Issue link: https://www.e-digitaleditions.com/i/446555
Figure 12 Terahertz sampling patterns for in-line analysis a. Small spot monitors single track b. Small spot traverses ribbon c. Cylindrical lens generates large elliptical spot Figure 11 Effect of process parameters on ribbon apparent density cross section: Variable gap with fixed roller speed (1 rpm) and 2D RI maps 10 20 30 40 a. 0.8 mm Width, Y (mm) Width, Y (mm) 20 10 0 -10 -20 Length, X (mm) 10 20 30 40 c. Average apparent density cross-section projection line plot (0.8 mm) d. Average apparent density cross-section projection line plot (1 mm) 10 20 30 40 b. 1 mm 20 10 0 -10 -20 Length, X (mm) 2 1.5 1 0.5 0 Apparent density (g/cm 3 ) -30 -20 -10 0 10 20 30 2 1.5 1 0.5 0 Width, Y (mm) Apparent density (g/cm 3 ) -30 -20 -10 0 10 20 30 2 1.5 1 0.5 0 Width, Y (mm) Terahertz Section Terahertz Section Tablets & Capsules January 2015 33 Conclusions Terahertz spectroscopy is a fast, non-destructive, non- contact technique for measuring density (solid fraction, percentage porosity), which is the most important CQA of roller-compacted ribbons. This information can be used to optimize process parameters during development, facilitate scale-up, and to control the process during continuous manufacturing. T&C References 1. Sullivan, M.J., King, E.; Kato, E.; Heaps, D.; McKay, R.; Zhou, X.H. Using terahertz spectroscopy to map tablet cores and coatings. Tablets & Capsules, 2013. 11(7): pp. 10-16. 2. Miguélez-Morán, A.M., Wu, C.Y., Dong, H., and Seville, J.P.K. Characterisation of density distributions in roller-compacted ribbons using micro-indentation and X- ray micro-computed tomography. Eur J Pharm Biopharm, 2009. 72(1): pp. 173-182. 3. Lim, H., Dave, V.S., Kidder, L., Neil Lewis, E., Fahmy, R., and Hoag, S.W. Assessment of the critical factors affecting the porosity of roller compacted ribbons and the feasibility of using NIR chemical imaging to evaluate the porosity distribution. Int J Pharm, 2011. 410(1-2): pp. 1-8. 4. Samanta, A.K., Karande, A.D., Ng, K.Y., and Heng, P.W.S. Application of near-infrared spectroscopy in real- time monitoring of product attributes of ribbed roller compacted flakes. AAPS PharmSciTech, 2013. 14(1): pp. 86-100. 5. Akseli, I., Iyer, S., Lee, H.P., and Cuitiño, A.M. A quantitative correlation of the effect of density distributions in roller-compacted ribbons on the mechanical properties of tablets using ultrasonics and X- ray tomography. AAPS PharmSciTech, 2011. 12(3): pp. 834-853. 6. May, R.K., Su, K., Han, L., Zhong, S., Elliott, J.A., Gladden, L.F., Evans, M., Shen, Y., and Zeitler, J.A. Hardness and density distributions of pharmaceutical tablets measured by terahertz pulsed imaging. J Pharm Sci, 2013 102(7): pp. 2179-86. 7. Palermo, R., Cogdill, R.P., Short, S.M., Drennen III, J.K., and Taday, P.F. Density mapping and chemical component calibration development of four-component compacts via terahertz pulsed imaging. J Pharmaceut Biomed, 2008. 46(1): pp. 36-44. 8. Hancock, B.C., Colvin, J.T., Mullarney, M.P., and Zinchuk, A.V. The Relative Densities of Pharmaceutical Powders, Blends, Dry Granulations, and Immediate- Release Tablets. Pharm Tech, 2003(April): pp. 64-80. Mark Sullivan is a senior R&D scientist; David Heaps and Richard McKay are principal scientists; Eiji Kato is a terahertz technology expert; and Xiao Hua Zhou is an analytical scientist at Advantest America, 508 Carnegie Center, Suite 102, P r i n c e t o n , N J 0 8 5 4 0 . Te l . 6 0 9 8 9 7 7 3 2 0 . E - m a i l : mark.sullivan@advantest.com. Chuan-Yu Wu is a professor in the Department of Chemical and Process Engineering at the University of Surrey, Guildford, GU2 7XH UK. Chun-lei Pei, Jian-yi Zhang, and Serena Schiano are members of Wu's research group.