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Chemistry and People's Choice Winner of Dance Your PhD 2017
Based upon the PhD Research of Natália Oliveira entitled "Development of biosensors for Forensic Sciences applications" at the Laboratory of Immunopathology Keizo Asami, Federal University of Pernambuco, Brazil.
Dancers: Natália Oliveira, Edson Vogue, Amethyst Quartzo, Wanderson César, Lúcio Souza Juliana Damasceno e William Silva
Choreography: Vogue 4 Recife
Director of Photography and Editor: William Oliveira
Music theme "Chega, vai" by Eu e A Duplicata.
Listen: • Eu e A Duplicata - Che...
Filmed at Laboratory of Immunopathology Keizo Asami (LIKA) and at the historical area of central Recife (Recife Antigo)
Please find more information at:
doi.org/10.1016/j.fsigss.2015...
I wish you have fun and enjoy the video!
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The detection and identification of human body fluids in a crime scene are important aspects in forensic sciences. Defining whether or not a sample is present in an area may provide clues enough to influence the outcome of criminal investigations. In order to prove the presence of stains (such as blood, semen and saliva), confirmatory tests are performed, relying usually in colorimetric, crystallographic and immunochromatographic assays.
However, as criminals try to avoid leaving clues at a crime scene, body fluid stains are often washed away with household cleaners, which may destroy the molecular targets of those tests. Thus, the development of new technologies, such as biosensors, may overcome those problems, by combining a biomolecule (such as proteins and nucleic acids) with a transducer - an electronic device that converts one form of energy into other - and a signal processor.
In this research, I proposed a DNA biosensor as a model for a confirmatory test for human body fluids detection. In this system, a single strand DNA molecule (named as probe, represented by the boy with purple shirt) was attached to the surface of a graphite electrode in order to interact with a nucleotide sequence that is complementary to the probe (target, the boy with black shirt). This coupling was detected by electric current peaks produced on electrode surface (the boy lying on the floor with red shirt).
The biosensor was able to distinguish the current peak signals obtained from the probe and the target. Also, when biological samples contamination was simulated by immersing the electrode modified with the probe in solutions containing bleach, alcohol and detergent mixed with the target, the biosensor was still able to recognize the sample. These findings suggested that DNA biosensors have a great potential to be used as a confirmatory test to detect human body fluids in crime scenes.