Micron- and Nano-sized Poly(N-isopropylacrylamide-co-acrylic acid) Latex Syntheses and Their Applications for Controlled Drug Release

Abstract

Thermo-sensitive poly(N-isopropylacrylamide-co-acrylic acid) (P(NIPAAm-co-AAc)) latex particles were prepared with and without sodium dodecyl sulfate (SDS) surfactant via an emulsion polymerization method. The P(NIPAAm-co-AAc) latex particle sizes were approximately 1.1 microm without SDS addition and the particle sizes were in the nanometer range (59 nm) with SDS at its critical micelle concentration (CMC) of 8 mM. We propose a scheme to demonstrate how the SDS concentration affects the synthesized latex particle size. The lower critical solution temperature (LCST) was hardly influenced by the SDS level but increased with the AAc concentration. The PNIPAAm-co-AAc latex particles were employed as thermo-sensitive drug carriers and 4-acetamidophenol was loaded to study the drug release rates from the nano-gels. The effective drug diffusion coefficients within the nano-gels varied as a function of particle size, AAc content, and temperature. The smaller or AAc-rich hydrogel particles provided sustainable drug release property and have potential use in biomedical applications.

Poly(N-isopropylacrylamide) and Copolymers: A Review on Recent Progresses in Biomedical Applications

“…Microgels and nanogels from NIPAAm and acrylic monomers have also been studied [100,101]. Zhan et al [102] recently reported the synthesis of poly( N -isopropylacrylamide- co -acrylic acid) nanogels—named PNA-BAC NGs—for anticancer drug delivery.…”

Novel quaternized polyvinyl alcohol/quaternized chitosan nano-composite as an effective hydroxide-conducting electrolyte

“…The micro-structure of the Q-PVA and Q-PVA/Q-chitosan membranes was observed using a field emission scanning electron microscope (FESEM, model JSM-7500F, Hitachi High-Technologies Corp., Tokyo, Japan) after being freeze-fractured in liquid nitrogen and sputtered with Au. The particle size distribution of the ϳ Q-chitosan suspension was measured using laser light scattering analyzer (Zetasizer, 2000 HAS, Malvern, Worcestershire, UK) [32].…”

Surfactant-Assisted Perovskite Nanofillers Incorporated in Quaternized Poly (Vinyl Alcohol) Composite Membrane as an Effective Hydroxide-Conducting Electrolyte

“…Thermal stability was determined via thermo-gravimetric analysis (TGA) [54]. Particle zeta potentials were evaluated using a dynamic light scattering analyser (Zetasizer, 2000 HAS, Malvern, Worcestershire, UK) [77,78]. Particle suspension conductivities were measured using a conductivity meter while membrane conductivity was obtained from alternate-current impedance spectra [10].…”