How Do Forensic Scientists Test Blood? Blood detection The most publicized test by crime shows is the Luminol process in which a chemical is sprayed onto a surface where blood is suspected to be. The chemical reacts with traces of blood, producing a chemi-luminescence, or apparent glow, as a result of the chemical reaction that
How Do Forensic Scientists Analyse Drugs? Forensic drug chemists analyze samples of unknown materials including powders, liquids and stains to determine the chemical identity or characteristics of the compounds that make up the sample. Samples submitted as evidence in a drug-related case can contain one compound or a mixture of many compounds. What is the
What Will The Precipitin Test Tell A Forensic Scientist? Precipitin test identifies the presence of proteins that are found only in human blood. On the surface of red blood cells are molecules (proteins) called antigens. Antigens allow a living system to recognize foreign biological substances, such as infectious agents and allergens. What is a precipitin
What Is A Presumptive Test In Forensics? A presumptive test is a qualitative analysis that allows to identify, or confirm, the presence of a substance in a sample. These determinations usually occur, after a chemical reaction, and a specific colour is produced. A false positive is another substance reacting the same way, producing the expected
Can You Challenge A Positive Drug Test? If a false positive occurs, you can talk to your employer to determine the options available to you. It should also be noted that if you wish to challenge a positive test result, the process of appeal may vary according to the state or the company where it