Forensic Science Laboratory Research Articles

A rapid and cost-effective method based on dispersive liquid-liquid microextraction coupled to injection port silylation-gas chromatography-mass spectrometry for determination of morphine in illicit opium.

A simple, rapid, cost-effective and environment friendly analytical method based on dispersive liquid-liquid microextraction (DLLME) coupled to injection port silylation (IPS)-gas chromatography-mass spectrometry is described for the determination of morphine in illicit opium samples. Raw opium was dispersed in ultrapure water and 5mL of aqueous sample was subjected to DLLME by rapidly injecting a mixture of chloroform and acetone (extraction and disperser solvent, respectively) followed by ultrasonication for 1min and subsequent centrifugation for 3min at 5000rpm. The sedimented phase thus obtained was reconstituted in acetonitrile and 1 µL along with 1 µL of N,O-Bis(trimethylsilyl)acetamide (BSA) was injected manually into GC-MS injection port at a temperature of 250°C. The derivatization reaction was completed instantaneously inside the heated GC-MS injection port without any side product. Various parameters associated with IPS and DLLME have been thoroughly optimized. Under the optimized conditions, the method has been found linear in the range of 5-50µg/mL with a correlation coefficient (R 2) of 0.997. The limit of detection (LOD) and limit of quantification (LOQ) for morphine-diTMS were found to be 1.6 and 4.8µg/mL. The method has been successfully applied for the quantitative analysis of morphine in illicit opium samples. In conclusion, the proposed method has completely eliminated the time consuming and laborious steps of LLE and in-vial silylation and can be routinely used for analysis of opium and other polar analytes in forensic science laboratories.

Screening/Spot/Colour test of hallucinogens

Hallucinogens are diverse group of chemicals occurring naturally as well as synthetic. These drugs produce bizarre effects on the mind, such as distortion of time, space, sound, colour, and other sensations. It acts primarily on the central nervous system and interfere with the filtering mechanisms of the mind causing alterations in perceptions, thinking and moods. In India, Forensic Science Laboratories run by Government under the Home ministry usually carry out this. The samples must be analyzed by the forensic toxicologist/chemists/scientist. This article deals with the screening/spot test for hallucinogens. It attempts has been made for screening/spot/colour test of Hallucinogens in a stepwise manner, which can be of handy reference for the forensic toxicologist/scientist/chemist.

Chloroplast gene markers detect diatom DNA in a drowned mice establishing drowning as a cause of death.

Diatoms are unicellular microalgae with cell wall made up of rigid silica found in all open water bodies. They thus resist degradation and hence are important tool to diagnose cause of death in drowned bodies. The nitric acid digestion method practiced conventionally in forensic science laboratories has limitations due to manual error. Plant chloroplast genes found in diatoms such as ribulose-1,5-bisphosphate carboxylase oxygenase (rbcL-3P) and rbcL, universal plastidic amplicon (UPA), and photosynthesis I P700 apoprotein chlorophyll Al (psaA), which play an important role in photosystems I and II of photosynthesis, are tested to diagnose drowning in experimental mice. It was seen that psaA-2 showed amplification at 150bp in all biological samples. The sequences of psaA-2 gene marker showed 100% proximity to Thalassiosira weissflogii and rbcL-3P showed 99% resemblance to Pseudo-nitzschia multiseries. On the other hand, in postmortem drowned biological samples, the chloroplast-based gene marker failed to show any amplification.

