Author(s):
Vijay Patel, Jaswandi Mehetre, Vimal Kumar, Kalpesh Upadhyay, Tushar Mehta, Anirban Roy Chowdhury
Email(s):
vijay293patel@gmail.com
DOI:
10.52711/2231-5675.2025.00020
Address:
Vijay Patel1*, Jaswandi Mehetre1, Vimal Kumar1, Kalpesh Upadhyay1, Tushar Mehta2, Anirban Roy Chowdhury2
1School of Pharmacy, ITM (SLS) Baroda University, Vadodara, Gujarat, India.
2Amneal Pharmaceutical Pvt. Ltd., Pharma-SEZ, Matoda, Ahmedabad, Gujarat.
*Corresponding Author
Published In:
Volume - 15,
Issue - 2,
Year - 2025
ABSTRACT:
The amorphous form of pharmaceutical materials represents a material's most energetic solid state. It provides advantages in terms of dissolution rate and bioavailability. During the formulation process (like Micronisation, compaction, and blending,) predominantly crystalline materials are converted to amorphous fractions. The presence of a small amount of amorphous material is known or unknown to impact drug product performance. In-meter dose inhaler (MDI) and dry powder inhaler (DPI), dosage forms very low micron drug substance required. During Micronisation, the crystallinity of the drug substance in MDIs and DPIs can be affected by mechanical processing, including Micronisation. This can lead to the generation of amorphous thermodynamically unstable particles, which tend to convert to a more stable crystalline state. This recrystallization of micronized material could lead to uncontrolled particle growth, thereby affecting the critical quality attributes of the MDI or DPI product (e.g., aerosol particle size distribution (APSD) and delivered dose uniformity (DDU). Therefore, quantifying the amorphous fraction is essential to ensure the drug product meets its specifications. This paper discusses a complementary amorphous standard preparation technique and analytical technique that can quantify amorphous content accurately and precisely in many active pharmaceuticals. These techniques include Differential Scanning Calorimetry (DSC), FT-Raman, X-ray diffraction technique (XRPD), Modulated DSC (MDSC), Continuous Relative Humidity Perfusion Microcalorimetry, Dynamic Vapor Sorption (DVS), and Solution Calorimetry (SC).
Cite this article:
Vijay Patel, Jaswandi Mehetre, Vimal Kumar, Kalpesh Upadhyay, Tushar Mehta, Anirban Roy Chowdhury. Qualitative and Quantitative Approach for Amorphous Content Determination in Active Pharmaceuticals. Asian Journal of Pharmaceutical Analysis. 2025; 15(2):123-0. doi: 10.52711/2231-5675.2025.00020
Cite(Electronic):
Vijay Patel, Jaswandi Mehetre, Vimal Kumar, Kalpesh Upadhyay, Tushar Mehta, Anirban Roy Chowdhury. Qualitative and Quantitative Approach for Amorphous Content Determination in Active Pharmaceuticals. Asian Journal of Pharmaceutical Analysis. 2025; 15(2):123-0. doi: 10.52711/2231-5675.2025.00020 Available on: https://ajpaonline.com/AbstractView.aspx?PID=2025-15-2-9
REFERENCE:
1. USFDA. 2007. Guidance for industry. ANDAs: Pharmaceutical. Solid polymorphism. Chemistry, Manufacturing, and Controls (http://www.fda.gov/downloads/Drugs/Guidances/UCM072866.pdf).
2. Metered Dose Inhaler (MDI) and Dry Powder Inhaler (DPI) Products - Quality Considerations Guidance for Industry (DRAFT GUIDANCE) April 2018; U.S. Department of Health and Human Services Food and Drug Administration Centre for Drug Evaluation and Research (CDER)
3. Murphy BM, Prescott SW, Larson I. Measurement of lactose crystallinity using Raman spectroscopy. J Pharm Biomed Anal. 2005; 38(1): 186–190, https://doi.org/10.1016/j.jpba.2004.12.013
4. Gombas A, Antal I, Szabo-Revesz P, Marton S, Eros I. Quantitative determination of crystallinity of alpha-lactose monohydrate by near infrared spectroscopy (NIRS). Int J Pharm. 2003; 256(1): 25–32, https://doi.org/10.1016/S0378-5173(03)00059-0
5. Hogan SE, Buckton G. The application of near infrared spectroscopy and dynamic vapor sorption to quantify low amorphous contents of crystalline lactose. Pharm Res. 2001; 18(1): 112–116, https://doi.org/10.1016/j.jpba.2004.12.013
6. Newell HE, Buckton G, Butler DA, Thielmann F, Williams DR. The use of inverse phase gas chromatography to measure the surface energy of crystalline, amorphous, and recently milled lactose. Pharm Res. 2001; 18(5): 662–666, DOI: 10.1023/a:1011089511959
7. Briggner L, Buckton G, Bystrom K, Darcy P. The use of isothermal microcalorimetry in the study of changes in crystallinity induced during the processing of powders. Int J Pharm. 1994; 105(2): 125–135, https://doi.org/10.1016/0040-6031(94)01894-M
