Table 3 DS calibration curves obtained by applying polynomial (2nd degree) and linear regressions
Analytical method | Polynomial fitting | Linear fitting | ||
|---|---|---|---|---|
Equation | R2 | Equation | R2 | |
μFTIR r = \(\text{A}_{3350\,\text{cm}^{-1}}\)/\(\text{A}_{1050\,\text{cm}^{-1}}\) | r = 0.088DS2 − 0.600DS + 1.004 | 0.998 | r = − 0.341DS + 0.896 | 0.948 |
ATR-FTIR r = \(\text{A}_{3330\,\text{cm}^{-1}}\)/\(\text{A}_{1030\,\text{cm}^{-1}}\) | r = 0.039DS2 − 0.262DS + 0.427 | 0.993 | r = − 0.146DS + 0.379 | 0.940 |