Identification of Cat (Felis catus) Blood Splatter on Cotton Fabric After Periods of Drying Using Leucomalachite Green and Takayama Reagent

Blood-stain or blood splatter analysis when used properly can assist in establishing a chain of events linked to violent crimes (Bevel and Gardner, 2008). The methods used in detecting blood splatters in the field are chemical methods. Leucomalachite green is a colorimetric test which is used to test the presence of blood (Castro and Coyle, 2008). Takayama reagent is a confirmatory test for blood (Strassman, 1922). The aim of this research is to detect the blood splatter on cotton fabric after it has been dried for 1 day, 3 days and 5 days using Leucomalachite green and Takayama reagent. Cotton fabric was specifically chosen for this experiment with 3 different periods of drying. The unstained cotton fabric was cut into squares, and a blood sample was splattered on each piece. The fabrics splattered with blood were then dried for 1 day, 3 days and 5 days. The blood splatter was then tested using Leucomalachite green and Takayama reagent, and the results were noted afterwards. For the control, red food dye was dried for 1 day then tested with Leucomalachite green and Takayama reagent. The image results of the Leucomalachite green test are analyzed using ImageJ software 1.8.0_112 where the red, green and blue pixels are converted to grayscale. The image results of the Takayama test are graded based on the number and pattern of crystal. In conclusion, Leucomalachite green and Takayama reagent are able to detect cat blood splatter on the cotton fabric. Leucomalachite green produced a higher intensity/ darker colour as a result of an older sample, and the lower intensity/ lighter colour as a result of a fresher sample of the Leucomalachite green test. Takayama reagent produced a densely packed pattern of crystals as a result of an older sample, and the loosely packed pattern of crystals as a result of a fresher sample of the Takayama test.

Micro flow injection analysis of leucomalachite green in fish muscle using modified henequen fibers as microfluidic channels

In this work a simple and novel procedure for leucomalachite green determination based on micro flow injection analysis (μFIA) with amperometric detection is presented.

Validation of an UHPLC-MS/MS Method for the Determination of Malachite Green, Leucomalachite Green, Crystal Violet, and Leucocrystal Violet in Shrimp, Fish, and Salmon Muscle Using a Modified QuEChERS Approach

A quantitative and confirmatory method for detecting the presence of triphenylmethane dyes in shrimp muscle using ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) and a quick, easy, cheap, effective, rugged and safe (QuEChERS) extraction approach was validated. The method exhibited linearity and selectivity and the coefficient of determination (R2) was higher than 0.95 for all studied analytes. Limits of detection (LODs) varied from 0.32 to 0.44 µg kg-1 and the limit of quantification (LOQ) was determined to be 0.5 µg kg-1 for all studied analytes. The trueness, precision, decision limits (CCα), detection capability (CCβ) and uncertainty presented adequate performance. In addition to the validation in shrimp muscle, fish and salmon muscle were also satisfactory validated as an extension of scope. The suitability of the proposed method was also evaluated through an interlaboratory proficiency test, in which satisfactory results were obtained. The fully validated method is thus suitable for the analysis of triphenylmethane dyes in shrimp, fish, and salmon muscle.