Fabrication of PVCL-co-PMMA nanofibers with tunable volume phase transition temperatures and maintainable shape for anti-cancer drug release

Abstract

This work is to fabricate thermo responsive nanofibers of which the thermo response temperatures could be easily tuned, and of which the fibrous shapes could be maintained after heating-cooling cycles in aqueous solution. The nanofibers were further fabricated into a nonwoven mat with size-variable pores for temperature controlled release of a model drug, Erlotinib. The thermo responsive nanofibers were electrospun from the copolymers of PMMA-co-PVCL (synthesized from MMA and PVCL, and had different LCSTs) by changing the solvents and the ratio of initiator/monomer. FT-IR and 1 H NMR were used for molecular structural characterization; UV-vis spectra were used for LCST measurement; SEM and metalloscope were used to determine the optimal electrospinning parameters and to observe the shape maintaining abilities of the nanofibers after the heating-cooling recycles. Then, anti-cancer drug, Erlotinib, was incorporated into PMMA/PVCL nanofibers (represent as 'model I'), or put in a drug reservoir and covered with the PMMA/PVCL electrospinning mat (presented as 'model II'). UV-vis spectra were used to study the drug release behavior of each model. Results indicate that in model I, drug release was "switch on" below LCST, and "switch off" above LCST; in model II, drug release was faster above LCST than below LCST.

Guar-Based Injectable Thermoresponsive Hydrogel as a Scaffold for Bone Cell Growth and Controlled Drug Delivery

“… 48 Figure S1b ( Supporting Information ) shows two peaks at 1627 and 1483 cm –1 that correspond to carbonyl (C=O) bond stretching and amide (C–N) stretching present in PNVCL, respectively. 49 In the HPG- g -PNVCL spectrum (Figure S1c, Supporting Information ), the increased intensity of O–H bond stretching at 3617 cm –1 was observed and it proves the grafting of PNVCL on HPG. Furthermore, peaks arising due to C=O stretching vibration at 1627 cm –1 and C–N bending vibration at 1474 cm –1 illustrate the successful grafting of PNVCL on HPG.…”

Synthesis, characterization and electrospinning of poly(vinyl caprolactam-co-hydroxymethyl acrylamide) to create stimuli-responsive nanofibers

“…The nanofiber mat exhibits higher dye release rate when the nanogel shrinks above LCST. This is an interesting result since most of the PVCL hydrogels known today are negative temperature-responsive (less release at temperature above the LCST) [6,26]. Intriguingly, Kim and co-workers [32] also used NMA as co-monomer to create NIPAAm based hydrogel nanofibers and they also observed a positive temperature-responsive dextran release.…”

“…Interestingly, there are few works in the literature related to the electrospinning of PVCL homopolymers and copolymers [26][27][28][29][30]. Webster and co-workers [30] electrospun PVCL homopolymer for the first time.…”

“…Paaver et al [28] studied the spinnability of the synthetic graft copolymer "Soluplus" (poly(vinyl caprolactam-vinyl acetate-ethylene glycol) graft copolymer) and the ability of the nanofibers to act as drug delivery systems. Yu et al [26] synthesized and electrospun poly(vinyl caprolactamco-methyl methacrylate) (P(VCL-co-MMA)) copolymers and studied the wettability, swelling capacity and drug release behavior of the created physical hydrogel nanofiber mats. In addition, Pich et al [29] electrospun poly(caprolactone) (PCL) together with PVCL nanogels to obtain composite nanofibers in a single electrospinning process.…”

Thermoresponsive Nanogels Based on Different Polymeric Moieties for Biomedical Applications

“…Polymer molecular weight can affect LCST. Because of its biocompatibility and low cytotoxicity, PVCL is considered an ideal thermoresponsive polymer for biomedical applications [ 97 , 98 , 99 ], particularly when compared to PNIPAM [ 100 , 101 , 102 ]. PVCL conjugation with hydrophilic units such as PEG or derivatives of PEG enables the synthesis of temperature-responsive block copolymers.…”