Table 4.
Repeatability relative standard deviation and reproducibility relative standard deviation for ascorbic acid from rugosa rose fruit

Rugosa rose extract		Retention time (min)	Area (µAU)	Ascorbic acid concentration (µg/mL)	Ascorbic acid (%)
Intra-day (Day 1, analyst 1)
50 µg/mL	Average	2.62	51594	0.27	73.46
	SDa	0.00	1523	0.01	1.80
	RSDb	0.02	2.95	3.70	2.45
100 µg/mL	Average	2.625	105604	0.54	77.94
	SD	0.00	308	0.00	1.95
	RSD	0.07	0.29	0.81	2.52
150 µg/mL	Average	2.62	157362	2.68	79.52
	SD	0.00	1442	0.06	2.09
	RSD	0.06	0.97	2.22	2.63
Intra-day (Day 2, analyst 2)
50 µg/mL	Average	2.62	50322	0.28	77.97
	SD	0.01	255	0.00	1.99
	RSD	0.25	0.51	0.54	2.56
100 µg/mL	Average	2.63	106289	0.57	76.05
	SD	0.01	658	0.03	1.29
	RSD	0.20	0.62	4.76	1.70
150 µg/mL	Average	2.63	156271	2.63	76.27
	SD	0.00	2301	0.10	2.75
	RSD	0.17	1.47	3.61	3.61
Inter-day (RSD)
50 µg/mL		0.16	2.35	3.23	3.96
100 µg/mL		0.13	0.56	4.56	2.34
150 µg/mL		0.12	1.16	2.83	3.61

Standard deviation
Relative standard deviation (%)