Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the etiologic agent of the COVID-19 pandemic. Although other diagnostic methods have been introduced, detection of viral genes on oro- and nasopharyngeal swabs by reverse-transcription real time-PCR (rRT-PCR) assays is still the gold standard. Efficient viral RNA extraction is a prerequisite for downstream performance of rRT-PCR assays. Currently, several automatic methods that include RNA extraction are available. However, due to the growing demand, a shortage in kit supplies could be experienced in several labs. For these reasons, the use of different commercial or in-house protocols for RNA extraction may increase the possibility to analyze high number of samples. Herein, we compared the efficiency of RNA extraction of three different commercial kits and an in-house extraction protocol using synthetic ssRNA standards of SARS-CoV-2 as well as in oro-nasopharyngeal swabs from six COVID-19-positive patients. It was concluded that tested commercial kits can be used with some modifications for the detection of the SARS-CoV-2 genome by rRT-PCR approaches, although with some differences in RNA yields. Conversely, EXTRAzol reagent was the less efficient due to the phase separation principle at the basis of RNA extraction. Overall, this study offers alternative suitable methods to manually extract RNA that can be taken into account for SARS-CoV-2 detection.

严重急性呼吸系统综合症冠状病毒2（SARS-CoV-2）是COVID-19大流行的病因。尽管已经引入了其他诊断方法，但是通过逆转录实时荧光定量PCR（rRT-PCR）分析检测口咽和鼻咽拭子上的病毒基因仍然是金标准。有效的病毒RNA提取是rRT-PCR分析下游性能的前提。当前，有几种自动方法，包括RNA提取。但是，由于需求的增长，一些实验室可能会遇到试剂盒供应短缺的情况。由于这些原因，使用不同的商业或内部协议进行RNA提取可能会增加分析大量样品的可能性。在这里 我们比较了三种不同商业试剂盒的RNA提取效率和使用SARS-CoV-2合成ssRNA标准品以及来自6名COVID-19阳性患者的鼻咽拭子的内部提取方案的效率。得出的结论是，经过测试的商业试剂盒可以进行一些修改，以通过rRT-PCR方法检测SARS-CoV-2基因组，尽管在RNA产量方面存在一些差异。相反，由于基于RNA提取的相分离原理，EXTRAzol试剂的效率较低。总体而言，这项研究提供了其他合适的方法来手动提取RNA，可以将其用于SARS-CoV-2检测。得出的结论是，经过测试的商业试剂盒可以进行一些修改，以通过rRT-PCR方法检测SARS-CoV-2基因组，尽管在RNA产量方面存在一些差异。相反，由于基于RNA提取的相分离原理，EXTRAzol试剂的效率较低。总体而言，这项研究提供了其他合适的方法来手动提取RNA，可以将其用于SARS-CoV-2检测。得出的结论是，经过测试的商业试剂盒可以进行一些修改，以通过rRT-PCR方法检测SARS-CoV-2基因组，尽管在RNA产量方面存在一些差异。相反，由于基于RNA提取的相分离原理，EXTRAzol试剂的效率较低。总体而言，这项研究提供了其他合适的方法来手动提取RNA，可以将其用于SARS-CoV-2检测。