Fig. 2. Optimisation of LAMP and its compatibility to undergo lyophilisation. (A) Effect of the concentration of MgSO4 using Bst 2.0 WarmStart (Bst 2.0 WS) and Bst 2.0. DNA polymerase (Bst 2.0). An additional concentration is included in the reaction (the isothermal solution already contains 2 mM). (B) Effect of the concentration of dNTPs using Bst 2.0 WS and Bst 2.0. (C) Effect of incorporating Betaine (50% glycerol) and a glycerol-free version. (D) Effect of incorporating BSA (50% glycerol) and a glycerol-free version. (E) Impact of the addition of glycerol at various final concentrations (% in the reaction) in a glycerol-free LAMP raction mix. (F) Comparison of the NEB protocol and the proposed glycerol-free protocol using Bst 2.0 WS and its glycerol-free version. (G) Analytical sensitivity of the lyo-LAMP beads in comparison to the liquid format using a serial 10-fold dilution of SARS-CoV-2 RNA. (H) ΔpH values of lyo-LAMP and liquid LAMP before and after amplification across various concentrations of SARS-CoV-2 RNA.
