02658nas a2200169   4500008004100000245013400041210006900175260000800244300001200252490000600264520200000270100002402270700002402294700002302318700002402341856012302365       2017                        eng d00aTailoring the properties of mPEG-PLLA nanoparticles for better encapsulation and tuned release of the hydrophilic anticancer drug0 aTailoring the properties of mPEGPLLA nanoparticles for better en  cJUN  a416-4270 v73 aGemcitabine is used as a first-line drug for treating many solid tumours. However, it suffers from a major drawback of strong side effects and short plasma half-life because of degradation by enzyme when administered intravenously. Polyesters and copolyesters are the most widely used and preferred class of biodegradable polymer. In the present work, efforts have been made to prepare poly(ethylene glycol) monomethoxy ether-poly(l-lactide) (mPEG-PLLA), a biodegradable amphiphilic copolymer with a view to improve the entrapment and tuned release of hydrophilic drug gemcitabine. The different mPEG-PLLA copolymers were synthesized with the varying ratios of mPEG and characterized by different techniques namely FTIR and ¹H NMR spectroscopy, solution viscosity, differential scanning calorimetry (DSC) and gel permeation chromatography (GPC). Gemcitabine-loaded nanoparticles were prepared using mPEG-PLLA copolymers by two methods i.e. nanoprecipitation and double emulsion solvent evaporation. The nanoprecipitation method showed very less entrapment and polymer solubility in the acetone-water mixture leading to uncontrolled polymer precipitation. The difficulties encountered in the nanoprecipitation method were overcome with the help of the double emulsion (w/o/w) solvent evaporation technique. It has been observed from the results that biodegradable copolymer nanoparticles protect the drug from degradation and also help in controlling the release of encapsulated drug. The properties of nanoparticles can be tailored by varying the composition of mPEG in order to get improved entrapment efficiency and desired drug release. The nanoparticles were assessed for their in vitro cytotoxicity (MTT and FACS) and cellular uptake (fluorescence microscopy) study which showed very promising results. Nanoparticles were also studied for their in vivo release after intravenous administration to Wistar albino rats, which successfully showed controlled drug release for more than 14 days.1 aSurwase, Sachin, S.1 aMunot, Neha, Manish1 aIdage, Bhaskar, B.1 aIdage, Susheela, B.  uhttps://library.ncl.res.in/content/tailoring-properties-mpeg-plla-nanoparticles-better-encapsulation-and-tuned-release