Skip to main content
. 2021 Oct 31;26(21):6617. doi: 10.3390/molecules26216617

Figure 2.

Figure 2

Analytical performance of saliva-based one-step RT-LAMP and RT-qPCR. (A) Effect of Syto9 fluorescent dye on RT-LAMP amplification using the N2 primer set and WarmStart Master Mix. The RNA diluted in water (315 copies per reaction) was amplified in 20 µL reaction volume (n = 11). The melting curves of the amplified target in the presence of Syto9 fluorescent dye are depicted. (B,C) LoD of RT-LAMP. (B) RNA (Twist) was amplified with N2 primer set in 20 µL reaction volume using the WarmStar Master Mix. (C) RNA (INSTAND) was amplified with N2 or E1 primer in 15 µL reaction volume using an Isothermal Master Mix. Serial dilutions of standard viral RNA were prepared in heat-treated SARS-CoV-2-negative saliva (n = 7 (B); n = 6 (C)). (D–F) LoD of RT-qPCR. (D,E) RNA (Twist) was amplified using Ultraplex Master Mix in 20 µL reaction volume as a singleplex with N1 primer–probe set (n = 20) (D) or as a multiplex with N1 and N2 primer–probe set (n = 16) (E). (F) RNA (INSTAND) was amplified using AgPath-ID Master Mix in 15 µL reaction volume as a singleplex with N1 and N2 primer–probe set (n = 16). (D–F) Serial dilutions of standard SARS-CoV-2 viral RNA were prepared in heat-treated SARS-CoV-2-negative saliva. A vertical dashed line indicates a lower LoD. A horizontal dotted line indicates the Cq cut-off value.