Quantification of Sunscreen Benzophenone-4 in Hair Shampoos by Hydrophilic Interactions Thin-Layer Chromatography/Densitometry or Derivative UV Spectrophotometry

Table 1

Parameters of calibration plots.

	Chromatography/densitometry	Spectrophotometric 0 derivative; 285 nm	Spectrophotometric 2nd derivative; 285 nm
Calibration plot
	0.9990	0.9999	0.9999
IDL	0.03 μg spot^−1	0.001 mg mL^−1	0.001 mg mL^−1
IQL	0.1 μg spot^−1	0.003 mg mL^−1	0.003 mg mL^−1