Removal of Matrix Interferences by Nano-MgO and Co-Adsorbents for Accurate Multi-Pesticide Residue Analysis in the Chinese Medicinal Herb, Paeoniae Radix Alba

Table 1

Recoveries of the spiked pesticides from the various PRA samples at pesticide concentrations of 20, 50, and 200 μg/kg and the number of pesticides not detected (ND) at each concentration.

Recoveries ± RSD (%) for pesticides and the number of nondetects at 20, 50, and 200 μg/kg in each PRA							No. of pesticides with 70−120% recovery at 20, 50, and 200 μg/kg in each PRA
Samples	20 μg/kg	ND^a	50 μg/kg	ND	200 μg/kg	ND	20 μg/kg	50 μg/kg	200 μg/kg
PRA-ZJ	103 ± 5.70	6	106 ± 4.06	0	101 ± 2.72	0	110	110	122
PRA-BZ	103 ± 5.04	8	111 ± 3.84	4	99.5 ± 2.73	0	108	107	121
PRA-SD	100 ± 4.87	13	107 ± 3.33	5	100 ± 2.93	0	109	104	120
PRA-HN	104 ± 4.15	6	108 ± 4.12	0	106 ± 3.09	0	106	107	121
PRA-HB	107 ± 4.43	17	98.0 ± 3.76	4	107 ± 2.88	0	97	117	116
Mean ± RSD	103 ± 4.83		106 ± 3.82		103 ± 2.87
Minimum	100 ± 4.87		98.0 ± 3.76		99.5 ± 2.73
Maximum	107 ± 4.43		111 ± 3.84		107 ± 2.88