Simultaneous Estimation and Stability Studies of Loperamide Hcl and Norfloxacin in Combined Dosage form by Reverse Phase High-Performance Liquid Chromatography.

A Simple, Precise, Accurate RP-HPLC Method Has Been Developed And Validated For The Analysis And Stability Studies Of Norfloxacin (NOR) And Loperamide (LOP) In Combined Dosage Form. The Chromatographic Separation And Quantization Of NOR And LOP In HPLC Was Achieved On A C-18(250 X 4.6 Mm 5 Μm) Column Using The Mobile Phase In Isocratic Mode Constituting Of Eluent ACN: Water: H3PO4 (Ph Adjusted To 4.5 With Triethylamine) In The Ratio 50:50:0.2 V/V/V At A Flow Rate Of 1 Ml/Min. Eluted Components Were Detected At 222 Nm. The Method Showed High Sensitivity And Good Linearity Over The Concentration Range Of 5 To 25 Μg/Ml, Y=32737 X – 4790, Y=24054 X + 3766 And The Correlation Coefficient R2 Was Found To Be 0.9998, 0.9995 For NOR And LOP Respectively. The Retention Time Was Found To Be 2.09 For NOR And 4.51 For LOP. The Method Validation Was Carried Out As Per ICH Guidelines. The LOD And LOQ Were Found To Be 1.17 Μg/Ml And 3.59 Μg/Ml For NOR And 0.16 Μg/Ml And 0.39 Μg/Ml For LOP Respectively. The Mean Recovery Values For NOR And LOP Was Found To Be In The Range Of 99.46 – 100.76 %. The Method Was Specific And No Interference Was Observed When The Drugs Were Estimated In Presence Of Excipients. The Method Was Validated For Linearity, Range, Precision, Accuracy, Ruggedness And Robustness. After The Validation The Method Was Successfully Applied For The Estimation Of Norfloxacin And Loperamide In Combined Dosage Form