A reverse phased high performance liquid (HPLC) method was developed for the determination of (TLP) drug substance and it impurities TLPRC01, TLPRC02, TLPRC03, TLPRC04, TLPRC05 and TLPC06 using an analytical column Unison UK-C18, (250mm x4.6mm, 5µ) maintained at 30oC±2oC. The wavelength was set at 265 nm. Flow rate was maintained as 1.0 ml/min with injection volume of 10 . All the could be separated with run time of 60 min. The peaks of are well resolved with the resolution of 2.0. The results of all the validation parameters showed that the developed method is well confined to the limits of ICH guidelines. Degradation studies showed that the mass balance of in all conditions is in the range of 98 to 102 %. The accuracy of six impurities TLPRC01, TLPRC02, TLPRC03, TLPRC04, TLPRC05 and TLPC06 found in the range of 80-120%. The proposed method is able to quantify the related compounds present in drug substance and also able to see the assay of drug substance in presence of degraded impurities without the loss of purity of drug substance and other impurities. The method has proved to be robust by introducing changes in the conditions.

Blonanserin an antipsychotic novel drug used for the treatment of schizophrenia has antagonist properties for dopamine D2 and serotonin 5-HT2. On the other hand, it lacks adrenergic-α1, muscarinic M1, and histamine H1 antagonist activities. Clinical studies demonstrated in Japan had shown to be more effective for treating negative as well as positive schizophrenic symptoms. This drug was accepted and approved worldwide in the treatment of schizophrenia. A new HPLC method was developed and validated for the estimation of Impurities of Blonanserin (BNS) to ensure that the methodology meets the requirements of the target analysis application. Active and efficient chromatographic separation was achieved on a  Zorbax Bonus RP EP C18 column having a particle size of 5μm, with dimensions of 250mm × 4.6 mm, mobile phase containing pH 2.4 buffer and Organic, with 1.0 ml /min flow rate,  column oven temperature at 30oC and the eluent detection at 245 nm. The method shows well-separated impurities, is specific without interference from blank solution with resolution more than 1.2 between any of the impurity, correlation coefficient more than 0.99 showing good linearity; mean recovery ranging from 97% to 105% and is very sensitive at lower detection and quantification limits. This method was well developed and has been applied successfully to monitor and estimate impurities in Blonanserin.