Simultaneous Determination of Pesticides in Fruits by Using Second-Order Fluorescence Data Resolved by Unfolded Partial Least-Squares Coupled to Residual Bilinearization

Table 3

Calibration in presence of matrix: test sample analysis applying U-PLS/RBL and evaluation of method determination stage.

Carbaryl μg·L^−1†			Carbendazim μg·L^−1†			Thiabendazole μg.L^−1†
Added	Found banana^†	Found orange^†	Added	Found banana^†	Found orange^†	Added	Found banana^†	Found orange^†
50	43.1 (2)	44.1 (2)	0	7–1 (3)	6 (2)	30	30.1 (2)	26.1 (1)
20	26.0 (1)	17.0 (2)	20	23.0 (4)	21 (1)	0	0 (2)	1.1 (1)
30	33.2 (2)	24.2 (1)	30	36.2 (2)	36 (1)	20	22.1 (1)	19.1 (1)
50	50.3 (2)	54.1 (1)	40	38.3 (3)	44 (1)	40	38.2 (2)	36.4 (2)
30	30.4 (3)	33.0 (1)	0	5.0 (4)	2 (1)	30	27.3 (3)	26.3 (1)
0	3.1 (2)	1.1 (1)	0	4.1 (4)	2 (4)	0	1.1 (1)	2.1 (2)
20	18.2 (1)	22,2 (1)	30	39.0 (5)	29 (3)	20	22.2 (9)	21.1 (3)
15	15.1 (1)	16.1 (1)	0	7.1 (2)	7 (4)	20	19.0 (1)	22.2 (2)
70	71.0 (1)	72.0 (2)	40	40.1 (3)	43 (3)	0	0 (1)	1.1 (2)
70	67.7 (1)	68.2 (2)	70	62.2 (4)	70 (3)	20	25.1 (2)	17,4 (3)
60	59.1 (2)	58.3 (3)	60	52.1 (4)	63 (4)	30	30.2 (2)	27.0 (2)
60	53.0 (2)	56.1 (2)	50	57.0 (3)	54 (4)	30	31.3 (2)	32.1 (2)
40	40.1 (2)	42.1 (4)	0	6.0 (5)	6 (2)	30	25.1 (11)	28.2 (3)
RMSEP μg·L^−1	3.6	3.3		6.1	4.1		2.3	2.6
REP %	3.0	2.8		5.2	3.5		1.9	2.2
LOD μg·L^−1	2.5	2.8		4.0	4.5		1.4	1.8
	5.0	5.4		7.0	7.6		3.9	4.0
LOD mg·kg^−1	0.050	0.056		0.080	0.090		0.028	0.036
	0.100	0.108		0.140	0.152		0.078	0.080
SEN AFU (μg·L^−1)^−1	2.1	1.8		1.9	1.7		7.8	7.4
γ L μg^−1	0.7	0.6		0.6	0.5		2.0	1.8
γ^−1μg·L^−1	1.4	1.7		1.6	1.8		0.5	0.6

RMSEP = root mean square error of prediction. REP % = relative error of prediction. ^†Predicted concentrations, averages of triplicate analysis. Standard deviation in parenthesis. Latent variables for U-PLS A = 4 for all the analytes. Unexpected components N_unx for stabilizing U-PLS residuals s_uN_unx = 1 or N_unx = 2 or N_unx = 3 depending on fruits samples. LOD calculated as an interval [58] SEN = Sensitivity expressed as the ratio between the arbitrary units of fluorescence and concentration (corresponding to the net signal of the analyte at unit concentration; γ = analytical sensitivity calculated as the ratio between the sensitivity (SEN) and the instrumental noise level; γ⁻¹= inverse of analytical sensitivity is the minimum concentration difference which can be measured).