Preparation Of Triphenylphosphine Nanoplatinum And Its Effect On The Viability Of Human Breast Cancer Cells

Objective:Through the design of tumor microenvironment stimulation-responsive triphenylphosphine nano-platinum drug for the treatment of breast cancer,it provides a new solution to the problem of drug resistance in clinical breast cancer.Methods: Preparation of nano-platinum drugs(Pt-NPs).Step 1:Cisplatinum was oxidized to obtain tetravalent platinum prodrug CisPt(IV),and then the reaction was condensation with triphenylphosphonic acid to obtain triphenylphosphonic acid-tetravalent platinum prodrug CisPt(IV)-TPP.The second step: 1,2,4,5-cyclohexane tetraformic dianhydride(CDTA)was polymerized with 2-hydroxyethyl disulfide HO-SS-OH to form amphiphilic polymer drug carrier m PEG-SS-m PEG.The third step:The target nano-platinum drug was obtained from anionic polymer carrier m PEG-SS-m PEG and cationic tetravalent platinum precursor CisPt(IV)-TPP with nanoprecipitation.The particle size,dispersion(PDI)and potential value of Pt-NPs were determined by dynamic light scatterer DLS.The platinum content in aqueous solution was measured by ICP-MS,and the loading rate was calculated.The morphology was characterized by transmission electron microscopy.The rhodamine B labeled NPs were used to detect the endocytosis of tumor cells to Pt-NPs with flow cytometry.MTT assay was used to detect the survival rate of tumor cells to reflect the anti-tumor effect of Pt-NPs.Results:A 5.6 ppm in the Nuclear Magnetic Resonance(NMR)is the hydrogen peak of the amino group of tetravalent platinum,which indicated that CisPt(IV)had been successfully prepared by cisplatinum oxidation.A 7.5-8.5 ppm in NMR is the hydrogen peak on the benzene ring after the introduction of triphenylphosphine,and about 6.5 ppm is the hydrogen peak of tetravalent platinum amino.The molecular weight is1023 in the mass spectrum,indicating that CisPt(IV)-TPP has been successfully synthesized.In the NMR spectrum of m PEG-SS-m PEG,methylene hydrogen peak at about 4.2 ppm of esteryl oxygen ortho and methylene hydrogen peak at about 3.5 ppm of polyethylene glycol oxygen ortho can indicate that m PEG-SS-m PEG has been successfully synthesized,and its degree of polymerization is about 25.When the mass ratio of CisPt(IV)-TPP and m PEG-S-S-m PEG was 1:5,the particle size of Pt-NPs obtained was the smallest,with an average particle size of 129 nm,PDI of0.087,surface point value of-14.97 m V,and platinum loading rate of 8.3%.In the in vitro drug release experiment,Pt-NPs was stable at p H 5.0 and p H7.4,and was rapidly released in the presence of a large amount of sodium ascorbate.In the endocytosis test,Pt-NPs labeled with Rhodamine B was used to treat cisplatin-resistant human breast cancer cells MCF-7/DDP,and the average intracellular fluorescence intensity value in the cell increased with time,indicating that the transmembrane amount of nano-platinum drug increased with time,Which indicated that method overcomes drug resistance in breast cancer.In the survival rate test of tumor cells by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT),cisplatinum,CisPt(IV)-TPP and PtNPS were used to treat human breast cancer cells MCF-7 and human breast cancer cisplatin-resistant cells MCF-7 /DDP,and the anti-tumor effects were Pt-NPs > CisPt(IV)-TPP > cisplatin.Conclusion: The successfully prepared tumor microenvironment stimulation-responsive triphenylphosphine nanoplatinum has good killing effect on cisplatin-resistant human breast cancer cell line MCF-7/DDP.