Structure Analysis and Characterization of Aminorex Analogue 4'-F-4-MAR

Objective To study the identification method for 4'-F-4-methylaminorex （4'-F-4-MAR） in samples without reference substance. Methods Gas chromatography-mass spectrometry （GC-MS）, ultra-high-performance liquid chromatography-quadrupole time-of-flight-mass spectrometry （UPLC-QTOF-MS）, nuclear magnetic resonance （NMR） and Fourier transform infrared （FTIR） were comprehensively used for the structure identification of 4'-F-4-MAR in samples. Results Under the positive electrospray ionization （ESI+） mode, quasi-molecular ion in the first order mass spectrometry of the unknown compound was 195.092 6 and its molecular formula was inferred to be C10H11FN2O. The fragment ions in the mass spectrometry of the unknown compound were compared with the related fragment ions of 4,4'-dimethylaminorex （4,4'-DMAR） in literature. It was found that the main fragment ions of the unknown compound were all 4 bigger than the corresponding fragment ions of 4,4'-DMAR. Therefore, the unknown compound was inferred to be a 4,4'-DMAR analogue with a methyl substituted by a fluorine in the benzene ring. The equivalent protons at δ=7.30 and δ=7.06 in 1H-nuclear magnetic resonance （1H-NMR） spectra and the characteristic spin-spin coupling constants （1JC-F=245.2 Hz, 2JC-F=21.3 Hz, 3JC-F=8.1 Hz） for 13C-19F interactions in carbon spectra, further proved that the fluorine substituted methyl at the para-position of the benzene ring. Finally, the unknown compound was determined as 4'-F-4-MAR. Conclusion A method that comprehensively used the identification materials 4'-F-4-MAR in GC-MS, UPLC-QTOF-MS, NMR and FTIR is established and the fragmentation mechanism of fragmentation ions of 4'-F-4-MAR created under the two modes -- electron impact （EI） and electrospray ionization under collision induced dissociation （ESI-CID） is deduced. The information will assist forensic science laboratories in identifying this compound or other substances with similar structure in their case work.

Importance of Ultra-pure Water for Sample Collection in Vitriolage Cases - Forensic Concern for Corrosives Examination

itriolage, a heinous crime committed with intention to disfigure a person has come into view as an extremely brutal gender-based crime especially against young women in India and also another part of world mainly in South Asia over the past few years. India is facing an alarming situation of crime against women such as rape, domestic violence, dowry deaths etc. In recent year’s cases of vitriolage are on the rise in India. By understanding the gravity of crime, section 326A and 326B was incorporated in the prevailing Indian Penal Code and came into effect from 3 February 2013. Forensic Science Laboratory, Delhi receives a number of cases pertaining to acid attacks every year. We present here five such cases which were received for forensic examination. The exhibits were analyzed using Ion Chromatography apart from classical tests in order to strengthen the forensic reports and play vital role in conviction of the accused. This paper encompasses the necessity and importance of controlled samples treated with the quality of water used in analysis, importance of packing of exhibits and role of investigating agencies/police in collection of exhibits, which play crucial role in proving the sanctity of the forensic examination.

Digital transformation risk management in forensic science laboratories

Technological advances are changing how forensic laboratories operate in all forensic disciplines, not only digital. Computers support workflow management, enable evidence analysis (physical and digital), and new technology enables previously unavailable forensic capabilities. Used properly, the integration of digital systems supports greater efficiency and reproducibility, and drives digital transformation of forensic laboratories. However, without the necessary preparations, these digital transformations can undermine the core principles and processes of forensic laboratories. Pertinent examples of problems involving technology that have occurred in laboratories are provided, along with opportunities and risk mitigation strategies, based on the authors’ experiences. Forensic preparedness concentrating on digital data reduces the cost and operational disruption of responding to various kinds of problems, including misplaced exhibits, allegations of employee misconduct, disclosure requirements, and information security breaches. This work presents recommendations to help forensic laboratories prepare for and manage these risks, to use technology effectively, and ultimately strengthen forensic science. The importance of involving digital forensic expertise in risk management of digital transformations in laboratories is emphasized. Forensic laboratories that do not adopt forensic digital preparedness will produce results based on digital data and processes that cannot be verified independently, leaving them vulnerable to challenge. The recommendations in this work could enhance international standards such as ISO/IEC 17025 used to assess and accredit laboratories.

Nano-interface driven electrochemical sensor for pesticides detection based on the acetylcholinesterase enzyme inhibition

