Encapsulation of Biologicals within Silicate, Siloxane, and Hybrid Sol−Gel Polymers:  An Efficient and Generic Approach

Fine crystalline powders of KCuFC were immobilized with alginate gel polymers by sol-gel methods. The uptake properties of KCuFC-microcapsules (KCuFC-MC) were examined by batch and column methods. The size of KCuFC-MC particle was estimated to be about 1 mm in diameter, and KCuFC powders were uniformly dispersed in KCuFC-MC particles. The uptake rate of Pd2+ for KCuFC-MC was attained within 3 d, and the uptake of Pd2+ was found to be independent of the temperature and coexisting HNO3 concentration. As for the breakthrough properties of Pd2+ through a column packed with KCuFC-MC, a breakpoint of 5% breakthrough was enhanced with lowering of flow rate and independent of coexisting HNO3 concentration. The Pd2+ ions were selectively adsorbed in the KCuFC crystal phase, while other metal ions such as Ru(NO)3+ and ZrO2+ were absorbed in the alginate phase. High uptake percentage of 98.6% was obtained by using the dissolved solutions of spent fuel from FBR-JOYO (119 GWd/t, JAEA). The alginate film enclosing KZnFC was further prepared by using the support of cellulose filter paper, where the Pd2+ ions were selectively adsorbed on the KZnFC-MC film. The alginate film enclosing insoluble ferrocyanides are predicted for the selective separation of Pd2+ as an ion-exchange filter. Thus, the microcapsules enclosing insoluble ferrocyanides are effective for the selective separation of Pd2+ from high-level liquid waste (HLLW).

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IN SITU GEL POLYMERS: A REVIEW

International Journal of Applied Pharmaceutics ◽

10.22159/ijap.2021v13i1.39504 ◽

2021 ◽

pp. 86-90

Author(s):

MOUNIKA KONATHAM ◽

MOUNIKA TEJASWI GORLE ◽

NAVEEN PATHAKALA ◽

VASUDHA BAKSHI ◽

YASO DEEPIKA MAMIDISETTI ◽

...

Keyword(s):

Drug Administration ◽

Colloidal Suspension ◽

Sol Gel ◽

Patient Comfort ◽

In Situ Gel ◽

Gel Polymers ◽

Characteristic Features ◽

In Situ Gelling ◽

Gel Transition

In situ gels have become one of the most prominent and accessible systems. These systems have several advantages like simple manufacturing, easy to use, improved adherence, and patient comfort by minimizing drug administration frequency by its unique characteristic features of sol to gel transition. In the 'sol-gel' method, the precursor goes through hydrolysis and polymerization or condensation to produce a colloidal suspension or solution. As they can administer in solution form, these in situ gelling systems undergo gelation at the achievement site. Some researchers recently developed in situ gelling systems of liposomes, microspheres, nanoemulsions, nanospheres, etc. This review mainly focused on the introduction, advantages, disadvantages, types of polymers, and suitable characteristics for preparing in situ gels.

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TEM visualization of surface replicated acid and base catalyzed sol-gel glasses

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010014381x ◽

1986 ◽

Vol 44 ◽

pp. 448-449

Author(s):

George C. Ruben ◽

Merrill W. Shafer

Keyword(s):

Elevated Temperatures ◽

Sol Gel ◽

Basic Medium ◽

Glass Transition Point ◽

Structural Space ◽

Acid And Base ◽

Organometallic Precursors ◽

New Processing ◽

Gel Glasses ◽

Physical Phenomena

Traditionally ceramics have been shaped from powders and densified at temperatures close to their liquid point. New processing methods using various types of sols, gels, and organometallic precursors at low temperature which enable densificatlon at elevated temperatures well below their liquidus, hold the promise of producing ceramics and glasses of controlled and reproducible properties that are highly reliable for electronic, structural, space or medical applications. Ultrastructure processing of silicon alkoxides in acid medium and mixtures of Ludox HS-40 (120Å spheres from DuPont) and Kasil (38% K2O &62% SiO2) in basic medium have been aimed at producing materials with a range of well defined pore sizes (∼20-400Å) to study physical phenomena and materials behavior in well characterized confined geometries. We have studied Pt/C surface replicas of some of these porous sol-gels prepared at temperatures below their glass transition point.

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