ABSTRACT
The effect of temperature on the resolution of (RS)-sotalol by immobilized cellobiohydrolase I (CBH I) was studied between 5 and 40 degrees C and Van 't Hoff plots of ln k versus 1/T were acquired at different pH values of the aqueous mobile phase and in the presence of varying organic cosolvents. The elution order of the enantiomers reverses in the range between 17 and 28 degrees C. Beyond this range, enantioseparations with comparatively high resolution factors are achieved either by decreasing or by increasing the temperature. The composition of the mobile phase influences the "crossover" temperature as well as the character of the global adsorption process of the (R)-(-)-enantiomer. Under certain conditions, (R)-(-)-sotalol exhibits an unusual endothermic adsorption behavior. Its retention time increases with increasing temperature. At room temperature (23 degrees C) the enantiomeric elution order can also be regulated by the solvent additive.
Subject(s)
Adrenergic beta-Antagonists/isolation & purification , Cellulase/chemistry , Sotalol/isolation & purification , Cellulose 1,4-beta-Cellobiosidase , Chromatography, High Pressure Liquid/instrumentation , Spectrophotometry, Ultraviolet , Stereoisomerism , Temperature , ThermodynamicsABSTRACT
Orellanine is the main toxin of various Cortinarius mushrooms and responsible for their nephrotoxicity. The present study was undertaken to estimate the value of haemoperfusion in Cortinarius intoxications. The efficiency of the haemoperfusion materials activated charcoal (DHP-1) and Amberlite XAD 4 resin at removing orellanine from plasma was tested in an in vitro model. Quantification of the toxin in plasma samples was carried out following a previously reported fluorodensitometric TLC method. Orellanine is sufficiently bound to both haemoperfusion materials. However, the rate of orellanine adsorption was four times higher on activated charcoal (DHP-1) compared to Amberlite XAD 4 resin.
