Nx 48 viral na kit

Clinical whole blood samples were collected from patients infected with malarial parasites at the Korea University Guro Hospital from June 2000 to July 2017. All clinical samples were diagnosed by microscopic examination of Giemsa-stained blood smears and in-house PCR tests at the Korea University Guro Hospital. In total, 208 whole blood specimens were used in the present study, including 118 positive specimens of four types of malaria (61 P. falciparum, 54 P. vivax, 2 P. malariae, and 1 P. ovale) and 90 negative specimens. DNA extraction from the 208 whole blood samples was performed using the NX-48 Viral NA Kit, with a Nextractor NX-48 system (Genolution, Seoul, Korea), according to the manufacturer’s instructions. DNA was stored at −50 °C. All tests were performed in a blinded manner, with the operator unaware of any previous test results. The study was conducted in accordance with the guidelines of the Declaration of Helsinki and was approved by the Institutional Review Board of Korea University Guro Hospital (2017GR0769 (8 March 2017), 2020GR0451 (7 October 2020)).

Viral RNA extracted from the nasopharyngeal specimens (200 μL each) was performed using the NX-48 viral NA kit (Genolution, Seoul, Republic of Korea) and the Nextractor NX-48 system (Genolution). Nucleic acids were extracted according to the manufacturer’s instructions. SARS-CoV-2 was amplified using real-time RT-PCR, with a commercial Real-Q 2019-nCoV Detection Kit (BioSewoom, Seoul, Republic of Korea). The E and RdRp genes of SARS-CoV-2 were amplified over 40 cycles using the Applied Biosystems 7500 RT-PCR system (Thermo Fisher Scientific, Waltham, MA). Samples were considered as SARS-CoV-2-positive when both targets of viral RNA had been amplified under a cycle threshold (Ct) of 38.0.

Nasopharyngeal and oropharyngeal swabs were collected into T-SWAB TRANSPORT UTMs (Noble Biosciences, Korea) and sputum specimens into 50-mL Falcon tubes containing phosphate buffer (Corning Inc., USA). A QIAamp DSP Viral RNA Minikit (Qiagen GmbH, Germany), QIAcube System (Qiagen GmbH), NX-48 Viral NA Kit (Genolution, Korea), and Nextractor NX-48 System (Genolution) were used for RNA extraction according to the manufacturers’ instructions. SARS-CoV-2 nucleic acid was amplified by rRT-PCR using PowerCheck 2019-nCoV Real-time PCR Kits (Kogenebiotech, Korea). The ABI 7500 real-time PCR system (Applied Biosystems, USA) was used to amplify the E and RdRp genes of SARS-CoV-2 (40 cycles). SARS-CoV-2 infection was diagnosed when both genes were detected under 35.0 cycles.