Adli Kimyada Spektrofotometri Metoduyla GSR Analizi

Year 2023, Volume: 12 Issue: 2, 335 - 350, 30.12.2023

Gökhan Tekin , Ercan Seyhan , Işıl Aydın , Fırat Aydın

https://doi.org/10.55007/dufed.1356588

Abstract

Bu çalışma, adli kimya uygulamalarından atış artıkları analizlerine yönelik olarak yapılmıştır. Verimli sonuçlar elde etme yöntemlerinden olan Enerji Dağılımlı X-Işını Analizörlü Taramalı Elektron Mikroskobu (SEM-EDS) ve Grafit Fırınlı Atomik Absorpsiyon Spektrometresi (GFAAS) cihazları ile analiz surecinin tamamı değerlendirilmiş, elde edilen verilerin mukayeseleri yapılarak olumlu sonuçlar elde edilmeye çalışılmıştır. Analiz işlemi bitiminde hangi sonuçların daha sağlıklı olduğu ele alınmış, numunelerin özellikle tekrar analiz etmeye uygunluğu üzerinde durulmuştur. SEM/EDS cihazı ile yapılan analizlerde tüm numuneler üzerinde atış artıklarının varlığı belirlenmiş, ancak aynı numuneler GFAAS cihazı ile analiz edildiğinde sonuçlar, atış artıkları varlığına işaret eden antimon derişimi olan 10 μg/L’lik eşik değerin altında kalmıştır. Elde ettiğimiz değerlerin atış artığı taneciklerinin büyüklük ve ağırlıklarıyla değişkenlik gösterebileceği unutulmamalıdır. SEM/EDS cihazı ile analiz yöntemi her ne kadar maliyetli bir yöntem olsa da numune toplamadaki kolaylık, analiz sürecine ekstra hiçbir işlem yapmadan geçiş ve analizlemede numune üzerindeki atış artıkları haricindeki başka elementleri de tespit etme özelliği ile derişimi eşik değer altındaki tanecikleri de belirleme durumlarından dolayı daha uygun olduğu değerlendirilmiştir.

Keywords

Adli Kimya, GSR, Antimon, GAAFS, SEM/EDS.

GSR Analysis by Spectrophotometry Method in Forensic Chemistry

Abstract

This study was conducted to analyze residual shots from forensic chemistry applications. The entire analysis process was evaluated with Scanning Electron Microscopy/Energy Dispersive X-Ray Spectroscopy (SEM/EDS) and, Graphite Furnace Atomic Absorption Spectrometry (GFAAS)devices, which are among the methods for obtaining efficient results, and positive results were tried to be obtained by comparison. Following the study, it was discussed which results were more appropriate; in particular, the samples' appropriateness for reanalysis was underlined. The presence of shot residues on all samples was determined in the analyses performed with the SEM/EDS device. When the same samples were analyzed with the GFAAS device, the results remained below the threshold value of 10 μg/L, which is the antimony concentration indicating the presence of shot residues. It should be noted that the values we obtained may vary with the size and weight of the shot residue particles. Due to the ease of sample collection, the capacity to identify elements other than gunshot residues on the sample under examination, and the circumstances surrounding the determination of particles below the threshold value, the analysis method utilizing the SEM/EDS device has been deemed more suitable despite its higher cost.

Keywords

Forensic Chemistry, GSR, Antimony, GAAFS, SEM/EDS

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