Determination of XXXX in plasma of premature neonates using high-performance liquid chromatography.

@entity1046 @entity2715 @entity1626 @entity619 @entity1391
A high-performance liquid chromatographic assay is described for @entity619 in neonatal plasma. Samples (100 microliters) were extracted with @entity1046 (1.0 ml) containing 50 ng of @entity2715 . The mobile phase of @entity1626 -0.01 M @entity1391 buffer (pH 7.0) (45:55, v/v) was pumped at a flow-rate of 1.0 ml/min through an Ultrasphere ODS column (5.0 microns particles). Detection was by UV absorbance at 240 nm. Calibration plots were linear (r2 > 0.999) from 10-1000 ng/ml. Within-day and between-day precision (C.V.%, coefficient of variation) between 15-900 ng/ml was 1.21-20.6%. Inaccuracy was 7.7%, or less. The minimum quantifiable concentration (C.V. approximately 20%) was 15 ng/ml. Recovery (20-1000 ng/ml) exceeded 75%. Concomitant neonatal medication did not interfere.
