Stimuli-Responsive Polymers in Nanotechnology: Deposition and Possible Effect on Drug Release

Abstract

Abstract. Stimuli-responsive polymers result in on-demand regulation of properties and functioning of various nanoscale systems. In particular, they allow stimuli-responsive control of flow rates through membranes and nanofluidic devices with submicron channel sizes. They also allow regulation of drug release from nanoparticles and nanofibers in response to temperature or pH variation in the surrounding medium. In the present work two relevant mathematical models are introduced to address precipitation-driven deposition of surface layers of stimuli-responsive polymers and describe a possible effect of swelling-shrinkage transition of such polymers on drug release.

Mechanoresponsive polymer nanoparticles, nanofibers and coatings as drug carriers and components of microfluidic devices

“…The release trends depicted in Fig. 9b and c are consistent with any of the two mechanisms proposed in the literature: either a further exposure of the existing nanopores, 76 or formation of new ones in the vicinity of PNIPAM nanogel islands, 72 since each of these mechanisms should dramatically occur at the temperature transition through LCST. The increase in the overall release in the temperature range from 40 C to 55 C in Fig.…”

“…In particular, staining was used to reveal the inhomogeneity of the individual PAA/PVA/PNI-PAM nanofibers resulting from the aggregation of PNIPAM in the form of ''raisins'', as it was suggested in the preceding theoretical work. 72 In the nanofibers, only PNIPAM contains nitrogen (in distinction from PAA and PVA), which is more likely to coordinate with Cu 2+ than the other atoms, e.g. such as O.…”

Basic concepts and recent advances in nanogels as carriers for medical applications

“…Also, by using the stimuli-responsive polymers capable of responding by a phase transition to diverse medically relevant stimuli changing, nanogels will be able to have an intelligent behavior (Börner et al, 2010 ; Cuggino et al, 2011 ; Jochum & Theato, 2013 ; Steinhilber et al, 2013 ; Giulbudagian et al, 2014 ; Molina et al, 2014 ; Tong et al, 2014 ). This property brought a considerable impact in the use of nanogels like biomedical delivery systems, comparative to the conventional ones (Whitcombe et al, 1997 ; Ganta et al, 2008 ; Maharjan et al, 2008 ; Yarin, 2008 ; Musyanovych & Landfester, 2014 ).…”

Stress-strain dependence for soy-protein nanofiber mats

“…Following our previous works, [17][18][19] consider a material with n potential defects per unit volume, which might be responsible for a local rupture. In the present context, these defects are associated with the interfiber bonds.…”

“…19 and is included here for completeness of discussion. The probability density function of a bond to be ruptured by an effective normal stress r 11 [related to stretching along the Ox 1 axis (cf.…”