SF Samples Research Articles

Spinal fluid kinetics of morphine and heroin

Nine patients undergoing cardiopulmonary bypass surgery were given either 2 mg diamorphine or 2.5 mg morphine by intrathecal injection. Spinal fluid (sf) samples were collected over 25 min and drug concentrations measured by HPLC. Concentrations in sf were about 4000 times as great as after 1 mg/kg IV morphine. The kinetic properties of morphine and heroin in sf differed; diamorphine was removed from sf much more rapidly than morphine. Lipophilic opiates may be safer for intrathecal use because of the shorter life of substantial drug concentrations in the mobile sf phase.

Quantitation of fetal hemoglobin by densitometry.

Abstract Densitometry of hemoglobins separated by cellulose acetate electrophoresis has become a routine procedure for quantitating hemoglobins in hospital and hemoglobinopathy screening laboratories. Although the alkali denaturation technique is the analytic method of choice for the quantitation of fetal hemoglobin (Hb F), many laboratories have been using densitometry to report Hb F levels. To evaluate the accuracy of densitometry for Hb F quantitation, 31 Hb AF samples and 16 Hb SF samples were separated by cellulose acetate electrophoresis. Densitometric Hb F levels were compared with the levels determined by the Singer alkali denaturation test. Densitometry was found to be unsatisfactory for quantitation of Hb F.