Detection Of Latent Fingerprints Research Articles

L-histidine doped CDs from Zingiber Montanum using hydrothermal method to enhance its antimicrobial activity and imply for latent fingerprint detection

Carbon dots (CDs) from Zingiber Montanum as a natural resource were prepared and tested as an antimicrobial activity with various types of bacteria. Then nitrogen doped carbon dots (N-CDs) were subject to obtain from the plant extract doped with L-histidine using hydrothermal method, indicating their N-CDs fluorescence intensity increases, and can be visualized more brightness under UV lamp compared with its bare CDs. Besides its antimicrobial purpose, fingerprint image is utmost known as one of the important characteristics of the crime evident, in this study, the N-CDs are then aimed to apply on various non-porous material surfaces for latent fingerprint detection. It was shown that the fine powder of N-CDs mixed with starch give more detailed minutiae compared with that from black commercial powder. The applicable fingerprint tracer using this N-CDs/starch powder shows a bit long time clear results until 90 days, indicating that the new N-CDs developed enhances much more the fingerprint performance than its usual. In addition, to confirm the antimicrobial activity the N-CDs alone were also used for such antimicrobial testing via agarose disk diffusion assay against both gram negative and gram-positive bacteria, resulted satisfactorily that this nanomaterial can be a high potential use for antibacterial activity.

Development of dual-channel fluorescent mesoporous SiO2 nanosphere-coated yttrium aluminum garnet composites for sensitive detection of latent fingerprints.

In this study, we investigated the detection of latent fingerprints (LFPs) using green light- and near-infrared (NIR) light-induced up/down-conversion dual-channel composites. Upconverted yttrium aluminium garnet (YAG) was prepared using a citric acid-assisted sol-gel method. After loading rhodamine 6G (RhD-6) into mesoporous silica nanospheres (MSNs), the MSNs-RhD-6 composites were coated with the as-synthesised YAG via electrostatic adsorption using the layer-by-layer method, demonstrating reversible switching between yellow and green light waves under 525 nm green light or 980 nm laser excitation. To evaluate the effectiveness of YAG-MSNs-RhD-6 powder in criminal investigations, we conducted simulations for different fingerprint scenarios. The results indicated that even after prolonged aging (up to 20 days), exposure to water, or high-temperature baking, the fingerprints remained clearly visible in the images. The detection of LFPs on various substrate surfaces exhibited high contrast, with the details of the fingerprints easily observable even after appropriate magnification. This study opens a new path for green light- and near-infrared light-induced up/down-conversion dual-channel composites for optical applications.

Aggregation-induced emission luminogens for latent fingerprint detection.

For over a century, fingerprints have served as a pivotal tool for identification of individuals owing to their enduring characteristics and easily apparent features, particularly in the realm of criminal investigations. Latent fingerprints (LFPs) are "invisible fingerprints" that are most commonly available at crime scenes and require a rapid, selective, sensitive, and convenient method for detection. However, existing fingerprint development techniques harbour limitations, prompting the exploration of novel approaches that prioritize investigator safety and environmental sustainability. Leveraging the unique photophysical properties of aggregation-induced emission luminogens (AIEgens) has emerged as a promising strategy for on-site analysis of LFP visualization. In this highlight, we have presented a comparative analysis of various AIEgens (organic compounds, metal complexes, nanoparticles, and polymers) for the development and detection of LFPs. Through this examination, insights into the efficiency and potential applications of AIE-based fingerprint development techniques are provided. In addition, several strategies have been proposed for circumventing the limitations of existing AIEgens. We hope that this highlight article will encourage more researchers to investigate AIEgens in LFP detection, contributing to forensic science.

Lipidomics in forensic science: a comprehensive review of applications in drugs, alcohol, latent fingermarks, fire debris, and seafood authentication.

Forensic science, an interdisciplinary field encompassing the collection, examination, and presentation of evidence in legal proceedings, has recently embraced lipidomics as a valuable tool. Lipidomics, a subfield of metabolomics, specializes in the analysis of lipid structures and functions, offering insights into biological processes that can aid forensic investigations. While not a substitute for DNA analysis in personal identification, lipidomics complements this technique by focusing on small biological molecules, with distinct sample requirements. This review comprehensively explores the current applications of lipidomics in forensic science. The review commences with an introduction to the concept and historical background of lipidomics, subsequently delving into its utilization in diverse areas such as drug analysis, ethyl alcohol and substitute assessment, latent fingermark detection, fire debris analysis, and seafood authentication. By showcasing the various biological materials and methods employed, this review underscores the potential of lipidomics as a powerful adjunct in forensic investigations.

