ABSTRACT
A mathematical model was developed for the study of the D,L-dansylamino acid retention mechanism in reversed-phase liquid chromatography using a C18 column as a stationary phase and human serum albumin (HSA) as an eluent modifier. The solute retention factor is dependent on the HSA concentration in the eluent as well as the binding constant of the guest-HSA complex. A determination of the degree of complexation n(c) (the percent of the complexed guest) could be carried out. Different Van 't Hoff plot shapes of the degree of complexation were observed with different eluent pH, confirming a change in the solute complexation mechanism for physiological pH (between 7-7.5). Enthalpy-entropy compensation was also analysed in relation to this mathematical model to confirm the solute complexation behavior with HSA. These results finally confirmed that at physiological pH and temperature (approximately 35 degrees C) values the HSA was in a favorable structural conformation for its binding with a great majority of drugs.
Subject(s)
Chromatography, High Pressure Liquid/methods , Serum Albumin/chemistry , Humans , Hydrogen-Ion Concentration , Reproducibility of Results , Spectrophotometry, Ultraviolet , Temperature , ThermodynamicsABSTRACT
The contamination of air of a 50 m3 operating room has been analyzed after three and half hours of halothane enaesthesia with a closed circle system and an opened system. The analysis has been made by gaz chromatography. Concentrations of Halothane found during the use of an opened system are 100 to 120 times the allowable norms in U.S.A. After using the closed circle system, the analysis of air does not reveale any trace of Halothane.
