Photothermal Effect And Biocompatibility Of Ultra-Small CuS@BSA Nanoparticle

With the development of nanomaterials,more nanomaterials with high quality physicochemical properties have been developed.Among them,local surface plasmon resonance?LSPR?nanomaterials have excellent optical properties and are widely used in biomedical imaging and treatment research.Copper sulfide nanomaterials is one of them,because its LSPR peak falls in the near infrared?NIR?region,suitable for deep bioimaging and photothermal therapy.Despite the many biomedical applications,the photothermal effect,biocompatibility and toxicity of copper sulphide have not been systematically studied.In this paper,we synthesized ultra-small biocompatible copper sulfide nanoparticles coated with Bovine serum albumin?BSA?and CuS@BSA.The physical characteristics of CuS@BSA were characterized,and the good photothermal conversion efficiency,as well as the in vitro and in vivo toxicity studies,were systematically studied.The main contents are as follows:1.Synthesis and characterization of copper sulfide nanoparticlesIn this paper,CuS@BSA nanoparticles were synthesized by aqueous phase method,and their absorption spectra,size and size were analyzed.The results show that the absorption spectrum of CuS@BSA nanoparticles is 1060 nm and the size is about 8 nm.The biological stability of 72 h is good,and its absorption spectrum belongs to the near-infrared region,which can be used for near-infrared photothermal therapy.Therefore,we studied the photothermal effect of CuS@BSA nanoparticles.2.Photothermal effect of copper sulfide nanoparticlesThe synthesized CuS@BSA nanoparticles were diluted with ultrapure water to 22.5?g/mL,45?g/mL,90?g/mL,180?g/mL,ultrapure water as a blank control,and irradiated with a 1064 nm laser for 180 s.The infrared imager showed that the photothermal conversion effect of CuS@BSA nanoparticles was very good.At a concentration of 22.5?g/mL,the temperature was able to reach 46°C for 180 s,which has reached the temperature of killing cancer cells.At a concentration of 180?g/m L for 180 s,the temperature can be as high as65°C.The photothermal conversion efficiency of CuS@BSA nanoparticles is as high as69.37%,and the molar extinction coefficient is 7.06×10⁹ M^-1 cm^-1.3.In vitro biological effects of copper sulfide nanoparticlesThe HeLa cells were incubated with CuS@BSA nanoparticles for 24 or 48 hours.The cytotoxicity of CuS@BSA nanoparticles was detected by MTT and apoptosis kit.The results showed that the effect of CuS@BSA nanoparticles on the activity of HeLa cells,C uS@BSA nanoparticles treated cells within 24 hours,the concentration ranged from 0-45?g/mL,the cells proliferated normally,and the treatment time was 48 hours.When the concentration of CuS@BSA nanoparticles was higher than 45?g/mL,it showed obvious Cytotoxicity;at this concentration,cel s treated with CuS@BSA nanoparticles for 48 hours induced apoptosis.4.In vivo biological effects of copper sulfide nanoparticlesThe 5.5 mg/kg CuS@BSA nanoparticles were injected into the mice through the tail vein.The PBS solution was used as a blank control group,and the body weight trend was observed after 2 h,6 h,12 h,24 h,and 30 days,respectively.Coefficient,blood index,organ photothermal,ICP-MS and other indicators explore the distribution of CuS@BSA nanoparticles into mice and the toxic effects.The study found that when the concentration of CuS@BSA nanoparticles was 5.5 mg/kg at 2 h,6 h,12 h,24 h,CuS@BSA nanoparticles were mainly distributed in organs such as liver,spleen and kidney.After 30 days,the organ coefficient,blood index,ICP-MS and other indicators did not differ from the control group.In this paper,we mainly synthesize a CuS@BSA nanoparticle with a size of about 8 nm,which has excellent photothermal effect,and has great po tential for application in biomedical photothermal therapy in the future.The research results are for promoting CuS@BSA nanoparticles.References are provided for safety applications in the biomedical field.