Thermodynamic and kinetic studies for the interaction of cephalexin with albumin

This work aim to get information about the binding of cephalexin(antibiotics) withalbumin, and the influence of the solvent polarity and ionic strength on it by using UV-visbspectrophotometric measurements in phosphate buffer solution pH (7.4), and at threedifferent temperatures, (290, 300, 310)K .The UV absorption shows a change and a shift inthe absorbency and a shift in albumin and cephalexin peaks, the two changes are indicativeof complex formation. The stoichiometry of the interaction were calculated by the methodof continuous variations which was1:1at pH 7.4.The equilibrium constant was calculated atthree different temperature (290,300,310)K and the thermodynamic parameter such as ΔG,ΔH and ΔS also calculated. The kinetic studies for this interaction follows first orderequation with a rat constant value of 13.8×10-4 min-1.