title: pH responsive poly amino-acid hydrogels formed via silk sericin templating.
abstract: Poly(amino acid) hydrogels have attracted a great deal of attention as biodegradable biomaterials that can limit products of synthetic polymer degradation. Here we report on a stimuli-responsive, porous, composite biomaterial based on the protein templating of the poly(amino acid) hydrogel from poly(aspartic acid) with the silk protein sericin. This low-cost, biocompatible and biodegradable hydrogel demonstrates a greatly increased porosity and improvement in volumetric swelling over networks formed from pure poly(aspartic acid). The swelling capacity measured over a range of pH values surrounding physiological pH 7.0 demonstrates a linear profile, in which hydrogel volume and mass increase to a maximum, with an increase as a function of higher sericin content. In comparison to pure poly(aspartic acid), this demonstrates a nearly 3-fold increase in retention volume at basic pH. The increase in swelling is also demonstrated by the increase in porosity and internal micro-architecture of the hydrogel networks. The biomaterial is then shown to perform well as a scaffold for cells with high mechanical strength and integrity. This protein- and homo poly(amino acid)-based super-swelling hydrogel has applications in drug delivery and tissue engineering as an economical and environmentally friendly biomaterial, in addition to ensuring the species incorporated maintain their biocompatibility during processing.
authors: Department of Chemical and Life Science Engineering, Virginia Commonwealth University, Richmond VA 23284, USA.
authors: Nicholas E
authors: NE
authors: Kurland
authors: Department of Chemical and Life Science Engineering, Virginia Commonwealth University, Richmond VA 23284, USA.
authors: Robert B
authors: RB
authors: Ragland
authors: Department of Chemical and Life Science Engineering, Virginia Commonwealth University, Richmond VA 23284, USA.
authors: Aolin
authors: A
authors: Zhang
authors: Department of Chemical and Life Science Engineering, Virginia Commonwealth University, Richmond VA 23284, USA.
authors: Mahmoud E
authors: ME
authors: Moustafa
authors: Department of Biotechnology, Indian Institute of Technology, Kharagpur 721302, India.
authors: Subhas C
authors: SC
authors: Kundu
authors: Department of Chemical and Life Science Engineering, Virginia Commonwealth University, Richmond VA 23284, USA. Electronic address: vyadavalli@vcu.edu.
authors: Vamsi K
authors: VK
authors: Yadavalli
mesh_terms: D000327:Adsorption; D000596:Amino Acids / Q000737:chemistry*; D001672:Biocompatible Materials / Q000737:chemistry; D018929:Cell Culture Techniques; D002460:Cell Line; D020100:Hydrogels / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D018625:Microscopy, Atomic Force; D011108:Polymers / Q000737:chemistry*; D016062:Porosity; D047030:Sericins / Q000737:chemistry*; D047011:Silk / Q000737:chemistry*
chemical_list: D000596:Amino Acids; D001672:Biocompatible Materials; D020100:Hydrogels; D011108:Polymers; D047030:Sericins; D047011:Silk
keywords: Hydrogel; Polyaspartic Acid; Sericin; Silk; pH responsive