00000caa a22000003i 4500 UP-1685594773862388537 Buklod 20210318135321.0 m | | ta 210318s2018 xx r |||| u|eng d (iLib)UPBAG-00039513728 STII-DOST BAG rda eng ARTICLE-2725 Atayde, Jr., Eduardo C. author. Temperature- and pH-dependent drug release of block copolymers of methacrylic acid and poly (ethylene glycol) methyl ether methacrylates by Eduardo C. Atayde Jr., Reynaldo Carlos K. Montalbo, and Susan D. Arco. 2018. pages 363-372 illustrations (some color) 26 cm text rdacontent unmediated rdamedia volume rdacarrier Includes bibliographical references (pages 371-372) The block copolymers, poly(methacrylic acid)-b-poly(di(ethylene glycol) methyl ether methacrylate) (Block-D) and poly(methacrylic acid)-b-poly(poly(ethylene glycol) methyl ether methacrylate) (Block-P) were synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization towards the development of stimuli-responsive carriers of poorly water-soluble drugs. The structures of the copolymers and the confirmation of successful block copolymerization were studied using proton nuclear magnetic resonance (1H-NMR) spectroscopy. Data from gel permeation chromatography (GPC) then showed polydispersity indices (PDI) close to 1.0, characteristic of RAFT polymerization. Stimuli-response studies revealed Block-D was responsive at pH 5.15 and 26°C while Block-P was responsive at pH 5.15 and 72°C. The corresponding micelles had particle sizes of 92.95-201.4 nm, as determined by dynamic light scattering (DLS), with critical micelle concentration (CMC) at about 10-1 mg/mL, per fluorescence studies. Using ibuprofen as the model drug, the drug loading content reached 11.76%, at 66.65% efficiency. In vitro release profiles then demonstrated 18% drug release within 5 h at stomach-like conditions, and 65% release within 5 h at small intestine-like conditions. Ultimately, cell viability assays of the blank and loaded micelles confirmed that neither is cytotoxic. These results show the immense potential and capability of the synthesized material as a drug delivery system for poorly water-insoluble drugs. Chemistry. Block copolymer. Drug delivery. Ph-responsive. Raft. Thermo-responsive. Montalbo, Reynaldo Carlos K. author. Arco, Susan D. author. The Philippine Journal of Science Vol. 147, no. 3, September 2018. Request full-text access via UPB University Library through https://forms.gle/KZjBv7aRtY6jiL5E9 (viewed 18 March 2021) FI UPBAG UPBAG-MAIN ARTICLE-2725 Analytics