Dual ligand based 3D Eu(iii) MOF as a multifunctional sensor for trace amounts of NACs, Cr3+ and Hg2+ in aqueous medium: synthesis, crystal structure and latent fingerprint detection

A novel 3D luminescent (MOF) named as [Eu(HPyzdc)(NITA)(H2O)]n (Cj-3) has been synthesized with isophthalic acid (H2NITA) and pyrazine based dicarboxylic acid (2,3-H2Pyzdc) via a solvothermal method.

Synthesis of phenol formaldehyde resin (PFR) based fluorescence resonance energy transfer (FRET) composites for double channel detection of latent fingerprints.

A reversible two-channel fluorescent nanocomposite with fluorescence resonance energy transfer (FRET) effect was designed for the development, analysis, and characterization of latent fingerprints (LFPs). For the construction of the FRET probe, a core of mesoporous silicas (MSNs) were used to encapsulate the organic dye rhodamine 6G (RhD-6) as an acceptor, while green-emitting monodisperse phenolic resin nanoparticles (PFR NPs) were selected as a donor. The up-conversion material (UC) of NaYF4:Yb,Er was synthesized using a simple hydrothermal method, and the MSNs-RhD-6/PFR (PRM) was electrostatically adsorbed onto the UC nanoparticles using a layer-by-layer method to obtain MSNs-RhD-6/PFR-UC (PMU). Compared to ordinary single-channel materials, PMU can be excited by different light sources (365 nm UV/980 nm laser) and its fluorescence can be reversibly switched between yellow and green, demonstrating excellent light reversibility. The PMU composites were successfully used to visualize and detect LFPs on various substrate surfaces using a simple powder coating method. Due to the existing FRET effect and dual-channel characteristics, this composite material displays excellent contrast, outperforming commercially available products for wider applicability. Even on complex backgrounds and after aging or washing treatments, it still clearly recognizes fingerprints in first-, second-, and third-level details, showing its great potential in latent fingerprint detection.

A difluoroboron compound with latent fingerprint detection and inkless writing based on aggregation-induced emission enhancement and mechanofluorochromic behavior

A pyridine-based difluoroboron compound with the TPA group displayed excellent AIEE activity and MFC behavior, which was applied for latent fingerprint detection and inkless writing.

High-contrast multi-surface imaging of latent fingerprints using color-tunable YOF:Tb3+,Eu3+ ultrafine nanophosphors with high quantum yield.

Visualization of latent fingerprints (LFPs) using conventional powders has faced challenges on multicolor surfaces. However, these challenges are addressed by the advent of fluorescent powders in LFP detection, and they have redefined the effectiveness of the powder dusting method. In this study, color-tunable YOF:Tb3+,Eu3+ nanophosphors were examined for LFP recognition and were evaluated for their practicality on different types of surfaces. Under 254 nm UV irradiation, the LFPs developed using these nanophosphors showed clear and distinct ridge patterns with level 1, 2, and 3 details. The ultrafine particles of these nanophosphors adhered to the ridge patterns and replicated the minutiae of the LFPs. Meanwhile, the variation of the Tb3+/Eu3+ ratio demonstrated multicolor fluorescence emission from the nanophosphors, which provided better contrast between the ridge patterns on complex surfaces. Furthermore, the high luminescence quantum yield of the nanophosphors ensured high-resolution fluorescence images of the LFPs with a well-defined pattern that was recognizable even without any microscope or sophisticated instrumentation.

Influence of annealing temperature on persistent luminescence in BaAl2O4:Eu2+/Eu3+ nanocrystals and its application for latent fingerprint detection.

The luminescent properties of europium (Eu) doped BaAl2O4 phosphors were strongly influenced by post-annealing temperatures for blue-green persistent luminescence and latent fingerprints (LFPs). The X-ray powder diffraction patterns of the BaAl2O4: 1 mol% Eu nanophosphor, annealed between 1000 and 1300 °C, indicated a hexagonal ferroelectric phase. The X-ray photoelectron spectroscopy (XPS) revealed that the Ba atoms occupied two different sites in the BaAl2O4. The XPS and photoluminescence (PL) results revealed the presence of Eu3+ and Eu2+ states. The Eu-doped BaAl2O4 showed the characteristic red emission of Eu3+ at 251 and 464 nm excitations, while excitations at 340 and 380 nm showed yellowish-green emission. Strong evidence of energy transfer between a charge transfer band and the different energy levels of Eu2+ and Eu3+ ions was obtained. The existence of the Cr ion impurity in the aluminates was confirmed with UV-VIS diffuse reflectance and PL spectroscopy. The present results suggested that and O''i defects have introduced electron and hole traps in the host that acted as luminescent centers for persistent luminescence. LFPs detection using BaAl2O3:Eu2+/Eu3+ phosphor showed an excellent marking agent for applications in forensic science.

