Survey of ERETIC2 NMR for quantification

Abstract The ERETIC (Electronic REference To access In vivo Concentrations)2 method is a new qNMR experimental technique to measure analytes based on the signal of the reference compound without additional hardware equipment. In this study, ERETIC 2 method was validated, and we sought to identify whether it would be possible to apply this method to a specific compound analysis of metabolites in plant. The 90° pulse value (P1) and spin -lattice relaxation time ( T 1 ) of each compound were measured for ERETIC 2. The 9 1 H of 3-(trimethylsilyl) propionic -2,2,3,3 -d 4 acid (TSP) was used as a reference peak for ERETIC 2, and then, a suitable solvent and pulse sequence for each compound were selected. Under the NOESY -presat sequence, the relative accuracy e rror for quantitative analyses of primary metabolites was within the range of 5%, with the exception of glucose, which showed • 5% error due to saturation. It showed excellent results for the quantification of glucose by using a 30° pulse sequence, which did not suppress the water peak. In addition, the qua ntitative accuracy for secondary metabolites was extremely accurate, with DQ HUURU ” ZKHQ FRQVLGHULQJ WKH SXULW\ RI WKHstandard sample. The ERETIC 2 method showed outstanding linearity, precision, and accuracy. Keywords qNMR, ERETIC , quantification Introduction Nuclear magnetic resonance (NMR) is a qualitative and quantitative analytical technique. It is the only physical method used routinely that can provide quantitative valuable information at the molecular level. Therefore NMR has found various a pplications in other fields than chemistry, such as metabolomics methodology