用深紫外线,近紫外线和可见刺激进行光显微镜,用于In Situ检测微生物
Noel Case1, Nikki Johnston1, Jay Nadeau1
1Department of Physics, Portland State University, Portland, Oregon, USA.
Astrobiology
|March 20, 2024
概括
我们开发了一种负担得起的光显微镜,使用深紫外线 (DUV) 激发来检测矿物中的微生物. 这种方法最大限度地减少了矿物自光,并提高了标记和未标记细菌的检测.
科学领域:
- 微生物学 微生物学
- 显微镜的使用方法
- 频谱学是一种光谱学.
背景情况:
- 在矿物基质中检测微生物对于环境和天体生物学研究至关重要.
- 传统的光显微镜可能受到矿物自光和需要专门设备的限制.
- 发光二极管 (LED) 激发为光显微镜提供了一种具有成本效益和多功能性的替代方案.
研究的目的:
- 设计一种简单,廉价的光显微镜,用于检测矿物基质中的标记和未标记的微生物.
- 评估与近紫外线和可见激发相比,深紫外线 (DUV) 激发对微生物检测的有效性.
- 优化照明几何形状,以提高矿物样本的信号噪声比.
主要方法:
- 使用LED激发的光显微镜的开发,特别是深紫外线 (DUV) <280nm.
- 实施斜照明几何学来减少矿物自光.
- 对DUV,近紫外线 (365nm) 和可见激发源进行微生物检测的比较分析.
- 细菌,常见染料和矿物自光的辐射光谱的表征.
主要成果:
- 与近紫外线激发相比,DUV激发 (<280nm) 有效地减少了矿物自光.
- 在DUV激发下,无色素细菌在近紫外线 (蛋白质) 和蓝绿范围 (黄素/NADH) 中表现出明显的排放峰值.
- DUV刺激不适合检测蓝藻细菌中的叶绿素,但可见刺激可以区分红色染料和叶绿素自光.
- 结合DUV和可见/近紫外线激发策略,可以全面检测各种微生物.
结论:
- 一个简单的,廉价的光显微镜与DUV LED激发是有效的检测微生物在矿物质基板.
- 在降低矿物自光和检测特定细菌成分方面,DUV激发具有优势.
- 建议将DUV与可见或近紫外线激发配对,以彻底检测各种微生物,包括蓝藻细菌.
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