Synthesis and Characterization of a Novel Starch-Based pH-Sensitive Hydrogel

Stimuli-responsive hydrogels are extensively investigated to implement new biomedical and pharmaceutical approaches. In this work, novel pH-sensitive hydrogel, with potassium persulfate as the initiator, acrylic acid and butyl methacrylate as graft monomer, were synthesized by microwave irradiation. FT-IR measurements testified the hydrogels formed structure. The SEM micrographs revealed that the porous structures of hydrogels changed with the increasing AA content. The experimental results demonstrated that the gels do not swell greatly at low pH media whereas they swelled sufficiently at high pH media, exhibiting smart pH sensitivity.

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ATRP Synthesis and Characterization of μ,αω-allyl-terminated Macromonomers as Precursors for End-linked Gels and Hydrogels

MRS Proceedings ◽

10.1557/proc-774-o1.8 ◽

2003 ◽

Vol 774 ◽

Author(s):

Lucy Vojtova ◽

Nicholas J. Turro ◽

Jeffrey T. Koberstein

Keyword(s):

Molecular Weight ◽

Monomer Concentration ◽

Monomer Conversion ◽

Catalyst System ◽

Linear Increase ◽

Butyl Methacrylate ◽

First Order Kinetics ◽

Significant Difference ◽

Ft Ir

AbstractSynthesis of α,ω-allyl-terminated telechelic macromonomers based on poly(tert-butyl methacrylate) (poly(t-BMA)) and poly(methacrylic acid) (poly(MAA)) was studied with the aim of preparing end-linked gels and hydrogels. Low molecular weight α-allyl-terminated poly(t-BMA) macromonomers with narrow polydispersities (Mw/Mn = 1.16) were synthesized via controlled atom transfer radical polymerization (ATRP) using a Cu(I)Br/N,N,N',N',N',N'-hexamethyltriethylenetetraamine catalyst system in conjunction with an allyl-2-bromoisobutyrate as the functional initiator. The polymerizations exhibited a linear increase of molecular weight in direct proportion to the monomer conversion and first-order kinetics with respect to monomer concentration. No significant difference was found between using polar or non-polar solvents (tetrahydrofuran or benzene, respectively). Optimization of reaction conditions to obtain the highest degree of active terminal bromine is discussed. Quenching the ATRP reaction with allyltributyltin yielded α,ω-allyl-terminated poly(t-BMA) macromonomers by replacing the terminal bromine with ω-allyl functional group. Poly(MAA) macromonomers were prepared by deprotection of the tert-butyl group from α,ω-allyl-terminated poly(t-BMA) macromonomers using concentrated trifluoroacetic acid at room temperature. Successful synthetic steps were confirmed by 1H NMR, FT-IR and MALDI-TOF MS analyses. The α,ω-allyl-terminated macromonomers were proven to be candidates for further polymerization by forming end-linked, non-soluble gels.

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Preparation and characterization of pH-sensitive hydrogel for drug delivery system

RSC Advances ◽

10.1039/c2ra20989f ◽

2012 ◽

Vol 2 (20) ◽

pp. 7772 ◽

Cited By ~ 28

Author(s):

Ke Wang ◽

Qiang Fu ◽

Xi Chen ◽

Yang Gao ◽

Kai Dong

Keyword(s):

Drug Delivery ◽

Drug Delivery System ◽

Delivery System ◽

Ph Sensitive ◽

Ph Sensitive Hydrogel

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Preparation and characterization of N-(2-carboxybenzyl)chitosan as a potential pH-sensitive hydrogel for drug delivery

Carbohydrate Research ◽

10.1016/j.carres.2006.11.002 ◽

2007 ◽

Vol 342 (1) ◽

pp. 87-95 ◽

Cited By ~ 79

Author(s):

Youwen Lin ◽

Qing Chen ◽

Hongbing Luo

Keyword(s):

Drug Delivery ◽

Ph Sensitive ◽

Ph Sensitive Hydrogel

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Polyacryloyl hydrazide based injectable & stimuli responsive hydrogels with tunable properties

Journal of Materials Chemistry B ◽

10.1039/c4tb01257g ◽

2014 ◽

Vol 2 (42) ◽

pp. 7429-7439 ◽

Cited By ~ 4

Author(s):

Anuj Kumar ◽

Sabindra K. Samal ◽

Rupesh Dash ◽

Umaprasana Ojha

Keyword(s):

Polyethylene Glycol ◽

Acrylic Acid ◽

Diethyl Malonate ◽

Synthesis And Characterization ◽

Cross Linking ◽

Stimuli Responsive ◽

Polyethylene Glycol Diacrylate ◽

Glycol Diacrylate ◽

Responsive Hydrogels

The synthesis and characterization of a series of injectable and stimuli responsive hydrogels based on polyacryloyl hydrazide have been accomplished using dimethyl 2,2′-thiodiacetate, acrylic acid, diethyl malonate and polyethylene glycol diacrylate as cross-linkers through a chemical or dual cross-linking pathway.

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