Analysis of supplemented vitamin K1(20) in serum microsamples by solid-phase extraction and narrow-bone HPLC with multichannel ultraviolet detection.
A sensitive method for the determination of vitamin K1(20) in serum microsamples (50 microL) has been developed, utilizing solid-phase extraction with C8 Bond-Elut columns and reversed-phase narrow-bore high-performance liquid chromatography [2.1 mm (i.d.), column] with a nonaqueous eluent. Recovery from serum (49 ng/mL) was 76% (n = 2). Peak homogeneity was assessed by photodiode array detection with absorbance ratio, spectral normalization, and transformation to the first- and second-derivative chromatograms. Calibration data at 248 nm over two ranges (20-200 ng/mL, 200-4000 ng/mL) varied linearly with concentration and were suitable for studies of vitamin K1 supplementation. By comparison with conventional columns, sensitivity was increased twofold.
Kirk
E M
EM
Pharmaceutical Chemistry, School of Pharmacy, University of Bradford, U.K.
Fell
A F
AF
D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation; D006801:Humans; D008832:Microchemistry; D012997:Solvents; D013056:Spectrophotometry, Ultraviolet; D014812:Vitamin K / Q000008:administration & dosage / Q000097:blood*
D012997:Solvents; D014812:Vitamin K