High-performance liquid chromatographic analysis of p-nitrophenol and its conjugates in biological samples.
p-Nitrophenol (pNP) and its conjugated metabolites, generated in a perfused rat liver preparation, are readily separated and quantitated in serum perfusate and bile samples using a reverse-phase high-performance liquid chromatographic method. Serum perfusate samples can be analyzed following protein precipitation with acetonitrile: following protein precipitation with 1.5 M perchloric acid (1 part to 2 parts serum) there was degradation of pNP sulfate to pNP when samples were stored at room temperature. pNP can also be analyzed in blood perfusate samples following extraction with a number of organic solvents including ethyl acetate or isobutanol-methylene chloride (4:1, v/v). Rat liver perfusions at a constant input concentration of 40 microM demonstrated a high hepatic extraction ratio of pNP (mean of 0.90) due to the formation of the sulfate and glucuronide conjugates; no pNP glucoside was detected in perfusate or bile samples.
Morris
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ME
Department of Pharmaceutics, School of Pharmacy, State University of New York, Buffalo 14260.
Hansel
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SB
D000818:Animals; D001646:Bile / Q000737:chemistry; D000440:Butanols; D002851:Chromatography, High Pressure Liquid; D005965:Glucuronates / Q000032:analysis* / Q000378:metabolism; D008099:Liver / Q000378:metabolism*; D008297:Male; D008752:Methylene Chloride; D009578:Nitrobenzenes / Q000032:analysis* / Q000378:metabolism; D009596:Nitrophenols / Q000032:analysis* / Q000097:blood / Q000378:metabolism; D010477:Perfusion; D051381:Rats; D011919:Rats, Inbred Strains; D012997:Solvents
D000440:Butanols; D005965:Glucuronates; D009578:Nitrobenzenes; D009596:Nitrophenols; D012997:Solvents; C002730:4-nitrophenylglucuronide; C023379:4-nitrophenyl sulfate; C040507:isobutyl alcohol; D008752:Methylene Chloride; C024836:4-nitrophenol