichia coli on Chitosan Gel Beads". Youngstown State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1535472543349818.

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Havenga, John Botha. "Chitosan beads as a delivery vehicle for the antituberculosis drug pyrazinamide / J.B. Havenga". Thesis, North-West University, 2006. http://hdl.handle.net/10394/1354.

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DeGroot, Andreas R. "Encapsulation of urease in alginate beads and protection from alpha-chymotrypsin with chitosan membrane". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0004/MQ44002.pdf.

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Mohlala, Mangaabane Gorden. "The effect of pharmaceutical excipients on rifampicin release from chitosan beads / Mangaabane Gorden Mohlala". Thesis, North-West University, 2004. http://hdl.handle.net/10394/484.

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Controlled release systems aim at achieving a predictable and reproducible drug release over a desired time period. These systems allow reduced dosing frequency, constant drug levels in the blood, increased patient compliance and decreased adverse effects. In a recent study, Chitosan beads, containing N-trimethyl Chitosan chloride, have shown a potential in the delivery of rifampicin. However, because of inadequate amounts of rifampicin released over 24 hours, incorporation of other pharmaceutical excipients to increase the swelling behaviour of the beads to improve drug release, was considered in this study. Chitosan beads were prepared through ionotropic gelation with tripolyphosphate (TPP) as a crosslinking agent. To increase the porosity if the Chitosan beads Explotab®, Ac-Di-Sol® and vitamin C were added individually to Chitosan solutions at concentrations of 0.1, 0.25 and 0.5 % w/v before adding the mixture to the TPP solution. Swelling and morphology studies were used in the evaluation of the different formulations. The swelling and morphology results were then used to select a set of combination and concentrations of two excipients sand then prepare and characterise beads containing two combinations. The combination formulations and formulations containing single excipients were then loaded with rifampicin. Pure chitosan beads exhibited a higher drug loading capacity (67.49 %) compared to the lowest loading capacity of 41.61 % exhibited by chitosan beads containing a combination of Explotab®, Ac-Di-Sol®.For all the other formulations the drug loading capacity ranged within 48 and 63 %. These formulations were used for dissolution studies over a period of 6 hours at pH 5.60 and 7.40. The dissolution results showed that no chitosan has dissolved at both pH values. A significant amount of rifampicin was, however, released from the beads, especially at pH 7.40. chitosan beads containing vitamin C also exhibited high rifampicin release (48.34 ± 1.00) %) at pH 5.60 compared to the other formulations and this makes vitamin C a potential excipient for enhanced drug release over a wide pH range (both acidic and alkalinic). However, further studies are necessary to optimise the preparation method to minimise drug loss during loading and to improve the drug loading capacity of the beads.
Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2005.
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Van, Rensburg Andries Gideon. "The effect of pharmaceutical excipients on isoniazid release from chitosan beads / Deon van Rensburg". Thesis, North-West University, 2007. http://hdl.handle.net/10394/1248.

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In controlled release applications a drug is molecularly dispersed in a polymer phase. In the presence of a thermodynamically compatible solvent, swelling occurs and the polymer releases its content to the surrounding medium. The rate of the drug release can be controlled by interfering with the swelling rate of the beads or by influencing diffusion through the viscosity of the polymer. Beads that contain chitosan were prepared through the ionotropic gelation method where tripolyphosphate (TPP) was used as the crosslinking agent. Beads that consisted of 3% w/v isoniazid (lNH) and 5% w/v chitosan were prepared in a 5% w/v TPP solution (pH 8.7) as the primary beads. To improve the drug loading of chitosan isoniazid beads (ClB) the TPP concentration, pH of the TPP solution and the INH concentrations were altered for maximum drug loading. To increase the porosity of the beads of chitosan beads Explotab® (EXPL), Ac-Di-Sol® (ADS) and Vitamin C (VC) were added individually to chitosan solutions at concentrations of 0.1, 0.25 and 0.5% w/v before adding the mixture to the TPP solution. Morphology, swelling and drug loading studies were used to evaluate the different formulations. After these excipients were added individually they were also added in combinations of two excipients respectively and characterised. From the results of the drug loading studies the beads that contained only chitosan and isoniazid showed a percentage drug loading of (43.92%) which is the best of all the beads that were analyzed. The multi excipient combination of Ac-Di-Sol® and Explotab® showed the best swelling capability at both pH levels. Dissolution studies were conducted on all the formu lations over a period of 6 hours (360 minutes) at pH 5.6 and pH 7.4. From the dissolution results it were clear that no chitosan dissolved at both pH values. The dissolution of single pharmaceutical excipient (SPE) and multi pharmaceutical excipient (MPE) formulations can be arranged in the following order: VC/ADS < VC < ADS/EXPL < ADS < VC/EXPL < CIB < EXPL. Explotab® is a potential excipient for enhanced drug release over a wide pH range.
Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2007.
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Havinga, Riana. "The effect of pharmaceutical excipients on the release of indomethacin from chitosan beads / Riana Havinga". Thesis, North-West University, 2006. http://hdl.handle.net/10394/4.

