Journal articles: 'Colloidal hydrogel'

1

Serpe, M. J., J. Kim, and L. A. Lyon. "Colloidal Hydrogel Microlenses." Advanced Materials 16, no. 2 (January 16, 2004): 184–87. http://dx.doi.org/10.1002/adma.200305675.

Full text

APA, Harvard, Vancouver, ISO, and other styles

2

Maikovych, O. V., I. A. Dron, N. M. Bukartyk, O. Yu Bordeniuk, and N. G. Nosova. "Іnvestigation of gel formation peculiarities and properties of hydrogels obtained by the structuring of acrylamide prepolymers." Chemistry, Technology and Application of Substances 4, no. 1 (June 1, 2021): 179–85. http://dx.doi.org/10.23939/ctas2021.01.179.

Full text

Abstract:

The paper represents the results of the investigation of the formation of a polymeric matrix of hydrogel due to the structuring of polyacrylamide using its reactive polymeric derivative – poly-N- (hydroxymethyl) acrylamide. Research determined zones of optimum conditions of synthesis and characterized hydrogel depending on pH of media, the ratio between the concentration of prepolymers, and time of synthesis. The investigation of the reaction mixture showed that the hydrogen index of the synthesis of hydrogels is one of the important factors, which in the design of the polymer framework of hydrogels allows regulating their colloidal chemical properties in a wide range.

APA, Harvard, Vancouver, ISO, and other styles

3

Sahiner, Nurettin. "Colloidal nanocomposite hydrogel particles." Colloid and Polymer Science 285, no. 4 (November 3, 2006): 413–21. http://dx.doi.org/10.1007/s00396-006-1583-7.

Full text

APA, Harvard, Vancouver, ISO, and other styles

4

Sun, Bo, Wenxin Zhang, Yangyang Liu, Min Xue, Lili Qiu, and Zihui Meng. "A Biomass Based Photonic Crystal Hydrogel Made of Bletilla striata Polysaccharide." Biosensors 12, no. 10 (October 8, 2022): 841. http://dx.doi.org/10.3390/bios12100841.

Full text

Abstract:

Bletilla striata is an herb with a good medicinal value whose main active ingredient is Bletilla striata polysaccharide (BSP) in the tuber of Bletilla striata. In this study, a polysaccharide-based semi-interpenetrating network hydrogel was constructed by introducing BSP into polyacrylamide (PAM) hydrogel. The introduction of the BSP chain no only maintains the excellent mechanical properties of PAM, but also endows it with good biocompatibility. By implanting the colloidal crystal array into the above hydrogels, we obtained a novel biomass-based photonic crystal with good stimulus responsiveness that is sensitive to volatile organic compounds (VOCs), especially alcohol vapor. In addition, due to the scavenging ability of BSP to hydroxyl radicals, the photonic crystal hydrogel also has a good response to hydrogen peroxide (H2O2).

APA, Harvard, Vancouver, ISO, and other styles

5

Tang, Wenwei, and Cheng Chen. "Hydrogel-Based Colloidal Photonic Crystal Devices for Glucose Sensing." Polymers 12, no. 3 (March 9, 2020): 625. http://dx.doi.org/10.3390/polym12030625.

Full text

Abstract:

Diabetes, a common epidemic disease, is increasingly hazardous to human health. Monitoring body glucose concentrations for the prevention and therapy of diabetes has become very important. Hydrogel-based responsive photonic crystal (PC) materials are noninvasive options for glucose detection. This article reviews glucose-sensing materials/devices composed of hydrogels and colloidal photonic crystals (CPCs), including the construction of 2D/3D CPCs and 2D/3D hydrogel-based CPCs (HCPCs). The development and mechanisms of glucose-responsive hydrogels and the achieved technologies of HCPC glucose sensors were also concluded. This review concludes by showing a perspective for the future design of CPC glucose biosensors with functional hydrogels.

APA, Harvard, Vancouver, ISO, and other styles

6

Weiler, M., and C. Pacholski. "Soft colloidal lithography." RSC Advances 7, no. 18 (2017): 10688–91. http://dx.doi.org/10.1039/c7ra00338b.

Full text

APA, Harvard, Vancouver, ISO, and other styles

7

Xu, Jia-Yu, Chun-Xiao Yan, Xiao-Chun Hu, Chao Liu, Hua-Min Tang, Chao-Hua Zhou, and Fei Xue. "Study on a Photonic Crystal Hydrogel Material for Chemical Sensing." International Journal of Nanoscience 14, no. 01n02 (February 2015): 1460025. http://dx.doi.org/10.1142/s0219581x14600254.

Full text

Abstract:

There is intense interest in the applications of photonic crystal hydrogel materials for the detection of glucose, metal ions, organophosphates and so on. In this paper, monodisperse polystyrene spheres with diameters between 100 ~ 440 nm were synthesized by emulsion polymerization. Highly charged polystyrene spheres readily self-assembled into crystalline colloidal array because of electrostatic interactions. Photonic crystal hydrogel materials were formed by polymerization of acrylamide hydrogel around the crystalline colloidal arrays of polystyrene spheres. After chemical modification of hydrogel backbone with carboxyl groups, our photonic crystals hydrogel materials are demonstrated to be excellent in response to pH and ionic strength changes.

APA, Harvard, Vancouver, ISO, and other styles

8

Klučáková, Martina. "Effect of Chitosan as Active Bio-colloidal Constituent on the Diffusion of Dyes in Agarose Hydrogel." Gels 9, no. 5 (May 9, 2023): 395. http://dx.doi.org/10.3390/gels9050395.

Full text

Abstract:

Agarose hydrogel was enriched by chitosan as an active substance for the interactions with dyes. Direct blue 1, Sirius red F3B, and Reactive blue 49 were chosen as representative dyes for the study of the effect of their interaction with chitosan on their diffusion in hydrogel. Effective diffusion coefficients were determined and compared with the value obtained for pure agarose hydrogel. Simultaneously, sorption experiments were realized. The sorption ability of enriched hydrogel was several times higher in comparison with pure agarose hydrogel. Determined diffusion coefficients decreased with the addition of chitosan. Their values included the effects of hydrogel pore structure and interactions between chitosan and dyes. Diffusion experiments were realized at pH 3, 7, and 11. The effect of pH on the diffusivity of dyes in pure agarose hydrogel was negligible. Effective diffusion coefficients obtained for hydrogels enriched by chitosan increased gradually with increasing pH value. Electrostatic interactions between amino group of chitosan and sulfonic group of dyes resulted in the formation of zones with a sharp boundary between coloured and transparent hydrogel (mainly at lower pH values). A concentration jump was observed at a given distance from the interface between hydrogel and the donor dye solution.