8. Dilworth SE, Buckton G, Gaisford S, Ramos R. Approaches to determine the enthalpy of crystallization, and amorphous content, of lactose from isothermal calorimetric data. Int J Pharm. 2004; 284(1): 83–94, https://doi.org/10.1016/j.ijpharm.2004.07.016
9. Hogan SE, Buckton G. The quantification of small degrees of disorder in lactose using solution calorimetry. Int J Pharm. 2000; 207(1): 57–64, https://doi.org/10.1016/S0378-5173(00)00527-5
10. Gustafsson C, Lennholm H, Iversen T, Nystrom C. Comparison of solid-state NMR and isothermal microcalorimetry in the assessment of the amorphous component of lactose. Int J Pharm. 1998; 174(1): 243–252, https://doi.org/10.1016/S0378-5173(98)00272-5
11. Buckton G, Darcy P. The use of gravimetric studies to assess the degree of predominant crystalline powders. Int J Pharm. 1995; 123(2): 265–271, https://doi.org/10.1016/0378-5173(95)00083-U
12. Kontny M, Zografi G. Sorption of water by solids In Physical characterization of pharmaceutical solids1995; Brittain HG, Ed. New York: Marcel Dekker; pp 386–418, DOI: 10.1002/jps.24160
13. Zografi G. States of water associated with solids Drug Dev Ind Pharm. 1988; 14(14): 1905–1926, https://doi.org/10.3109/03639048809151997
14. Dabrowski A. Adsorption From theory to practice. Adv Colloid Interface Sci. 2001; 93:135–224, https://doi.org/10.1016/S0001-8686(00)00082-8
15. Shete G, Kuncham S, Puri V, Gangwal RP, Sangamwar AT, Bansal AK. Effect of different “states” of sorbed water on amorphous celecoxib. J Pharm Sci. 2014; 103: 2033–2041. https://doi.org/10.1002/jps.24160
16. Briggner LE (Astra-Zeneca), Thermometric Application Note 22022, 1993.
17. Briggner LE, AstraZeneca, 2002
18. Hogan & Buckton Int. J. Pharm. 2000; 207: 57-64.
19. Dobry et al. J Pharm Innov. 2009; 4: 133-142.
20. Crowley et al. Drug Dev Ind Pharm 2007; 33: 909-926.
21. Brodka-Pfeiffer K., Häusler H., Grab P., Langguth P. conditioning following powder micronization: influence on particle growth of salbutamol sulfate. Drug Develop. Indust. Pharm. 2003; 29: 1077–1084, https://doi.org/10.1081/DDC-120025865
22. Vollenbroek J., Hebbink G., Ziffels S. Steckel H. Determination of low levels of amorphous content in inhalation grade lactose by moisture sorption isotherms. Int. J. Pharm. 2010; 395: 62–70. https://doi.org/10.1016/j.ijpharm.2010.04.035
23. Darcy P., Buckton G. The influence of heating/drying on the crystallization of amorphous lactose after structural collapse. Int. J. Pharm. 1997; 158: 157–164. DOI: 10.1021/js980387s
24. Guo Y., Shalaev E., Smith S. Physical stability of pharmaceutical formulations: solid-state characterization of amorphous dispersions Trends Anal. Chem. 2013; 49(705): 137–144. https://doi.org/10.1016/j.trac.2013.06.002
25. Sheokand S., Modi S., Bansal A. Dynamic vapor sorption as a tool for characterization and quantification of amorphous content in predominantly crystalline materials. J. Pharm. Sci. 2014; 103:3364–3376, https://doi.org/10.1002/jps.24160
26. Ward MD. Bulk crystals to surfaces combining X-ray diffraction and atomic force microscopy to probe the structure and formation of crystal interfaces. Chem Rev. 2001; 101(6): 1697-726. DOI: 10.1021/cr000020j
27. Fecht H. Defect-induced melting and solid-state amorphization. Nature. 1992; 356: 133–135, DOI: 10.1016/S0081-1947(08)60018-1
28. Font J., Muntasell J. and Cesari E. Amorphization of organic compounds by ball milling. Mater. Res. Bull. 1997; 32: 1691–1696, DOI: 10.1016/S0025-5408(97)00162-1.
29. Willart JF. and Descamps M. Solid state amorphization of pharmaceuticals Mol. Pharmaceutics. 2008; 5: 905–920, DOI: 10.1021/mp800092t
30. Muller T., Schiewe J., Smal R., Weiler C., Wolkenhauer M., Steckel H. Measurement of low amounts of amorphous content in hydrophobic active pharmaceutical ingredients with dynamic organic vapor sorption. Eur. J. Pharm. Biopharm. 2015; 92: 102–111, https://doi.org/10.1016/j.ejpb.2015.02.030
31. Mackin L., Zanon R., Park J., Foster K., Opalenik H., Demonte M. Quantification of low levels (<10%) of amorphous content in micronized active batches using dynamic vapor sorption and microcalorimetry. Int. J. Pharm. 2002; 231: 227– 236. https://doi.org/10.1016/S0378-5173(01)00881-X
32. Bates S., Zografi G., Engers D., Morris K., Crowley K. and Newman A. Analysis of amorphous and nanocrystalline solids from their X-ray diffraction patterns. Pharm. Res. 2006; 23: 2333– 2349, DOI: 10.1007/s11095-006-9086-2.