Simultaneous determination of hemoglobin and coproporphyrin by second derivative differential spectrophotometry: application to the diagnosis of meconium aspiration.

ABSTRACT

We describe a simple, fast method for simultaneous measurement of hemoglobin and coproporphyrin in urine and amniotic fluid, by second-derivative differential spectrophotometry. Both pigments were determined in biological samples without prior extraction. Despite the slightly overlapping spectra, the method permitted satisfactory resolution and avoided interspectral interference. Its sensitivity, sufficiently good, allowed to detect hemoglobin and coproporphyrin in slightly pathological urine and amniotic fluid as an aid to the diagnosis of meconium aspiration.