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This study reports the genetic diversity and phylogenetic relationships of 24 autosomal short tandem repeat (STR) loci in 210 unrelated Santhal individuals from the Lakhisarai and Jamui districts of Bihar, India, genotyped with the Ingenomics™ AutoProfiler STR Kit. All 24 loci were polymorphic and forensically informative: polymorphism information content ranged from 0.601 (CSF1PO) to 0.933 (SE33), power of discrimination from 0.814 to 0.988 and power of exclusion from 0.428 to 0.913, with a combined probability of match of 2.41 × 10⁻²⁸ and a combined power of exclusion of 0.999999999991. No locus deviated significantly from Hardy–Weinberg equilibrium. Population relationships were examined against 34 previously published, geographically and ethnically relevant Indian datasets using a neighbour-joining tree based on Nei’s Dₐ genetic distance and a principal component analysis of allele frequencies. The neighbour-joining tree placed the Bihar Santhal adjacent to the Munda population of Jharkhand, consistent with the shared Austroasiatic ancestry of the two groups in the Chotanagpur region, although bootstrap support for this node was low. In the principal component analysis the Santhal fell within a dense central cluster containing most of the eastern, northern and central Indian populations examined, with the first two components accounting for 81.47
This article reports the allele frequency distribution and statistically calculated the forensic efficiency parameters of 210 unrelated volunteers that belong to a specific tribal group named Santhal living in Bihar, India. 24 specific short tandem repeat (STR) markers are included in this study by using the Ingenomics™ AutoProfiler STR Kit. The Power of discrimination (PD), power of exclusion (PE), observed heterozygosity (Ho), expected heterozygosity (He) polymorphism information content (PIC), probability of match (PM), typical paternity index (TPI) and Hardy–Weinberg equilibrium (HWE) p-value were calculated. The result shows that the probability of match (PM) values across the loci ranged from 0.012 to 0.186, while the power of discrimination (PD) varied from 0.814 to 0.988. The highest PD values were observed at SE33 (0.988), Penta E (0.983), and FGA (0.962), indicating their strong ability to differentiate individuals within the population. Conversely, loci such as CSF1PO (0.814) and D2S441 (0.844) showed comparatively lower discrimination power. The polymorphism information content (PIC) values ranged from 0.601 to 0.933, with most loci showing PIC values greater than 0.7, reflecting a high degree of polymorphism. Gene diversity values were also high across the studied loci, ranging from 0.666 to 0.939, further confirming the substantial genetic variability present in the population. The power of exclusion (PE), which is an important parameter for paternity testing, ranged from 0.428 to 0.913, with SE33 and Penta E showing the highest exclusion capacities. The typical paternity index (TPI) values varied from 1.667 to 11.667, again highlighting the strong contribution of highly polymorphic loci such as SE33, Penta E, and D12S391. The combined probability of match (CPM) was 2.41 × 10⁻28, combined power of exclusion (CPE) was 0.999999999991, combined paternity index (CPI) was 3.51 × 1010 and combined power of discrimination was 1 providing very strong statistical support for the application of these markers in paternity testing. These results demonstrate that the 24 autosomal STR loci possess high forensic efficiency and are highly informative for forensic identification and kinship analysis in the santhal population.
