Rapid and sensitive analysis of morphine in serum by reversed-phase high performance liquid chromatography with...

A method is described for the determination of morphine in serum. Separation and quantitation are performed by reversed-phase high performance liquid chromatography with electrochemical detection. A sample size of 100 microL or less is required for detection of concentrations as low as 1 to 2 ng/mL. In trials with standard solutions, recovery was 75%. The between-run and within-run coefficients of variation were 7.3% (over the range of 5 to 200 ng/mL) and 9.1% (at 5 ng/mL), respectively.