简单而非破坏性的方法,以访问和处理覆盖滑动的幻灯片上的材料
Natalia Pedraza1, Michael A Marciano1
1Forensic & National Security Sciences Institute, Syracuse University, Syracuse, New York, USA.
Journal of forensic sciences
|May 15, 2025
概括
调查人员现在可以安全地访问旧幻灯片上的法医证据. 一种新的,简单的方法可以在不损坏毛发和纤维等微妙样本的情况下去除覆盖,改善了对性侵犯证据和尸检幻灯片的分析.
科学领域:
- 法医科学 法医科学 法医科学
- 显微镜的使用方法
- 收集证据 收集证据
背景情况:
- 法医证据往往有限,需要对档案幻灯片等非最佳来源进行分析.
- 来自性侵犯证据包,尸检和医院的幻灯片包含在安装介质中被困的有价值的物质证据 (毛发,细胞,纤维).
- 传统的覆盖去除方法是危险的,使用危险的溶剂和可能危害样品.
研究的目的:
- 开发一种新的,安全的,非破坏性的方法来获取幻灯片绑定的法医证据.
- 改进从具有挑战性的来源获得的痕迹证据的分析.
- 为了使以前无法访问的材料能够使用新的,更敏感的分析技术.
主要方法:
- 一种新的技术,利用潮湿的环境,逐渐将安装介质与盖子分开.
- 将透明的指甲油涂在盖子上,以确保安全,无裂纹的去除.
- 在不同年龄 (6+年) 的幻灯片上进行测试,使用不同的安装介质.
主要成果:
- 该方法成功地去除了100%的被测试的盖片.
- 这个过程很简单,安全,对底层的物质证据没有破坏性.
- 保存的样本可以通过先进的技术进行下游分析.
结论:
- 这种新方法可以安全有效地访问以前被困在幻灯片上的关键法医证据.
- 它克服了传统危险技术的局限性.
- 它增强了从性侵犯工具包和档案来源的痕迹证据的详细分析的潜力.
相关概念视频
Fixation and Sectioning
4.1K
Two basic types of preparation are used to visualize specimens with a light microscope: wet mounts and fixed specimens.
The simplest type of preparation is the wet mount, in which the specimen is placed in a drop of liquid on the slide. A liquid specimen can be directly deposited on the slide using a dropper. Solid specimens, such as skin scraping, can be placed on the slide before adding a drop of liquid to prepare the wet mount. Sometimes the liquid is simply water, but stains are often added...
The simplest type of preparation is the wet mount, in which the specimen is placed in a drop of liquid on the slide. A liquid specimen can be directly deposited on the slide using a dropper. Solid specimens, such as skin scraping, can be placed on the slide before adding a drop of liquid to prepare the wet mount. Sometimes the liquid is simply water, but stains are often added...
4.1K
Overview of Microscopy Techniques
9.6K
The early pioneers of microscopy opened a window into the invisible world of microorganisms. In 1830, Joseph Jackson Lister created an essentially modern light microscope. The 20th century saw the development of microscopes that leveraged nonvisible light, such as fluorescence microscopy that uses an ultraviolet light source and electron microscopy that uses short-wavelength electron beams. These advances significantly improved magnification, image resolution, and contrast. By comparison, the...
9.6K
Confocal Fluorescence Microscopy
12.8K
Confocal microscopy is an advanced microscopic technique. The prime advantage of the confocal microscope over other microscopy techniques is its ability to block the out-of-focus light from the illuminated samples using pinholes. It is widely used with fluorescence optics to obtain high-resolution, sharp contrast images. Unlike optical microscopes, confocal microscopes use a focused beam of light laser to scan the entire sample surface at different z-planes. These microscopes are, therefore,...
12.8K
Preparation of Samples for Electron Microscopy
5.3K
To be visualized by an electron microscope, either transmission or scanning, biological samples need to be fixed (stabilized) so the electron beam does not destroy them and dried thoroughly (desiccated/dehydrated) so the vacuum does not affect them. Fixation needs to be done as quickly as possible because the sample properties will start changing as soon as it is removed from its natural environment. For example, in a tissue sample, the oxygen levels begin decreasing, causing an altered...
5.3K


