An oxygen electrode system, supplied as an attachment to the Radiometer Astrup micro equipment for blood pH determination (AME I), has been investigated. Determination of blood oxygen tension using this electrode system has been compared with tension measurements using an established Bishop type oxygen electrode and satisfactory agreement was found. The storage of blood for routine estimation o...

The separation and determination of two anthraquinones, emodin and chrysophanol, and two bianthraquinones, cassiamin A and cassiamin B, were achieved by capillary electrophoresis (CE). The running electrolyte used in this method was 0.05 M hydroxypropyl-gamma-cyclodextrin in 0.1 M borate buffer (pH 9) containing 10% acetonitrile, with an applied voltage of 20 kV. Application of this technique i...

Esomeprazole is a new chromogenic reagent used for the determination of nickel (II) by direct spectrophotometric method. Esomeprazole forms a greenish yellow colouredcomplex with nickel (II) at pH 5. The method obeys Beer’s law over 0.139 – 1.394 μg mL -1 , Sandell’s sensitivity is 0.0029mg/cm 2 and molar absorptivity value (ε = 2.5 x 10 4 L mol -1 cm -1 ). The method is useful for determinatio...

In 1945, a method was described by Bonsnes and the writer (1) for the determination of urinary creatine which involved only the addition of picric acid to dilute urine solutions and heating in a boiling water bath. An 80 per cent conversion of creatine to creatinine was obtained. The method has now been modified to achieve 100 per cent conversion, on the basis of Clark and Thompson’s recent stu...

MOTIVATION The identification of suitable conditions for crystallization is a rate-limiting step in protein structure determination. The pH of an experiment is an important parameter and has the potential to be used in data-mining studies to help reduce the number of crystallization trials required. However, the pH is usually recorded as that of the buffer solution, which can be highly inaccura...