A routine method for cholesterol and 7-dehydrocholesterol analysis in dried blood spot by GC-FID to diagnose the Smith-Lemli-Opitz syndrome

Monica Gelzo, Stefano Clericuzio, Rosalba Barone, Oceania D'Apolito, Antonio Dello Russo, Gaetano Corso

Research output: Contribution to journalArticle


This work was aimed to implement a fast and simple method to quantify cholesterol (CHOL) and 7-dehydrocholesterol (7-DHC) in dried blood spot (DBS) to diagnose the Smith-Lemli-Opitz syndrome (SLOS), an inborn error of CHOL biosynthesis. We developed and validated a GC-FID method for separation and quantification of underivatized CHOL and 7-DHC using a DBS disc of 6 mm with a run time of 9. min. Correlation coefficients (r) of calibration curves ranged from 0.998 to 0.999 for CHOL and from 0.997 to 0.998 for 7-DHC. Within-day and between-day imprecision (CV%), accuracy (%), carry-over, and extraction efficacy (%) were also evaluated for validation. CHOL and 7-DHC were analyzed in DBS and plasma samples from 8 SLOS patients and 30 unaffected subjects. In SLOS patients, 7-DHC/CHOL ratios in DBS and plasma samples ranged from 0.035 to 1.448 and from 0.012 to 0.926, respectively. Results from calibration curves, quality controls and patient samples reveal that the method is suitable to analyze DBS to screen patients affected by SLOS.

Original languageEnglish
Pages (from-to)154-158
Number of pages5
JournalJournal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences
Publication statusPublished - Oct 15 2012



  • DBS
  • GC-FID
  • SLOS

ASJC Scopus subject areas

  • Biochemistry
  • Analytical Chemistry
  • Cell Biology
  • Clinical Biochemistry

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