Pentobarbital quantitation using immunoassays in Reye's syndrome patient serum

Area of Science:

• Clinical Chemistry
• Toxicology
• Pharmacology

Background:

• Accurate measurement of serum pentobarbital is crucial for managing Reye's syndrome.
• Existing immunoassay methods require adaptation for precise serum pentobarbital quantitation.

Purpose of the Study:

• To adapt and evaluate immunoassay techniques for accurate serum pentobarbital measurement in Reye's syndrome patients.
• To compare the performance of adapted immunoassays against a high-performance liquid chromatography (HPLC) reference method.

Main Methods:

• Modified urine enzyme-multiplied immunoassay technique (EMIT) Dupont aca barbiturate screen for serum pentobarbital quantitation.
• Adaptation of urine fluorescence polarization immunoassay (FPI) screen for serum pentobarbital analysis.
• Comparison of immunoassay results with HPLC using regression and multiple linear regression analyses.

Main Results:

• Adapted EMIT and FPI methods demonstrated high precision (less than 6% between-day variability).
• Excellent agreement was observed between immunoassay methods and HPLC (r = 0.97).
• Multiple regression analysis confirmed concordance among all tested immunoassay techniques.

Conclusions:

• Adapted immunoassays provide a reliable and accurate approach for quantifying serum pentobarbital.
• These methods offer a viable alternative to HPLC for therapeutic drug monitoring in Reye's syndrome.
• Immunoassay techniques are suitable for routine clinical laboratory analysis of serum pentobarbital.