Age Estimation of Bloodstained Fingermarks

Alkaline Phosphatase for Estimating the Time since Deposition of Blood Fingerprints by Scanning Electrochemical Microscopy

“…that can offer vital and valuable information about the criminals involved. 3 Usually, the BFPs collected at crime scenes are sent to the forensic laboratory for DNA analysis. 4 Even though a DNA profile can provide the most significant information that directly identifies the suspect, it does not work if the suspect's or victim's touch DNA is not stored in the database or presents in low concentration at crime scenes, which prevents it from being efficiently extracted for forensic analysis.…”

“…and is also the most common contaminant in fingerprints. , Blood fingerprints (BFPs) are major contributors to powerful evidence in criminal investigations because they may contain physical fingerprint patterns (e.g., levels 1–3 features) and abundant chemical or biological components (e.g., red blood cells, white blood cells, platelets, proteins, nucleic acids, lipids, carbohydrates, etc.) that can offer vital and valuable information about the criminals involved . Usually, the BFPs collected at crime scenes are sent to the forensic laboratory for DNA analysis .…”

“…Notwithstanding, the technique needs to be further verified to increase its accuracy and reproducibility for the TSD determination of bloodstains in practice. In addition to red blood cells, the degradation of DNA and RNA in white blood cells was also observed via polymerase chain reaction amplification techniques. , Unfortunately, these markers break down quickly due to exposure to enzymatic processes and thus are not suitable for TSD determination …”

“…Similarities among these attempts suggested that physical changes and chemical or biological degradation in bloodstains have the potential for TSD determination . Red blood cells possess an overwhelming contribution (approximately 50%) of whole blood and thus become a dramatic marker for estimating the TSD . Early works mainly focused on hemoglobin (Hb) degradation.…”

“…17 Red blood cells possess an overwhelming contribution (approximately 50%) of whole blood and thus become a dramatic marker for estimating the TSD. 3 Early works mainly focused on hemoglobin (Hb) degradation. Upon blood exiting the body, the Hb transforms into its Fe 3+ -containing degradation products, methemoglobin (met-Hb) and hemichrome (HC), accompanied by a color change from bright red to dark brown.…”