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Thin film depositions of rf plasma polymerized N-isopropylacrylamide (ppNIPAM) show a phase transition temperature below which the polymer surface is hydrophilic, and protein nonadsorptive, and above which the polymer surface is hydrophobic, and protein-retentive. Results presented here demonstrate that this thermoresponsive plasma polymer can be coated on the surface of a MALDI probe and subsequently used for on-probe biomolecule cleanup. Specifically, a contaminated biomolecule can be applied to the ppNIPAM coated MALDI probe surface at a temperature above the phase transition temperature, washed using solvent also held above the phase transition temperature, and then analyzed by reducing the probe temperature to room temperature before adding the MALDI matrix. With the use of this approach, it is demonstrated that cytochrome c contaminated with 0.3% SDS, which yields only a very weak MALDI ion signal as directly deposited, can be purified on-probe using the thermoresponsive plasma polymer to improve significantly the ion signal. It is further shown that the decontamination of whole cell protein extracts from cyanobacteria is augmented through the use of the ppNIPAM coated MALDI probe.

The carboxyl-terminated trithiocarbonates were subjected to reversible addition-fragmentation chain transfer (RAFT) polymerization to obtain a series of triblock copolymers of poly (steryl methacrylate)-b-poly (N-isopropylacrylamide)-b-poly-stearyl methacrylate)( PSMA-b-PNIPAAm-b-PSMA) having different molecular weights. The polymers were found to be thermoresponsive and pH-responsive.

The temperature dependence of collapse and swelling of poly(N-isopropylacrylamide) (PNIPAM) brushes grafted on SiO(sub 2) surface in water with a quartz crystal microbalance. The results revealed that there exists a hysteresis in the swelling of the collapsed chains, which is attributed to the intrachain and interchain interactions formed in the collapsed state at higher temperatures and the nonuniformity of the brushes.

Several high-frequency dielectric relaxation techniques are employed to analyze the contrary hydration behavior of N-isopropylacrylamide (NIAPm) in homogeneous aqueous solution with its polymer poly(NIAPm) at its critical solution temperature. The analysis reveals the temperature dependence of the hydration behavior of the monomer describing and explaining the exchange processes of water molecules hydrated to the solutes and rotational relaxations of the solutes.

The article explains the synthesis, structure and properties of the various multicomponent core/shell microgels that are shown to consist of various decoupled poly(N-isopropylmethacrylamide) compound.

The grafted polymer from silicon nanowire arrays via surface-initiated atom transfer radical polymerization was used to construct nanoscale topography on a thermally responsive poly(N-isopropylacrylamide) (PNIPAAm) surface. The results provide insight into the applications of PNIPAAm in the fields of biomaterials and biomedicine under human physiological temperature and as a new strategy for fabricating other blood-compatible materials.

A thermoresponsive polymer, poly(N-isopropylacrylamide) (PNIPAM) was used to test the direct binding mechanism for urea-based denaturation of proteins. The results showed no evidence for the direct binding of any of the tested methylated ureas to the polymer amide moieties of FTIR and are inconsistent with a direct hydrogen-bonding mechanism for the urea-induced denaturation of proteins.

A new form factor model is used for analyzing small-angle neutron scattering data from a thermosensitive copolymer microgel consisting of N-isopropylacrylamide (PNIPAM) and N-isopropylmethacrylamide (PNIPMAM regions). The results have shown that a one-pot synthesis has led to a highly sophisticated material with phase separated domains on a microscopic length scale.

Ultraviolet-visible spectroscopy and several other techniques are employed to study the thermoresponsive behavior of the poly-(N-isopropylacrylamide) microgel particles embedded in a hydrogel matrix. The incorporation of the microgels is shown to lead to the temperature-sensitive optical properties of the composite materials.

The dynamic behavior of the phase separation of aqueous solutions is analyzed by a laser T-jump method. The studies have shown that the values of time constants increased linearly with increasing square of hydrodynamic radius.

A study is done on acrylamide heating and its elimination. The results found that table salt has substantial catalytic effects on the polymerization of acrylamide.

The behavior of a lower critical solution temperature (LCST) copolymer bearing a covalently attached solvatochromic dye is reported. Results demonstrated the possibility of changing the color of this copolymer through pH, type of solvent, temperature, and host-guest interaction with cyclodextrin.