Forensic Entomotoxicology: A Brief Look at Sample Preparation Techniques – A Review

Abstract

Forensic entomotoxicology is a relatively new science whose applications aims the detection of toxic substances through a matrix of necrophagous insects in a crime scene. In addition, it aims the investigation of the impacts of the xenobiotics on these insects, generating impacts in the measurement of the post-mortem interval (PMI). Calliphoridae larvae, the most important insect for forensic entomology, has an average amount of 25% of crude fat and 53% of crude protein, being a complex matrix that requires some sample preparation methodology before inserting the sample in some equipment to perform the chemical instrumental analysis. Sample preparation methods should be applied in order to increase the protection of analytical equipment from impurities present in the arthropod matrix, as well as increase the detectability of the test analyte by the analytical instrumentation of choice. Thus, the objective of the present work is to compile sample preparation techniques since traditional procedures until new approaches found in the scientific literature applied for entomotoxicological analysis in Calliphoridae specimens and respective analytes. It was observed the lack of a complete standardization for entomotoxicological approach, mainly for traditional extractions preparations. In this sense, microextraction-based techniques become an even greater challenge for arthropod–like matrix, especially in specimens from Calliphoridae family for xenobiotics determination. So, the development of sample preparation techniques with more sustainable approaches, such as reduced use of solvents, added to the increase of the powerfulness of analytical instrumental techniques should be encourage in order to improve the forensic entomotoxicology approach.