Sensitive and simple determination of mannitol in human brain tissues by gas chromatography–mass spectrometry

• Published in: Journal of chromatography. B, Biomedical sciences and applications Biomedical sciences and applications, 2001-07, Vol.758 (1), p.103-108
• Main Authors: Kiyoshima, Akiko, Kudo, Keiko, Hino, Yukiko, Ikeda, Noriaki
• Format: Article
• Language: English
• Subjects: Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Autopsy; Biological and medical sciences; Brain Chemistry; Calibration; Clinical death. Palliative care. Organ gift and preservation; Gas Chromatography-Mass Spectrometry - methods; Humans; Investigative techniques, diagnostic techniques (general aspects); Mannitol; Mannitol - analysis; Medical sciences; Nervous system; Pathology. Cytology. Biochemistry. Spectrometry. Miscellaneous investigative techniques; Reference Standards; Sensitivity and Specificity
• ISSN: 0378-4347; 1387-2273
• DOI: 10.1016/S0378-4347(01)00145-1

A simple, reliable and sensitive gas chromatographic–mass spectrometric method was devised to determine the level of mannitol in various human brain tissues obtained at autopsy. Mannitol was extracted with 10% trichloroacetic acid solution which effectively precipitated brain tissues. The supernatant was washed with tert.-butyl methyl ether to remove other organic compounds and to neutralize the aqueous solution. Mannitol was then derivatized with 1-butaneboronic acid and subjected to GC–MS. Erythritol was used as an internal standard. For quantitation, selected ion monitoring with m/ z 127 and 253 for mannitol and m/ z 127 for internal standard were used. Calibration curves were linear in concentration range from 0.2 to 20 μg/0.1 g and correlation coefficients exceeded 0.99. The lower detection limit of mannitol in distilled water was 1 ng/0.1 g. Mannitol was detected in control brain tissues, as a biological compound, at a level of 50 ng/0.1 g. The precision of this method was examined with use of two different concentrations, 2 and 20 μg/0.1 g, and the relative standard deviation ranged from 0.8 to 8.3%. We used this method to determine mannitol in brain tissues from an autopsied individual who had been clinically diagnosed as being brain dead. Cardiac arrest occurred 4 days later.