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Classification of Annular Bed Flow Patterns and Investigation on Their Influence on the Bottom Spray Fluid Bed Coating Process

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Abstract

Purpose

This study aims to classify annular bed flow patterns in the bottom spray fluid bed coating process, study their influence on coat uniformity and investigate the feasibility of developing real-time annular bed flow pattern detection as a PAT tool.

Methods

High-speed imaging and particle image velocimetry were used to visualize annular bed flow. Color coating and subsequent tristimulus colorimetry were employed to determine influence of annular bed flow pattern on coat uniformity. Feasibility of monitoring annular bed flow pattern through an observation window was tested using miniaturized particle velocity field and time series particle velocity orientation information.

Results

Three types of annular bed flow patterns were identified. Plug flow gave the best coat uniformity followed by global and localized fluidization. Plug flow may be advantageous for high spray-rate conditions, large-scale coating and prevention of particle segregation. Plug flow could be differentiated from the other flow patterns through a simulated observation window.

Conclusion

Annular bed flow patterns were classified and found to influence particle coat uniformity noticeably. Availability of annular bed flow information for large-scale coaters would enable adjustments for process optimization. This study highlights the potential of monitoring annular bed flow pattern as a PAT tool.

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REFERENCES

  1. Porter SC. Coating of tablets and multiparticulates. In: Aulton ME, editor. Aulton's pharmaceutics - the design and manufacture of medicines. New York: Churchill Livingstone; 2007. p. 500–14.

    Google Scholar 

  2. Crites T, Turton R. Mathematical model for the prediction of cycle-time distributions for the Wurster column-coating process. Ind Eng Chem Res. 2005;44:5397–402.

    Article  CAS  Google Scholar 

  3. Saadevandi BA, Turton R. The application of computer-based imaging to the measurements of particle velocity and voidage profiles in a fluidized bed. Powder Technol. 1998;98:183–9.

    Article  CAS  Google Scholar 

  4. Tang ESK, Wang L, Liew CV, Chan LW, Heng PWS. Drying efficiency and particle movement in coating–Impact on particle agglomeration and yield. Int J Pharm. 2008;350:172–80.

    Article  CAS  PubMed  Google Scholar 

  5. Heng PWS, Chan LW, Tang ESK. Use of swirling airflow to enhance coating performance of bottom spray fluid bed coaters. Int J Pharm. 2006;327:26–35.

    Article  CAS  PubMed  Google Scholar 

  6. Cheng X, Turton R. The prediction of variability occurring in fluidized bed coating equipment. I. The measurement of particle circulation rates in a bottom-spray fluidized bed coater. Pharm Dev Technol. 2000;5:311–22.

    Article  CAS  PubMed  Google Scholar 

  7. Sudsakorn K, Turton R. Nonuniformity of particle coating on a size distribution of particles in a fluidized bed coater. Powder Technol. 2000;110:37–43.

    Article  CAS  Google Scholar 

  8. Turton R. Challenges in the modeling and prediction of coating of pharmaceutical dosage forms. Powder Technol. 2008;181:186–94.

    Article  CAS  Google Scholar 

  9. KuShaari K, Pandey P, Song Y, Turton R. Monte Carlo simulations to determine coating uniformity in a Wurster fluidized bed coating process. Powder Technol. 2006;166:81–90.

    Article  CAS  Google Scholar 

  10. Yu LX. Pharmaceutical quality by design: product and process development, understanding, and control. Pharm Res. 2008;25:781–92.

    Article  CAS  PubMed  Google Scholar 

  11. Palmer SE, Seville JPK, Ingram A, Fitzpatrick S, Fan X. Tracking particle motion in a Wurster coater using positron emission, Fifth World Congress on Particle Technology (Session #158b) on 2006 AIChE Spring National Meeting. Orlando: American Institute of Chemical Engineers; 2006.

    Google Scholar 

  12. Bi X, Pugsley T. Investigation of the sources of variability in the Wurster coater: analysis of particle cycle times using PEPT. In: Berruti F, editor. 2007 ECI Conference on The 12th International Conference on Fluidization—New Horizons in Fluidization Engineering. Vancouver: The Berkeley Electronic Press; 2007. p. 431–40.

    Google Scholar 

  13. Liew CV, Wang LK, Heng PWS. Development of a visiometric process analyzer for real-time monitoring of bottom spray fluid-bed coating. J Pharm Sci. 2010;99:346–56.

    Article  CAS  PubMed  Google Scholar 

  14. Christensen FN, Bertelsen P. Qualitative description of the Wurster-based fluid-bed coating process. Drug Dev Ind Pharm. 1997;23:451–63.

    Article  CAS  Google Scholar 

  15. Rhodes M. Fluidization. Introduction to particle technology. New York: Wilety; 1998. p. 97–110.

    Google Scholar 

  16. Chan LW, Tang ESK, Heng PWS. Comparative study of the fluid dynamics of bottom spray fluid bed coaters. AAPS PharmSciTech. 2006;7:37–64.

