Reversed-phase high-performance liquid chromatographic approach to determine total lymphocyte concentrations of 6-thioguanine, methylmercaptopurine and methylthioguanine in humans.
A reversed-phase high-performance liquid chromatographic (HPLC) procedure was developed to quantify intracellular lymphocyte 6-thioguanine, methylmercaptopurine and methylthioguanine. The free base of each metabolite was obtained by acid hydrolysis, which allowed for a total determination of thiopurine metabolites. 6-Thioguanine was analyzed on an octadecylsilane column using acetonitrile-10 mM sodium phosphate (11:89), pH 7, containing 0.06% tetrabutylammonium chloride. 6-Thioguanine was oxidized with potassium permanganate, and fluorescence was measured at 330 nm excitation and 410 nm emission. Methylmercaptopurine and methylthioguanine were separated on a cyanopropylsilane column using methanol-40 mM sodium phosphate (22:78), pH 2.7, and detected by ultraviolet absorbance at 314 and 290 nm, respectively.
Erdmann
G R
GR
Department of Pharmacy Practice, College of Pharmacy, University of Minnesota, Minneapolis 55455.
Steury
J C
JC
Carleton
B C
BC
Stafford
R J
RJ
Bostrom
B C
BC
Canafax
D M
DM
D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005453:Fluorescence; D006801:Humans; D008214:Lymphocytes / Q000737:chemistry*; D015122:Mercaptopurine / Q000031:analogs & derivatives* / Q000097:blood; D013866:Thioguanine / Q000031:analogs & derivatives* / Q000097:blood*
C035366:6-methylthioguanine; C010240:6-methylthiopurine; D015122:Mercaptopurine; D013866:Thioguanine