Technique of handling neonatal blood samples for zinc analysis

Short segments of Chemfluor flexible Teflon tubing (2.38 mm ID) previously coated with sodium heparin (1,000 units/ml) serve as ideal containers in which blood from neonates can be collected for zinc analysis. The ends of the tube are plugged with Teflon TFE round beading so that the sample comes in contact only with Teflon and the risk of contamination is minimized. The heparin coating facilitates easy collection of the sample and separation of plasma by centrifugation. It does not contribute zinc to the specimen.