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Contents: Chitosan -- Controlled drug delivery -- Indomethacin -- Inotropic gelation -- Tripolyphosphate (TPP) -- Explotab® -- Ac-Di-Sol® -- Vitamin C
Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2007.
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Osifo, Peter Ogbemudia. "The use of chitosan beads for the adsorption and regeneration of heavy metals / Peter Ogbemudia Osifo". Thesis, North-West University, 2007. http://hdl.handle.net/10394/1635.

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Gündüz, Meltem Harsa Şebnem. "Lactic acid production by lactobacillus casei nrrl b-441 immobilized in chitosan stabilized ca-alginate beads/". [s.l.]: [s.n.], 2005. http://library.iyte.edu.tr/tezler/master/gidamuh/T000427.pdf.

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Bouwer, Carel Petrus. "A comparison on the release modifying behaviour of chitosan and kollidon SR / Carel Petrus Bouwer". Thesis, North-West University, 2007. http://hdl.handle.net/10394/1065.

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Controlled release formulations deliver an active ingredient over an extended period of time. It is an ideal dosage form for an active ingredient with a short elimination half-life. An active ingredient with a short elimination half-life would be released in small portions over an extended period of time and thus less frequent administration is necessary and this improve patient compliance. Other advantages of these formulations include: decreased side effects, constant drug levels in the blood, improvement in treatment efficiency and reduction in cost of administration. Controlled release beads are formulated in such a way that the active ingredient is embedded in a matrix of insoluble substance like chitosan; the dissolving drug then has to find its way through the pores of the matrix into the surrounding medium. The chitosan matrix swells to form a gel, the drug then has to first dissolve in the matrix and diffuse through the outer surface into the surrounding medium. Chitosan is a biocompatible, biodegradable polymer of natural origin. It has mucoadhesive properties as well as the ability to manipulate the tight junctions in the epithelium membrane and these properties have qualified chitosan as an effective drug carrier in controlled release dosage forms. The effect of a modern controlled release polymer namely Kollidon® SR in combination with chitosan on drug release was investigated. Ketoprofen was chosen as model drug. Ketoprofen is an anti-inflammatory drug that causes gastrointestinal side effects in conventional dosage forms. Ketoprofen has a short elimination half-life of 2.05 ± 0.58 h and this characteristic makes it an ideal candidate for use in a controlled release formulation. The aim of this study was to achieve controlled release and minimize gastrointestinal effects of ketoprofen with chitosan particles. Kollidon® SR was used as polymer because it exhibits pH independent release characteristics and previous studies have shown potential for this combination. Chitosan beads and chitosan-Kollidon® SR beads, as well as chitosan granules and chitosan-Kollidon® SR granules, were prepared and investigated as potential controlled release formulations. Chitosan beads were prepared through the inotropic gelation method using tripolyphosphate as a cross linking agent. Granules were prepared through wet granulation using 2% v/v acetic acid as the granulating fluid or by dissolving ketoprofen in ethanol and Kollidon® SR in 2-pyrrolidinone and using the solution as granulating fluid. Kollidon® SR was added in concentrations of 0.25, 0.5 and 1% (w/v) in the bead formulations and concentrations of 1, 5 and 10% (w/w) in the granule formulations. The beads and granules were characterised by evaluating the following properties: morphology, drug loading and drug release. Additionally swelling and friability tests were also conducted on the bead formulations. The cross linking times of the bead formulations were varied to investigate the effect of cross linking time on the characteristics of the beads. Chitosan-Kollidon® SR beads showed promising results for controlled release formulations and ketoprofen were released over an extended period of time. Drug loading of the plain chitosan beads was 74.65 ± 0.71% and it was noted that the inclusion of Kollidon® SR in the beads resulted in an increase in drug loading and the formulation containing 1% (w/v) Kollidon® SR, cross linked for 30 minutes had a drug loading of 77.38 ± 0.01%. Drug loading of the beads that were cross linked for a longer time were slightly lower which is an indication that some of the drug might have leached out during cross linking. The degree of swelling was promising with some beads swelling to a degree of 2.5 in phosphate buffer solution pH 5.6. Granules had a drug loading between 81.73 ± 1.53% and 93.30 ± 0.50%. Ketoprofen release from the beads and the granules in PBS pH 7.40 at 37 °C over a period of 6 hours were investigated. The bead formulations were more effective in achieving controlled release and it was noted that the bead formulations that was cross linked for a longer period was more efficient in achieving controlled release. The granules did not form a matrix and were not effective in achieving controlled release. Controlled release of ketoprofen were achieved and the results show potential for chitosan-Kollidon® SR formulations in the future.
Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2008.
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Libros sobre el tema "Chitosan beads"

