Disease relevance of N-isopropylacrylamide

• Drug-incorporated ultra-low-sized nanogels (approximately 90 nm in diameter) composed of cross-linked random co-polymer of N-isopropylacrylamide (NIPAAM) and N-vinyl pyrrolidone(VP) were prepared, characterized and used as delivery vehicles to combat experimental leishmaniasis in hamster models [1].
• After 15 days' treatment with acrylamide and N-isopropylacrylamide, slight signs of peripheral neuropathy were produced with no changes in the activity of either enzyme [2].
• A copolymer of N-isopropylacrylamide (98 mole% in the feed) and acrylic acid poly(N-isopropylacrylamide-co-acrylic acid) [p(NiPAAm-co-AAc)], and the adhesion molecule, an Arg-Gly-Asp (RGD)-incorporated hydrogel, were used to entrap pheochromocytoma cells (PC12) [3].
• A copper-charged copolymer of N-isopropyl acrylamide (NIPAM) and vinyl imidazole (VI) is used to purify plasmid from an alkaline lysate of E. coli [4].

High impact information on N-isopropylacrylamide

• More specifically, we used differing combinations of N-isopropylacrylamide, which is presently used as an adaptive cell culture substrate, and the more hydrophobic, yet structurally similar, monomer N-tert-butylacrylamide [5].
• The kinetics of catalysis by the gel in the shrunken state is well described by the Michaelis-Menten formula, indicating that the absorption of the substrate by the hydrophobic environment created by the N-isopropylacrylamide polymer in the shrunken gel is responsible for enhancement of catalytic activity [6].
• Water-soluble block copolymers were prepared from the nonionic monomer N-isopropylacrylamide (NIPA) and the zwitterionic monomer 3-[N-(3-methacrylamidopropyl)-N,N-dimethyl]ammoniopropane sulfonate (SPP) by sequential free radical polymerization via the RAFT process [7].
• Five fluorescent monomers having a benzofurazan skeleton were synthesized, and the copolymers of N-isopropylacrylamide (NIPAM) and a small quantity of the fluorescent monomer were obtained to investigate their fluorescence properties [8].
• Photo-reversible Pb2+-complexation in a purely aqueous environment exhibiting a thermosensitive phase transition at a lower critical solution temperature was achieved using a synthetic copolymer composed of N-isopropyl acrylamide and spiropyran acrylate [9].

Biological context of N-isopropylacrylamide

• A short, single-stranded oligonucleotide sequence (namely (CTT)(7)), which is capable of recognizing a complementary sequence in the double-stranded target (plasmid) DNA, is linked to a thermoresponsive N-isopropylacrylamide oligomer to form a so-called affinity macroligand (AML) [10].
• Although the morphology of cells adhered to RGD-grafted NiPAM/NASI surfaces was comparable to cells adhered on tissue culture polystyrene (TCPS), long-term cell growth was limited on the NiPAM/NASI surfaces, even for RGD-grafted surfaces [11].
• The aim of this study was to characterize a pH-sensitive liposome formulation bearing a terminally alkylated N-isopropylacrylamide (NIPAM) copolymer with regard to its pH responsiveness, surface properties, and pharmacokinetics [12].
• In this study, we investigated different types of polyethyleneimine (PEI) and their block copolymers with N-isopropylacrylamide (NIPA) as temperature-sensitive polycationic non-viral vectors for transfection of HeLa cells in cell culture media [13].
• Hydrogels composed of N-isopropylacrylamide (NIPAAm) and acrylic acid (AAc) were prepared by redox polymerization with peptide cross-linkers to create an artificial extracellular matrix (ECM) amenable for testing hypotheses regarding cell proliferation and migration in three dimensions [14].

