Micro stirring rod

Micro stirring rods are prepared by sealing capillaries or drawing out glass rods one end of the rod can be melted to form a small ball. 

Serum pseudo-cholinesterase (referred to hereafter as serum cholinesterase) activities were determined from a five minute reaction period at room tenperature with a modification of the method of EUman et 2Q. ( ). Briefly, a 10 pi 2d.iguot of serum ves added to both a reference and sample cuvette ocxitaining 3.0 ml of 5,5-dithiobis-(2-nltrobenzoate) (DDO buffer (0.25 mM in ph 8.0, 0.1 M sodium phos te buffer) and mixed with a micro-stirring rod. Die reaction ves steurted in the sample cuvette by the addition of 20 pi of aoetylthiochollne iodide (78 nM) and stirred. The reference cuvette received 20 pi of distilled water in place of substrate. Absorbance was measured at 412 im over a five minute period and the rate calculated from the slope of the derived curve. 

---