Validated HPLC method for determination of temozolomide in human plasma

Area of Science:

• Analytical Chemistry
• Pharmacology
• Biochemistry

Background:

• Temozolomide (TMZ) is a crucial chemotherapeutic agent.
• Accurate quantification of TMZ in biological matrices is essential for pharmacokinetic studies.
• Existing methods may have limitations in sensitivity, stability, or applicability.

Purpose of the Study:

• To develop and validate a sensitive and reliable bioanalytical method for determining temozolomide (TMZ) concentrations in human plasma.
• To ensure the method's suitability for supporting clinical pharmacokinetic investigations of TMZ.

Main Methods:

• Liquid-liquid extraction of TMZ from acidified human plasma (pH < 3) to prevent degradation.
• Quantification using a C18 column with isocratic elution (aqueous acetic acid/methanol).
• Theophylline employed as an internal standard for enhanced accuracy.

Main Results:

• The method demonstrated linearity over a concentration range of 0.10-20.00 microg/mL.
• Validation parameters met all acceptance criteria, indicating high accuracy and precision.
• Temozolomide showed stability in acidified plasma for at least 50 days at -14°C or -65°C.

Conclusions:

• A robust and validated bioanalytical method for human plasma TMZ determination has been successfully developed.
• The method's stability, accuracy, and precision make it ideal for pharmacokinetic studies following oral TMZ administration.