A novel isocratic HPLC method to separate and quantify acetanilide and its hydroxy aromatic derivatives: 2-, 3- and 4-hydroxyacetanilide (paracetamol or acetaminophen).

Reverse-phase high performance liquid chromatography on a microBondapak C-18 Column has been used to separate and quantify acetanilide and its aromatic monohydroxy derivatives in the 2-, 3- and 4- positions. Separation was achieved within 22 min by using an isocratic mixture of 2-propanol: methanol: water, 8:18:74 (v/v). This method compares very favourably with other HPLC techniques already reported to separate acetanilide from the monohydroxy aromatic derivatives.