| Because of antibacterial,anti-inflammatory,anti-cancer and other drug activities,curcumin have been applied in the clinic.Poor solubility,easily decompose and other problems have limited the clinical application of curcumin.Preparing curcumin into curcumin quantum dots can improve stability,solubility and drug activity of curcumin,which can solve the problems of curcumin in clinical applications.At present,platinum anti-cancer drugs were most widely used in the clinical treatment of cancer.Curcumin can be used in combination with platinum anticancer drugs in the treatment of cancer.The research of the absorption and transportation process of curcumin quantum dots and platinum anticancer drugs in the human body were not very clear.Studying the interaction between drugs and proteins will help to understand the pharmacological effects.In this paper,the interaction between curcumin quantum dots and oxaliplatin,carboplatin with bovine serum albumin（BSA）was studied by fluorescence spectroscopy,the results are as follows:（1）In order to improve the solubility and stability of curcumin,ultrasonic assisted hydrothermal synthesis was used to prepare curcumin quantum dots.And the characteristics of curcumin quantum dots were shown.The effects of p H,illumination,heating temperature,heating time and ultrasound time on the spectrum of curcumin quantum dots were investigated.The results showed:the size of the curcumin quantum dots was about 2 nm,its solubility was significantly improved compared with curcumin.Absorption peak was located at 264 nm and 332 nm.The fluorescence peak is located at 458 nm when excited at 340 nm.Curcumin quantum dots had obvious excitation wavelength dependence when excited by different wavelengths.These results were consistent with the properties of carbon quantum dots.The fluorescence intensity and fluorescence lifetime of carbon quantum dots were relatively stable in the acidic and neutral environments,rising significantly in the weak alkaline environment and decreasing in the strong alkaline environment.The fluorescence intensity and fluorescence lifetime of carbon quantum dots were basically unchanged after 240 min of illumination and great photostability.The optimal synthesis condition for curcumin quantum dots was heating at 180°C for 10h after sonication for 10 min.（2）The interaction between curcumin quantum dots and BSA at 300 K and 310K were studied.The results showed that curcumin quantum dots had a dynamic quenching effect on BSA.The interaction doesn’t occur in the ground state,but in the excited state.The quenching efficiency increases with temperature arise.The quenching resulting in a significant decrease in the fluorescence lifetime of BSA.（3）The interaction between oxaliplatin and carboplatin with BSA at 296 K and310 K was studied.The results showed that oxaliplatin and carboplatin interacted with BSA,and the binding constants of oxaliplatin and BSA at 296 K and 310 K were2.65×104L·mol-1and 3.55×104L·mol-1.The binding constants of carboplatin and BSA at 296 K and 310 K were 4.22×104L·mol-1and 5.26×104L·mol-1.The number of binding sites between oxaliplatin,carboplatin and BSA both were 1.Based on hydrophobic force of the binding drug-BSA complex,the binding position of oxaliplatin and carboplatin with BSA could be the 212th tryptophan residue in BSA. |
