DIRECT ANALYSIS OF FILTER-PAPER BLOOD SPECIMENS FOR IDENTIFICATION OFSMITH-LEMLI-OPITZ SYNDROME USING TIME-OF-FLIGHT SECONDARY-ION MASS-SPECTROMETRY

In this study, time-of-flight secondary ion mass spectrometry was used to distinguish between blood of normal infants and that of individual s with Smith-Lemli-Opitz (SLO) syndrome. SLO syndrome results in an ab normally low concentration of blood cholesterol and an elevated concen tration of 7-dehydrocholesterol. Blood was spotted on filter paper and analyzed directly with no extractions or separations. Results showed that using ratios of fragment ions for cholesterol/dehydrocholesterol, patients with SLO and normal individuals could be unambiguously disti nguished. Unknown samples from 28 individuals were obtained and identi fied correctly. (C) 1997 Wiley-Liss, Inc.