College of Bioengineering, Chongqing University, Chongqing, 400030, China.
J Biomed Nanotechnol. 2009 Jun;5(3):310-3. doi: 10.1166/jbn.2009.1036.
Novel thermosensitive nano-micelles, based on Poly(D,L-lactide-co-glycolide)-b-poly(ethylene glycol)-b-poly(D,L-lactide-co-glycolide) (PLGA-PEG-PLGA), as carriers for drug delivery were researched. The critical micelle concentration of the copolymer in aqueous solution was determined to be 2.34 microgram/ml by fluorescence spectroscopy using pyrene as a fluorescence probe. The lower critical solution temperature (LCST) of the copolymer was measured in distilled water by optical transmittance, and the LCST was varied from 35 to 55 degrees C depending on polymer concentration. Acetaminophen as a model drug was loaded in nano-micelles by solvent evaporation method. In vitro acetaminophen release from micelles showed a sustained modality compared with the free drug as a control, and an obviously high release rate when temperature was increased above LCST. The studies showed that nano-micelles made from PLGA-PEG-PLGA could be ideal candidate carriers for tumor-special drug delivery.
研究了基于聚（D，L-乳酸-co-乙二醇）-b-聚乙二醇-b-聚（D，L-乳酸-co-乙二醇）（PLGA-PEG-PLGA）的新型温敏纳米胶束作为药物传递载体。荧光探针芘荧光光谱法测定该共聚物在水溶液中的临界胶束浓度为 2.34μg/ml。用光透射法在去离子水中测定共聚物的低临界溶液温度（LCST），并根据聚合物浓度从 35 至 55°C 变化。采用溶剂蒸发法将扑热息痛作为模型药物载入纳米胶束中。与对照的游离药物相比，胶束中扑热息痛的体外释放呈现出持续的模式，当温度升高到 LCST 以上时，释放速度明显加快。研究表明，PLGA-PEG-PLGA 纳米胶束可以作为肿瘤特异性药物传递的理想载体。