APA, Harvard, Vancouver, ISO, and other styles

9

Hu, Xiaohong, Lingyun Hao, Huaiqing Wang, Xiaoli Yang, Guojun Zhang, Guoyu Wang, and Xiao Zhang. "Hydrogel Contact Lens for Extended Delivery of Ophthalmic Drugs." International Journal of Polymer Science 2011 (2011): 1–9. http://dx.doi.org/10.1155/2011/814163.

Full text

Abstract:

Soft contact lenses can improve the bioavailability and prolong the residence time of drugs and, therefore, are ideal drug carriers for ophthalmic drug delivery. Hydrogels are the leading materials of soft contact lenses because of their biocompatibility and transparent characteristic. In order to increase the amount of load drug and to control their release at the expected intervals, many strategies are developed to modify the conventional contact lens as well as the novel hydrogel contact lenses that include (i) polymeric hydrogels with controlled hydrophilic/hydrophobic copolymer ratio; (ii) hydrogels for inclusion of drugs in a colloidal structure dispersed in the contact lenses; (iii) ligand-containing hydrogels; (iv) molecularly imprinted polymeric hydrogels; (v) hydrogel with the surface containing multilayer structure for drugs loading and releasing. The advantages and disadvantages of these strategies in modifying or designing hydrogel contact lenses for extended ophthalmic drug delivery are analyzed in this paper.

APA, Harvard, Vancouver, ISO, and other styles

10

Xue, Fei, Zihui Meng, Fengyan Wang, Qiuhong Wang, Min Xue, and Zhibin Xu. "A 2-D photonic crystal hydrogel for selective sensing of glucose." J. Mater. Chem. A 2, no. 25 (2014): 9559–65. http://dx.doi.org/10.1039/c4ta01031k.

Full text

APA, Harvard, Vancouver, ISO, and other styles

11

Wang, Huan, Yuxiao Liu, Zhuoyue Chen, Lingyu Sun, and Yuanjin Zhao. "Anisotropic structural color particles from colloidal phase separation." Science Advances 6, no. 2 (January 2020): eaay1438. http://dx.doi.org/10.1126/sciadv.aay1438.

Full text

Abstract:

Structural color materials have been studied for decades because of their fascinating properties. Effects in this area are the trend to develop functional structural color materials with new components, structures, or morphologies for different applications. In this study, we found that the coassembled graphene oxide (GO) and colloid nanoparticles in droplets could form component phase separations, and thus, previously unknown anisotropic structural color particles (SCPs) with hemispherical colloidal crystal cluster and oblate GO component could be achieved. The anisotropic SCPs, as well as their inverse opal hydrogel derivatives, were endowed with brilliant structural colors and controllable capabilities of fixation, location, orientation, and even responsiveness due to their specific structure, morphology, and components. We have also demonstrated that the anisotropic hydrogel SCPs with these features were ideal candidates for dynamic cell monitoring and sensing. These properties indicate that the anisotropic SCPs and their derivatives have huge potential values in biomedical areas.

APA, Harvard, Vancouver, ISO, and other styles

12

MOHAMMADI, ALIASGHAR, and REGHAN J. HILL. "Dynamics of uncharged colloidal inclusions in polyelectrolyte hydrogels." Journal of Fluid Mechanics 669 (January 14, 2011): 298–327. http://dx.doi.org/10.1017/s0022112010005045.

Full text

Abstract:

We calculate the dynamics of an uncharged colloidal sphere embedded in a quenched polyelectrolyte hydrogel to (i) an oscillatory (optical and magnetic) force, as adopted in classical micro-rheology, and (ii) an oscillatory electric field, as adopted in electrical micro-rheology and electro-acoustics. The hydrogel is modelled as a linearly elastic porous medium with the charge fixed to the skeleton and saturated with a Newtonian electrolyte; and the colloidal inclusion is modelled as a rigid, impenetrable sphere. The dynamic micro-rheological susceptibility, defined as the ratio of the particle displacement to the strength of an applied oscillatory force, depends on the fixed-charge density and ionic strength and is bounded by the limits for incompressible and uncharged, compressible skeletons. Nevertheless, the influences of fixed charge and ionic strength vanish at frequencies above the reciprocal draining time, where the polymer and the electrolyte hydrodynamically couple as a single incompressible phase. Generally, the effects of fixed charge and ionic strength are small compared with, for example, the influences of polymer slip at the particle surface. The electrical susceptibility, defined as the ratio of the particle displacement to the strength of an applied oscillatory electric field, is directly influenced by charge at all frequencies, irrespective of skeleton compressibility. At low frequencies, polymer charge modulates the driving (electro-osmotic) and restoring (electrostatically enhanced elastic) forces, whereas charge has no influence on the restoring force at high frequencies where dilational strain is suppressed by hydrodynamic coupling with the electrolyte. In striking contrast to charged inclusions in uncharged hydrogels (Wang & Hill, J. Fluid Mech., vol. 640, 2009, pp. 357–400), the electrical susceptibility at high frequencies is independent of electrolyte concentration. Rather, the dynamics primarily reflect the elastic modulus, charge and hydrodynamic permeability, with a relatively weak dependence on particle size. Interestingly, the dynamic mobility in the zero-momentum reference frame, which is central to the electro-acoustic response, is qualitatively different from the dynamic mobility in the skeleton-fixed reference frame. Finally, we propose a phenomenological harmonic-oscillator model to address – in an approximate manner – the dynamics of charged particles in charged hydrogels. This shows that particle dynamics at low frequencies are dominated by particle charge, whereas high-frequency dynamics are dominated by hydrogel charge.

