Near‐Infrared‐Light‐Mediated Imaging of Latent Fingerprints based on Molecular Recognition

Abstract

Photoluminescence is one of the most sensitive techniques for fingerprint detection, but it also suffers from background fluorescence and selectivity at the expense of generality. The method described herein integrates the advantages of near-infrared-light-mediated imaging and molecular recognition. In principle, upconversion nanoparticles (UCNPs) functionalized with a lysozyme-binding aptamer were used to detect fingerprints through recognizing lysozyme in the fingerprint ridges. UCNPs possess the ability to suppress background fluorescence and make it possible for fingerprint imaging on problematic surfaces. Lysozyme, a universal compound in fingerprints, was chosen as the target, thus simultaneously meeting the selectivity and generality criteria in photoluminescence approaches. Fingerprints on different surfaces and from different people were detected successfully. This strategy was used to detect fingerprints with cocaine powder by using UCNPs functionalized with a cocaine-binding aptamer.

Advances in the development and component recognition of latent fingerprints

“…The minimally detectable cocaine loaded was calculated as 90 ng. Yuan et al [75] employed upconversion NPs (UCNPs) functionalized with aptamers for the detection of fingerprints through recognizing lysozyme. The fingerprints treated with UCNPs/ aptamer conjugates displayed a better luminescence image than those treated with fluorescein or CdTe QDs, due to the ability of UCNPs to suppress background fluorescence.…”

Inorganic lanthanide nanoprobes for background-free luminescent bioassays

“…Since the first demonstration of UCL bioassay in 1999 [182], there has been an extensive research on Ln 3+ -doped UCNPs in various bioassay applications [183][184][185][186]. One representative paradigm was reported by Tanke and coworkers [187], who employed Y 2 O 2 S : Yb,Er submicrons as UCL probes in DNA microarrays for the detection of nucleic acid hybrids.…”

Synthesis of NIR-Responsive NaYF4:Yb,Er Upconversion Fluorescent Nanoparticles Using an Optimized Solvothermal Method and Their Applications in Enhanced Development of Latent Fingerprints on Various Smooth Substrates

“…7–21 Among different NPs being studied so far, UCNPs are being considered as ideal probes for developing the latent fingerprints. 22 UCNPs can convert radiation of long wavelength (e.g., near-infrared (NIR) light) into emissions of shorter wavelength (e.g., visible light) via a two-photon or multiphoton mechanism. 23–32 They are excited by NIR light to emit strong visible fluorescence.…”

“…Recently Wang et al reported the use of a solution of NaYF 4 :Yb,Er UCNPs functionalized with lysozyme-binding aptamer for recognizing the lysozyme in the sweat associated with the fingerprints for the detection of fingerprints. 22 However, this method contained complicated steps and was not practical at crime scenes because it required chemical modification of the large UCNPs (~260 nm) through tedious procedures and long-time incubation of fingerprints with the UCNPs solution for 30 min.…”