H-Point Standard Additions method for the simultaneous determination of Paracetamol and Chlorzoxazone in Tablets using addition of both analytes and absorbance increment (?A)

Mohammed Abdeen Mohammed, Imad Osman Abu Reid, Alaa Elawni


The suitability of H-point standard additions method (HPSAM) to resolve of overlapping spectra corresponding to the paracetamol and chlorzoxazone was verified. The results showed that the H-point standard additions method with simultaneous addition of both analytes utilizing absorbance increment is suitable for the simultaneous determination of paracetamol and chlorzoxazone.

The results of applying the H-point standard additions method showed that the two drugs could be determined simultaneously with the concentration ratios of paracetamol to chlorzoxazone varying from 1:2 to 2:1 in the mixed samples. In addition the means of the calculated RSD (%) were 1.40 and 1.92 in synthetic mixtures with 1.29 and 1.68 in dosage form for paracetamol and chlorzoxazone, respectively.


Spectrophotometric, Paracetamol, Chlorzoxazone, H-point standard additions method, absorbance increment, absorbance increment

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DOI: https://doi.org/10.7439/ijapa.v7i1.4006


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