APA, Harvard, Vancouver, ISO, and other styles

13

Qi, Dashan, Haowei Zhu, Yingjie Kong, and Qingming Shen. "Injectable Nanomedicine–Hydrogel for NIR Light Photothermal–Chemo Combination Therapy of Tumor." Polymers 14, no. 24 (December 18, 2022): 5547. http://dx.doi.org/10.3390/polym14245547.

Full text

Abstract:

Traditional hydrogels have drawbacks such as surgical implantation, large wound surfaces, and uncontrollable drug release during tumor treatment. In this paper, targeted nanomedicine has been combined with injectable hydrogel for photothermal–chemotherapy combination therapy. First, targeted nanomedicine (ICG—MTX) was fabricated by combining near-infrared (NIR) photothermal reagents (ICG) and chemotherapy drugs (MTX). The ICG—MTX was then mixed with the hydrogel precursor and radical initiator to obtain an injectable hydrogel precursor solution. Under the irradiation of NIR light, the precursor solution could release alkyl radicals, which promote the transition of the precursor solution from a liquid to a colloidal state. As a result, the nanomedicine could effectively remain at the site of the tumor and continue to be released from the hydrogel. Due to the targeted nature of MTX, the released ICG—MTX could target tumor cells and improve the accuracy of photothermal–chemo combination therapy. The results indicated that the injectable nanomedicine–hydrogel system has a favorable therapeutic effect on tumors.

APA, Harvard, Vancouver, ISO, and other styles

14

Tajdar, Yasir, Sakshi Singh, Ankit Raj, Ayush Raj, and Vibhuti Bhushan. "Effect of silver colloid dressing over conventional dressings in diabetic foot ulcer: A prospective study." Turkish Journal of Surgery 40, no. 1 (March 1, 2024): 28–35. http://dx.doi.org/10.47717/turkjsurg.2024.6168.

Full text

Abstract:

Objective: Topical silver treatments and silver dressings are increasingly being utilized for the local treatment of wounds; nevertheless, the evidence for their usefulness is unclear. The aim of this study was to investigate the impact of conventional dressings and silver colloid dressing on diabetic foot ulcers (DFU) with and without compression therapy. Material and Methods: This prospective, double-blind experiment included 50 patients with non-ischemic DFUs, split into two groups of 25 patients each. The study was conducted for a period of six months. The primary endpoint was to evaluate the entire epithelialization (total healing) of all ulcers on the study leg. Results: The ulcer area significantly decreased in the colloidal silver group (67.77 ± 17.82%) compared to the conventional saline group (21.70 ± 23.52%). When compared to the conventional group, the colloidal silver group required considerably fewer days to reach the endpoint (23.15 ± 8.15 days vs. 48.35 ± 18.07 days), and by day 14, ulcer area reduction (from 100%) was greater (48% in the silver group vs. 89.69% in the conventional group). Conclusion: In managing DFUs, unstructured hydrogel wound dressings using silver colloids based on ionic silver are more effective than regular saline dressings since they heal wounds more quickly in fewer days while also drastically reducing ulcer areas over time.

APA, Harvard, Vancouver, ISO, and other styles

15

Zheng, Da, Haihua Chen, Shuai Zhang, Jing Wang, and Zhong-Ze Gu. "Crystallization of colloidal crystal on hydrogel surface." Colloids and Surfaces A: Physicochemical and Engineering Aspects 292, no. 1 (January 2007): 63–68. http://dx.doi.org/10.1016/j.colsurfa.2006.06.003.

Full text

APA, Harvard, Vancouver, ISO, and other styles

16

Fernandes, Gregory E., Daniel J. Beltran-Villegas, and Michael A. Bevan. "Interfacial Colloidal Crystallization via Tunable Hydrogel Depletants." Langmuir 24, no. 19 (October 7, 2008): 10776–85. http://dx.doi.org/10.1021/la802025d.

Full text

APA, Harvard, Vancouver, ISO, and other styles

17

Meng, Zhi-Jun, Jing Zhang, Xu Deng, Ji Liu, Ziyi Yu, and Chris Abell. "Bioinspired hydrogel microfibres colour-encoded with colloidal crystals." Materials Horizons 6, no. 9 (2019): 1938–43. http://dx.doi.org/10.1039/c9mh00528e.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Smirnov, Michael A., Vitaly K. Vorobiov, Veronika S. Fedotova, Maria P. Sokolova, Natalya V. Bobrova, Nikolay N. Smirnov, and Oleg V. Borisov. "A Polyelectrolyte Colloidal Brush Based on Cellulose: Perspectives for Future Applications." Polymers 15, no. 23 (November 25, 2023): 4526. http://dx.doi.org/10.3390/polym15234526.

Full text

Abstract:

This feature article is devoted to the evaluation of different techniques for producing colloidal polyelectrolyte brushes (CPEBs) based on cellulose nanofibers modified with grafted polyacrylates. The paper also reviews the potential applications of these CPEBs in designing electrode materials and as reinforcing additives. Additionally, we discuss our own perspectives on investigating composites with CPEBs. Herein, polyacrylic acid (PAA) was grafted onto the surface of cellulose nanofibers (CNFs) employing a “grafting from” approach. The effect of the PAA shell on the morphological structure of a composite with polypyrrole (PPy) was investigated. The performance of as-obtained CNF-PAA/PPy as organic electrode material for supercapacitors was examined. Furthermore, this research highlights the ability of CNF-PAA filler to act as an additional crosslinker forming a physical sub-network due to the hydrogen bond interaction inside chemically crosslinked polyacrylamide (PAAm) hydrogels. The enhancement of the mechanical properties of the material with a concomitant decrease in its swelling ratio compared to a pristine PAAm hydrogel was observed. The findings were compared with the recent theoretical foundation pertaining to other similar materials.

APA, Harvard, Vancouver, ISO, and other styles

19

Solanki, Dharmendra, Priyanka Yadav, Anjali Soni, and Ritu Jaiswal. "HYDROGEL- A REVIEW." International Journal of Pharma Professional’s Research (IJPPR) 14, no. 1 (February 3, 2023): 131–39. http://dx.doi.org/10.48165/ijppronline.2023.14112.

