Research Of The Influence Of Doxorubicin Loaded Melanin Particles On Drug Resistance Of Anaplastic Thyroid Cancer Cells

To research the influence of Doxorubicin Loaded Melanin Particles on drug resistance of Anaplastic Thyroid Cancer Cells.Methods Dopamine-melanin nanoparticles(MNPs)were synthesized as previously reported and Doxorubicin(Dox)was loaded onto MNPs.The loading efficiency and capacity of MNPs at different mass ratios of Dox to MNPs were determined by UV-Vis spectroscopy and the characterization of nanoparticles was acquired by transmission electron microscopy(TEM)and Brookhaven Zeta PALS analyzer.HTh74 and HTh74R cells were incubated with various concentrations of free Dox and Dox-MNPs(0、10、20、40、80、160mg/L).Cell viability was determined by MTT,and intracellular Dox fluorescent signal was determined by flow cytometry studies.Results The MNPs were successfully synthesized and the loading efficiency of Dox-MNPs decreased with the increasing mass ratio of Dox to MNPs.The loading efficacy peaked at 93.45%when the mass ratio was 0.167:1.At this mass ratio,the obtained Dox-MNPs had similar morphology to MNPs,and zeta potential and size distribution of Dox-MNPs were-13.79mV and 241.1±4.8nm.When incubated with HTh74R cells,Dox-MNPs induced significantly higher therapeutic efficacy than the same amount of free Dox,at concentrations higher than 20mg/L(P<0.05).The degree of uptake of Dox-MNPs in HTh74R cells was higher than the degree of uptake of DOX,similar to that in HTh74 cells(P<0.05).Conclusion The cellular uptake and therapeutic efficacy of the Dox-MNPs were significantly higher than those of free Dox at the same drug concentration in drug-resistant HTh74R cells.