SURFACE RECOVERY AND CHEMICAL PROFILING OF PARACETAMOL FOR FORENSIC INVESTIGATION

Abstract

Paracetamol or acetaminophen is an analgesic medicinal drug which is not controlled. Due to its easily accessibility at relatively cheap price, this medicinal drug has been reported in a number of poisoning cases either accidental consumption or attempted suicide. Besides, as a common cutting agent in illicit drugs, it possesses high possibility to be detected in clandestine laboratories. It has also been reported with the existence of counterfeit paracetamol in local market which carries severe risk towards the consumer due to its unknown ingredients. Therefore, the study was aimed to characterise the profiles of paracetamol tablets, and subsequently explore the surface recovery of paracetamol residues from common household surfaces, simulating cases of clandestine laboratories. In this study, 15 paracetamol tablets of various brands were firstly observed through physical examination to investigate the colour, dimension and shape. Subsequently, all samples were subjected to attenuated total reflection-Fourier transform infra-red spectroscopy (ATR-FTIR) followed by principal component analysis to evaluate the similarities or differences among samples. The paracetamol samples were also analysed by gas chromatography (GCFID) technique to confirm the presence of paracetamol, and also to determine the dosage of each tablet as compared to the claimed dosage. Thin layer chromatography (TLC) was also performed to determine the colourant used in manufacturing the tablets. Lastly, surface recoveries of paracetamol residues from common household surface were studied. Based on physical examination, majority of the paracetamol appeared in white colour either in cylindrical or elliptical shape. ATR-FTIR coupled with chemometric method formed three major clusters suggesting similarities in their FTIR profiles for samples located in the same cluster. GC technique detected paracetamol in all samples, and the amount of active compounds were found to be varied at less than 20%, except one sample which needs re-clarification. TLC analysis also showed to be good in discriminating samples. Compilation of physical and chemical information could provide clue to determine their similarities between samples and also to discriminate certain samples. Recovery study showed that paracetamol residues can be detected from common household surfaces, but the percentage of the recovery could be further maximised through further investigation. To conclude, the physical characterisation and chemical profiling of paracetamol tablets allowed their differentiation among samples. This study was an early stage of paracetamol profiling which involved only 15 samples, but it is worth to be explored in the future to reach beneficial forensic intelligence.

DETECTION OF ANIMAL DNA IN PROCESSED FOOD CONTAINING MILK AND EGG USING mericon® MeatTracker Kit

Abstract

The real-time PCR technique is increasingly being applied for the detection of a number of meat species like beef, pork, chicken, lamb, horse and duck among others. The main objective of this study is to detect animal DNA in processed food containing milk and egg using mericon® MeatTracker kit. Hence several samples were collected from the supermarket which contained egg or milk or milk derived products. DNA extraction was carried out using the DNeasy® mericon Food kit and real-time PCR amplification was performed using mericon® MeatTracker Kit. The extracted DNA was quantified using NanoDropTM spectrophotometer and amplified amd detected using Applied Biosystem 7500 Real-Time PCR system. The highest and the lowest concentration of extracted DNA from the collected samples being respectively 99.4 ng/μl and 5.1 ng/μl and also with desired purity of extracted DNA solution it was expected to perform a successful PCR amplification followed by the detection of animal DNA. However, none of the samples had detectable DNA which could achieve significant threshold cycle value in PCR analysis. Though, through this experimental study we were unable to detect animal DNA from the limited collected samples and the results were also negative, yet there is a possibility that animal DNA from non-meat sources can be detected using mericon® MeatTracker Kit in future study if different and a wider range of processed food samples are considered and high yield DNA can be achieved from the extraction.