Phase transition of pNIPAM grafted on plasma-activated PEO monitored in-situ by quartz crystal microbalance

Heinz, Paul; Bretagnol, F.; Mannelli, Ilaria; Gillil, D; Rauscher, Hubert; Rossi, François

doi:10.1088/1742-6596/100/1/012033

Cited by 6 publications

(3 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The positive ion spectra recorded for the PNIPAM coating (Figure 1a) show a series of peaks for m/z values equal to 58, 72, and 114, which correspond to positive C 3 H 8 N + , C 3 H 6 NO + , and C 6 H 12 NO + ions characteristics for PNIPAM, 66 whereas for spectra measured for the PHEMA brush (Figure 1c), a series of oxygen-containing hydrocarbons such as C 2 H 5 O + , C 4 H 5 O + , and C 6 H 9 O 2 + ions, typical for PHEMA, 67 may be observed. In turn, for the representative P(NIPAM-co-HEMA) copolymer brush (Figure 1b), peaks indicating the presence of both polymers, i.e., PNIPAM and PHEMA, are visible, thus confirming the successful fabrication of the coatings.…”

Section: Composition Of the Coatingsmentioning

confidence: 99%

Thermoresponsive Smart Copolymer Coatings Based on P(NIPAM-co-HEMA) and P(OEGMA-co-HEMA) Brushes for Regenerative Medicine

Tymetska,

Shymborska,

Stetsyshyn

et al. 2023

ACS Biomater. Sci. Eng.

View full text Add to dashboard Cite

The fabrication of multifunctional, thermoresponsive platforms for regenerative medicine based on polymers that can be easily functionalized is one of the most important challenges in modern biomaterials science. In this study, we utilized atom transfer radical polymerization (ATRP) to produce two series of novel smart copolymer brush coatings. These coatings were based on copolymerizing 2-hydroxyethyl methacrylate (HEMA) with either oligo(ethylene glycol) methyl ether methacrylate (OEGMA) or N-isopropylacrylamide (NIPAM). The chemical compositions of the resulting brush coatings, namely, poly(oligo(ethylene glycol) methyl ether methacrylate-co-2-hydroxyethyl methacrylate) (P(OEGMA-co-HEMA)) and poly(N-isopropylacrylamide-co-2-hydroxyethyl methacrylate) (P(NIPAM-co-HEMA)), were predicted using reactive ratios of the monomers. These predictions were then verified using time-of-flight-secondary ion mass spectrometry (ToF-SIMS) and X-ray photoelectron spectroscopy (XPS). The thermoresponsiveness of the coatings was examined through water contact angle (CA) measurements at different temperatures, revealing a transition driven by lower critical solution temperature (LCST) or upper critical solution temperature (UCST) or a vanishing transition. The type of transition observed depended on the chemical composition of the coatings. Furthermore, it was demonstrated that the transition temperature of the coatings could be easily adjusted by modifying their composition. The topography of the coatings was characterized using atomic force microscopy (AFM). To assess the biocompatibility of the coatings, dermal fibroblast cultures were employed, and the results indicated that none of the coatings exhibited cytotoxicity. However, the shape and arrangement of the cells were significantly influenced by the chemical structure of the coating. Additionally, the viability of the cells was correlated with the wettability and roughness of the coatings, which determined the initial adhesion of the cells. Lastly, the temperature-induced changes in the properties of the fabricated copolymer coatings effectively controlled cell morphology, adhesion, and spontaneous detachment in a noninvasive, enzyme-free manner that was confirmed using optical microscopy.

show abstract

Section: Composition Of the Coatingsmentioning

confidence: 99%

Thermoresponsive Smart Copolymer Coatings Based on P(NIPAM-co-HEMA) and P(OEGMA-co-HEMA) Brushes for Regenerative Medicine

Tymetska,

Shymborska,

Stetsyshyn

et al. 2023

ACS Biomater. Sci. Eng.

View full text Add to dashboard Cite

show abstract

“…Conversely, E res of AuNR@pNIPAM 580 nanohybrids returned to the initial value upon cooling and did not exhibit hysteresis (Figure D, right). Hysteresis in pNIPAM phase transitions has previously been observed and may arise from dissimilar polymer network density or from interchain hydrogen bonds that form aggregates that persist even after cooling below the VPTT for the AuNR@pNIPAM 300 nanohybrids. ,,,− …”

Section: Results and Discussionmentioning

confidence: 96%

“…This observation agrees with our ensemble UV–vis measurements. Hysteresis in the VPT of pNIPAM results from pNIPAM aggregates formed by interchain hydrogen bonds that are not disrupted when cooled. ,− This likelihood of pNIPAM aggregate formation decreases with increasing polymer network chain length, which accounts for the limited hysteresis observed for AuNR@pNIPAM 580 nanohybrids …”

Section: Results and Discussionmentioning

confidence: 99%

Heterogeneity and Hysteresis in the Polymer Collapse of Single Core–Shell Stimuli-Responsive Plasmonic Nanohybrids

et al. 2021

View full text Add to dashboard Cite

Broad application of polymeric stimuli-responsive smart nanohybrids requires understanding the mechanisms governing active control. Ensemble techniques have identified inhomogeneous polymer collapse in microgels that potentially arise from heterogeneous interchain interactions and differences in core size. A single-particle examination would establish the influence of core size and internal polymer network heterogeneity on local interactions that contribute to the observed inhomogeneous polymer collapse dynamics of nanohybrids. Using single-particle dark-field spectroscopy, we investigated the complex polymer collapse profiles of core–shell plasmonic nanohybrids comprising thermoresponsive poly(N-isopropylacrylamide) (pNIPAM)-encapsulated gold nanorods (AuNRs). We report that the polymer collapse behavior was independent of the core size. For thinner polymer shells, we observed hysteresis in the collapse of AuNR@pNIPAMs, likely related to local pNIPAM aggregation due to interchain hydrogen bonding. For thicker polymer shells, we observed a broad polymer collapse distribution that we attributed to a two-step phase transition that arises from a polymer network density gradient. Our single-particle approach relates the internal heterogeneity of the polymer network of nanohybrids to the mechanisms underlying heterogeneous phase transitions that traditional, ensemble-averaged approaches are unable to discern.

show abstract

Covalent functionalization of silica nanoparticles with poly(N-isopropylacrylamide) employing thiol-ene chemistry and activator regenerated by electron transfer ATRP protocol

et al. 2013

View full text Add to dashboard Cite

Phase transition of pNIPAM grafted on plasma-activated PEO monitored in-situ by quartz crystal microbalance

Cited by 6 publications

References 7 publications

Thermoresponsive Smart Copolymer Coatings Based on P(NIPAM-co-HEMA) and P(OEGMA-co-HEMA) Brushes for Regenerative Medicine

Thermoresponsive Smart Copolymer Coatings Based on P(NIPAM-co-HEMA) and P(OEGMA-co-HEMA) Brushes for Regenerative Medicine

Heterogeneity and Hysteresis in the Polymer Collapse of Single Core–Shell Stimuli-Responsive Plasmonic Nanohybrids

Covalent functionalization of silica nanoparticles with poly(N-isopropylacrylamide) employing thiol-ene chemistry and activator regenerated by electron transfer ATRP protocol

Contact Info

Product

Resources

About