Table 2. Specific solvents and wavelengths for each active ingredient

API	Solvents	Wavelengths (nm)
Ibuprofen	NaOH 0.1 N	221
Aspirin	NaOH 0.1 N	297
Paracetamol	NaOH 0.1 N	257
Metronidazole	Water	321
Diltiazem hydrocloride	Water	236
Sodium diclofenac	Water	276
Cefuroxime axetil	HCl 0.1 N	281

API, active pharmaceutical ingredients.