Electron microscopic characterization of neonatal platelet ultrastructure: effects of sampling techniques

Detailed ultrastructure of 720 neonatal platelets was systematically examined in 200-300 microliters cord blood samples from four normal term infants. There were no differences in platelet organelles between samples collected into standard sodium citrate anticoagulant and minimally heparinized samples collected into sodium citrate. Samples collected into EDTA showed significant differences from the other two solutions. There were also differences in organelle characteristics within a solution group, as time from sample collection to EM fixation varied. These results verify utilization of small minimally heparinized blood samples for examination of platelet ultrastructure. This system can now be expanded to the premature infant, where small blood sample requirements are essential, and minimally heparinized blood may be more readily available.