Forensic Science Laboratories usually receive numerous cases of suicidal, accidental, and homicidal poisoning most often involving organophosphorus (OP) pesticides. The toxicity of the OP pesticides arises due to their ability to inhibit the activity of acetylcholinesterase (AChE), a cholinergic enzyme that is essential for the proper functioning of the central nervous system. Conventional techniques which are currently in use for pesticide detection are time-consuming, need upskilled technicians as well as suffer from low sensitivity. Therefore, the more rapid and sensitive electrochemical biosensors based on the principle of AChE enzyme inhibition have emerged out to be a simple and promising alternative to the conventional techniques. Since, most of the time, the poison isolated from biological material in poisoning cases is in nM quantities, an attempt has been made for the development of biosensor with enhanced sensitivity in the nM range using reduced graphene oxide (rGO) and zinc oxide nanoflowers (ZnONFs). The rGO and ZnONFs were synthesized chemically and deposited electrochemically on the Au electrode. AChE was immobilized onto this prepared nano-interface (ZnONFs/rGO/Au) through chitosan and glutaraldehyde cross-linking. The fabricated sensor was characterized step by step with cyclic voltammogram and electrochemical impedance spectroscopy. This advanced nanomaterials based techniques has been explored for detecting pesticides in visceral samples. The limit of detection (LOD) for the present sensor was 0.01 nM for OP pesticides.

Validation of an analytical method for the detection of ephedrine and its analogues in forensic samples using HPTLC–MS

Drug abuse is a global menace in the society. Strict measures are planned and effectuated to dismantle this crime yet a large number of cases of narcotics drugs are seized and referred to forensic science laboratories for analysis. Over the past few years, the misuse of precursor chemicals has increased substantially. Examination of these precursor chemicals, especially ephedrine and its analogues, is a major task for forensic analysts. Though gas chromatography–mass spectrometry (GC–MS) is a well-established technique, it dwindles in the identification of the analogues of ephedrine as they have similarity in molecular weight and structure. The analysis involves time-consuming extraction and derivatization process in sample preparation when used for the identification of isomers. The present paper describes a use of high-performance thin-layer chromatography coupled with mass spectrometry (HPTLC–MS) for the purpose. This technique requires minimum sample preparation; it is a quick and easy methodology with no derivatization and gives a conclusive result for the separation and identification of ephedrine analogues. The drug samples were dissolved in methanol and spotted on Si60 F254 thin-layer chromatography (TLC) plate. Good separation of ephedrine from a mixture of ephedrine, pseudoephedrine, and phenylpropanolamine was achieved using the solvent system n-butyl acetate–acetone–n-butanol–5 M ammonia–methanol (4:2:2:1:1, v/v). The separated spot on the TLC was subjected to MS, which identified ephedrine with confirmation.

New Trends of Substance Abuse During COVID-19 Pandemic: An International Perspective.

In the late 2019, an epidemic of cases with severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) has spread from China to the rest of the world, resulting in a global pandemic (COronaVIrus Disease 19, COVID-19 pandemic). Starting from the first months of 2020, several restrictions have been imposed by governments to face the public health threat, impacting the usual patterns of drug abuse throughout the world (1). The temporary border closure affected the usual illicit drug route of shipping from country to country, resulting in scarcity of classic street drugs (2). Moreover, restrictive measures internationally adopted by several countries made necessary to close all the usual recreational settings in which stimulants drugs are commonly abused. On the contrary, since in house drugs abuse became the most feasible option, other private encounters might have caught on, such as chemsex (3). In particular this phenomenon, which originated mainly in the large cities of Northern Europe, has gradually spread across the continent and is now a worrying reality in western European countries. Other rising trends of substance abuse include cognitive enhancers and new psychoactive substances (4, 5). Furthermore, the consequent social isolation and the likely limited access to detoxification centers caused additional psychological distress, pushing drug addicts toward alternative psychotropic drugs, possibly through illegal online marketplaces. An international overview of the new trends of drug abuse during the current COVID-19 pandemic and the related health risks are hereby discussed, taking into consideration different points of view. Can New Trends of Substance Abuse Be Identified During COVID-19 Pandemic? As we write this opinion paper, the social and economic restrictions due to the coronavirus pandemic have already seriously impacted health and social fields. COVID-19 outbreak has led to the implementation of social distancing to contain the spread of the disease, changing people’s lifestyle. People have been going through a moment of anxiety and fear for their health and their jobs, and they are forced to live an unfamiliar lifestyle, deprived of relationships. Furthermore, the condition of people with psychological troubles may have worsened during the pandemic as a result of the unconsciously mirroring of others feelings (6). This peculiar situation may have pushed more people toward a deviant behavior linked to licit or illicit substance use, and it may have been a good opportunity for drug dealers to attract new customers. However, global issues have not favored the usual trade business. Indeed, social distancing has substantially reduced drug trafficking on the streets, pushing consumers toward illegal markets on the dark web or through messaging applications (7). Furthermore, the paucity of classic drugs, together with the impossibility to go out to look for those, might have induced addicts to misuse psychoactive prescription drugs such as benzodiazepines (8–10). In this concern, although there is limited scientific evidence, the impact of the COVID-19 pandemic could lead to substantial modifications in substance use patterns, and an increased risk of substitution, adulteration, contamination, and dilution with a potentially harmful substance. As such, reports from forensic science and toxicology laboratories are crucial for the early detection and response to such events (11, 12). Moreover, in this period of home confinement, users might no longer be looking for “socializing” substances to be used in recreational settings, but for psychotropic drugs to be consumed in solitude. Even short periods of isolation and loneliness can have negative consequences on physical and mental well-being. The feeling of isolation can lead to anxiety and anger, and even sleep disorders, depression, and post-traumatic stress disorders, which may be underestimated due to the lack of specific screening tools (13, 14). Moreover, psychiatric assistance from health professionals is not assured due to the temporary monopolization of psychiatric facilities for COVID-19 treatment (15). In addition to drug addicts using prescription sedatives available at home, some may have shifted to narcotics such as new synthetic opioids or designer benzodiazepines, available online. Indeed, these two classes of new psychoactive substances showed the highest consumption increase in 2019 (16–19).

