International Journal of Pharmaceutical Investigation, 2011, 1, 2, 88-92.
DOI: 10.4103/2230-973X.82402
Published: June 2011
Type: Original Article
Authors:
Sung-Wook Choi
Division of Biotechnology, The Catholic University of Korea, Gyeonggi-do 420-743, South Korea
Hye Min Lee
Department of Chemical Engineering, Yonsei University, Seoul 120-749, South Korea
Tae-Joon Park
Department of Chemical Engineering, Yonsei University, Seoul 120-749, South Korea
Jung-Hyun Kim
Department of Chemical Engineering, Yonsei University, Seoul 120-749, South Korea
ABSTRACT
This paper describes the synthesis of thermosensitive surfactants by polymerizing N-isopropylacrylamide (NIPAAm) into the Pluronic F68 surfactant and their application for a controlled drug release. Poly(NIPAAm)-Pluronic surfactants with different lengths of the NIPAAm block were synthesized by activating two hydroxyl groups of poly(ethylene oxide) (PEO) at the end of Pluronic F68 using cerium ammonium nitrate (CAN, redox initiator), followed by adding the NIPAAm monomer into a reactor. The resultant poly(NIPAAm)-Pluronic surfactants were characterized by FT-IR and gel filtration chromatography (GPC). It was observed that their critical micellar concentrations increased with an increase in the length of the poly(NIPAAm) block. In addition, poly(d,l-lactide-co-glycolide) (PLGA) microparticles was prepared by an oil-inwater emulsion and solvent evaporation method using the poly(NIPAAm)-Pluronic surfactants in an aqueous continuous phase. At 37°C, nile red (model dye) was released from the PLGA microparticles in a more sustained manner when the length of poly(NIPAAm) was longer due to a thicker layer of shrunken poly(NIPAAm) at the surface of the microparticles.
Keywords: Controlled drug release, N-isopropylacrylamide (NIPAAm), Pluronic F68, Redox polymerization, Thermosensitive surfactant.