Aims
The aim of this practical was to determine the presence of blood on multiple piece of clothing for further analysis by using various preliminary tests and to see the rate and duration of chemiluminesence of the Phadebas paper test.
Introduction
To a forensic investigation blood is of unparalleled importance, it has multiple functions in a forensic investigation; The book criminal investigation (Christine Hess Orthmann, Kären Hess, 2012) states “blood assists in establishing that a crime was committed, in re-creating the movements of a suspect or victim and in eliminating suspects”. During a crime, more commonly violent ones, blood leaves recorded history of the events that have occurred to this end It has been said in Forensic science …show more content…
This colour was maintained throughout the experiments duration neither pigment or luminescence changed over the 41 minutes. According to a study by Eva-Lena et al, 2011 saliva, due its high amylase concentrations, has a near instantaneous reaction which is what was observed on the Phadebas paper strip and what was expected as we knew that it was saliva sample. The known negative sample didn’t cause a colour change at all throughout the experiment as is anticipated as there should have been no amylase to react …show more content…
One thing to note is that I would recommend that new samples be taken from the clothing at each testing stage and not to use the samples tested with LMG as according to a study by Alenazy, Refaat and Babu, 2015 the use of LMG to test samples that then go off for DNA analysis produce poor partial profiles, apparently due to the longevity of the LMG chemiluminescence
The aim of this practical was to determine the presence of blood on multiple piece of clothing for further analysis by using various preliminary tests and to see the rate and duration of chemiluminesence of the Phadebas paper test.
Introduction
To a forensic investigation blood is of unparalleled importance, it has multiple functions in a forensic investigation; The book criminal investigation (Christine Hess Orthmann, Kären Hess, 2012) states “blood assists in establishing that a crime was committed, in re-creating the movements of a suspect or victim and in eliminating suspects”. During a crime, more commonly violent ones, blood leaves recorded history of the events that have occurred to this end It has been said in Forensic science …show more content…
This colour was maintained throughout the experiments duration neither pigment or luminescence changed over the 41 minutes. According to a study by Eva-Lena et al, 2011 saliva, due its high amylase concentrations, has a near instantaneous reaction which is what was observed on the Phadebas paper strip and what was expected as we knew that it was saliva sample. The known negative sample didn’t cause a colour change at all throughout the experiment as is anticipated as there should have been no amylase to react …show more content…
One thing to note is that I would recommend that new samples be taken from the clothing at each testing stage and not to use the samples tested with LMG as according to a study by Alenazy, Refaat and Babu, 2015 the use of LMG to test samples that then go off for DNA analysis produce poor partial profiles, apparently due to the longevity of the LMG chemiluminescence