1

Clark, Roger N. The chiton fauna of the Gulf of California rhodolith beds (with the descriptions of four new species). Wilmington: Delaware Museum of Natural History, 2000.

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Tzu-Yang, Hsien. Synthesis of porous, magnetic chitosan beads and application to cadmium ion adsorption. 1992.

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Hsien, Tzu-Yang. Removal of cadmium ions by porous chitosan beads: Effects of acylation & crosslinking on material properties and adsorption isotherms. 1996.

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Capítulos de libros sobre el tema "Chitosan beads"

1

Dash, Mamoni, Anna Maria Piras y Federica Chiellini. "Chitosan-Based Beads for Controlled Release of Proteins". En Hydrogels, 111–20. Milano: Springer Milan, 2009. http://dx.doi.org/10.1007/978-88-470-1104-5_10.

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Dutta, Joydeep. "Chitosan-Based Composite Beads for Removal of Anionic Dyes". En Sustainable Textiles: Production, Processing, Manufacturing & Chemistry, 47–73. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-2832-1_3.

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Igberase, Ephraim, Peter Ogbemudia Osifo, Tumisang Seodigeng y Ikenna Emeji. "Use of Diethylenetriamine Grafted onto Glyoxal Cross-Linked Chitosan Beads for Efficient Batch System Adsorption". En Enhanced Chitosan Material for Water Treatment, 135–57. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-71722-3_7.

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Igberase, Ephraim, Peter Ogbemudia Osifo, Tumisang Seodigeng y Ikenna Emeji. "Thermodynamics, Kinetics and Desorption Studies of Heavy Metal Ions by Grafted Cross-Linked Chitosan Beads Composites". En Enhanced Chitosan Material for Water Treatment, 25–45. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-71722-3_2.

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Igberase, Ephraim, Peter Ogbemudia Osifo, Tumisang Seodigeng y Ikenna Emeji. "Modelling of Packed Bed Column for the Adsorption of Cu(II) Ions Using Chemically Enhanced Chitosan Beads". En Enhanced Chitosan Material for Water Treatment, 115–34. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-71722-3_6.

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Igberase, Ephraim, Peter Ogbemudia Osifo, Tumisang Seodigeng y Ikenna Emeji. "Investigation into the Adsorption of Cadmium and Lead by Polyaniline Grafted Cross-Linked Chitosan Beads from Aqueous Solution". En Enhanced Chitosan Material for Water Treatment, 71–92. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-71722-3_4.

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Aili, D., W. Arbia y L. Adour. "Treatment of Colored Waters by Beads Chitosan, Extracted from Shrimp Waste". En Proceedings of the Third International Symposium on Materials and Sustainable Development, 492–505. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-89707-3_54.

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Dutta, Joydeep. "Correction to: Chitosan-Based Composite Beads for Removal of Anionic Dyes". En Sustainable Textiles: Production, Processing, Manufacturing & Chemistry, C1—C17. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-2832-1_15.

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Mori, Akihiko, Shin-ichi Tanaka, Naoki Matsumoto y Chuhei Imai. "Vinegar Production in a Bioreactor with Chitosan Beads as Supports of Immobilized Bacteria". En Biochemical Engineering for 2001, 441–43. Tokyo: Springer Japan, 1992. http://dx.doi.org/10.1007/978-4-431-68180-9_116.

