Magnetic circular dichroism spectroscopy: Convenient quantitative determination of uroporphyrin and coproporphyrin in urine samples

✍ Scribed by Günter Barth; Ruth Records; Robert E. Linder; Edward Bunnenberg; Carl Djerassi

• Book ID: 102984053
• Publisher: Elsevier Science
• Year: 1977
• Tongue: English
• Weight: 574 KB
• Volume: 80
• Category: Article
• ISSN: 0003-2697
• DOI: 10.1016/0003-2697(77)90621-2

✦ Synopsis

Magnetic circular dichroism provides a convenient, sensitive, and accurate method to determine the concentration of uroporphyrin (I) and coproporphyrin (II) in urine specimens. The acidified sample is measured directly, and the recorded spectrum is analyzed by a least-squares fitting procedure using the spectra of the pure components as fitting functions. The lowest detection limit is 10 &liter of total porphyrins, the accuracy is about 5%, and the minimum sample volume required is 1 ml. The possibility of determining small amounts of myoglobin in serum was also investigated. Conversion to the hemochrome results in the occurrence of a very intense MCD band at 555 nm, thus permitting the detection of myoglobin levels as low as 0.1-0.2 pglml.