Forensic Science 4.5 Essay Example | Topics and Well Written Essays - 500 words

Forensic Science 4.5 - Essay Example One of the most important pieces of evidence is blood but usually by the time the police and the forensic scientists reach the scene of crime the blood is usually dried up. In this article we will learn the four different methods used to collect dried blood samples from the crime scene. These dried blood stains are attained from objects or various surfaces that do not have the ability of mobility and cannot be collected easily. The four methods are cutting, swabbing, scraping and elution (that is dissolving). Cutting is clearly appropriate only to the items or objects that can simply be cut off. Inspectors should not just simply cut off pieces from objects that can be presented intact for example shirts or clothing items. Sometimes bloodstains might be found on objects that according to the inspectors are too large or too complicated to bring in complete for example bloodstains on sofas or on the seats of a vehicle. In such cases, cutting of a portion big enough to have unstained sections on the edges for later comparisons is a good idea because taking in the whole sofa or vehicle seat is not a wise or suitable act (Gaensslen, Harris & Lee, 2008). Swabbing comprises the transferring of the blood sample from the surface on which it was onto some kind of swab. While working with dried blood it is necessary to humidify or to dampen the swab so that the blood sample can be transferred. The solution that is used in the swab has to be sterile so that it avoids any chances of the contamination of the blood sample from bacteria. Gauze sponges are usually more recommendable as they are already sterile and are more functional as swabs. Swabbing is useless in taking out blood samples from walls or even from tables or chairs (Gaensslen, Harris & Lee, 2008). Scraping comprises of utilizing an instrument with a straight or sharply edged face to scrape off the dried blood samples from a surface and to place it onto a clean laboratory glass plate