Histochemistry based confirmation of the diagnosis of Copper Sulphate Poisoning: Case-Series

The suspected suicidal death cases from copper sulphate poisoning is not uncommon in West Bengal as well as in some other parts of India. But due to extreme delay in laboratory confirmation report from Forensic Science Laboratory (FSL) regarding presence of copper in toxic doses in the preserved samples the final opinion regarding cause of death in medico legal autopsy cases is kept pending. The histochemical method of rubeonic (rubeanic) acid staining of hepatocytes to determine the presence of copper in toxic level there, can be used as an alternative method to confirm copper sulphate poisoning. In this study, slides of liver biopsy from twelve autopsy cases of suspected copper sulphate poisoning are stained with rubeonic acid. All of them showed positive results indicating confirmation of copper sulphate poisoning. Hence, this method can be adopted as an alternative to toxicological analysis of copper sulphate poisoning.

The Psilocin (4-hydroxy-N,N-dimethyltryptamine) and Bufotenine (5-hydroxy-N,N-dimethyltryptamine) Case: Ensuring the Correct Isomer has Been Identified.

Psilocin (4-hydroxy-N,N-dimethyltryptamine, 4-HO-DMT) and bufotenine (5-hydroxy-N,N-dimethyltryptamine, 5-HO-DMT), which are both naturally occurring compounds, are classified as controlled substances in numerous countries due to their pharmacological activities and recreational usage. There are two other benzene ring regioisomers, 6-hydroxy-N,N-dimethyltryptamine (6-HO-DMT) and 7-hydroxy-N,N-dimethyltryptamine (7-HO-DMT), which are not classified by name as controlled substances, and which were synthesized for this current work. The four isomers were analyzed using routine methodologies employed by the Israel's Police Division of Identification and Forensic Science (DIFS) Laboratory, namely thin layer chromatography (TLC), Fourier transform infrared spectroscopy (FTIR), and gas chromatography mass spectroscopy (GC-MS). It was found possible to differentiate the four isomers. Forensic specimens that were suspected to be psilocybe mushrooms were examined, confirming that it is now possible to unequivocally identify the presence of psilocin and rule out the presence of its other isomers.

Profile of Deaths Due to Poisoning: Autopsied at Ssims & Rc - A Cross Sectional Study

Poisoning is an important health problem in every country of the world and it is a known fact that the incidence of poisoning in India is highest and it is estimated that more than 50,000 people die every year from poisoning1. Poisoning affects all age groups from infants to seniors, but poisoning in teens and adults are more serious and it contributes to morbidity and mortality. Due to easy accessibility of poisons and lack of awareness, self-poisoning deaths are more common. In most of the poisoning deaths, the poison consumed was unknown at the time of autopsy but Forensic Science Laboratory plays a vital role in detection of poison. With this background, the present study has been carried out to determine the profile of poisoning cases, autopsied at SSIMS&RC, DAVANGERE, KARNATAKA. The study revealed that more number of poisoning is seen in males (62.3%) as compare to females (37.7%). Common age group affected is 21 to 30 years, followed by 31 to 40 years and least in 41 to 50 years. Agriculture group is commonly affected, followed by unemployed and least in government employees. Majority of victims belongs to lower socioeconomic group (84%). The suicidal deaths by poisoning (97%) being highest followed by homicidal and accidental.

