Centrifugal microfiltration: a simple way to enhance the sensitivity of the classical aluminium oxide adsorption method of fluorimetric catecholamine determination.

With the aid of a device utilizing filtration at high pressure produced by centrifugation and constructed from a disposable syringe, the process of solid--liquid separation was greatly simplified. The use of this device facilitated considerably the aluminium oxide adsorption method of catecholamine determination: practically 100% recovery from the adsorbent in as little as 100 microliter of eluent could be easily achieved, and the total amount of catecholamines could be transferred into the microcuvette of a fluorimeter. This resulted in an almost 10-fold increase of sensitivity.