title: 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.
authors.affiliation: Department of Chemical and Materials Engineering, Chang Gung University, Kwei-shan, Taoyuan 333, Taiwan.
authors.forename: Shingjiang Jessie
authors.initials: SJ
authors.lastname: Lue
authors.forename: Bo-Wei
authors.initials: BW
authors.lastname: Chen
authors.forename: Chao-Ming
authors.initials: CM
authors.lastname: Shih
authors.forename: Feng-Yi
authors.initials: FY
authors.lastname: Chou
authors.forename: Jui-Yang
authors.initials: JY
authors.lastname: Lai
authors.forename: Wen-Yen
authors.initials: WY
authors.lastname: Chiu
mesh_terms: D000178:Acrylamides / Q000737:chemistry*; D002626:Chemistry, Pharmaceutical / Q000379:methods*; D016503:Drug Delivery Systems; D015195:Drug Design; D005782:Gels; D020100:Hydrogels / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007840:Latex / Q000737:chemistry*; D015233:Models, Statistical; D053758:Nanoparticles / Q000737:chemistry; D036103:Nanotechnology / Q000379:methods*; D010316:Particle Size; D011108:Polymers / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013501:Surface-Active Agents; D013696:Temperature; D013997:Time Factors
chemical_list: D000178:Acrylamides; D005782:Gels; D020100:Hydrogels; D007840:Latex; C090629:N-isopropylacrylamide-acrylic acid copolymer; D011108:Polymers; D013501:Surface-Active Agents