IJLST 2018 Volume 11 Issue 2

Title:

A Forensic view: Quality Control Norms for Analytical Instruments

Authors

Nilimamayee Samal, A.C. Rajvanshi

Lok Nayak Jayaprakash Narayan National Institute of Criminology and Forensic Science, New Delhi, INDIA

nilima.samal1@gmail.com, aviraj29@gmail.com

ABSTRACT:

A wide variety of Analytical Instruments are available for identification and quantification of various drugs and poisons in Forensic Toxicology Laboratories. The LC-MS/MS (Liquid Chromatography- Mass Spectrometer with tandem Mass) is an emerging technique in the field of Forensic Toxicology, which provides the ability to analyze a high range molecular weight; high polarity range of compounds with high sensitivity and specificity, in less time. But in case of LC-MS or LC-MS/MS, many factors influence the mass spectra of organic molecule during analysis. The collision induced dissociation of organic molecules by Atmospheric Pressure Chemical Ionization (APCI) or Electro-Spray Ionization (ESI) show the need of standardization of experimental conditions for building up a reference library. The different mass filters like Time of Flight (TOF), Ion Trap, Single or Triple Quadruple, Magnetic Sector Mass Analyzers in single or multiple mass spectrometry coupled with High Performance Liquid Chromatography(HPLC) give their unique pattern of mass spectra which are not easy to compare with each other. So, when confirmation of identity of a compound is required, it is very difficult to rely on the definite set of library data. In this article, the attention on the above problem is directed explicitly to Forensic Toxicology. The standard protocol that should be followed and the number of Identification Points or Information Points (IPs) that should be taken into account for confirmation of identity of a chemical compound by LC-MS/MS has been discussed.

Keywords: Analytical Instrumentation, LC-MS/MS, Quality Criteria, Identification Point, Forensic Toxicology.