title: Reaction of poly(acrylamide-co-vinylamine) with tresyl-PEG in the presence of PC12 cells.
abstract: Tresylation of an amine containing polymer film in the presence of PC12 cells did not result in a significant loss of cell viability, at least as assessed by trypan blue exclusion or MTT assay. PC12 cells were cultured atop reactive poly(acrylamide-co-vinyl amine) films or tissue culture polystyrene and exposed for 2 h to tresylated polyethylene glycol (TPEG) or unreactive hydrolyzed TPEG in 0.1M TES (N-tris hydroxymethyl-2-aminoethane sulfonic acid). The loss in trypan blue viability was limited ( approximately 80% retained), provided the TPEG concentration was 10 micromol/g or less. Similarly when microencapsulated PC12 cells (in a non-reactive polyacrylate hydrogel) were exposed to TPEG (10 micromol/g in 0.1M TES) the loss of MTT activity was small. The loss of vaibility was attributed to the toxicity of the tresyl leaving group and not the reaction itself. Thus, it may be possible to surface modify cell containing microcapsules, at least under limited conditions, in order to improve their biocompatibility without compromising the viability of the enclosed cells. This should lead to the development of new (reactive) polymers for microencapsulation since biocompatibility need not be a design consideration in the first instance.
authors.affiliation: Department of Chemical Engineering and Applied Chemistry, Institute for Biomaterials and Biomedical Engineering, University of Toronto, 4 Taddle Creek Road, Room 407D, Toronto, Ont., Canada M5S 3G9.
authors.forename: Yoji
authors.initials: Y
authors.lastname: Yamamoto
authors.forename: Michael V
authors.initials: MV
authors.lastname: Sefton
mesh_terms: D000588:Amines / Q000737:chemistry*; D000818:Animals; D001672:Biocompatible Materials / Q000494:pharmacology; D002470:Cell Survival; D004396:Coloring Agents / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004339:Drug Compounding; D006868:Hydrolysis; D016716:PC12 Cells; D011092:Polyethylene Glycols / Q000737:chemistry* / Q000494:pharmacology*; D011108:Polymers / Q000737:chemistry; D051381:Rats; D013778:Tetrazolium Salts / Q000494:pharmacology; D013844:Thiazoles / Q000494:pharmacology; D014343:Trypan Blue / Q000494:pharmacology
chemical_list: D000588:Amines; D001672:Biocompatible Materials; D004396:Coloring Agents; D011108:Polymers; D013778:Tetrazolium Salts; D013844:Thiazoles; D011092:Polyethylene Glycols; C022616:thiazolyl blue; D014343:Trypan Blue