Purpose: To formulate a dry enteric coating system (solvent free) in development of Lansoprazole delayed release pellets / capsules using Hypromellose Acetate Succinate (HPMCAS).
This work includes formulation development of Lansoprazole delayed release capsules with dry enteric coating approach and thus it’s comparison with that of the solvent coating approach with respect to the process parameters and product performance.
Background of study: As for development of Lansoprazole DR capsules, conventional technique involves drug layering process followed by barrier coat and enteric coat by aqueous or non aqueous coating approach. But the limitation of formulation is that process is time-consuming and also requires huge amount of solvents in the coating process. Hence now a day’s pharmaceutical companies modified the approach to drug layering by powder coating technique on sugar spheres followed by solvent enteric coating which drastically reduced the drug layering process time but still it involves solvent consumption. The extension to this modification, we are targeting on solvent free enteric coating approach using polymer Hypromellose Acetate Succinate AS-LF (HPMCAS) which is a powder coating technique. The trial was conducted on Granurex®, which is having a centrifugal-bowl design for powder-coating.
Methods: Manufacturing method includes dry enteric coating as solvent-free approach. This was conducted on Conical Rotor processor Granurex® (Freund corp.), which is having a centrifugal-bowl design for powder-coating. The enteric polymer used was Hypromellose Acetate Succinate AS-LF (HPMCAS).
So, in this study Lansoprazole was layered on sugar spheres followed by barrier coating in fluidised bed processor by conventional solvent coating approach. Then enteric coating of Lansoprazole pellets by both solvent coating process and dry coating approach with same polymer Hypromellose Acetate Succinate (HPMCAS) was performed. The purpose was to develop Lansoprazole delayed release capsules as per USP specifications.
Evaluation of finished product: So to check the acid resistance and enteric properties of coated pellets following tests were conducted:
1. Assay determination : To check the drug content at initial and even after coating process
2. Dissolution test as per USP : To check the drug release as per criterion mentioned in USP for Lansoprazole delayed release capsules
3. Scanning Electron microscopy (SEM) : To check film formed after dry coating and its uniformity
4. Stability testing : This is to check the stability of product and also stability of film formed after dry coating approach at accelerated conditions.
Results: The enteric coated pellets were analysed for enteric coating properties as per Pharmacopoeial specifications. Assay and dissolution test was performed as per USP monograph of Lansoprazole delayed release capsules in 0.1 N hydrochloric acid (pH 1.2) for first hour followed by phosphate buffer pH 6.8 for next one hour. Results of assay and dissolution study (FIG. 01) are passing the criterion for Lansoprazole DR capsules as per USP, for both the cured as well as uncured pellets. And the results are comparable with that of solvent coating approach.
Conclusion: 1. The development strategy for enteric coating of Lansoprazole pellets by dry coating approach using Hypromellose Acetate Succinate AS-LF (HPMCAS) was reliable, simple and cost effective.
2. Results of dissolution study are claiming that, it is passing the criterion for Lansoprazole DR capsules as per USP, for both the cured as well as uncured pellets by dry coating approach. And these are comparable with that of solvent coating approach.
3. So as an alternative to solvent coating method, dry enteric coating with polymer Hypromellose Acetate Succinate AS-LF (HPMCAS) is most recommended and suitable to minimize time duration and solvent consumption for Lansoprazole DR capsules.
NITIN BHUSANE– Director, Shin-Etsu Chemical Tylose India Pvt. Ltd., Thane, Maharashtra