Full text

Abstract:

Hydrogel’s may be defined as a network of polymer chains that are hydrophilic, water insoluble sometimes found as a colloidal gel in which water is a dispersion medium. Their ability to absorbed water is because of its cross linking network structure which is formed by polymer bearing hydrophilic groups. Hydrogel’s are insoluble due to the presence of chemical and physical cross-links Such as entanglements. It is also respond to the fluctuation of environmental stimuli (ionic strength, temperature. pH, presence of enzyme etc.) and swell or shrink accordingly in the swollen state they are soft and rubbery resembling the living tissue exhibiting excellent biocompatibility Hydrogel are commonly used in clinical practice and experimental medicine for a wide range of applications, including food additives, Tissue engineering, regenerative medicines, Pharmaceuticals drug delivery devices and membranes for biosensors etc.

APA, Harvard, Vancouver, ISO, and other styles

20

Ma, Yue, Peiyan He, Wanli Xie, Qiang Zhang, Weiling Yin, Jianming Pan, Miao Wang, Xin Zhao, and Guoqing Pan. "Dynamic Colloidal Photonic Crystal Hydrogels with Self-Recovery and Injectability." Research 2021 (March 30, 2021): 1–11. http://dx.doi.org/10.34133/2021/9565402.

Full text

Abstract:

Simulation of self-recovery and diversity of natural photonic crystal (PC) structures remain great challenges for artificial PC materials. Motivated by the dynamic characteristics of PC nanostructures, here, we present a new strategy for the design of hydrogel-based artificial PC materials with reversible interactions in the periodic nanostructures. The dynamic PC hydrogels, derived from self-assembled microgel colloidal crystals, were tactfully constructed by reversible crosslinking of adjacent microgels in the ordered structure via phenylboronate covalent chemistry. As proof of concept, three types of dynamic colloidal PC hydrogels with different structural colors were prepared. All the hydrogels showed perfect self-healing ability against physical damage. Moreover, dynamic crosslinking within the microgel crystals enabled shear-thinning injection of the PC hydrogels through a syringe (indicating injectability or printability), followed by rapid recovery of the structural colors. In short, in addition to the great significance in biomimicry of self-healing function of natural PC materials, our work provides a facile strategy for the construction of diversified artificial PC materials for different applications such as chem-/biosensing, counterfeit prevention, optical display, and energy conversion.

APA, Harvard, Vancouver, ISO, and other styles

21

Kuriakose, Naveen, Pallavi Bapat, Harriet Lindsay, and John Texter. "Reversible Colloidal Crystallization." MRS Advances 5, no. 40-41 (2020): 2111–19. http://dx.doi.org/10.1557/adv.2020.286.

Full text

Abstract:

AbstractWe report 3D colloidal self-assembly (crystallization) of poly(ionic liquid) latexes to produce crystals that exhibit reversible melting and recrystallization in water, due to “classical” interparticle interactions, typical of multifunctional polymers. These new materials are derived from an ionic liquid monomer that is polymerized at room temperature by redox-initiated polymerization. Particle synthesis, self-assembly, thermal properties, and introductory light diffraction effects are reported with a focus on melting. These crystals are distinguishable from classical colloidal crystalline arrays, and are the first such crystals to exhibit thermal melting. This new hydrogel offers promise for engineering large volume production of photonic crystals active in the visible and proximal spectral regions, by crystallization from suspension (solution), characteristic of most useful chemical compounds.

APA, Harvard, Vancouver, ISO, and other styles

22

Zhang, Xiao, Pengyu Wei, Zhengyang Yang, Yishan Liu, Kairui Yang, Yuhao Cheng, Hongwei Yao, and Zhongtao Zhang. "Current Progress and Outlook of Nano-Based Hydrogel Dressings for Wound Healing." Pharmaceutics 15, no. 1 (December 26, 2022): 68. http://dx.doi.org/10.3390/pharmaceutics15010068.

Full text

Abstract:

Wound dressing is an important tool for wound management. Designing wound dressings by combining various novel materials and drugs to optimize the peri-wound environment and promote wound healing is a novel concept. Hydrogels feature good ductility, high water content, and favorable oxygen transport, which makes them become some of the most promising materials for wound dressings. In addition, nanomaterials exhibit superior biodegradability, biocompatibility, and colloidal stability in wound healing and can play a role in promoting healing through their nanoscale properties or as carriers of other drugs. By combining the advantages of both technologies, several outstanding and efficient wound dressings have been developed. In this paper, we classify nano-based hydrogel dressings into four categories: hydrogel dressings loaded with a nanoantibacterial drug; hydrogel dressings loaded with oxygen-delivering nanomedicines; hydrogel dressings loaded with nanonucleic acid drugs; and hydrogel dressings loaded with other nanodelivered drugs. The design ideas, advantages, and challenges of these nano-based hydrogel wound dressings are reviewed and analyzed. Finally, we envisaged possible future directions for wound dressings in the context of relevant scientific and technological advances, which we hope will inform further research in wound management.

APA, Harvard, Vancouver, ISO, and other styles

23

Piccone, Ashley. "Mesogels control volume to explore the glass transition." Scilight 2022, no. 14 (April 8, 2022): 141102. http://dx.doi.org/10.1063/10.0010112.

Full text

APA, Harvard, Vancouver, ISO, and other styles

24

Hill, Reghan J. "Steady electrodiffusion in hydrogel-colloid composites: macroscale properties from microscale electrokinetics." Anais da Academia Brasileira de Ciências 82, no. 1 (March 2010): 69–86. http://dx.doi.org/10.1590/s0001-37652010000100007.

Full text

Abstract:

A rigorous microscale electrokinetic model for hydrogel-colloid composites is adopted to compute macroscale profiles of electrolyte concentration, electrostatic potential, and hydrostatic pressure across membranes that separate electrolytes with different concentrations. The membranes are uncharged polymeric hydrogels in which charged spherical colloidal particles are immobilized and randomly dispersed with a low solid volume fraction. Bulk membrane characteristics and performance are calculated from a continuum microscale electrokinetic model (Hill 2006b, c). The computations undertaken in this paper quantify the streaming and membrane potentials. For the membrane potential, increasing the volume fraction of negatively charged inclusions decreases the differential electrostatic potential across the membrane under conditions where there is zero convective flow and zero electrical current. With low electrolyte concentration and highly charged nanoparticles, the membrane potential is very sensitive to the particle volume fraction. Accordingly, the membrane potential - and changes brought about by the inclusion size, charge and concentration - could be a useful experimental diagnostic to complement more recent applications of the microscale electrokinetic model for electrical microrheology and electroacoustics (Hill and Ostoja-Starzewski 2008, Wang and Hill 2008).