    Article  Google Scholar 

  17. Smits AJ, Lim TT. Flow visualization: techniques and examples. River Edge: Imperial College Press; 2000. p. 2–26.

    Book  Google Scholar 

  18. Adrian RJ. Particle-imaging techniques for experimental fluid mechanics. Annu Rev Fluid Mech. 1991;23:261–304.

    Article  Google Scholar 

  19. Keane RD, Adrian RJ. Theory of cross-correlation analysis of PIV images. Appl Sci Res. 1992;49:25.

    Article  Google Scholar 

  20. Westerweel J. Fundamentals of digital particle image velocimetry. Meas Sci Technol. 1997;8:1379–92.

    Article  CAS  Google Scholar 

  21. Westerweel J. Digital particle image velocimetry: theory and application, Ph.D thesis, Technische Universiteit Delft, Delft, Netherlands; 1993. p. 236

  22. Conway S, Lekhal A, Khinast J, Glasser B. Granular flow and segregation in a four-bladed mixer. Chem Eng Sci. 2005;60:7091–107.

    Article  CAS  Google Scholar 

  23. Darelius A, Lennartsson E, Rasmuson A, Niklasson Bjorn I, Folestad S. Measurement of the velocity field and frictional properties of wet masses in a high shear mixer. Chem Eng Sci. 2007;62:2366–74.

    Article  CAS  Google Scholar 

  24. Duursma GR, Glass DH, Rix SJL, Yorquez-Ramirez MI. PIV investigations of flow structures in the fluidised bed freeboard region. Powder Technol. 2001;120:2–11.

    Article  CAS  Google Scholar 

  25. Nilpawar A, Reynolds G, Salman A, Hounslow M. Surface velocity measurement in a high shear mixer. Chem Eng Sci. 2006;61:4172–8.

    Article  CAS  Google Scholar 

  26. Ostendorf M, Schwedes J. Application of particle image velocimetry for velocity measurements during silo discharge. Powder Technol. 2005;158:69–75.

    Article  CAS  Google Scholar 

  27. Slominski C, Niedostatkiewicz M, Tejchman J. Application of particle image velocimetry (PIV) for deformation measurement during granular silo flow. Powder Technol. 2007;173:1–18.

    Article  CAS  Google Scholar 

  28. Suh YK. Multi-frame MQD-PIV. KSME Int J. 2003;17:1552–62.

    Google Scholar 

  29. Mori N, Chang K-A. Introduction to MPIV—user reference manual. http://www.oceanwave.jp/softwares/mpiv (accessed September 2009).

  30. Nakayama Y, Boucher RF. Introduction to fluid mechanics. New York: Wiley; 1999. p. 42.

    Google Scholar 

  31. Cole G, Aulton ME, Hogan JE. Pharmaceutical coating technology. Bristol: Taylor & Francis; 1995. p. 1–5.

    Google Scholar 

  32. Wirth M. Instrumental color measurement— method for judging the appearance of tablets. J Pharm Sci. 1991;80:1177–9.

    Article  CAS  PubMed  Google Scholar 

  33. Chan LW, Chan WY, Heng PWS. An improved method for the measurement of colour uniformity in particle coating. Int J Pharm. 2001;213:63–74.

    Article  CAS  PubMed  Google Scholar 

  34. Lehmann K. Coating of multiparticulates using polymeric solutions—formulation and process considerations. In: Ghebre-Sellassie I, editor. Multiparticulate oral drug delivery. New York: Marcel Dekker; 1994. p. 51–76.

    Google Scholar 

  35. Fukumori Y. Coating of multiparticulates using polymeric dispersions—formulation and process considerations. In: Ghebre-Sellassie I, editor. Multiparticulate oral drug delivery. New York: Marcek Dekker; 1994. p. 79–111.

    Google Scholar 

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ACKNOWLEGMENTS

The authors acknowledge the funding support from the National University of Singapore Academic Research Fund (R-148-000-085-112).

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Authors and Affiliations

  1. GEA-NUS Pharmaceutical Processing Research Laboratory, Department of Pharmacy, National University of Singapore, 18 Science Drive 4, Singapore, 117543, Singapore

    Li Kun Wang, Paul Wan Sia Heng & Celine Valeria Liew

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  1. Li Kun Wang
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  2. Paul Wan Sia Heng
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  3. Celine Valeria Liew
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Correspondence to Celine Valeria Liew.

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Wang, L.K., Heng, P.W.S. & Liew, C.V. Classification of Annular Bed Flow Patterns and Investigation on Their Influence on the Bottom Spray Fluid Bed Coating Process. Pharm Res 27, 756–766 (2010). https://doi.org/10.1007/s11095-009-0046-5

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  • DOI: https://doi.org/10.1007/s11095-009-0046-5

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