Application of high-performance liquid chromatography/mass spectrometry to drug screening

State-of-the-art of bone marrow analysis in forensic toxicology: a review

Although blood is the reference medium in the field of forensic toxicology, alternative matrices are required in case of limited, unavailable or unusable blood samples. The present review investigated the suitability of bone marrow (BM) as an alternative matrix to characterize xenobiotic consumption and its influence on the occurrence of death. Basic data on BM physiology are reported in order to highlight the specificities of this matrix and their analytical and toxicokinetic consequences. A review of case reports, animal and human studies involving BM sample analysis focuses on the various parameters of interpretation of toxicological results: analytic limits, sampling location, pharmacokinetics, blood/BM concentration correlation, stability and postmortem redistribution. Tables summarizing the analytical conditions and quantification of 45 compounds from BM samples provide a useful tool for toxicologists. A specific section devoted to ethanol shows that, despite successful quantification, interpretation is highly dependent on postmortem interval. In conclusion, BM is an interesting alternative matrix, and further experimental data and validated assays are required to confirm its great potential relevance in forensic toxicology.

Method for Screening and Quantitative Determination of Serum Levels of Salicylic Acid, Acetaminophen, Theophylline, Phenobarbital, Bromvalerylurea, Pentobarbital, and Amobarbital Using Liquid Chromatography/Electrospray Mass Spectrometry

We investigated a method for the simultaneous screening, identification, and quantitative determination of salicylic acid, acetaminophen, theophylline, barbiturates, and bromvalerylurea, drugs that frequently cause acute poisoning in Japan and therefore require rapid analysis for effective treatment in the clinical setting. The method employs liquid chromatography/electrospray mass spectrometry (LC/MS) of solid-phase extracted serum samples. For LC/MS ionization, the electrospray-ionization method was used, with acetaminophen in the positive-ion mode, and salicylic acid, theophylline, phenobarbital, bromvalerylurea, pentobarbital, amobarbital, and o-acetamidophenol (internal standard) in the negative-ion mode, the base ions were used in each case for quantitative analysis. Quantitation was possible for the following sample concentration ranges: salicylic acid and acetaminophen, 100 to 5 microg/ml; theophylline, 100 to 0.5 microg/ml; and phenobarbital, bromvalerylurea, pentobarbital, and amobarbital, 100 to 1 microg/ml. Using full-scan mass spectrometry, the lower detection limits of 1 microg/ml for salicylic acid and acetaminophen, 0.1 microg/ml for theophylline, and 0.5 microg/ml for phenobarbital, bromvalerylurea, pentobarbital, and amobarbital were adequate for identifying acute poisoning. When each compound was added to serum to a final concentration of 5 microg/ml and solid-phase extraction was performed using Oasis HLB 1-cc (30-mg), the mean recovery rate of each compound was 89.2 to 96.1% (n=5), and the coefficients of variation of the intraday and interday assays were 3.55 to 6.05% (n=5) and 3.68 to 6.38% (n=5), respectively, which are acceptable. When this method of analysis was applied in testing the sera of a female patient who had consumed a large amount of an unknown commercial drug, salicylic acid and bromvalerylurea were identified, and the treatment strategy could be determined in accordance with the serum concentration of those drugs.

Simultaneous determination of bromvalerylurea and allylisopropylacetylurea in human blood and urine by gas chromatography-mass spectrometry

We devised a sensitive and simple method to simultaneously determine bromvalerylurea and allylisopropylacetylurea in human blood and urine by gas chromatography-mass spectrometry. Bromvalerylurea and allylisopropylacetylurea were extracted using an Extrelut column with an internal standard, 2-bromohexanoylurea, followed by derivatization with heptafluorobutyric anhydride. The derivatized extract was submitted to GC-MS analysis of EI-SIM mode. The calibration curves of both compounds were linear in the concentration range from 0.01 to 10 microg/ml in both blood and urine samples. The lower limits of detection of bromvalerylurea and allylisopropylacetylurea were 0.005 and 0.005 microg/ml, respectively. This method proved most useful in accurately identifying these drugs in blood and urine from an autopsied individual.

Hyphenated liquid chromatographic techniques in forensic toxicology

The prerequisite of applicability of hyphenated methods in forensic analysis is the achievement of a stage of "final maturity". In the field of liquid chromatography, HPLC coupled with diode array detection (DAD) seems to fulfill this criterion, whilst the combination with atmospheric pressure ionization mass spectrometry (HPLC-API-MS) is still in a development stage. HPLC-DAD is broadly used as identification tool in forensic and in emergency toxicology. Two main approaches were observed; development of retention index scales for intra-laboratory exchange of data and establishing of databases only for intra-laboratory use. Using these approaches, several databases were established for toxicological relevant substances (illicit and therapeutic drugs and their metabolites, environmental poisons etc.) in biological fluids. Also, complete HPLC-DAD identification systems are commercially available. Further possibility of progress depends on the on-line combination ("triple hyphenation") with other detection methods, preferably API-MS. HPLC-API-MS, both in electrospray (ESI) and atmospheric pressure chemical ionization (APCI) options, underwent dramatic development in the last decade and is reaching its final shape. The method was broadly applied for various groups of toxicologically relevant substances, a lot of them unaccessible for other techniques, including GC-MS. Particularly important was application of HPLC-API-MS for detection and quantitation of active, polar metabolites of various drugs and for analysis of macromolecules. APCI seems to be more useful for analysis of less polar compounds, whereas ESI is particularly valuable for determination of polar, large molecules (e.g., toxic peptides, polar metabolites etc.) Up to now, HPLC-API-MS has been mainly applied for dedicated analyses, but the introduction of APCI or ESI in systematic toxicological screening may be expected in the near future.