Emerging Training Needs of Forensic Scientists: Addressing the Challenges of Chemical, Biological, Radiological and Nuclear Disasters

In cases of chemical and biological terrorism, many citizens are injured which leads to great social impact. Chemical, Biological, Radiological, and Nuclear (CBRN) detection in-service training for forensic teams is indispensable to incorporate expertise to address concerns on weapons of mass destruction. Forensic science laboratories around the world are determined to fight the changing face of crime in the rapidly advancing technical scenarios globally by continually upgrading its technical acumen and embracing new technologies in its domain. The mission of training of forensic scientists is to prepare nationally accepted guidelines for the forensic examination of CBRN related materials and residues.

Unconventional Adulterants in Seized Heroin Samples: Forensic Insight

Drug abuse is a global predicament. The illicit market of drugs consistently witnesses experiments to deceive law regulatory agencies during manufacturing and trading of these regulated drugs. Drug traders amalgamate core drug compound with other chemical moieties to deceive regulatory agencies, to enhance potency and to escalate the tempt for consumption. Diacetylmorphine, commonly called smack/heroin is substantially seized round the globe, which clearly indicates its large scale abuse. This study presents some unusual additives in 252 seized samples for suspected heroin, referred to Forensic Science Laboratory (FSL), Delhi in the year 2019. The samples were isolated, screened and identified using GC-MS technique. Besides other consistent additives, four unusual novel adulterants were detected in confiscated heroin samples in Delhi, India. The study will update forensic chemical experts in detection of new adulterants in seized drugs, besides disseminating awareness and knowledge among those concerned with drug regulation, monitoring and policy making.

Forensic identification of missing persons using DNA from surviving relatives and femur bone retrieved from salty environment

Human identification using forensic DNA profiling has made enormous advancement over the past two-and-half decades. Forensic DNA profiling provides enormous genetic data from a variety of biological materials and individuals to help solve many important criminal and civil cases that confront society. Under certain environmental conditions, the total deterioration of soft-tissue leaves skeletal remains as the only available sample for DNA testing to identify missing persons, victims of natural disasters, or exonerate suspect(s) in a criminal case. We report the findings of a case involving the human remains of a missing person submitted to the Forensic Science Laboratory of the Ghana Police Service for forensic DNA profiling in comparison to an alleged living relative of the deceased. DNA from the femur bone and buccal swabs of alleged relative of the deceased were extracted, quantified, and short tandem repeat (STR) profiled using Qiagen's Investigator kit, Applied Biosystem's Quantifiler trio, and GlobalFiler kits. Full STR profiles were generated for both the femur bone from the salty environment and the buccal swabs from the alleged relative. The femur bone was genetically identified to be that of the missing person. The remains were thus handed over to the relatives for final funeral rites and burial to bring closure to the long search for the missing person.

Detection of fentanyl in binary mixtures with cocaine by use of surface-enhanced Raman spectroscopy

The ongoing epidemic pertaining to overdose deaths has been attributed to the synthetic opioid fentanyl due to its use as an adulterant in other, less potent drugs of abuse. Detection of low quantities of fentanyl would, therefore, be extremely useful in a forensic science laboratory. While Raman spectroscopy is particularly effective at distinguishing between classes of drugs, weak signatures can prove difficult when dealing with microscopic samples. Surface-enhanced Raman scattering spectroscopy provides the enhancement necessary to make Raman a viable approach for the detection of small amounts of fentanyl. This work explores the use of a paper-based substrate loaded with silver nanoparticles for the recovery of small quantities of fentanyl in cocaine, where it was identified at a lower limit of 500 ng (∼65 ppm) in mixtures. Linear relationships were investigated between intensity and concentration for diagnostic peaks associated with fentanyl and cocaine, which in turn sheds light on the attenuation of the enhancement intensity as a result of competitive binding to silver nanoparticles. This work demonstrates a potentially simple and qualitative pathway for the forensic analysis of fentanyl as an adulterant in cocaine.

