Degradation Study of Methylcobalamin Injection and Change in pH by Thermal Stress

Trigeminal neuralgia, diabetic neuropathy, facial paralysis and megaloblastic anemia can be treated by the use of Methylcobalamin injection. An accurate, simple, economical, precise and reproducible UV Spectrophotometric method has been developed for the assessment of Methylcobalamin in injection dosage form and validated by ICH guidelines. The standard solution (10μg/ml) was scanned between 200-400 nm and maximum absorption was recorded at 353 nm. The assay results originated98.94%. The percent recovery was calculated as 99.05% to 100.50 %. The linearity range of 10-50 μg/ml proved that it obeyed Beer's Law. 2 ) was found to be 0.99 at 353 nm with an intercept of 0.0105 and a slope of 0.0121 with RSD 1.33 complied ICH. In forced degradation study (thermal stress) we observed that Methylcobalamin assay become decreased due to thermal stress and there is slightly change in pH. The proposed method was accurate, precise, and reproducible. The commonly used excipients in formulation were not interfering. The drug was found to be unstable in heat conditions.