Synthesis and application of silver nanoparticles from lemon peel extract and other local plant extracts for detection of "blood" at crime scene

Abstract

This study reports the enhancement of luminol's sensitivity for blood detection at a crime scene. Silver nanoparticles (AgNPs) were synthesized from the extracts derived from Citrus limon peels, Aloe vera leaves, Capsicum annuum barks from Salix alba, Crinum asiaticum Linn leaves, and Crinum macowanii bulb using green chemistry procedure. Synthesis of silver nanoparticles followed a green chemistry method utilizing water as a solvent, with the phytochemicals from the extracts acting as stabilizing and reducing agents to reduce Ag(I) to Ag(0). The synthesized AgNPs were characterized using Transmission Electron Microscopy (TEM), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and Ultraviolet-visible (UV-Vis). XRD revealed that the structural composition of silver nanoparticles (AgNPs) was face-centered cubic crystalline (Fcc). TEM imaging demonstrated the spherical crystalline nature of silver nanoparticles (AgNPs) derived from the plant extracts. These silver nanoparticles (AgNPs) were used to enhance the shelf-life, chemiluminescence intensity, specificity, and sensitivity of luminol. It was observed that the silver nanoparticles synthesized from these plant extracts effectively enhanced the chemiluminescence signal of luminol. Moreover, applying plant extracts in blood detection demonstrated a higher fluorescence when exposed to ultraviolet (UV) light.

Keywords: Chemiluminescence; Green chemistry; Plant extract; Silver nanoparticles; fluorescence; forensic science.