The reliable identification of anaesthetic and opioid drugs in biological matrices is of critical importance in forensic toxicology, particularly in cases of drug misuse and suspected medical malpractice. Given the typically low concentrations of these analytes in postmortem samples, an efficient extraction and preconcentration strategy is indispensable. Capsule phase microextraction (CPME), a recently developed sol-gel–based sample preparation technology that encapsulates sorbents within a porous tubular polymeric membrane, was employed for the selective isolation of anaesthetics (bupivacaine, lidocaine, ropivacaine, and prilocaine) and the opioid (tramadol) from postmortem blood and tissue samples (liver, kidney, stomach, and spleen). Subsequent analysis was performed using gas chromatography–mass spectrometry (GC–MS). The optimized CPME-GC–MS method exhibited excellent analytical performance, achieving linear calibration ranges of 0.01–1.0 μg mL⁻¹ in blood and 0.01–1.0 μg g⁻¹ in tissue samples, with limits of quantification as low as 0.0060–0.0079 μg mL⁻¹ (blood) and 0.0080–0.0099 μg g⁻¹ (tissues). Precision studies confirmed strong method reliability, with intra-day repeatability below 5% and inter-day reproducibility below 10%. The method was successfully applied to authentic postmortem specimens from a suspected fatal intoxication case attributed to medical negligence involving anaesthetic and opioid drugs. Beyond its forensic applicability, the environmental and operational sustainability of the protocol was critically evaluated using ComplexMoGAPI, AGREE and CACI assessment tools, confirming the method’s greenness and practicality. Overall, the CPME-GC- MS workflow offers a robust, sensitive, and eco-friendly analytical platform, representing a significant advancement for drug monitoring in medico-legal investigations.
Forensic soil evidence plays a crucial role in post-blast investigations, offering valuable insights into event reconstruction and establishing connections between individuals, locations, explosives, and devices. This study presents a comprehensive method for forensic soil evidence collection and analysis, focusing on the identification of nitrate ions in inorganic explosives. The methodology involves a systematic survey of the blast scene, sample collection from various locations, and proper documentation to maintain the chain of custody. Visual examination, physical and chemical analyses, and statistical validation were performed to characterize the soil composition and identify traces of explosive materials. Fourier Transform Infrared Spectroscopy (FTIR) and Ion Chromatography (IC) were employed to differentiate soil samples and provide insights into their matrix effect for qualitative and quantitative analysis of trace explosive elements. The study demonstrates the effectiveness of the proposed method across three scenarios: the effect of soil matrix on nitrate recovery, post-blast soil analysis from pyrotechnic debris, and field simulation under adverse environmental conditions. The results highlight the importance of optimizing soil sample mass, timely collection, and a multi-modal analytical approach combining chemical spot tests, FTIR confirmation, and IC quantification. The findings underscore the challenges posed by environmental factors and emphasize the need for standardized protocols and capacity building in regional forensic laboratories. This research provides actionable insights to enhance forensic outcomes in criminal and anti-terror investigations, contributing to the advancement of forensic soil analysis in post-blast scenarios.
This study presents, for the first time, an integrated analytical strategy combining a rotating paper disc (RPD) microextraction device with in-injector micro-reaction (IIMR) for the determination of seven non-steroidal anti-inflammatory drugs (NSAIDs) in postmortem biological matrices. The proposed approach employs a cellulose-based sorptive phase impregnated with octanol, enabling efficient and low-cost extraction through enhanced amphiphilic. The design of RPD device promotes efficient mass transfer and facilitates direct immersion into complex matrices such as liver, blood, and urine, allowing rapid and effective analyte uptake without the need for complex sorbent synthesis or extensive sample handling. The IIMR concept represents an on-line, instrument-mediated and non-discrete transformation that occurs directly within the GC injection port during sample introduction, thereby eliminating any additional derivatization step. This embedded micro-reaction proceeds instantaneously under injector conditions (within seconds), requires no external heating or reaction time, and consumes ultra-low volumes of reagent (1 μL), significantly improving analytical throughput and reducing chemical usage compared to conventional derivatization protocols. Under optimized conditions, the method exhibited satisfactory linearity (0.1-10 μg mL-1 or μg g-1), good accuracy (86.8-101.1%), low limits of quantification (0.033-0.099 μg mL-1 or μg g-1), and excellent precision (1.8-10.7%). The overall analytical workflow demonstrated strong alignment with green and white analytical chemistry principles, as confirmed by AGSA (70.83) and BAGI (70) scores. The method was successfully applied to real postmortem liver, urine, and blood samples, highlighting its robustness, operational simplicity, and suitability for routine forensic toxicology applications.
