| There are many deficiencies in human’s treatments towards tumor diseases nowadays,such as poor therapeutic effect,large trauma to patients,and large toxic and side effects.Recently,an experimental therapy called photothermal therapy(PTT)has been proposed,which kills cancer cells through the combination of drug carrier’s photothermal conversion properties and anticancer drug under a specific wavelength laser.PTT is less invasive,simple to operate,and suitable for internal organs’ treatment.The aim of this paper is to acquire a photothermal agent with good biocompatibility and excellent photothermal properties.The effect of different surface modifiers(polyethylene glycol,PEG)and the effect of MoS2 content on the properties of the complexes are investigated.Also,its drug loading,drug release properties and cytotoxicity as well.The main research contents and conclusions of this paper are as follows:The GO-MoS2 nano complex was acquired by one-step hydrothermal method.PEGs were grafted onto the complex by the reaction of-NH2 and-COOH.According to the surface morphology,size and agglomeration of the samples,the effects of three kinds of PEG modifiers were compared to determine 6arm-PEG15k-NH2 as the best modifier;the photothermal properties of the complexes were then investigated.At a concentration of 50 μg/ml,after GM6 was irradiated by NIR for 10 min under 2.0 W/cm2,the temperature of the system was 50.1℃(△T=19.2℃),while the system temperature of G06 under the same conditions was 40.8℃(△T=9.9℃).G06’s performance is weaker than the prepared complex.The effects of different MoS2 contents on the photothermal conversion performance and cytotoxicity of the samples were investigated.It was concluded that the higher the MoS2 content of the sample,the stronger the photothermal conversion ability and the greater cytotoxicity exhibited;meanwhile,with the existence of near-infrared laser(NIR),the photothermal conversion capacity of each sample was enhanced.Under NIR power of 2.0 W/cm2,the GM6 with a MoS2 mass ratio of 27.5%at a concentration of ≥50 μg/ml,the relative cell viability was around 30%.The sample has a relatively moderate cytotoxicity and is suitable for selection as a follow-up sample.Doxorubicin hydrochloride(DOX)was used as a loading drug to evaluate the drug loading and release properties of the GO-MoS2 complex.DOX would be easily loaded under alkaline conditions(pH = 8.0).The drug loading rate of GM6 at a DOX concentration of 1.0 mg/ml was 81.55%,whereas GO6 group was only 69.08%.Acidic conditions(pH=5.0)facilitate the release of DOX.The drug release rate of GM6-DOX at 24 h is 66.72%,while that of G06-DOX is only 47.08%.The NIR laser can promote drug release,at a NIR laser power of 1.8 W/cm2,the drug release rates of GM6-DOX and GO6-DOX were 78.03%and 59.07%,respectively.The prepared complex exhibits better drug loading and release performance than GO.The toxicity evaluation and cell uptake behavior of drug-loaded complexes were investigated with Hela cancer cells,demonstrating that GM6-DOX exhibits higher toxicity compared to GO6-DOX.When the drug concentration was 15 μg/ml,under the NIR power of 2.0 W/cm2,the relative viability of Hela cells in the GM6-DOX experimental group was only 59%,while the GO6-DOX experimental group was still higher than 70%,which has a poor ability of eliminating cancer cells;NIR laser can enhance the entry of GM6-DOX’s loaded drug to get into the nucleus of Hela cells and inhibit the transcription of DNA. |
