四苯乙烯磁性粉在指印显现中的应用研究OA

Fingerprints represent one of the most common types of physical evidence found at crime scene,characterized by their uniqueness to each individual,lifelong stability,capacity to leave traces upon contact,and ability to identify individuals.Recently,aggregation-induced emission(AIE)materials,particularly tetraphenylethylene,have garnered increasing research interest in forensic science due to their potential applications.Tetraphenylethylene can effectively develop latent fingerprints at crime scenes by selectively adsorbing endogenous fingerprint secretions.This study aimed to determine the optimal ratio and excitation wavelength of tetraphenylethylene-incorporated magnetic powder for fingerprint development.We evaluated its efficacy in developing fingerprints with varying substance compositions,on diverse surfaces,in continuous impressions,and at different remaining time,while comparing it to AIE magnetic fingerprint powder and green emitting phosphor.The results indicated that a mass ratio of tetraphenylethylene to iron powder at 1∶70,combined with at 365 nm ultraviolet excitation,yielded the most favorable fingerprint development outcomes.This formulation exhibited high fluorescence intensity while maintaining low background powder deposition.Tetraphenylethylene magnetic powder demonstrated robust performance in revealing both sweat and sebaceous fingerprints,demonstrating versatility across various surfaces.In case of continuous fingerprinting,it clearly visualized the tenth sweat fingerprints impression.Additionally,the powder showed potential in developing aged fingerprints,successfully revealing sweat fingerprints up to 15 days old and sebaceous fingerprints up to 30 days old.In summary,tetraphenylethylene magnetic powder has demonstrated exceptional performance and broad application potential in fingerprint development.