Photodynamic Therapy Functionalized Polymeric Nanoparticles For Cancer Therapy

In recent years,photodynamic therapy(PDT)has become a new treatment option for cancer.Unlike surgical resection,chemotherapy,radiotherapy,exactly targeted treatment is a significant advantage of PDT.Additionally,the same site can be treated by PDT if needed and it is also non-invasive.Nevertheless,because of the hydrophobicity of most PSs,it is phototoxicity to skin,and has unsatisfactory biodistribution.Docetaxel(DTX)which is the semi-synthetic taxane analog,has been broadly used to treat breast cancer,cervical cancer,non-small cell lung cancer etc.Due to its extremely low water solubility,Tween 80 isuse to solve DTX in clinicalpractice.However,Tween 80 could result in various side effects such as neurotoxicity and hypersensitivity reactions.In this work,the biodegradable polymeric nanoparticles(NPs),are used as drug delivery systems and may overcome the above disadvantages.We developed a system of NPs of a four-armed star-shaped porphyri-cored poly(lactide)-b-D-?-tocopherylpolyethylene glycol 1000 succinate amphiphilic copolymer(TAPP-PLA-b-TPGS)for combining chemotherapy with PDT to treat cancer.An arm-first approach was used to synthesized the star-shaped copolymer.And 1H NMR was used to characterized the structure of copolymer,and gel permeation chromatography(GPC)were used to estimate the molecular mass.NPs were prepared via a nanoprecipitation method by means of an acetone/water system.The resulting NPs were characterized through determination of their size and size distribution data as well as differential scanning calorimetry(DSC)assay.In drug release assays,the DTX-loaded NPs showed excellent pH-dependent drug-release behavior.In the cytotoxicity experiment,DTX-loaded NPs showed superior performance compared to the commercial drug,Taxotere?.TAPP-PLA-b-TPGS could generate singlet oxygen(1O2)species in irradiation of 660 nm wavelength light.Moreover,we found that a synergistic effect between PDT and DTX could enhance destruction of Hela cells.the star-shaped copolymer TAPP-PLA-b-TPGS has potential applications in the development of a new multi-modality treatment approach for cancer.