Long-term performance of a gas chromatography/tandem mass spectrometry assay for tebufelone in plasma

Abstract

An automated gas chromatography/tandem mass spectrometry (GC/MS/MS) based method for the rapid determination of tebufelone (TE) in animal and human plasma has been routinely applied in our laboratory to more than 3000 samples over a 2-year period. The selectivity of MS/MS conducted on a triple quadrupole instrument, combined with the use of a stable-isotope-labeled internal standard, results in excellent analytical figures of merit, as well as minimal sample preparation, rapid analysis, and high assay reliability. The work described here goes beyond initial method development and validation studies by evaluating the long-term performance of quantitative GC/MS/MS. Electron ionization produces M.+ ions for TE and the [13C, 18O]TE internal standard, which are selected in Q1 and undergo collisionally activated dissociation in Q2. Quantitation is based on monitoring daughter ions at m/z 248 and 251, respectively, in Q3. A linear range of 1-3000 ng of TE/sample (20 pg to 60 ng injected) provides access to an effective concentration range of 0.5-30,000 ppb TE in plasma (0.1-2-g samples). The assay shows no bias and less than 10% relative standard deviation over this range. In the automated mode, less than 7 min elapse from injection to report printout and more than 70 plasma samples are routinely prepared and analyzed in a day. Such performance is consistently maintained throughout long-term application.

Quantitative analysis of crude plasma extracts by ion trap tandem mass spectrometry

“…Human plasma and clinical samples (HIV negative) were obtained within Miami Valley Laboratories and were handled with universal precautions. The extraction procedure was previously validated for a clinical assay based on triple quadrupole MS/MS, which has been fully discussed by Dobson et al [13). To obtain a calibration line from plasma, 1-g samples were spiked with 10 ILL aliquots of TE and the internal standard, as described above (n = 3).…”

Hyphenated chromatographic methods for biomaterials

“…In the SIM mode, a quantification limit of 600 fmol per injection could be achieved for the three compounds. An automated GC-tandem MS for determining tebufelone (TE), an anti-inflammatory candidate, and its 13 C, 18 O labeled (TE-CO) analog was developed by Dobson et al (1994). The stable-isotope-labeled TE was used as an in vivo IS to determine the oral administration absolute bioavailability.…”

“…Tandem (ie multi-stage) MS is a frequently used technique for identification, structural elucidation of an unknown and to improve the selectivity of quantitative analyses (De Jong et al, 1989;Dobson et al, 1994;Kemp et al, 1995;Schweer et al, 1996). The majority of tandem MS is performed with triple quadropole where the first acts as a mass selective filter for the parent ion which is then further fragmented by a collision gas such as argon in the second quadropole.…”

Quantitative determination of endocrine- disrupting polychlorinated biphenyls and organochlorinated pesticides in human serum using gas chromatography with electron-capture detection and tandem mass spectrometry

“…Determination was carried by capillary GC/ECD and GC/MS/MS. Both chromatographic methods were developed taking into account the criteria established for the validation of routine quantitative analytical compounds 26–28. The limitations and advantages of using GC/ECD or GC/MS/MS techniques for quantitative and qualitative analyses of serum samples are compared and discussed.…”