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Hansupalak, Nanthiya, Parichart Kitsongsermthon y Ratana Jiraratananon. "Immobilized Flavourzyme on Chitosan Beads for Seasoning Sauce Production: Covalent Binding vs Entrapment". En Contemporary Science of Polymeric Materials, 53–62. Washington, DC: American Chemical Society, 2010. http://dx.doi.org/10.1021/bk-2010-1061.ch004.

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Actas de conferencias sobre el tema "Chitosan beads"

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Marudova, M. G., G. Zsivanovits, I. G. Popchev, I. P. Petrovska, Angelos Angelopoulos y Takis Fildisis. "Preparation and Evaluation of Carrageenan∕Chitosan Multilayer Beads". En ORGANIZED BY THE HELLENIC PHYSICAL SOCIETY WITH THE COOPERATION OF THE PHYSICS DEPARTMENTS OF GREEK UNIVERSITIES: 7th International Conference of the Balkan Physical Union. AIP, 2010. http://dx.doi.org/10.1063/1.3322554.

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Roslan, Fatin Fazrina, Fatin Nur Amirah Mohd Sabri, Noor Hidayah Che Lah, Nur Nabilah Shahidan y Muhammad Ashraf Shahidan. "A study on chitosan macroparticles as potential affinity beads". En MATERIALS CHARACTERIZATION USING X-RAYS AND RELATED TECHNIQUES. Author(s), 2019. http://dx.doi.org/10.1063/1.5089336.

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Rochima, Emma, Safira Utami, Herman Hamdani, Sundoro Yoga Azhary, Danar Praseptiangga, I. Made Joni y Camellia Panatarani. "The dispersion of fine chitosan particles by beads-milling". En THE 1ST INTERNATIONAL CONFERENCE AND EXHIBITION ON POWDER TECHNOLOGY INDONESIA (ICePTi) 2017. Author(s), 2018. http://dx.doi.org/10.1063/1.5021225.

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Panatarani, Camellia, Emma Rochima, Ayunani, Sundoro Yoga y I. Made Joni. "Reinforcement of Carrageenan/Starch Based Bio-Composite by Beads-Milled Chitosan". En 5th International Conference on Food, Agriculture and Natural Resources (FANRes 2019). Paris, France: Atlantis Press, 2020. http://dx.doi.org/10.2991/aer.k.200325.054.

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Simonescu, Claudia Maria. "COPPER REMOVAL FROM SYNTHETIC AQUEOUS SOLUTIONS BY CHEMICALLY MODIFIED BEADS OF CHITOSAN". En 15th International Multidisciplinary Scientific GeoConference SGEM2015. Stef92 Technology, 2011. http://dx.doi.org/10.5593/sgem2015/b51/s20.022.

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Liu, Bingjie, Dongfeng Wang, Haiyan Li, Liyuan Wang y Li Zhang. "As(III) Removal from Aqueous Solution Using a-Fe2O3-impregnated Chitosan Beads". En 2010 International Conference on Digital Manufacturing and Automation (ICDMA). IEEE, 2010. http://dx.doi.org/10.1109/icdma.2010.320.

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Franconetti, Antonio, Dolores Lara-García, Pedro Dominguez-Rodriguez y Francisca Cabrera-Escribano. "Structurally Complexes Aromatic Aldehydes on Knoevenagel Condensation Catalyzed by Chitosan Hydrogel Beads". En The 18th International Electronic Conference on Synthetic Organic Chemistry. Basel, Switzerland: MDPI, 2014. http://dx.doi.org/10.3390/ecsoc-18-a038.

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Zou, Lubin, Hui Liu y Han Zhao. "Immobilized lipase on chitosan beads as catalyst for biodiesel production from Tong oil". En 2011 International Conference on Electrical and Control Engineering (ICECE). IEEE, 2011. http://dx.doi.org/10.1109/iceceng.2011.6058502.

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Villamin, Maria Emma y Yoshitaka Kitamoto. "Facile synthesis and AC characterization of chitosan and iron oxide nanoparticles magnetic beads". En THE IRAGO CONFERENCE 2018: A 360-degree Outlook on Critical Scientific and Technological Challenges for a Sustainable Society. Author(s), 2019. http://dx.doi.org/10.1063/1.5089449.

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Wanchai, Katnanipa y Rattiya Pichon. "Synthesis of Fe3O4@chitosan beads for degradation of sulfanilamide using photo-fenton process". En THE SECOND MATERIALS RESEARCH SOCIETY OF THAILAND INTERNATIONAL CONFERENCE. AIP Publishing, 2020. http://dx.doi.org/10.1063/5.0024113.

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