A New Chromogenic Spray Reagent for Detection and Identification of Bromadiolone in Biological Samples

A new chromogenic spray reagent is described for chromatographic detection and identification of bromadiolone, a second-generation anticoagulant rodenticide, by TLC. The reagent is prepared by simple diazotization of o-Tolidine by using hydrochloric acid and sodium nitrite. The standard bromadiolone was spotted on TLC (thin layer chromatography) and developed in Chloroform: Acetone and 1 mL Acetic acid (glacial). The prepared reagent is sprayed on the TLC, forming reddish-pink colour adduct with bromadiolone. This method showed selective detection of bromadiolone in the presence of other interfering pesticides; also, it shows reproducibility. The possible mechanism suggests the formation of a diazotized adduct of the reagent with bromadiolone, which shows a stable reddish-pink coloured spot. This method is very useful for the detection of the bromadiolone in the forensically important cases like suicides where it is important to detect the bromadiolone selectively in the presence of other pesticides which could be also used in suicidal or homicidal cases.