Simplified GLC assay for lidocaine in plasma

Area of Science:

• Analytical Chemistry
• Pharmacology
• Clinical Chemistry

Background:

• Accurate quantification of lidocaine in plasma is crucial for therapeutic drug monitoring.
• Existing methods may be time-consuming or lack sensitivity for low-level detection.

Purpose of the Study:

• To develop and validate a simple, rapid gas-liquid chromatography (GLC) method for determining lidocaine concentrations in human plasma.
• To establish the sensitivity and linearity of the developed method for clinical application.

Main Methods:

• Plasma samples were deproteinized and centrifuged.
• Lidocaine and mepivacaine (internal standard) were extracted into carbon disulfide after alkalinization.
• Gas-liquid chromatography with a flame-ionization detector was employed for analysis.

Main Results:

• Linear concentration-response curves were achieved for lidocaine in the 1-6 microgram/ml range.
• The method demonstrated sensitivity to quantify lidocaine at 250 ng/ml using a 1-ml plasma sample.
• Mepivacaine served as an effective internal standard.

Conclusions:

• The developed GLC method is simple, rapid, and sensitive for plasma lidocaine determination.
• This assay is suitable for therapeutic drug monitoring and pharmacokinetic studies.
• The method's ability to detect low lidocaine concentrations enhances its clinical utility.