Determination of oxybuprocaine HCL in pharmaceutical formulations using thermal techniques

A.Merey, H., F. A.Morsy, M. A.Mohammed, and M. Y.Salem, "Determination of oxybuprocaine HCL in pharmaceutical formulations using thermal techniques", Analytical Chemistry An Indian Journal , vol. 15, issue 9, pp. 379-386, 2015.


The thermal behavior of oxybuprocaine hydrochloride (OXY) has been studied.
Thermogravimetric analysis (TGA), derivative thermogravimetry (DTG)
and differential thermal analysis (DTA) techniques were used to study the
thermal behavior of the drug.
Thermal-analytical study showed that OXY is thermally decomposed in
four steps. The first step occurs in the temperature range of 62.05- 166.70 ºC,
the second step occurs at 166.70 -354.91 ºC, the third step occurs at 354.91
- 455.52 ºC and the fourth step at 455.52–489.05 ºC. Melting point of OXP
was recorded at 160.15 ºC.
Thermodynamic parameters such as activation energy (Ea), frequency factor
(A), reaction order (n), and correlation coefficient (r) were calculated
using different kinetic models. The purity value for the drug was found to
be 99.36%. Thermal analysis technique gave satisfactory results to obtain
quality control parameters such as melting point, water content and ash
content in comparison to those obtained using official methods. Thermal
analysis justifies its application in quality control of pharmaceutical compounds
due to its simplicity, sensitivity and low operational costs. DSC
results indicated that the degree of purity of Oxybuprocaine HCl is similar
to that found by official method.