A validated spectrofluorimetric method for the determination of nifuroxazide through coumarin formation using experimental design

Table 4 Assay parameters and method validation obtained by applying spectrofluorimetric method for the determination of NF

Parameter	NF
Excitation wavelength	340 nm
Emission wavelength	390 nm
Range of linearity	20 - 400 ng ml^-1
Regression equation	y = 1448.447x + 101.590
Correlation coefficient (r)	0.9997
S _b	14.185
S _a	3.477
Confidence limit of the slope	1448.447 ± 45.137
Confidence limit of the intercept	101.590 ± 11.064
Standard error of the estimation	4.310
LOD^a	0.01 ng ml^-1
LOQ^a	0.03 ng ml^-1
Intraday^b
% RSD	0.692 – 0.598
Interday^c
% RSD	0.688 – 0.395

^a Limits of detection and quantification are determined via calculations [29]:
LOD= 3.3×SD/slope LOQ= 10×SD/slope, where SD is standard deviation of response.
^b The intraday (n = 3), average of two concentrations of NF (100, 350 ng ml⁻¹), repeated three times within the day.
^c The interday (n = 3), average of two concentrations of NF (100, 350 ng ml⁻¹), repeated three times in three successive days.

ISSN: 2661-801X