Real-time visualization of latent fingermarks with level 3 details based on a solid state emissive organic fluorophore using the powder dusting method

A water-soluble organic fluorescent probe (Py-Pr-OH) is synthesized and applied for latent fingermarks (LFMs) detection via the powder dusting method. The amphiphilic probe provides LFM imaging with high contrast, and low background interference.

Synthesis, Characterization and Latent Fingerprints Detection of Novel Azo Dye Based on Curcumin and Its Pd (II) Complex

Synthesis, Characterization and Latent Fingerprints Detection of Novel Azo Dye Based on Curcumin and Its Pd (II) Complex

Nanoarchitectonics of WLC-H3PO4–MnFe2O3 nanocomposite for latent fingerprint detection

Carbon-based material powders have been applied in fingerprints development. However, sustaining fluorescence in solid substances remains difficult due to the severe emission suppression of carbon-based compounds in solid-state materials. This study is the first to report on the use of activated wool char coated on manganese-doped iron oxide nanoparticle (WLC-H3PO4–MnFe2O3) as a novel nanocomposite (nCOM) for latent fingerprint (LAFPs) detection via the powder dusting approach. Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Scanning Electron Microscope (SEM), Energy-Dispersive X-ray Spectrometry (EDS), and Transmission Electron Microscopy (TEM), XPS (X-ray photoelectron spectroscopy) were used to analyze this nanocomposite. The nanocomposite produced good LAFP pictures on non-porous substrates such as aluminium foil and aluminium sheets. Moreover, this nanocomposite could be utilized as a labeling agent and could aid in the detection of LFP under visible light by providing distinct readability ridges and high-contrast fingerprint pictures.

Fluorescent Materials for Latent Fingerprint Detection

Abstract: This review provides a comprehensive examination of the application of fluorescence materials for the detection of latent fingerprints in forensic sciences. Traditional methods like powder dusting, cyanoacrylate fuming, chemical methods, and small particle reagent techniques have shown limitations due to issues like low contrast, sensitivity, selectivity, and high toxicity. To overcome these drawbacks, recent focus has shifted towards using fluorescent materials, owing to their unique optical and chemical properties. This review underscores the importance of latent fingerprint development employing metal nanoparticles, semiconductor nanoparticles, and organic fluorescence compounds. These advanced materials not only provide heightened contrast, sensitivity, and selectivity compared to traditional methods but also manifest diminished toxicity. In essence, the review delivers a methodical survey of these pioneering techniques.

Latent fingerprint detection using fluorescent powder dusting technique

This study examined the use of fluorescent powder in detecting latent fingerprints through the dusting method. Five colors of fluorescent powder (orange, green, blue, green-yellow, and red) were applied to photo papers of six colors (green, red, blue, yellow, white, and black). The fluorescence of latent fingerprints was detected using various light sources including UV LED, blue LED, green LED, red LED, warm white, and cold white. The spectra of the light source and the fluorescence intensity of the dusting powder were analyzed to determine their influence on the appearance of latent fingerprints. The fingerprint images were analyzed by counting the number of important points that are more than 7 points, which indicates visible fingerprints. The results showed that the fluorescence of the powder, background, and light source affected the appearance of the fingerprints. When the color of the fluorescent powder matched the color of the light source, the fingerprints were clearly visible. However, if the background color matched the light source, the fingerprints were not visible. When fluorescent powder was dusted on a dark or non-fluorescent background, fingerprints were visible under all light sources. This study suggests that selecting the appropriate color of fluorescent powder and background is crucial for the detection of latent fingerprints using the dusting method.