APA, Harvard, Vancouver, ISO, and other styles

25

Völlmecke, Katharina, Rowshon Afroz, Sascha Bierbach, Lee Josephine Brenker, Sebastian Frücht, Alexandra Glass, Ryland Giebelhaus, et al. "Hydrogel-Based Biosensors." Gels 8, no. 12 (November 25, 2022): 768. http://dx.doi.org/10.3390/gels8120768.

Full text

Abstract:

There is an increasing interest in sensing applications for a variety of analytes in aqueous environments, as conventional methods do not work reliably under humid conditions or they require complex equipment with experienced operators. Hydrogel sensors are easy to fabricate, are incredibly sensitive, and have broad dynamic ranges. Experiments on their robustness, reliability, and reusability have indicated the possible long-term applications of these systems in a variety of fields, including disease diagnosis, detection of pharmaceuticals, and in environmental testing. It is possible to produce hydrogels, which, upon sensing a specific analyte, can adsorb it onto their 3D-structure and can therefore be used to remove them from a given environment. High specificity can be obtained by using molecularly imprinted polymers. Typical detection principles involve optical methods including fluorescence and chemiluminescence, and volume changes in colloidal photonic crystals, as well as electrochemical methods. Here, we explore the current research utilizing hydrogel-based sensors in three main areas: (1) biomedical applications, (2) for detecting and quantifying pharmaceuticals of interest, and (3) detecting and quantifying environmental contaminants in aqueous environments.

APA, Harvard, Vancouver, ISO, and other styles

26

Rüter, Axel, Stefan Kuczera, Luigi Gentile, and Ulf Olsson. "Arrested dynamics in a model peptide hydrogel system." Soft Matter 16, no. 11 (2020): 2642–51. http://dx.doi.org/10.1039/c9sm02244a.

Full text

APA, Harvard, Vancouver, ISO, and other styles

27

Salahuddin, Bidita, Shazed Aziz, Shuai Gao, Md Shahriar A. Hossain, Motasim Billah, Zhonghua Zhu, and Nasim Amiralian. "Magnetic Hydrogel Composite for Wastewater Treatment." Polymers 14, no. 23 (November 22, 2022): 5074. http://dx.doi.org/10.3390/polym14235074.

Full text

Abstract:

Nanocomposite hydrogels are highly porous colloidal structures with a high adsorption capacity, making them promising materials for wastewater treatment. In particular, magnetic nanoparticle (MNP) incorporated hydrogels are an excellent adsorbent for aquatic pollutants. An added advantage is that, with the application of an external magnetic field, magnetic hydrogels can be collected back from the wastewater system. However, magnetic hydrogels are quite brittle and structurally unstable under compact conditions such as in fixed-bed adsorption columns. To address this issue, this study demonstrates a unique hydrogel composite bead structure, providing a good adsorption capacity and superior compressive stress tolerance due to the presence of hollow cores within the beads. The gel beads contain alginate polymer as the matrix and MNP-decorated cellulose nanofibres (CNF) as the reinforcing agent. The MNPs within the gel provide active adsorption functionality, while CNF provide a good stress transfer phenomenon when the beads are under compressive stress. Their adsorption performance is evaluated in a red mud solution for pollutant adsorption. Composite gel beads have shown high performance in adsorbing metal (aluminium, potassium, selenium, sodium, and vanadium) and non-metal (sulphur) contaminations. This novel hybrid hydrogel could be a promising alternative to the conventionally used toxic adsorbent, providing environmentally friendly operational benefits.

APA, Harvard, Vancouver, ISO, and other styles

28

You, Aimei, Yuhua Cao, and Guangqun Cao. "Facile fabrication of a magnetically assembled colloidal photonic crystal film via radical polymerization." RSC Advances 5, no. 114 (2015): 93945–50. http://dx.doi.org/10.1039/c5ra13900g.

Full text

Abstract:

A facile, economical and practical technique to fabricate a magnetically assembled colloidal photonic crystal in a polyacrylamide hydrogel matrix was demonstrated by an instant radical polymerization.

APA, Harvard, Vancouver, ISO, and other styles

29

He, Gang, Sheng Chen, Yunjun Xu, Zhaohua Miao, Yan Ma, Haisheng Qian, Yang Lu, and Zhengbao Zha. "Charge reversal induced colloidal hydrogel acts as a multi-stimuli responsive drug delivery platform for synergistic cancer therapy." Materials Horizons 6, no. 4 (2019): 711–16. http://dx.doi.org/10.1039/c9mh00020h.

Full text

Abstract:

A charge reversal induced colloidal hydrogel composed of amphoteric gelatin nanoparticles (Gela NPs) and melanin-like polydopamine nanoparticles (PDA NPs) was developed for synergistic cancer therapy.

APA, Harvard, Vancouver, ISO, and other styles

30

Burdette, Mary K., Haley W. Jones, Yuriy Bandera, and Stephen H. Foulger. "X-ray radioluminescent hydrogel stabilized crystalline colloidal arrays." Optical Materials Express 9, no. 3 (February 21, 2019): 1416. http://dx.doi.org/10.1364/ome.9.001416.

Full text

APA, Harvard, Vancouver, ISO, and other styles

31

Debord, J. D., S. Eustis, S. Byul Debord, M. T. Lofye, and L. A. Lyon. "Color-Tunable Colloidal Crystals from Soft Hydrogel Nanoparticles." Advanced Materials 14, no. 9 (May 3, 2002): 658–62. http://dx.doi.org/10.1002/1521-4095(20020503)14:9<658::aid-adma658>3.0.co;2-3.