Forensic examination of handwriting and thumb impression-A case study

Handwriting Science and Finger Print examination both are significant branches of Forensic Science. This article illustrates one of the important cases related to cheating by impersonation in constable recruitment examination. The case was submitted in Central Forensic Science Laboratory CBI, New Delhi for examination and opinion on handwritings as well as finger thumb impressions with detailed questionnaires. Inter see examination and comparison of questioned document with standard document reveals that both the sets were consistent in detailed characteristic features and execution of strokes in construction of letter and their combination in words. The authorship of questioned documents was matched with the supplied specimen documents. Also, the questioned thumb impressions were compared with the standard thumb impression and were found consistent between both the sets. The case was examined thoroughly by applying the principle of handwriting science and finger thumb impression. The case was successfully solved on the basis of forensic analysis of handwritings and finger thumb impressions. The scientific evidence was produced during court testimony by the experts and opinion was accepted in the court of law and finally the suspected person was convicted. Keywords: Questioned document examination, Thumb impression, Forensic examination.

TLC Detection and Theoretical Structure Elucidation of Nitrogen Containing Compounds with Cobalt Thiocyanate

Forensic Science Laboratories of Maharashtra state, India, receives large number of poisoning cases pertaining pharmaceutical drug overdose and illicit drugs. Thin-layer chromatography (TLC) is a method of choice for chemical analysis due to large number of biological/non-biological samples received. This study reports cobalt thiocyanate reagent to be more effective in detecting nitrogen containing drugs like chloroquine, chlorphenamine, mephedrone, cocaine, ketamine in addition to pesticides like pretilachlor, thiamethoxam and tebuconazole when aided by TLC. These compounds (except for ketamine which gives purple) form blue color when reacted with cobalt thiocyanate due to the formation of tetrahedral cobalt (II) thiocyanate complex. However due to lack of experimental evidences, quantum mechanical calculations have been employed to deduce their structures. The theoretical structure elucidation methodology is based on examining crystal structures of ligands having similar structural relationship to present drug molecules and investigating reactive sites in each drug molecule via. Molecular Electrostatic Potential.

Useful working tool to develop fingerprints on adhesive tapes with powder suspensions

The majority of forensic laboratories use powder suspensions such as “wet powders” to develop fingerprints on adhesive tapes. These solutions are made of water, detergent, and particles that colour the mixture black or white. They are applied with a brush onto the surface to be treated. The operation may be complicated according to the length of the adhesive and the ability to wash off the tape using running water. In order to simplify the use of this method involving powder suspensions, the Fingerprints Unit of the Forensic Science Laboratory of the French Gendarmerie has developed a new working tool to facilitate treatment, rinsing and waste management.

Forensic Science and Scientific Investigation

The precise proof of a crime using objective evidence is becoming increasingly important as Japan's crime rate climbs. This need arises not only from the current high rate of anonymous crime, but also the introduction of a Saiban-in (citizen judge) system, and the increased silence of suspects following investigation visualization. Forensic science is an academic field that investigates legal (and illegal) matters using science, and subsequently applies research results to resolving real crime cases. Materials examined during forensic practice include both common specimens, such as fingerprints, footprints, blood stains, and hairs, and less common specimens, such as soils, plants, dust, and pollens. In the event of biological, chemical, or explosive terrorism, air and surface wipe specimens-possibly containing chemical warfare agents, microbes, and explosives-can become critical target materials. Alternatively, on discovering powders and/or liquids that are suspected to be illegal drugs, preliminary tests are performed at the crime scene itself. Subsequently, confirmatory examinations are performed at a forensic science laboratory. Current research efforts are underway to develop simpler and more reliable tools for on-site drug testing, and to develop analytical methods capable of differentiating regioisomers of drugs, performing drug metabolism studies as a way to identify drugs of abuse, and studying the organic synthesis of authentic standard compounds. In this review, we outline current state-of-the-art technologies in forensic chemistry.