Aggregation-induced phosphorescence emission-active heteroleptic Ir(III) complexes: Synthesis, photophysics, and latent fingerprint detection applications

Three heteroleptic Ir(III) complexes (Ir-TPA, Ir-CzPh and Ir-PhCz) with different electron-donating aryl groups on C^N ligands were synthesized. Their optical properties were systematically investigated by spectroscopic methods and theoretical calculations to elucidate the effects of introducing different electron-donating groups on their triplet excited state properties. All three complexes possess aggregation-induced phosphorescence emission (AIPE) behaviors. Critically, the relationship between the size of organic ligands and AIPE behaviors for these complexes has been characterized. Their significant AIPE properties predicted that they could be used as efficient latent fingerprint (LFP) developers. Rapid (within 10 s) incubation in Ir(III) complex solution produced high-resolution, naked-eye visible and mobile-photographable LFP images, which could provide fast, reproducible and identifiable analyses of level 3 details for LFPs accurately. In addition, complex Ir-PhCz shows the best imaging of the LFP due to its green light emission and high quantum yield (24.5 %) in solid state. This rapid and practical LFP visualization methodology based on AIPE developers could provide a reliable solution for LFPs detection and investigations in actual scenarios.

One-pot synthesis of versatile sphere-like nano adsorbent MnAl2O4 (MAO): an optical and magnetic material for efficient fluoride removal and latent finger print detection.

Spherically shaped trimetallic MnAl2O4 (MAO) nanoadsorbent was prepared in an one-pot synthesis process for the removal of excess fluoride from water. The adsorbent was characterized by thermogravimetric analysis (TGA), X-ray diffraction study (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), etc. The adsorption property for fluoride on the MAO was analyzed by batch experiments varying the adsorbent dose, pH, contact time, and initial fluoride concentration. The results showed that the fluoride uptake behavior of the samples could precisely be fitted by the Freundlich model, and the maximum adsorption capacity was estimated to be 39.21mg/g at room temperature. The pseudo-second-order models accurately described the adsorption kinetics data. The regenerated sample showed excellent reusability along with high removal capacity on real water sample also. The underlying fluoride adsorption mechanism via ion-exchange and electrostatic interaction was established from X-ray photoelectron spectroscopy (XPS) and zeta potential studies. The sample showed excellent luminescence with blue emission with a band gap of 2.6eV. The materials also showed good elastic behavior exhibiting the Poisson's ratio (σ) 0.32 and excellent latent figure print detection capacity distinguishing the clearly the ridge and furrow regions under UV light. The magnetic behavior was also found to be in long range with antiferromagnetic characteristics.

Unveiling Hidden Prints: Optically stimulated luminescence for latent fingerprint detection

Fluorescent lighting and optical techniques have been widely utilized to enhance the detection of latent fingerprints. However, the development of new techniques is imperative to expand the range of surfaces from which latent fingerprints can be detected. When relying on traditional methods, fingerprint evidence can remain undetected or even disregarded due to insufficient detection and limited detail, especially when dealing with a luminescent background.In this study, we propose the utilization of optically stimulated luminescence (OSL) applied to a Ba2SiO4 matrix, co-doped with Eu2+ and Dy3+, as a powerful method for visualizing latent fingerprints on various surfaces, including thin plastic bags, rigid duct tape, thin aluminum foil, and glass slices. This technique effectively eliminates any luminescent background and significantly enhances optical imaging.This represents the first successful application of OSL in the development of latent fingerprints, thus paving the way for more efficient and effective forensic techniques in the future.

Investigating the influence of mono-, di-, and trivalent co-dopants (Li+, Na+, K+, Ca2+, Bi3+) on the photoluminescent properties and their prospective role in data security applications for SrAl2O4:Tb3+ nanophosphors synthesized via an eco-friendly combustion method

Nanostructured SrAl2O4:Tb3+/M (M = Li+, Na+, K+, Ca2+, Bi3+) green nanophosphors (NPs) were synthesized through an environmentally friendly combustion process, employing Areca nut (A.N) as a sustainable fuel source. Alkali metal co-dopants were introduced to optimize luminescent intensity and assess their suitability for data security applications. Photoluminescence (PL) intensity increased with rising Tb3+ concentrations (1–5 mol %) until reaching a maximum at 3 mol %, after which quenching occurred. The phenomenon of Tb3+ concentration quenching at 3 mol % was explained using the Van Uitert equation, which accounts for dipole–dipole interactions. To enhance luminescence efficiency, various metal ions, including Li+, Na+, K+, Ca2+, and Bi3+, were explored. Notably, SrAl2O4:Tb3+ (SAO:Tb3+) co-doped with Li+ ions exhibited the highest PL intensity, surpassing that of Tb3+ by a factor of 41. The estimated CIE value for green emission are x = 0.3541 and y = 0.5562. It is observed that the CIE coordinates of Tb3+ activated SAO NPs are situated in the green region. The CCT value of SAO:Tb3+/Li+ was found to be 5117 K, which is useful for cool LEDs. The Li+ doped samples proved exceptionally effective in latent fingerprints (LFPs) detection, revealing level I-III ridge features crucial for personal identification. Under NUV light, the PDMS wrapping of the SAO:Tb3+/Li+ NPs accomplished a green glow. Based on the results, SAO:Tb3+/Li+ green-emitting phosphors is a promising material for white LEDs, optical temperature sensors, and flexible display applications. This comprehensive study underscores the outstanding multifunctional potential of Li+ co-dopants among the various ions considered.

