Fig. 2From: Amino acids on witness coupons collected from the ISAS/JAXA curation facility for the assessment and quality control of the Hayabusa2 sampling procedurea The procedure of the amino acid analysis of the witness coupons. Each of the steps in the extraction, acid hydrolysis and derivatisation processes was conducted in flame-sealed glass ampoules to minimise any contamination. b Calibration lines for the quantification of amino acids detected on the witness coupons. Nine different concentrations of authentic amino acid standard mixtures ranging from 0.5 to 1 × 10−6 nmol/injection were analysed using GC/NPD to draw these lines. Note that the error accompanying the GC/NPD analysis was within ca. 5%Back to article page