Studies On The Interaction Of Small Molecule Drugs With Bovine Serum Albumin By Spectroscopic And Voltammetric Methods

Protein plays an important part in humans and animals which perform most of the physiological activities and life phenomenon. Drugs is one of the important materials to regulate the body, cure diseases, and ensure the body. When entering the blood, drugs will generally bind serum albumin with varying degrees, which will affect the absorbance, metabolism, afficiency, pharmacological and toxicological effect of drugs. The researches on the interaction between drugs and serum albumin provide the premise foundation and the guarantee to understand the important role of protein in biological efficacy, drug molecular design and transformation. In this paper,poly L-aspartate modified electrodes(PLA/GCE) and poly L-glutamic modified electrodes(PLG/GCE) was fabricated by cyclic voltammetry method and fluorescent spectrometry method to study the photoelectric chemical and spectroscopic chemical behavior of interaction between isoniazid(INH), ascorbic acid(AA), and bovine serum albumin(BSA) systematically. By comparing the results of data in two methods, we obtain the combination of close degree, combining site, binding force,and binding constant with satisfactory results.The major problems to be solved in working processes are as follows: 1)Fabrication and characterizations of poly L-aspartate modified electrodes(PLA/GCE);2) Fabrication and characterizations of poly L-glutamic acid modified electrodes(PLG/GCE); 3) Study the electrochemical behavior of the interaction between INH with BSA; 4)Study the electrochemical behavior of the interaction between AA with BSA; 5) Study the photochemical behavior of the interaction between INH with BSA;6)Study the photochemical behavior of the interaction between INH with BSA.The main works and the detail achievements were as follows:1. The interaction between isoniazid(INH) and bovine serum albumin(BSA)was investigated using the self-made poly L-aspartate modified electrodes(PLA/GCE)by cyclic voltammetry. The binding constants of 1.544×104 L/mol can be calculated from the data obtained from cyclic voltammetry experiments. The number of theBinding sites is 1.137. Within the limits, the redox peak current of INH was proportional to the concentration of BSA, the linear range is1.00×10-9~5.00×10-5mol/L, and the detection limit is 5.00×10-10 mol/L. It has been applied to the determination BSA and INH in samples with satisfactory results.2. The interaction between isoniazid(INH) and bovine serum albumin(BSA)was investigated by fluorescent spectrometry. The binding constants of 1.479×104L/mol can be calculated from the data obtained from fluorescence quenching experiments. And the number of the binding sites is 1.177. The interaction of bovine serum albumin with INH was a single static quenching procedure. Within the limits,the fluorescence intensity changes of BSA linearly with the concentrations of INH,the linear range is 2.50×10-7~4.50×10-4 mol/L, and the detection limit is 1.0×10-7mol/L. It has been applied to the determination BSA and INH in samples with satisfactory results.3. The interaction between ascorbic acid(AA) and bovine serum albumin(BSA)was investigated using the self-made poly L-glutamic acid modified electrodes(PLG/GCE) by cyclic voltammetry. The binding constants of 1.761×104L/mol can be calculated from the data obtained from cyclic voltammetry experiments. And the number of the binding sites is 1.078. Within the limits, the redox peak current of AA was proportional to the the concentration of BSA, the linear range is2.50×10-8~5.00×10-5 mol/L, and the detection limit is 1.0×10-9 mol/L. It has been applied to the determination BSA and AA in samples with satisfactory results.4. The interaction between ascorbic acid(AA) and bovine serum albumin(BSA)was investigated by fluorescent spectrometry. The binding constants of 1.884×104L/mol can be calculated from the data obtained from fluorescence quenching experiments. And the number of the binding sites is 1.035. The interaction of bovine serum albumin with AA was a single static quenching procedure. Within the limits,the fluorescence intensity changes of BSA linearly with the concentrations of INH,the linear range is 2.50×10-7~3.50×10-4 mol/L, and the detection limit is 1.0×10-7mol/L. It has been applied to the determination BSA and AA in samples with satisfactory results.