Full text

APA, Harvard, Vancouver, ISO, and other styles

32

Abrahamsson, Christoffer, Lars Nordstierna, Johan Bergenholtz, Annika Altskär, and Magnus Nydén. "Magnetically induced structural anisotropy in binary colloidal gels and its effect on diffusion and pressure driven permeability." Soft Matter 10, no. 24 (2014): 4403–12. http://dx.doi.org/10.1039/c4sm00315b.

Full text

APA, Harvard, Vancouver, ISO, and other styles

33

Men, Dandan, Honghua Zhang, Lifeng Hang, Dilong Liu, Xinyang Li, Weiping Cai, Qihua Xiong, and Yue Li. "Optical sensor based on hydrogel films with 2D colloidal arrays attached on both the surfaces: anti-curling performance and enhanced optical diffraction intensity." Journal of Materials Chemistry C 3, no. 15 (2015): 3659–65. http://dx.doi.org/10.1039/c5tc00174a.

Full text

Abstract:

An interesting strategy to create free standing hydrogel composite films with colloidal monolayers attached on both the surfaces, which could act as visualizing sensors with high diffraction intensity, is developed.

APA, Harvard, Vancouver, ISO, and other styles

34

Park, H., K. H. Lee, Y. B. Kim, S. B. Ambade, S. H. Noh, W. Eom, J. Y. Hwang, W. J. Lee, J. Huang, and T. H. Han. "Dynamic assembly of liquid crystalline graphene oxide gel fibers for ion transport." Science Advances 4, no. 11 (November 2018): eaau2104. http://dx.doi.org/10.1126/sciadv.aau2104.

Full text

Abstract:

Colloidal dispersions with liquid crystallinity hold great promise for fabricating their superstructures. As an example, when graphene oxide (GO) sheets are assembled in the liquid crystalline state, they can turn into ordered macroscopic forms of GO such as fibers via the wet spinning process. Here, we report that by reinforcing intersheet interactions, GO liquid crystals (LCs) turn into mechanically robust hydrogels that can be readily drawn into highly aligned fibrillar structures. GO hydrogel fibers with highly aligned sheets (orientation factor, f = 0.71) exhibit more than twice the ionic conductivity compared to those with partially aligned structures (f = 0.01). The hierarchically interconnected two-dimensional nanochannels within these neatly aligned GOLC hydrogel fibers may facilitate controlled transport of charge carriers and could be potentially explored as cables for interconnecting biosystems and/or human-made devices.

APA, Harvard, Vancouver, ISO, and other styles

35

Shewan, Heather M., Gleb E. Yakubov, Mauricio R. Bonilla, and Jason R. Stokes. "Viscoelasticity of non-colloidal hydrogel particle suspensions at the liquid–solid transition." Soft Matter 17, no. 19 (2021): 5073–83. http://dx.doi.org/10.1039/d0sm01624a.

Full text

Abstract:

The liquid–solid transition occurs across a viscoelastic–liquid regime for non-colloidal, polydisperse, frictional soft hydrogel particle suspensions converse to the discrete transition expected for these suspensions of large particles.

APA, Harvard, Vancouver, ISO, and other styles

36

Kanai, Toshimitsu, Naoto Kobayashi, and Hiroyuki Tajima. "Enhanced linear thermosensitivity of gel-immobilized colloidal photonic crystal film bound on glass substrate." Materials Advances 2, no. 8 (2021): 2600–2603. http://dx.doi.org/10.1039/d1ma00041a.

Full text

Abstract:

The linear thermosensitivity of colloidal crystals immobilized in a copolymer hydrogel film composed of PNIPAM and PNMAM could be enhanced by chemically binding them on a glass substrate using a silane coupling agent.

APA, Harvard, Vancouver, ISO, and other styles

37

Qin, Junjie, Bohua Dong, Xue Li, Jiwei Han, Rongjie Gao, Ge Su, Lixin Cao, and Wei Wang. "Fabrication of intelligent photonic crystal hydrogel sensors for selective detection of trace mercury ions in seawater." Journal of Materials Chemistry C 5, no. 33 (2017): 8482–88. http://dx.doi.org/10.1039/c7tc02140b.

Full text

Abstract:

Hydrogel thin films with embedded 3-D ordered colloidal nanoparticle arrays are fabricated and functionalized with spatially distributed thiol groups for high-sensitive and selective detection of trace Hg²⁺ ions in seawater.

APA, Harvard, Vancouver, ISO, and other styles

38

Chen, Dong, Esther Amstad, Chun-Xia Zhao, Liheng Cai, Jing Fan, Qiushui Chen, Mingtan Hai, et al. "Biocompatible Amphiphilic Hydrogel–Solid Dimer Particles as Colloidal Surfactants." ACS Nano 11, no. 12 (December 15, 2017): 11978–85. http://dx.doi.org/10.1021/acsnano.7b03110.

Full text

APA, Harvard, Vancouver, ISO, and other styles

39

Shabaniverki, Soheila, and Jaime J. Juárez. "Characterizing gelatin hydrogel viscoelasticity with diffusing colloidal probe microscopy." Journal of Colloid and Interface Science 497 (July 2017): 73–82. http://dx.doi.org/10.1016/j.jcis.2017.02.057.

Full text

APA, Harvard, Vancouver, ISO, and other styles

40

Apkarian, Robert P., Elizabeth R. Wright, Victor A. Seredyuk, Susan Eustis, L. Andrew Lyon, Vincent P. Conticello, and Fredric M. Menger. "In-Lens Cryo-High Resolution Scanning Electron Microscopy: Methodologies for Molecular Imaging of Self-Assembled Organic Hydrogels." Microscopy and Microanalysis 9, no. 4 (August 2003): 286–95. http://dx.doi.org/10.1017/s1431927603030551.

