The solutions were prepared at six concentration levels from limit of quantitations (LOQ) to 250% (LOQ, 0.75, 1.2, 1.5, 2.25, and 3.75 μg mL−1) with respect to the specification level of impurities.
The method was validated using control plants and soil as blank samples spiked with 0.01 μg g−1 and 10 × LOQ 0.1 μg g−1.
Limits of detection ranged from 0.3 to 1.2 μg g−1 and LOQ from 0.9 to 4.0 μg g−1 for the different drugs.
As shown in ESM Table S 1, LOQs for all considered PAHs were in the range 0.1 0.9 μg/kg for the AC and FR materials.
The methodology showed excellent analytical performance with good selectivity, linearity (R2 = 99.9%, r > 0.99), accuracy and low limits (LO D= 0.10 mg L−1 and LOQ = 0.34 mg L−1).
The UA-DSPME-UV vis method performances like excellent linearity (LR), limits of detection (LOD), limits of qUA-DSPME-UV visf 10–5000 μg L−1 with R2 of 0.99, LOD (1.96 ng mL−1), LOQ (6.53 μg L−1), respectively show sUA-DSPME-UV visccurate applicability of the present method for monitoring analytes with within- and between-day performances 0.96–3.38%.
Table 1 Mass spectrometer parameters for nicotine and cotinine detection Analyte MRM transitions* Cone voltage (V) Collision potential (V) LOD (ng · mL-1) LOQ (ng · mL-1) Nicotine 163 > 130 (117) 32 22 1 2.5 Cotinine 177 > 98 (80) 42 30 1 2.5 * m/z of precursor ion > m/z of the fragment used for quantification (m/z of the fragment used for confirmation).
LOQ and LOD were calculated according to the following equation: [23] LOQ = 10 σ / S LOQ = 3.3 σ / S.
LOQ and LOD were calculated according to ICH Q2B recommendations [10]: LOQ = 10 σ/S.
LOQ and LOD were calculated according to the following equations [44]: LOQ = 10 S a / b LOD = 3. 3 S a / b.
The results of LOD and LOQ of MEB and SUL respectively are abridged in Table 2. LOQ and LOD were calculated according to the following equations [10] LOQ = 10 σ/S.
