Determination of total and free concentration of propranolol in human plasma by displacement electrophoresis in a two-layer polyacrylamide gel using fluorimetric detection.
A new method based on displacement electrophoresis has been developed for the determination of the total and free concentration of propranolol, a beta-adrenergic blocker drug, in plasma. To determine the total concentration the drug is extracted from human plasma into a chloroform + heptane mixture in the presence of ammonia. After evaporation of the solvent mixture the residue is submitted to displacement electrophoresis in a glass tube containing a two-layer polyacrylamide gel. When the propranolol electrophoretically leaves the gel column it is transferred by a buffer flow to the cuvette of a fluorimeter for continuous detection and quantification. The concentration of the free non-protein bound drug can be determined by the same displacement electrophoresis technique following extraction of the plasma sample into the above organic solvent mixture in the absence of ammonia. Alternatively the extraction procedure can be exchanged for dialysis for 1 h. To decrease the risk that large size material might comigrate with propranolol two layers of polyacrylamide are used, one having small pores to retard such material. In addition, we use fluorimetric detection which means that many possible contaminants are not recorded and therefore do not affect a quantitative determination of propranolol.
Zelikman
I
I
Institute of Biochemistry, Uppsala University, Sweden.
Hjertén
S
S
D000641:Ammonia / Q000378:metabolism; D064753:Ammonium Hydroxide; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D006878:Hydroxides; D007202:Indicators and Reagents; D011433:Propranolol / Q000097:blood*; D013050:Spectrometry, Fluorescence
D006878:Hydroxides; D007202:Indicators and Reagents; D064753:Ammonium Hydroxide; D000641:Ammonia; D011433:Propranolol