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1.
Lawsone is a 2‐substituted‐1,4‐naphthoquinone derivative, which has been proposed as an alternative to the reagents currently used for fingermark detection on porous surfaces. 2‐substituted‐anthraquinones, which contain an additional conjugated benzene ring, have a similar chemical structure to that of lawsone. In this study, a new series of 2‐substituted‐1,4‐naphthoquinones and 2‐substituted‐1,4‐anthraquinones were synthesized and completely characterized by1H NMR,13C NMR, IR, and HPLC‐TOF/MS analyses. All newly synthesized 2‐substituted‐1,4‐quinones were investigated for their ability to develop latent fingermarks on porous surfaces, and this ability was compared with that of lawsone. Each fingermark developed was graded using an established method; thus, quantitative data were attributed to each fingermark. It has been demonstrated that the 1,4 ‐ quinones react with amino acids present in latent fingermarks on selected paper surfaces to produce faint yellow‐orange impressions, which exhibit strong photoluminescence when illuminated with a forensic light source at 440 nm and observed through a red filter. None of the compounds caused background darkening. The results obtained were generally similar to those of lawsone, however, 8‐dibromo‐2‐(propylamino)naphthalene‐1,4‐dione and 5,8‐dibromo‐2‐(propylthio)naphthalene‐1,4‐dione yielded better results for copier paper and colored (blue) copier paper used in this analysis. To the best of our knowledge, this is the first study to examine the role of 1,4‐anthraquinone derivatives as potential fingermark development reagents. The results indicate that 1,4‐quinones have a potential to be used as reagents for enhancement of latent fingermarks.  相似文献   

2.
Conventional development of latent fingerprints is compromised when the prints are decomposed by extreme temperatures, such as those encountered when a weapon cartridge is fired, an improvised explosive device is detonated, and/or in arson cases. Understanding how these extreme temperatures alter the chemical and physical properties of latent fingerprint residue could aid in the discovery of a reagent that could effectively develop these decomposed fingerprints. To mimic scenarios where fingerprints may be exposed to high heat conditions, standards of the five most abundant amino acids in fingerprint residue as well as extracted fingerprint residue were pyrolized under controlled conditions. Compounds identified as pyrolytic decomposition products were 3,6-dimethylpiperazine-2,5-dione (from alanine), maleimide, and 2,5-furandione (from aspartic acid). The pyrograms and selected ion traces show these products to hold promise as indicators of decomposed fingerprint residues and, therefore, may serve as good candidate substrates for a developing reagent.  相似文献   

3.
《Science & justice》2022,62(3):365-376
Forensic recovery from fired ammunition casings remains one of the most challenging tasks during high-profile investigations. Often, the decision must be made between screening for DNA or fingerprints, and, in doing so, the impact these processes will have on the examination of ballistic markings imparted on the ammunition from the firearm itself. Traditionally, fingermark enhancement processes have yielded low success rates in their efforts to identify suspects by enhancing friction ridge detail left on the cartridge casings. Moreover, the enhancement methods utilised may often induce detrimental physical changes to the casing(s), rendering them unsuitable for subsequent ballistics (marking) examination. Recently, new technology has been shown to increase the success rate of fingermark recovery from fired ammunition, and the growing adoption of such innovation means that new challenges are encountered to maximise evidence recovery and streamline forensic workflows. One such example arises from the potential obscuration of the ammunition headstamp area during such treatments. Accordingly, this study outlines the preliminary investigations and developments of a polymer mask substrate that serves to protect the headstamp of fired ammunition casings during relevant fingermark enhancement processes. The technique also has the capacity to be used as a surface protection device to eliminate unwanted chemical deposition across other areas of interest and evidence types.  相似文献   

4.
A critical investigation of 5-methylthioninhydrin (5MTN) is presented as a 'dual action' formulation component for the development of latent finger marks on paper substrates. Preparation of a dual action reagent was performed by combining proportions of 5MTN and zinc chloride (ZnCl(2)) in a pre-mixed solution. Developed prints (deposited on filter paper substrates) could be subsequently visualised in both colour and fluorescence modes. Finger mark quality was graded using a quartered print approach for a number of reagent compositions to deliver an optimised formulation recipe. To fully appraise 5MTN in comparison to currently employed chemistries, this reagent was evaluated against three alternative amino acid selective reagents, ninhydrin, 1,8-diazafluorenone (DFO) and 1,2-indandione/ZnCl(2). Six common paper types were used for this purpose and split depletion finger marks from six donors were collected. Finger mark sets were also left for two days or two weeks to show the effect of ageing on development quality. For the first time, it was shown that 5MTN/ZnCl(2) is effective as a 'dual action' reagent under the United Kingdom climate conditions. However, results presented herein show that the existing recommended chemistries and the 1,2 indandione/ZnCl(2) process are all more effective than this new latent finger mark enhancement reagent. In a preliminary sequencing study, we show the effectiveness of the existing DFO-ninhydrin sequence over dual action reagents.  相似文献   

5.
Anecdotal evidence from forensic practitioners and studies conducted under controlled conditions have indicated that the reaction between 1,2-indanedione and the amino acids present in latent fingermark deposits is highly susceptible to ambient humidity. The addition of catalytic amounts of zinc chloride to the 1,2-indanedione working solution--usually in the order of 1:25 to 1:4 molar ratio (indanedione:zinc)--significantly improves the colour and luminescence of fingermarks treated under dry conditions but appears to have a negligible effect on fingermarks treated in humid environments. The results presented in this paper confirmed that zinc(II) ions added to the 1,2-indanedione working solution act as a Lewis acid catalyst, stabilising a key intermediate during a rate-limiting hydrolysis step. Furthermore, studying the reaction using a chromatography-grade cellulose substrate method previously reported confirmed that cellulose substrates play a major role in facilitating the indanedione-amino acid reaction by acting as a surface catalyst in the early stages of the reaction and by directing the formation of the desired luminescent product (Joullié's Pink).  相似文献   

6.
The usefulness of a number of silver salts as alternatives to silver nitrate for the detection of fingerprints is discussed.  相似文献   

7.
A study into the modification of 1,8-diazafluoren-9-one (DFO) formulations by the additions of metal salts into the working solution is reported. Similar additions have been found to increase the fluorescence of marks developed using other amino acid reagents including 1,2-indandione and the ninhydrin analogue 5-methylthioninhydrin. It was found that adding zinc chloride to give a 1:1 ratio of zinc ions:DFO molecules gave optimum fluorescence, and improvements in performance over the standard DFO formulation were achieved. Attempts to produce equivalent formulations with iron, nickel and palladium chlorides were unsuccessful. In a comparative trial with a 1,2-indandione-zinc formulation on brown paper and cardboard substrates, 1,2-indandione-zinc gave superior results and it was decided to focus further research on this reagent instead of DFO-zinc.  相似文献   

8.
In this investigation 400 bilateral rolled fingerprints of Punjabi Jat males have been examined for the determination of the hand from single digit fingerprint from whorl patterns. Direction of the flow of the apex ridges, rotation of centrally circular ridges, angles between the core and the delta, ridge tracing, ridge counting and the position of the perpendiculars drawn between the delta and the core are useful for establishing in most of the cases the hand and finger involved from the fingers having whorl pattern.  相似文献   

9.
Cyanoacrylate fuming is one of the most common techniques employed for the detection of latent fingermarks on non-porous surfaces such as plastic and glass. The technique is generally applied by exposing items of interest to the vapours generated by heating a suitable quantity of commercial cyanoacrylate adhesive. In this study, the potential for highly toxic hydrogen cyanide (HCN) to be generated from the overheating of cyanoacrylate was investigated. Two commercial cyanoacrylate adhesives and two quantitative methods for the determination of HCN were employed: (i) the sodium picrate method; and (ii) the picrate-resorcinol method. (13)C nuclear magnetic resonance (NMR) analysis was used to confirm the presence of cyanide. In addition, the thermal decomposition of cyanoacrylate was studied using simultaneous thermogravimetric and differential thermal analysis (TGA-DTA). It was determined that detectable and quantifiable amounts of HCN were generated from the thermal decomposition of cyanoacrylate monomer and polymer at temperatures as low as 200 °C. Using an optimised picrate-resorcinol method, it was shown that around 10 μg of HCN could be generated from the heating of 1g of cyanoacrylate monomer at 200 °C. For one of the adhesives tested, this increased to above 100 μg of HCN when 1g of cyanoacrylate monomer was heated at 280 °C. Recommendations are provided that, if followed, should ensure that the cyanoacrylate fuming process can be safely applied with minimal risk to the operator.  相似文献   

10.
11.
Thirteen ninhydrin analogues have been synthesized and evaluated as amino acid-specific fingerprint reagents. All of the ninhydrin analogues tested developed latent fingerprints on paper surfaces in a manner similar to ninhydrin itself. The photoluminescent enhancement of prints developed with each reagent was assessed after treatment with zinc(II) or cadmium(II). The results obtained have been related to the effects of substitution on the ninhydrin skeleton. Two compounds in particular, 5-methoxyninhydrin and benzo[f]ninhydrin, were shown to offer operational advantages over ninhydrin on a number of difficult surfaces. Prints developed with either reagent show stronger room temperature luminescence after zinc(II) or cadmium(II) treatment in comparison with equivalent prints developed with ninhydrin. Both 5-methoxyninhydrin and benzo[f]ninhydrin have been shown to be effective on surfaces where background luminescence precludes the successful enhancement of ninhydrin-developed prints.  相似文献   

12.
Most footwear marks made in blood on a surface such as fabric tend to be enhanced in situ rather than physically recovered using a lifting technique prior to enhancement. This work reports on the use of an alginate material to recover the impressed footwear marks made in blood and deposited on a range of fabric types and colours. The lifted marks were then enhanced using acid black 1 and leuco crystal violet with excellent results.This presents a new method for the lifting and recovery of blood impressions in situ from crime scene followed by subsequent mark enhancement of the lifted impression.  相似文献   

13.
《Science & justice》2014,54(3):185-191
Recent studies have reported the use of alginate in the lifting and subsequent enhancement of footwear marks in blood. A study was set up to assess the use of such a method in the treatment of fingermarks in blood on a variety of porous, non-porous and semi-porous surfaces. Other variables included ageing of the fingermarks in blood and the application of chemicals prior to or post-alginate lifting. All different variations were compared to direct chemical treatment of the substrate. The results demonstrated that alginate is not compatible with certain substrates (e.g. glass and tile). On substrates that were compatible with alginate (e.g. fabric and paper), the enhanced fingermarks on the alginate cast and the enhanced fingermarks on the post-alginate substrates appeared, overall, inferior compared to direct chemical enhancement without the use of alginate. A further variation using water-based protein stains directly mixed with the alginate appeared to provide enhancement directly on the substrate as well as simultaneous lifting and enhancing the fingermarks in blood on the alginate cast.  相似文献   

14.
Silicon dioxide-based nanocomposites have shown great potential in novel chemical and biological sensor development due to their large loading capacity and high surface area to volume ratio for trapping molecular complexes of various sizes. However, their potential applications in forensic science, latent fingerprint detection in particular, were still unclear. In this study, we have succeeded in trapping the highly fluorescent and photo-stable Eu3+ metal ions/sensitizer complex in silicon dioxide-based nanocomposites, doped xerogels, using the sol-gel method. We have tested the spectroscopic properties of Eu3+ in several combinations of rare earth sensitizers and different derivatives of silicon dioxide nanoporous templates. Our results indicated that the use of 1,10-phenanthroline (OP) sensitizer in tetraethoxysilane (TEOS) template provides the best fluorescently doped xerogels applicable for latent fingerprint detections on various forensic relevant materials, including metal foil, glass, plastic, colored paper, and a green tree leaf. The fabrication procedure, UV/vis and fluorescence characterizations, and fingerprint labeling results of these new Eu3+/OP/TEOS nanocomposites are presented in this exploratory study.  相似文献   

15.
16.
Food  Drug Administration  HHS 《Federal register》2004,69(226):68254-68255
The Food and Drug Administration (FDA) is classifying newborn screening test systems for amino acids, free carnitine, and acylcarnitines using tandem mass spectrometry into class II (special controls). The special control that will apply to the device is the guidance document entitled "Class II Special Controls Guidance Document: Newborn Screening Test Systems for Amino Acids, Free Carnitine, and Acylcarnitines Using Tandem Mass Spectrometry." The agency is taking this action in response to a petition submitted under the Federal Food, Drug, and Cosmetic Act (the act) as amended by the Medical Device Amendments of 1976, the Safe Medical Devices Act of 1990, the Food and Drug Administration Modernization Act of 1997, and the Medical Device User Fee and Modernization Act of 2002. The agency is classifying the device into class II (special controls) in order to provide a reasonable assurance of safety and effectiveness of the device. Elsewhere in this issue of the Federal Register, FDA is publishing a notice of availability of a guidance document that is the special control for this device.  相似文献   

