title: Rapid visualization of latent fingermarks using gold seed-mediated enhancement.
abstract: BACKGROUND
  Fingermarks are one of the most important and useful forms of physical evidence in forensic investigations. However, latent fingermarks are not directly visible, but can be visualized due to the presence of other residues (such as inorganic salts, proteins, polypeptides, enzymes and human metabolites) which can be detected or recognized through various strategies. Convenient and rapid techniques are still needed to provide obvious contrast between the background and the fingermark ridges and to then visualize latent fingermark with a high degree of selectivity and sensitivity.
  
  
  RESULTS
  In this work, lysozyme-binding aptamer-conjugated Au nanoparticles (NPs) are used to recognize and target lysozyme in the fingermark ridges, and Au+-complex solution is used as a growth agent to reduce Au+from Au+to Au0on the surface of the Au NPs. Distinct fingermark patterns were visualized on a range of professional forensic within 3 min; the resulting images could be observed by the naked eye without background interference. The entire processes from fingermark collection to visualization only entails two steps and can be completed in less than 10 min. The proposed method provides cost and time savings over current fingermark visualization methods.
  
  
  CONCLUSIONS
  We report a simple, inexpensive, and fast method for the rapid visualization of latent fingermarks on the non-porous substrates using Au seed-mediated enhancement. Au seed-mediated enhancement is used to achieve the rapid visualization of latent fingermarks on non-porous substrates by the naked eye without the use of expensive or sophisticated instruments. The proposed approach offers faster detection and visualization of latent fingermarks than existing methods. The proposed method is expected to increase detection efficiency for latent fingermarks and reduce time requirements and costs for forensic investigations.
authors.affiliation: Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, 833, Taiwan.|Department of Biomedical Imaging and Radiological Sciences, National Yang Ming University, Taipei, 112, Taiwan.
authors.forename: Chia-Hao
authors.initials: CH
authors.lastname: Su
authors.affiliation: Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, 833, Taiwan.
authors.forename: Chun-Chieh
authors.initials: CC
authors.lastname: Yu
authors.affiliation: Department of Chemistry, Chinese Culture University, 55, Hwa-Kang Road, Yang-Ming-Shan, Taipei, 11114, Taiwan. zfy3@ulive.pccu.edu.tw.
authors.forename: Fong-Yu
authors.initials: FY
authors.lastname: Cheng
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry*; D003878:Dermatoglyphics; D044707:Forensic Sciences / Q000379:methods*; D006046:Gold / Q000737:chemistry*; D006801:Humans; D053768:Metal Nanoparticles / Q000737:chemistry*; D009113:Muramidase
chemical_list: D052157:Aptamers, Nucleotide; D006046:Gold; D009113:Muramidase
keywords: Aptamers; Au nanoparticles; Au seeds; Fingermarks; Lysozyme