Pipetting and concentration measurement of viscous ultra-high-molecular-weight (UHMW) DNA samples is challenging and often highly imprecise. Effective guidelines for handling UHMW samples are missing in the field. Herein, a simple and low-cost workflow is presented that enables accurate pipetting and reliable concentration measurement. Central to the workflow is the shearing of representative small aliquots of UHMW DNA samples to a fragment size <150 kb by vortexing them for 1 min with a glass bead in a round-bottomed 2-ml tube. Additionally, a solution is provided for accurate quantitation of high-molecular-weight DNA with fluorometric (Qubit [Thermo Fisher Scientific, MA, USA]) methods by using an appropriate genomic DNA standard, resulting in values that match spectrophotometric (Nanodrop [Thermo Fisher Scientific]) optical density readings.

中文翻译：

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一种对超高分子量 DNA 进行有效剪切和可靠浓度测量的简单方法。

粘性超高分子量 (UHMW) DNA 样品的移液和浓度测量具有挑战性，而且通常非常不精确。现场缺少处理 UHMW 样品的有效指南。在此，提出了一种简单且低成本的工作流程，可实现准确的移液和可靠的浓度测量。工作流程的核心是通过在圆底 2 毫升管中用玻璃珠涡旋 1 分钟，将具有代表性的小等分 UHMW DNA 样品剪切成小于 150 kb 的片段大小。此外，通过使用适当的基因组 DNA 标准，通过荧光（Qubit [Thermo Fisher Scientific，MA，USA]）方法准确定量高分子量 DNA 提供了一种解决方案，从而产生与分光光度法（Nanodrop [Thermo Fisher Scientific，MA，USA]）匹配的值科学]) 光密度读数。