TY  - GEN
T1  - Temperature- and pH-dependent drug release of block copolymers of methacrylic acid and poly (ethylene glycol) methyl ether methacrylates
A1  - Atayde, Jr., Eduardo C.
A1  - Montalbo, Reynaldo Carlos K.
A1  - Arco, Susan D.
LA  - English
YR  - 2018
UL  - https://tuklas.up.edu.ph/Record/UP-1685594773862388537
AB  - 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.
CN  - ARTICLE-2725
KW  - Chemistry.
KW  - Block copolymer.
KW  - Drug delivery.
KW  - Ph-responsive.
KW  - Raft.
KW  - Thermo-responsive.
ER  -