3-Methoxy-4-Hydroxymandelic Acid (VMA) by Microfiber Chromatography

[摘要] A method is presented for the rapid, precise, quantitative measurement of 3-methoxy-4-hydroxymandelic acid (VMA) in urine. The method is unique in that it utilizes silica-gel-impregnated glass fiber as a support medium for thin-layer chromatography. An ethyl acetate extract of acidified urine was spotted and chromatographed in an ascending technic using tolulene, glacial acetic acid, and ethyl acetate (70:20:5) as a solvent system. The VMA is identified by spraying the chromatogram with diazotized p-nitroanaline. Semiquantitation was made with accuracy by visual inspection and comparison with simultaneously spotted standards. Precise quantitation was made by strip scanning. Diet and a variety of medication did not interfere. The normal range was found to be 0-4 mg./L.

[学科分类] 过敏症与临床免疫学