Full text

Abstract:

The micro- and nanoarchitectures of water-swollen hydrogels were routinely analyzed in three dimensions at very high resolution by two cryopreparation methods that provide stable low-temperature specimens for in-lens high magnification recordings. Gemini surfactants (gS), poly-N-isopropylacrylamides (p-NIP Am), and elastin-mimetic di- (db-E) and triblock (tb-E) copolymer proteins that form hydrogels have been routinely analyzed to the sub-10-nm level in a single day. After they were quench or high pressure frozen, samples in bulk planchets were subsequently chromium coated and observed at low temperature in an in-lens field emission SEM. Pre-equilibrated planchets (4–40°C) that hold 5–10 μl of hydrogel facilitate dynamic morphological studies above and below their transition temperatures. Rapidly frozen samples were fractured under liquid nitrogen, low-temperature metal coated, and observed in-lens to assess the dispersion characteristics of micelles and fragile colloidal assemblies within bulk frozen water. Utilizing the same planchet freezing system, the cryoetch-HRSEM technique removed bulk frozen water from the hydrogel matrix by low-temperature, high-vacuum sublimation. The remaining frozen solid-state sample faithfully represented the hydrogel matrix. Cryo- and cryoetch-HRSEM provided vast vistas of hydrogels at low and intermediate magnifications whereas high magnification recordings and anaglyphs (stereo images) provided a three-dimensional prospective and measurements on a molecular level.

APA, Harvard, Vancouver, ISO, and other styles

41

Hu, Hai Bo, Qian Wang Chen, Ran Li, Xiang Kai Kong, and Jian Chen. "Exploration of the Structures of the Magnetically Induced Self-Assembly Photonic Crystals in a Solidified Polymer Matrix." Advanced Materials Research 634-638 (January 2013): 2324–31. http://dx.doi.org/10.4028/www.scientific.net/amr.634-638.2324.

Full text

Abstract:

The carbon-encapsulated superparamagnetic colloidal nanoparticles (SCNps) were rigidized into soft solids by embedding the SCNps into polyacrylamide hydrogel matrixes under the induction of an external magnetic field. Stabilized by the balance of attractive (magnetic) and repulsive (electrostatic) forces, the SCNps form one-dimension photonic crystal structures along the direction of the external magnetic field and further the structures are frozen into the solidified polymer matrix. The polymer matrix embedded one-dimension photonic crystal structures can strongly diffract visible light and present brilliant color in the light. This novel and soft solid polymer matrix that could be shaped and sliced not only paves a new avenue for develop novel magnetic-responsive photonic crystal materials and devices, but also provides a method to observe the magnetic-induced self-assembly structures of the SCNps in media such as polyacrylamide hydrogel matrixs as a result of the ordered structures frozen into the polyacrylamide hydrogel matrixs. So we can reveal the relationship between their structure and color, and furthermore permit a systematic exploration on magnetically induced self-assembling dynamics, colloidal crystallography which have important significance in the large-scale industrial production in the future.

APA, Harvard, Vancouver, ISO, and other styles

42

Martin, Steve, Hanqing Wang, Laura Hartmann, Tilo Pompe, and Stephan Schmidt. "Quantification of protein–materials interaction by soft colloidal probe spectroscopy." Physical Chemistry Chemical Physics 17, no. 5 (2015): 3014–18. http://dx.doi.org/10.1039/c4cp05484a.

Full text

APA, Harvard, Vancouver, ISO, and other styles

43

Paze, Aigars, Sanita Vitolina, Rudolfs Berzins, Janis Rizhikovs, Raimonds Makars, Daniela Godina, and Arturs Teresko. "The Study of Betulin Particles Containing Hydrogels Prepared by Antisolvent Precipitation." Key Engineering Materials 933 (October 17, 2022): 139–46. http://dx.doi.org/10.4028/p-rhk0o3.

Full text

Abstract:

The aim of the study was to investigate the effect of process parameters on the production of hydrogels with antisolvent precipitation using unpurified (UB) and purified (PB) birch outer bark betulin powder samples. Experimental activities are focused on the production of hydrogels using concentration of colloidal dispersions with filtration of UB or PB sample particles obtained by antisolvent precipitation method varying the dilution of saturated (at boiling temperature) ethanol solutions with different water content. During the study the maximum solubility in ethanol at boiling point of PB (22.0 g/L) and UB (55.0 g/L) was determined. For obtaining gel with the highest liquid content (absorption capacity 37.45 g per 1 g of dry matter) from PB by antisolvent precipitation the optimal saturated ethanol solution dilution with water was 12.5 vol%. In the case of UB hydrogel, by dilution of ethanol from 25 to 10 vol%, a gradual decrease of hydrogel dry matter yield and a simultaneous increase of the filtrate dry matter yield can be observed, which is related with leaching of the particles through the filter paper together with a solution and form a colloidal suspension of particles. For obtaining gels with high liquid content from UB the optimal saturated ethanol solution dilution with water was in the range from 20.0 to 12.5 vol% (absorption capacity in average 18 g per 1 g of dry matter). Comparing the chemical compositions of the raw materials and dry matter of hydrogels in the case of PB composition remains quite similar while in UB dry matter composition the betulin content increased from 52 to even 69 wt%. PB at the optimal dilution of 12.5 vol% of ethanol managed to achieve average particle size - 231.7 nm and with UB in the optimal dilution range from 20 to 12.5 vol% the range of average particle size was from 304.7 to 189.8 nm.

APA, Harvard, Vancouver, ISO, and other styles

44

Hassan, Abeer S., and Ghareb M. Soliman. "Rutin Nanocrystals with Enhanced Anti-Inflammatory Activity: Preparation and Ex Vivo/In Vivo Evaluation in an Inflammatory Rat Model." Pharmaceutics 14, no. 12 (December 6, 2022): 2727. http://dx.doi.org/10.3390/pharmaceutics14122727.