Transforming human hair fibers into carbon dots: Utilization in flexible films, fingerprint detection, counterfeit prevention and Fe3+ detection

Creating environmentally-friendly fluorescent carbon quantum dots (HCQDs) from human hair is a straightforward process with versatile applications. These HCQDs, derived from non-toxic hair, are produced through a one-step microwave (MW) method and have gained increasing attention due to their exceptional properties. Despite the availability of various advanced HCQDs, their full potential remains untapped. Thanks to their remarkable optical characteristics, HCQDs serve as highly sensitive nano-probe agents for the fluorometric measurement of Fe3+ ions. The fluorescence (FL) intensity of the nano-probe exhibits a linear correlation with Fe3+ ion concentration ranging from 0 to 50 μM, boasting a limit of detection (LoD) of approximately 0.13 μM. This sensitivity is achieved through resonance energy/electron transfer-induced FL quenching. Remarkably, carbon dots (CDs) obtained from human hair function as ink-free patterned substrates, making them ideal for printing and the nondestructive collection and detection of latent fingerprints (LFPs). Immersing LFPs in HCQDs@poly(vinyl alcohol) (HCQDs@PVA) solution yields flexible, transparent films with consistent luminescent LFPs and clear ridge features for accurate personal identification. Importantly, this technique allows for the lifting and identification of long-term exposed LFPs from various surfaces without causing any damage. The segregation of HCQDs within the polymer matrix during film formation is the mechanism responsible for LFP collection and visualization. Overall, HCQDs@PVA composites exhibit outstanding performance, suitable for applications in fluorescent patterns, flat panel displays, LFP analysis, and anti-counterfeiting (AC) labeling.

Designing energy transfer-based color-tunable, information-encrypting, luminous hydro-gels, and latent fingerprint detection systems using BaLa2ZnO5:Tb3+, Bi3+ nanophosphors

Synthesizing cost-effective blue-green emitting BaLa2ZnO5:Tb3+, Bi3+ nanophosphors (BLZO:Tb3+, Bi3+ NPs) through an eco-friendly urea-aided combustion method. Thorough examination of phase purity, structure, surface characteristics, and luminescent properties of the resulting products reveals a robust blue-green emission linked to the 5D4 → 7F5 transition of Tb3+ under 365 nm UV excitation, as well as evident energy transfer from Bi3+ to Tb3+ within the co-doped BLZO, discussed in detail. Optimal doping concentrations are determined to be 5 mol% for Tb3+ and 0.3 mol% for Bi3+ in BLZO phosphor, with non-radiative transition mechanisms explaining concentration quenching. BLZO:Tb3+ NPs emits green light, while co-doping with Bi3+ shifted to the blue-green region. The optimized phosphor is employed for latent fingerprint (LFP) development on porous, semi-porous, and non-porous surfaces, with clear visualization under 365 nm UV light. The generated fingerprints (FPs) display level I–III ridge features with exceptional sensitivity, selectivity, and contrast. The luminescent hydro-gels exhibit outstanding photo-stability, chemical stability, and long-term durability, making them ideal for anti-counterfeiting (AC) applications. Furthermore, BLZO:Tb3+, Bi3+ NPs demonstrate the ability to mitigate oxidative stress and thrombosis, evidenced by their DPPH scavenging activity and their capacity to normalize stress indicators in Red Blood Cells (RBC) exposed to NaNO2-induced oxidative stress. These NPs also reduce ADP-induced platelet aggregation. Collectively, these results highlight the effective utilization of the optimized phosphor in display devices, advanced forensics, anti-counterfeiting measures, and biomedical applications.