Preparation of Aptamer-functionalized Au@pNTP@SiO2 Core-Shell Surface-enhanced Raman Scattering Probes for Raman Imaging Study of Adhesive Tap Transferred-Latent Fingerprints

Adhesive tape combined with the core-shell SERS nanoprobe was used to recognize the latent fingerprints on the surface of the object, which provided an effective solution for the imaging of latent fingerprint on large immobile object and surface object. First, Au@ pNTP@ SiO2 SERS probes modified by aptamers specific to lysozyme was prepared and characterized by TEM/EDS. The SERS enhancement activity was also tested. Then the probe was incubated with the aged-latent fingerprints on the surface of different object. Afterwards, the dried latent fingerprint with modified SERS probes was transferred on the adhesive tape and imaged under the confocal Raman microscope. The results showed that the size distribution of the core-shell SERS probe was uniform, mostly concentrated in 60 nm , leading to excellent stability and dispersity. The SERS probe also had enhanced SERS effect, strong SERS intensity and reproducibility with the characteristic peak at 723 , 855 , 1081 , 1343 and 1572 cm(-1), which was consistent with the previous reports. When applied this SERS probe into the tape-transferred latent fingerprint's imaging, not only the first-level structure ( pattern) of fingerprint but also the second structure of fingerprint such as the ridge interruption and ridge fork could be clearly seen. The successful development of the SERS imaging of transferred latent fingerprint on adhesive tapes combined with the aptamer-functionalized SERS probe provides an effective method for recognizing latent fingerprints in forensic science, which also has the potential application in the other areas such as food safety and public safety testing.