Full text

Abstract:

Rutin is a polyphenolic flavonoid with an interestingly wide therapeutic spectrum. However, its clinical benefits are limited by its poor aqueous solubility and low bioavailability. In an attempt to overcome these limitations, rutin nanocrystals were prepared using various stabilizers including nonionic surfactants and nonionic polymers. The nanocrystals were evaluated for particle size, zeta potential, drug entrapment efficiency, morphology, colloidal stability, rutin photostability, dissolution rate, and saturation solubility. The selected nanocrystal formulation was dispersed in a hydrogel base and the drug release kinetics and permeability through mouse skin were characterized. Rutin’s anti-inflammatory efficacy was studied in a carrageenan-induced rat paw edema model. The nanocrystals had a size in the range of around 270–500 nm and a polydispersity index of around 0.3–0.5. Nanocrystals stabilized by hydroxypropyl beta-cyclodextrin (HP-β-CD) had the smallest particle size, highest drug entrapment efficiency, best colloidal stability, and highest drug photostability. Nanocrystals had around a 102- to 202-fold and 2.3- to 6.7-fold increase in the drug aqueous solubility and dissolution rate, respectively, depending on the type of stabilizer. HP-β-CD nanocrystals hydrogel had a significantly higher percent of drug released and permeated through the mouse skin compared with the free drug hydrogel. The cumulative drug amount permeated through the skin was 2.5-fold higher than that of the free drug hydrogel. In vivo studies showed that HP-β-CD-stabilized rutin nanocrystals hydrogel had significantly higher edema inhibition compared with the free drug hydrogel and commercial diclofenac sodium gel. These results highlight the potential of HP-β-CD-stabilized nanocrystals as a promising approach to enhance drug solubility, dissolution rate, and anti-inflammatory properties.

APA, Harvard, Vancouver, ISO, and other styles

45

Wu, Yuchao, Darshil U. Shah, Chenyan Liu, Ziyi Yu, Ji Liu, Xiaohe Ren, Matthew J. Rowland, Chris Abell, Michael H. Ramage, and Oren A. Scherman. "Bioinspired supramolecular fibers drawn from a multiphase self-assembled hydrogel." Proceedings of the National Academy of Sciences 114, no. 31 (July 10, 2017): 8163–68. http://dx.doi.org/10.1073/pnas.1705380114.

Full text

Abstract:

Inspired by biological systems, we report a supramolecular polymer–colloidal hydrogel (SPCH) composed of 98 wt % water that can be readily drawn into uniform (∼6-μm thick) “supramolecular fibers” at room temperature. Functionalized polymer-grafted silica nanoparticles, a semicrystalline hydroxyethyl cellulose derivative, and cucurbit[8]uril undergo aqueous self-assembly at multiple length scales to form the SPCH facilitated by host–guest interactions at the molecular level and nanofibril formation at colloidal-length scale. The fibers exhibit a unique combination of stiffness and high damping capacity (60–70%), the latter exceeding that of even biological silks and cellulose-based viscose rayon. The remarkable damping performance of the hierarchically structured fibers is proposed to arise from the complex combination and interactions of “hard” and “soft” phases within the SPCH and its constituents. SPCH represents a class of hybrid supramolecular composites, opening a window into fiber technology through low-energy manufacturing.

APA, Harvard, Vancouver, ISO, and other styles

46

Meng, Guangnan, Vinothan N. Manoharan, and Adeline Perro. "Core–shell colloidal particles with dynamically tunable scattering properties." Soft Matter 13, no. 37 (2017): 6293–96. http://dx.doi.org/10.1039/c7sm01740e.

Full text

Abstract:

Polystyrene-hydrogel core–shell particles exhibiting a transition from Rayleigh to Mie scattering are created. Optical measurements show that the transition is controlled by varying temperature or ionic strength. Such core–shell particles may find use as optical switches or optical filters with tunable opacity.

APA, Harvard, Vancouver, ISO, and other styles

47

Wang, Zhe, Min Xue, Herong Zhang, Zihui Meng, Kenneth J. Shea, Lili Qiu, Tiantian Ji, and Tengsheng Xie. "Self-assembly of a nano hydrogel colloidal array for the sensing of humidity." RSC Advances 8, no. 18 (2018): 9963–69. http://dx.doi.org/10.1039/c7ra12661a.

Full text

APA, Harvard, Vancouver, ISO, and other styles

48

Malekmohammadi, Samira, Negar Sedghi Aminabad, Amin Sabzi, Amir Zarebkohan, Mehdi Razavi, Massoud Vosough, Mahdi Bodaghi, and Hajar Maleki. "Smart and Biomimetic 3D and 4D Printed Composite Hydrogels: Opportunities for Different Biomedical Applications." Biomedicines 9, no. 11 (October 26, 2021): 1537. http://dx.doi.org/10.3390/biomedicines9111537.

Full text

Abstract:

In recent years, smart/stimuli-responsive hydrogels have drawn tremendous attention for their varied applications, mainly in the biomedical field. These hydrogels are derived from different natural and synthetic polymers but are also composite with various organic and nano-organic fillers. The basic functions of smart hydrogels rely on their ability to change behavior; functions include mechanical, swelling, shaping, hydrophilicity, and bioactivity in response to external stimuli such as temperature, pH, magnetic field, electromagnetic radiation, and biological molecules. Depending on the final applications, smart hydrogels can be processed in different geometries and modalities to meet the complicated situations in biological media, namely, injectable hydrogels (following the sol-gel transition), colloidal nano and microgels, and three dimensional (3D) printed gel constructs. In recent decades smart hydrogels have opened a new horizon for scientists to fabricate biomimetic customized biomaterials for tissue engineering, cancer therapy, wound dressing, soft robotic actuators, and controlled release of bioactive substances/drugs. Remarkably, 4D bioprinting, a newly emerged technology/concept, aims to rationally design 3D patterned biological matrices from synthesized hydrogel-based inks with the ability to change structure under stimuli. This technology has enlarged the applicability of engineered smart hydrogels and hydrogel composites in biomedical fields. This paper aims to review stimuli-responsive hydrogels according to the kinds of external changes and t recent applications in biomedical and 4D bioprinting.

APA, Harvard, Vancouver, ISO, and other styles

49

Mora, Nestor Lopez, Yue Gao, M. Gertrude Gutierrez, Justin Peruzzi, Ivan Bakker, Ruud J. R. W. Peters, Bianka Siewert, et al. "Evaluation of dextran(ethylene glycol) hydrogel films for giant unilamellar lipid vesicle production and their application for the encapsulation of polymersomes." Soft Matter 13, no. 33 (2017): 5580–88. http://dx.doi.org/10.1039/c7sm00551b.

Full text

APA, Harvard, Vancouver, ISO, and other styles

50

Holtz, John H., and Sanford A. Asher. "Polymerized colloidal crystal hydrogel films as intelligent chemical sensing materials." Nature 389, no. 6653 (October 1997): 829–32. http://dx.doi.org/10.1038/39834.

Full text

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Colloidal hydrogel'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles