茚三酮与DFO显现方法比较研究

茚三酮和DFO在显现渗透性客体上的汗潜手印时,显现原理、实验方法,以及实验结果均有不同.茚三酮法作为传统的渗透性客体汗潜指纹显现法,有其独特的优越性,但该法显现效果受客体背景影响大.DFO法适用客体范围广,可在重要现场手印提取中优先使用.在实际工作,可根据现场实际情况,使其优势互补,而更好地为现场勘查服务.     

Recovery of DNA and fingerprints from touched documents

This study investigated the various factors affecting DNA profiling from DNA recovered from fingerprints deposited on paper before and after fingerprint enhancement treatments. The DNeasy^® plant mini kit (QIAGEN^®) was found to improve DNA recovery from paper by over 150% compared with the QIAamp^® mini kit. A significant decrease in the amount of DNA recovered was observed following treatment with DFO and/or Ninhydrin. This decrease in yield did not have a comparably significant effect on the quality of the SGM Plus™ profiles. Furthermore, this study found that whilst certain paper types, such as newspaper, magazine and filter paper allowed for the good recovery of DNA, common office paper and white card, strongly interfered with the recovery of DNA resulting in poor quality profiles.     

DFO与IDO显现手印效果的比较研究

DFO显现法和IDO显现法,都是显现纸张等渗透性客体上的汗液手印的有效方法。但是,实验研究发现,复印纸、白信封纸、报纸和牛皮纸上的汗液手印,用IDO法显现效果都优于DFO法。IDO法不仅手印的显现率高,而且显出的手印纹线更加清晰,可鉴定率也明显高于DFO法。     

双面胶带上指印的显现方法研究

双面胶带是我们生活中常用的一种胶带,在许多案件中经常出现。本文主要研究双面胶带转印在纸张等渗透性客体上的手印来间接地显现双面胶带上的指印,从而认定作案的犯罪嫌疑人。     

京尼平序列显现手印方法研究

目的考察京尼平溶液显现手印的灵敏度,并探索DFO→京尼平→茚三酮方法联用显现纸张上潜在手印的效果。方法通过使用京尼平溶液对同一手印样本进行一次、两次和三次浸泡处理,考察浸泡次数是否会影响显现效果;通过对京尼平→茚三酮、茚三酮→京尼平,京尼平→DFO和DFO→京尼平方法的组合设计方案与每种方法的单独使用进行比较研究,考察序列显现方法对显出手印的影响。结果单用京尼平溶液对同一样本进行多次浸泡在自然光和荧光模式下都不会明显增强手印的显现效果,DFO方法先于京尼平、京尼平先于茚三酮使用都能起到增强手印纹线的效果。结论京尼平方法显现手印灵敏度较高,DFO→京尼平→茚三酮方法联用可以进一步提高手印的显出率。     

京尼平显现渗透性客体上潜在手印方法研究

目的介绍一种能够用来显现潜在手印的新型物质—京尼平。方法依据京尼平能和手印遗留物质中的氨基酸或蛋白质发生反应,生成一种有荧光效应的多聚体深蓝色物质,通过自然光或多波段光源下显现观察,并将其与传统的茚三酮、DFO显现进行比较。结果京尼平显现法的显现条件与茚三酮类似,其处理后的潜在手印既在自然光下可见又在多波段光源的激发下有荧光现象。结论京尼平显现法可用于渗透性客体上潜在手印的显现。     

硝酸银、茚三酮、DFO法显现纸张上指印的效果比较

目的为有效的提高纸张上汗潜手印的显现率。方法根据汗潜手印的显现原理,针对不同的纸张,分别运用硝酸银、茚三酮与DFO（1,8-二氮芴-9-酮）3种显现方法进行了实验,并对实验结果进行了分析比较。重点分析了这3种方法在显现不同纸张、不同遗留时间、不同汗液量的汗潜手印时的效果及其适用范围。结果为改善渗透性客体上的汗潜手印显现效果,提供科学的依据。     

Enhancement of ninhydrin- or DFO-treated latent fingerprints on thermal paper

A new method for enhancement of ninhydrin or 1,8-diazafluoren-9-one (DFO)-treated latent fingerprints on thermal paper will be described. Most thermosensitive surfaces of thermal paper become dark when treated with DFO or ninhydrin petroleum ether (NPB) solution. This effect minimizes contrast between the developed fingerprints and the background. The new method described reduces this dark staining without removing the thermosensitive layer and parts of the developed fingerprints, as occurs with acetone washing. Through the new method, the developed fingerprints appear in sharp lines and high contrast. Extensive tests were performed, leading to an optimized working solution, which charges the paper with a minimum of chemicals, is cheap, and enables a large quantity of papers to be treated in a short time. The working solution contains commercially available, nonvolatile, nitrogenous organic compounds and can be used like the application of NPB solution by dipping.     

Optimisation and evaluation of 1,2-indanedione for use as a fingermark reagent and its application to real samples

1,2-indanedione is an emerging fingermark reagent used on porous surfaces. The general consensus is that this reagent is at least as sensitive as DFO, with some research showing higher sensitivity for 1,2-indanedione as opposed to DFO. However, a number of discrepancies existed in the literature as to which formulation and which development procedure produces optimal results. This project set out to investigate the best formulation and development procedure under Australian conditions, encompassing all published recommendations as well as some novel approaches. 1,2-indanedione formulations were compared with respect to initial colour, fluorescence, concentration of reagent, acetic acid concentration, and the effect of different carrier solvents. Numerous development conditions were investigated, including a conventional oven, a heat press and humidity. Further enhancement using metal salt treatment and liquid nitrogen was also evaluated. The heat press set at 165 degrees C for 10s proved to give the best initial colour and most intense luminescence. Secondary metal salt treatment improved initial colour and luminescence. The Polilight, the VSC 2000, and the Condor Chemical Imaging macroscope have been used to detect the fingerprints developed with 1,2-indanedione on a variety of high- and low-quality porous and semi-porous surfaces, with impressive results overall. Laboratory and field tests were conducted to compare 1,2-indanedione with DFO and ninhydrin as well as to investigate the position of 1,2-indanedione in the sequence of reagents for fingermark detection on porous surfaces. Overall, 1,2-indanedione proved to be a viable alternative to traditional methods for the detection of fingermarks on porous surfaces, with more fingermarks being developed using this reagent on real samples than both DFO and ninhydrin and a combination of the two reagents.     

DFO、IDO显现纸张上汗液手印灵敏度比较研究

DFO、IDO显现法都是显现纸张等渗透性客体上汗液手印的有效方法。对这两种显现方法的灵敏度进行研究有利于实际应用时的正确选择。实验比较研究发现：不同客体、不同遗留时间及不同次数遗留的手印，IDO显现法的灵敏度都要高于DFO法。牛皮纸、报纸等客体上遗留时间较长、形成次数较多的汗液手印的显现，应优先考虑使用IDO显现法。