A New Spectrophotometric Method for Determination of Selenium in Cosmetic and Pharmaceutical Preparations after Preconcentration with Cloud Point Extraction

Table 7

The results of limit of detection and relative standard deviation for several reported methods and proposed method.

Method	Limit of detection (ng mL^−1)	Relative standard deviation (%)	Reference
INAA	17	5.0	[6]
Spectrophotometric	12	2.5	[28]
HG-AAS	10.6	1.93	[13]
ET-AAS	5	3.0	[11]
Proposed method	4.4	2.18	—