Spectrophotometric Determination of Chlorzoxazone in pure State and Formulations Through Oxidative Coupling of its Hydrolysis Product

ABSTRACT

Three simple and sensitive procedures (Methods A, B and C) for the assay of chlorzoxazone (CZZ) in pure form and in formulations are described. The methods are based on the oxidative coupling reaction of the hydrolysis product of chlorzoxazone (HCZZ) with 3-methyl-2-benzothiazolinone hydrazone (MBTH) in the presence of Fe (III) (Method A, λ_max 445 nm), N, N-dimethyl-p-phenylene diamine (DMPD) in the presence of periodate (IO₄) (method B, λ_max 605 nm) and 2, 6-dichloroquinone chlorimide (DCQC) (Method C, λ, _max 560 nm). The Beer's law limits were found to be 5.0 to 25.0 μg/ml in the case of methods A and B and 2.0 to 12.0 μg/ml in the case of method C. The results are statistically validated and the reactions involved are presented.

Keywords::

• Chlorzoxazone
• Muscle relaxants
• 3-Methyl-2-benzothiazoli-none hydrazone
• N, N-dimethyl-p-phenylene diamine
• 2, 6-dichloroquinone chlorimide
• Visible spectrophotometry