title: Nanogel scavengers for drugs: local anesthetic uptake by thermoresponsive nanogels.
abstract: The use of functional nanogels based on poly(N-isopropylacrylamide) for effectively scavenging compounds (here, the model drug bupivacaine) is demonstrated using an in vitro cell-based assay. Nanogels containing higher loadings of acidic functional groups or more core-localized functional group distributions bound more bupivacaine, while nanogel size had no significant effect on drug binding. Increasing the dose of nanogel applied also facilitated more bupivacaine binding for all nanogel compositions tested. Binding was driven predominantly by acid-base interactions between the nanogels (anionic) and bupivacaine (cationic) at physiological pH, although both non-specific absorption and hydrophobic partitioning also contributed to drug scavenging. Nanogels exhibited minimal cytotoxicity to multiple cell types and were well tolerated in vivo via peritoneal injections, although larger nanogels caused limited splenic toxicity at higher concentrations. The cell-based assay described herein is found to facilitate more robust drug uptake measurements for nanogels than conventional centrifugation-based assays, in which nanogels can be compressed (and thus drug released) during the measurement.
authors.affiliation: Department of Chemical Engineering, McMaster University, 1280 Main St. W, Hamilton, Ontario, Canada L8S 4L7.
authors.forename: Todd
authors.initials: T
authors.lastname: Hoare
authors.forename: Daryl
authors.initials: D
authors.lastname: Sivakumaran
authors.forename: Cristina F
authors.initials: CF
authors.lastname: Stefanescu
authors.forename: Michael W
authors.initials: MW
authors.lastname: Lawlor
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Kohane
mesh_terms: D000779:Anesthetics, Local / Q000494:pharmacology*; D000818:Animals; D001672:Biocompatible Materials / Q000494:pharmacology; D002045:Bupivacaine / Q000494:pharmacology; D016923:Cell Death / Q000187:drug effects; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D004586:Electrophoresis; D006801:Humans; D008422:Materials Testing; D051379:Mice; D018485:Muscle Fibers, Skeletal / Q000166:cytology / Q000187:drug effects; D000080385:Nanogels; D010316:Particle Size; D011092:Polyethylene Glycols / Q000737:chemistry*; D011094:Polyethyleneimine / Q000737:chemistry*; D013696:Temperature
chemical_list: D000779:Anesthetics, Local; D001672:Biocompatible Materials; D000080385:Nanogels; C413692:polyethylene glycol polyethyleneimine nanogel; D011092:Polyethylene Glycols; D011094:Polyethyleneimine; D002045:Bupivacaine