Anatomical context of N-isopropylacrylamide

• Egg yolk phosphatidylcholine liposomes modified with a copolymer of N-acryloylpyrrolidine and N-isopropylacrylamide having a lower critical solution temperature at ca. 40 degrees C were prepared and an effect of temperature on their interaction with CV1 cells was investigated [15].
• In the absence of BMP-2, cells cultured on NiPAM/NASI polymers (either grafted with RGD peptide or not) expressed significantly higher levels of ALP activity than the cells cultured on TCPS, indicating that the polymer surfaces induced some osteoblastic activity in C2C12 cells without the need for BMP-2 [11].
• 'On-off' regulation of drug permeation through membranes in response to external temperature change has already been achieved using thermosensitive copolymers of N-isopropyl acrylamide (IPAAm) with butyl methacrylate (BMA) [16].
• Thermoresponsive artificial extracellular matrix: N-isopropylacrylamide-graft-copolymerized gelatin [17].
• A copolymer of N-isopropylacrylamide (98 mol% in feed) and acrylic acid, poly(N-isopropylacrylamide-co-acrylic acid) (P(NIPAAm-co-AAc)), was prepared by free radical polymerization for development of a thermally reversible polymer to entrap islets of Langerhans for a refillable biohybrid artificial pancreas [18].

Associations of N-isopropylacrylamide with other chemical compounds

• Here, we describe the microbicide-oriented characterization of a DDS made with a dual pH sensitive and thermosensitive smart polymer gel composed of a random terpolymer of N-isopropyl acrylamide, butyl methacrylate, and acrylic acid [19].
• New thermo-responsive, pH-responsive, and biodegradable nanoparticles comprised of poly(D,L-lactide)-graft-poly(N-isopropyl acrylamide-co-methacrylic acid) (PLA-g-P(NIPAm-co-MAA)) were developed by grafting biodegradable poly(D,L-lactide) onto N-isopropyl acrylamide and methacrylic acid [20].
• We synthesized two thermally responsive polymers that were designed to exhibit a lower critical solution temperature (LCST) transition slightly above physiological temperature: (1) a genetically engineered elastin-like polypeptide (ELP) and (2) a copolymer of N-isopropylacrylamide (NIPAAm) and acrylamide (AAm) [21].
• Well-defined comb-shaped copolymer-Si(100) hybrids were prepared, via successive surface-initiated atom transfer radical polymerizations (ATRPs) of glycidyl methacrylate (GMA) and N-isopropylacrylamide (NIPAAm), for accelerated cell detachment at a lower temperature [22].
• pH and temperature-sensitive N-isopropylacrylamide ampholytic networks incorporating L-lysine [23].

Gene context of N-isopropylacrylamide

• METHODS: Random terpolymers of varying MW were synthesized with NIPAAm/BMA/AA of feed mol ratio 85/5/10 [24].
• To improve the properties of a reversible synthetic extracellular matrix based on a thermally reversible polymer, copolymers of N-isopropylacrylamide and acrylic acid were prepared in benzene with varying contents of acrylic acid (0 to 3%) and the thermal properties were evaluated [25].
• We conclude that NiPAM-based thermoreversible biomaterials, despite their limited ability to support cell growth, allowed an enhanced expression of the chosen osteogenic marker (ALP) by C2C12 cells in vitro [11].
• These bio-functionalized interfaces were prepared by electron beam-induced copolymerization of N-isopropylacrylamide (IPAAm) with its carboxyl-derivatized analog, 2-carboxyisopropylacrylamide (CIPAAm), and grafting onto tissue culture polystyrene dishes, followed by immobilization of RGDS and/or INS to CIPAAm carboxyls [26].
• All these analogues also produced a reduction in the two enzyme activities, except for enolase after N-isopropylacrylamide [2].

Analytical, diagnostic and therapeutic context of N-isopropylacrylamide

• Temperature-responsive liquid chromatography. 2. Effects of hydrophobic groups in N-isopropylacrylamide copolymer-modified silica [27].
• The pulse radiolysis technique has been employed to determine the initiation and propagation rates of different transient species involved in the polymerization of N-isopropylacrylamide (NIPA) in aqueous solutions [28].
• Detection by circular dichroism of conformational transitions in pH and thermosensitive copolymers based on N-isopropylacrylamide and N-methacryloyl-L-leucine [29].
• Networks of N-isopropylacrylamide (NIPAM) copolymers, coupled to spherical phospholipid bilayers, are suitable as a model for the study of the interaction between the cytoskeleton and cellular membranes, as well as for promising new drug delivery systems with triggerable drug release properties and improved stability [30].
• In vitro studies on a new method for islet microencapsulation using a thermoreversible gelation polymer, N-isopropylacrylamide-based copolymer [31].

References