Proportion of hemoglobin S in blood, as determined from solubility measurements.

Abstract

We exploited the concentration dependence of hemoglobin S on its solubility in concentrated phosphate buffer to determine the percentage of hemoglobin S or hemoglobin A in whole blood or hemolysates. A sample is incubated for 1 h at 37 degrees C in "SickleQuik" (General Diagnostics) tubes, and the absorbance of the aqueous phase is then measured at 555 nm and 650 nm, the latter wavelength to correct for turbidity. The fractional hemoglobin S or hemoglobin A content is read from standard-curve data on mixtures of hemoglobin A and hemoglobin S. Such curves can be prepared with the use of hemoglobin A alone, because under our conditions all hemoglobin S is precipitated. The curve is reproducible for up to three weeks. Day-to-day CVs ranged from 1.8% at 10% hemoglobin S to 8.1% at 68% hemoglobin S. For similar concentration ranges, day-to-day CVs for electrophoresis, with densitometry, ranged from 4.9% to 18%. Results on 29 patients are presented. We recommend the method for rapid quantification of hemoglobin S percentage for patients with sickle cell disease in acute-care situations.

Discordance between self-reported premarital and post-marital parental sickle cell status

“…Other affordable and reliable screening methods to minimize "false reports" in resource-limited countries include the use of insoluble hemoglobin add-on (modified HST) [15,16]. This was noted to be the most accurate when compared with DNA genotyping results.…”

Novel Test Method (Sickle Confirm) to Differentiate Sickle Cell Anemia from Sickle Cell Trait for Potential Use in Developing Countries

“…Some methods recognized that upon centrifugation, the insoluble HbS rose to the top of the tube proportionally reducing the red color of the on August 2 2020 http://hwmaint.clsjournal.ascls.org/ Downloaded from solution which was analyzed visually to determine zygosity. [11][12][13] In 1983 Bowie and Dohnal developed another modified hemoglobin solubility technique to determine zygosity involving the "SickleQuik" test kit followed by centrifugation and spectrophotometric measurements. The "SickleQuik" method is a biphasic test involving aqueous and organic layers that utilizes the organic solvent toluene.…”

“…The aqueous phase is identical to the standard hemoglobin solubility test while the organic layer assists in capturing the precipitated hemoglobin. 13 Lastly, Scabet et al in 1986 also developed a modified version of the hemoglobin solubility test utilizing filtration and spectrophotometric absorbance measurements to calculate HbS levels and determine sickle cell zygosity. An equal volume of whole blood collected in EDTA was added to both a hemoglobin solubility tube (saponin, sodium hydrosulfite and a salt solution) and a tube of dH20.…”