The advantages of cell lysis before blood sample preparation by extraction for HPLC propofol analysis

Abstract

Propofol (2,6-diisopropylphenol) is a short-acting drug with a large volume of distribution and high body clearance. It is suitable both for the induction of anaesthesia by bolus injection and the maintenance of anaesthesia by repeated injections or a continuous infusion. Examining the drug concentration its analysis in whole blood is recommended. This results from the fact that propofol molecules strongly bind with plasma proteins and cellular blood constituents and blood composition variations are observed between individuals or in different disease states or resulting from transfusion etc. In most cases the HPLC analysis follows the extraction of samples. The degree of propofol binding with blood cells can be different, depending on the blood type, and it can change in time, which may affect the results of the analysis. The paper discusses and shows the necessity of blood cell lysis before the extraction procedure. The cell lysis makes possible to determine the total amount of propofol in blood independently of the degree of propofol binding with cellular blood constituents and its changes.

A rapid and simple HPLC method for the analysis of propofol in biological fluids

“…The whole blood to plasma distribution ratio ranged from 1.64 to 2.02. This result is in accordance with the data reported by Dawidowicz and Fornal [15] in human biological samples.…”

“…Plasma was decanted and stored at −20 • C until analysis. For whole blood analysis, blood was immediately lysed by freezing at −20 • C. As reported by Dawidowicz and Fornal [15], the lysis seems to be necessary to estimate the total amount of propofol in whole blood.…”

A rapid and simple HPLC method for the analysis of propofol in biological fluids

“…The whole blood to plasma distribution ratio ranged from 1.64 to 2.02. This result is in accordance with the data reported by Dawidowicz and Fornal [15] in human biological samples.…”

“…Plasma was decanted and stored at −20 • C until analysis. For whole blood analysis, blood was immediately lysed by freezing at −20 • C. As reported by Dawidowicz and Fornal [15], the lysis seems to be necessary to estimate the total amount of propofol in whole blood.…”

Novel biomarker pipeline to probe the oxidation sites and oxidation degrees of hemoglobin in bovine erythrocytes exposed to oxidative stress

“…After removing plasma supernatant, the erythrocytes were rinsed three times with 1.5% NaCl solution (1:1, v/v) and sediment at 2000 g , at 4°C for 15 min. Subsequently, these samples were lysed and vortex‐mixed with 3 vols of cold 5 mmol/L phosphate buffer (pH 7.4), containing 0.3% NaCl and 5 mmol/L ascorbic acid (Dawidowicz and Fornal, ; Thevis et al ., ). Then the lysates were centrifuged at 7000 g for 10 min and the supernatants were collected with Eppendorf tubes.…”

Changes in drug plasma concentrations of an extensively bound and highly extracted drug, propofol, in response to altered plasma binding

“…The concentration of propofol was measured by HPLC with the method of Plummer 29 with minor modification for plasma (0.1 mL), lysed whole blood 30 (0.5 mL [0.1 mL whole blood plus 0.4 mL distilled water]), or dialysate (0.5 mL). Each sample (0.1–0.5 mL) with internal standard (thymol in methanol, 20 μL, 5 μg · mL −1 ) was buffered with 1 mL of 0.1‐mol/L phosphate buffer (pH 7.4) and extracted on a rotary mixer for 15 minutes with 5 mL of n ‐hexane.…”

A rapid and simple HPLC method for the analysis of propofol in biological fluids

“…The whole blood to plasma distribution ratio ranged from 1.64 to 2.02. This result is in accordance with the data reported by Dawidowicz and Fornal [15] in human biological samples.…”

“…Plasma was decanted and stored at −20 • C until analysis. For whole blood analysis, blood was immediately lysed by freezing at −20 • C. As reported by Dawidowicz and Fornal [15], the lysis seems to be necessary to estimate the total amount of propofol in whole blood.…”

Novel biomarker pipeline to probe the oxidation sites and oxidation degrees of hemoglobin in bovine erythrocytes exposed to oxidative stress

“…After removing plasma supernatant, the erythrocytes were rinsed three times with 1.5% NaCl solution (1:1, v/v) and sediment at 2000 g , at 4°C for 15 min. Subsequently, these samples were lysed and vortex‐mixed with 3 vols of cold 5 mmol/L phosphate buffer (pH 7.4), containing 0.3% NaCl and 5 mmol/L ascorbic acid (Dawidowicz and Fornal, ; Thevis et al ., ). Then the lysates were centrifuged at 7000 g for 10 min and the supernatants were collected with Eppendorf tubes.…”

Changes in drug plasma concentrations of an extensively bound and highly extracted drug, propofol, in response to altered plasma binding

“…The concentration of propofol was measured by HPLC with the method of Plummer 29 with minor modification for plasma (0.1 mL), lysed whole blood 30 (0.5 mL [0.1 mL whole blood plus 0.4 mL distilled water]), or dialysate (0.5 mL). Each sample (0.1–0.5 mL) with internal standard (thymol in methanol, 20 μL, 5 μg · mL −1 ) was buffered with 1 mL of 0.1‐mol/L phosphate buffer (pH 7.4) and extracted on a rotary mixer for 15 minutes with 5 mL of n ‐hexane.…”

A rapid and simple HPLC method for the analysis of propofol in biological fluids

“…The whole blood to plasma distribution ratio ranged from 1.64 to 2.02. This result is in accordance with the data reported by Dawidowicz and Fornal [15] in human biological samples.…”

“…Plasma was decanted and stored at −20 • C until analysis. For whole blood analysis, blood was immediately lysed by freezing at −20 • C. As reported by Dawidowicz and Fornal [15], the lysis seems to be necessary to estimate the total amount of propofol in whole blood.…”

Novel biomarker pipeline to probe the oxidation sites and oxidation degrees of hemoglobin in bovine erythrocytes exposed to oxidative stress

“…After removing plasma supernatant, the erythrocytes were rinsed three times with 1.5% NaCl solution (1:1, v/v) and sediment at 2000 g , at 4°C for 15 min. Subsequently, these samples were lysed and vortex‐mixed with 3 vols of cold 5 mmol/L phosphate buffer (pH 7.4), containing 0.3% NaCl and 5 mmol/L ascorbic acid (Dawidowicz and Fornal, ; Thevis et al ., ). Then the lysates were centrifuged at 7000 g for 10 min and the supernatants were collected with Eppendorf tubes.…”

Changes in drug plasma concentrations of an extensively bound and highly extracted drug, propofol, in response to altered plasma binding

“…The concentration of propofol was measured by HPLC with the method of Plummer 29 with minor modification for plasma (0.1 mL), lysed whole blood 30 (0.5 mL [0.1 mL whole blood plus 0.4 mL distilled water]), or dialysate (0.5 mL). Each sample (0.1–0.5 mL) with internal standard (thymol in methanol, 20 μL, 5 μg · mL −1 ) was buffered with 1 mL of 0.1‐mol/L phosphate buffer (pH 7.4) and extracted on a rotary mixer for 15 minutes with 5 mL of n ‐hexane.…”