四、总结与展望

MALDI-TOF MS是一种简单、快速、高通量和高效的微生物鉴定手段, 在临床样本直接检测方面较传统的鉴定方法具有更大的优势, 能显著降低样本检测的周转时间和成本, 但尚存在着一些不足之处, 主要表现在:(1)MALDI-TOF MS在检测和鉴定细菌方面的敏感性还不高, 不能直接鉴定患者血样本中的病原菌(细菌数量太少); (2)对于一些核糖体蛋白差异较小的细菌用其辨别有较大的困难; (3)目前的研究都有各自不同的操作过程, 在样本处理、质谱图采集和分析等方面没有统一的标准, 可能会影响分析结果在实验室内和实验室间的可重复性; (4)标准的鉴定参考图谱数据库尚不够完善, 需要进一步拓展; (5)对一些细胞壁难以破坏的细菌(如革兰阳性菌、酵母菌)和混合菌等的鉴定能力还不够高。但是相信随着更加有效的样本预处理方法、更加严格的检测过程控制和更高分辨率的图像处理技术的实现, MALDI-TOF MS用于直接检测临床样本中的微生物会有更广阔的前景。

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