TABLE 1.

Summary of literature review of different loop-mediated isothermal amplification (LAMP) processing methods

Processing method	Source,a y	Approximate sensitivity or LoD	Sample type
65°C for 30 min	L'Helgouach et al. 2020	73% Sensitivity at qPCR Ct < 35.	Saliva
95°C for 15 min	Alekseenko et al. 2021	Sensitivity comparable to qPCR at Ct = 20–25	NP swabs
95°C for 5 min	Thi et al. 2020	Sensitivity comparable to qPCR at Ct = 25–30	NP swabs
Chelex-100, DTT	Howson et al 2020	Sensitivity comparable to qPCR at Ct = 25–30	Saliva
Chelex-100	Flynn et al. 2020	100 copies/μL	Saliva
Proteinase K	Ben-Assa et al. 2020	Sensitivity comparable to qPCR at Ct = 28	NP swabs in UTM, saliva
Proteinase K	Azmi et al. 2020*	10 copies/reaction	Saliva
Proteinase K (QuickExtract)	Joung et al. 2020*	100 copies/reaction	NP swab in VTM
Proteinase K (QuickExtract)	Nguyen et al. 2020*	1 copy/μL	NP swabs
Semialkaline proteinase	Yamazaki et al. 2021	170–230 copies/μL	Saliva
TCEP/EDTA (Quick Extract)	Agrawal et al. 2021*	40 copies/μL	Saliva
TCEP/EDTA or DTT/EDTA	Rabe and Cepko 2020	50 copies/μL	Saliva, NP swabs
TCEP/EDTA	Sherrill-Mix et al. 2021a and 2021b	100 copies/μL	Saliva
TCEP, proteinase K	Yang et al. 2021	200 copies/μL	Saliva
TCEP, RNASecure, proteinase K	Lalli et al. 2021	25 copies/μL	Saliva
Thermolabile proteinase K	Wei et al. 2020	2.5 copies/μL	NP swabs in VTM

Abbreviations: C_t, cycle threshold; DTT, dithiothreitol; LAMP, loop-mediated isothermal amplification; LoD, limit of detection; qPCR, quantitative polymerase chain reaction; TCEP, tris(2-carboxyethyl)phosphine; UTM, universal transport medium; VTM, viral transport medium.

^aAsterisks (*) indicate sensitivity reported using a combination reverse transcription–LAMP/recombinase polymerase amplification (RT-LAMP/RPA) with CRISPR-Cas detection; otherwise, only RT-LAMP was used.