Research On The Interaction Of Antibiotics And Macromolecules With Antibiotic Drug Analysis Method

In this paper, norfloxacin, cefixime, penicillin V potassium were studied by the method of stripping voltammetry and fluorescence spectroscopy. The systems’ properities of interaction antibiotics with macromolecules including electrochemical performance, spectral characteristics, mechanism, factors and reaction conditions were studied. At the same time the new methods of pharmaceutical analysis were established and applied to the actual samples.(1) The interaction between norfloxacin and 5-sulfosalicylic acid has been analyzed by electrochemical method under the enrichment potential was-0.1V, which provided a new way to test the content of norfloxacin. As a result, when the current was0.2m A or 0.5m A, the linear range was 1.0×10-6~2.0×10-4 mol/L or 4.0×10-5~2.0×10-4mol/L, the detection limit was 1.608×10-6mol/L and the relative standard deviation was1.10%. This system was used to detect the content of norfloxacin capsules, recoveries were at 95%~100%. Compatibility in vitro experiment shows that both of the drugs interacted with each other, so combining the two drugs may be adverse reactions in clinical medicine or life.(2) The reaction between cefixime and bovine serum albumin(BSA) has been studied under normal physiological conditions by fluorescence spectroscopy. The fluorescence quenching constants, the binding sites, the binding constants, the binding distance and the reliminary thermodynamic parameters were calculated out at different temperatures. The results indicated that: they were quenched by passing through a dynamic combination of hydrophobic interaction, the ratio was 1:1; the value of the binding distance was 2.112nm; cefixime had a certain effect on the conformation of BSA, which had a store for cefixime and transit functions. At the same time a new method for the determination of cefixime was established that the linear range was0.080~0.560μg/m L, the detection limit was 0.345μg/m L and the relative standard deviation was 3.01%. This method can be applied to the analysis of cefixime capsules.(3) The interaction between penicillin V potassium and BSA has been studied bystripping voltammetry. A non-electrical-active complex was formed by the electrostatic force between penicillin V potassium and BSA. The binding ratio was 1:1; the binding constant β was 3.35×106L/mol; the binding number n was 1. A new method for the determination of penicillin V potassium was established that the linear range and the detection limit were 1.0×10-4~6.0×10-3mol/L, 1.085×10-4mol/L, the relative standard deviation was 2.20%. Urine samples were spiked for recovery experiments and recoveries were from 95% to 105%.