Sodium dodecyl sulfate capillary gel electrophoresis (reduced and non- reduced) is often used as a purity release assay for monitoring clips in monoclonal antibodies (mAbs). Our criteria for the development of acid hydrolysis of Trastuzumab for injection (Cipla 302) included quantification of clips by both reduced and non- reduced capillary gel electrophoresis thereby comparing its similarity with that of the innovator drug product (Herceptin®). Some of the sample preparation parameters including concentration of HCl, incubation temperature and comparison of Cipla 302 with Herceptin® were investigated. It was observed that a slightly acidic condition and increase in incubation temperature greatly increased the degradation of reduced and non-reduced mAbs. Using this method, it was found that Cipla 302 was almost in the pure form when subjected to harsh conditions like incubation at 50° C and in 0.01 N HCl. The optimal sample preparation conditions to carry out the acid hydrolysis were found to be as follows: (1) concentration of HCl: 0.01N (2) incubation temperature: 70° C. This method was found to be linear in terms of increasing concentration and increasing temperature.