17.
The rise of fentanyl and fentanyl analogs in the drug supply pose serious threats to public health. Much of these compounds enter the United States through shipping routes. Here we provide a method for fentanyl screening and analysis that utilizes pressure-sensitive adhesive (PSA) lined paper to recover drug residues from parcel-related surfaces. The paper used is commercially available repositionable notes (also called post-it or sticky notes). From this paper, mass spectra were obtained by paper spray-mass spectrometry (PS-MS), where PSA paper served as both a sampling and analysis substrate. Seven fentanyl-related compounds were analyzed: fentanyl, 4-anilino-N-phenethylpiperidine (4-ANPP), N,1-diphenethyl-N-phenylpiperidin-4-amine (phenethyl-4-ANPP), valerylfentanyl, 4-fluoroisobutyrylfentanyl (4-FIBF), carfentanil, and p-fluorofentanyl. These compounds were recovered by PSA paper and identified by PS-MS from packaging tape and plastic at 50 ng and from cardboard and shipping labels at 100 ng. The impact of cutting agents on PS-MS analysis of fentanyl analogs was explored. No trends of analyte suppression were found at high concentrations of the cutting agents caffeine, diphenhydramine, and lidocaine when recovered from surfaces. A cartridge that required no precise cutting of PSA paper prior to sampling or analysis was evaluated for use in PS-MS for fentanyl screening. Recovery and detection of fentanyl from plastic sheeting was demonstrated with this cut-free cartridge. The cut-free cartridge showed somewhat less consistency and lower analyte signal than the standard cartridge, but performance was suitable for potential screening applications. In combining PSA surface sampling with PS-MS for drug screening, both sampling and detection of fentanyl-related compounds is simple, rapid, and low-cost.  相似文献   

18.
《Federal register》1997,62(147):40996-41001
The Food and Drug Administration (FDA) is requesting written comments related to the advisability of revoking or amending the interim final rule that permitted the Commissioner of Food and Drugs (the Commissioner) to determine that obtaining informed consent from military personnel for the use of an investigational drug or biologic is not feasible in certain situations related to military combat. The agency is also soliciting written comments identifying the evidence needed to demonstrate safety and effectiveness for such investigational drugs that cannot ethically be tested on humans for purposes of determining their efficacy. FDA is seeking written comments from all interested groups, including, but not limited to: Consumers, patient groups, veterans and veteran groups, active-duty military personnel, organizations and departments, ethicists, scientists, researchers with particular expertise in this area, and health care professionals. The written comments are intended to provide FDA with information to help the agency in making policy decisions on the use of investigational products during military exigencies and the appropriate evidence needed to demonstrate safety and effectiveness for drug and biological products used in military or other exigencies when traditional human efficacy studies are not feasible.  相似文献   

19.
Efficacy of gel chromatography for purification of extracts from cadaveric material containing beta-adrenoblockers was shown in model tests. Distribution curves and chromatographic features of beta-adrenoblockers obtained on hydrophilic and lipophilic-hydrophilic Sephadex were studied.  相似文献   

20.
The authors have published elsewhere a quantitative method for assessing weight of evidence in the case where a finger mark from a crime scene is compared with a control print taken from a single finger of a suspect. The approach is based on the notion of calculating a likelihood ratio (LR) that addresses a pair of propositions relating to the single finger that was the origin of the crime mark. In practice, things are rather different because the crime mark will not just be compared with a single finger from a suspect but with a set of prints from all of his/her fingers; likewise, when the mark is compared with a database, this will consist of ten print records from random individuals. It is clear that "finger propositions" are not realistic in this situation and we show how our approach may be generalised to address a pair of propositions that relate to the person that made the crime mark. It often is the case that information is present at the crime scene that enables some inference to be drawn relating to which of the offender's ten fingers left a particular mark of interest. This kind of inference may profitably be drawn into the formal analysis. We illustrate our approach with an example.  相似文献   

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