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Thermal analysis of amorphous lactose and α-lactose monohydrate

α-

Analyse thermique de lactose amorphe et de lactose α monohydrate

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Dairy Science & Technology

Abstract

It is common to find that some of the lactose in dairy powders and pharmaceutical tablets is present in the unstable amorphous state. If stored at inappropriate temperatures and humidities amorphous lactose is susceptible to crystallization. The integration of thermal gravimetric analysis (TGA) with single differential thermal analysis (SDTA) provided a descriptive method for a sequential and direct determination of surface water, water of crystallization and amorphous lactose in a single analysis on one sample. Peaks and mass changes on the TGA/SDTA thermograms characteristic of surface water, water of crystallization and amorphous lactose were identified. The content of water of crystallization was used to estimate α-lactose monohydrate. The loss of surface water was indicated on the TGA/SDTA thermograms as weight loss between 40 and 130 °C and the loss of water of crystallization occurred at 153 °C. Amorphous lactose was indicated by an exothermic crystallization peak at 174 °C. The area under the exothermic crystallization peak was linearly related to the proportion of the amorphous lactose in mixtures with α-lactose monohydrate (r = 0.989). This work presented the TGA/SDTA thermograms of lactose samples containing some crystalline forms of lactose and amorphous lactose. The study compared the methods for determining surface water and total water content of lactose accepted by official bodies worldwide with the TGA/SDTA approach. The potential of new methods for qualitatively detecting the amorphous and crystalline forms of lactose by thermochemistry and Fourier transform infra-red (FT-IR) was also explored and compared.

Abstract

(TGA) / (SDTA) TGA/SDTA α- TGA/SDTA 40–130 °C 153 °C 174 °C α-(r = 0.989) TGA/SDTA TGA/SDTA

Résumé

Généralement une partie du lactose dans les poudres laitières et les comprimés pharmaceutiques se trouve à l’état amorphe instable. S’il est conservé à des températures et humidités inappropriées, le lactose amorphe peut cristalliser. Le couplage de l’analyse thermogravimétrique (TGA) avec l’analyse thermique différentielle (SDTA) a fourni une méthode descriptive pour la détermination séquentielle et directe de l’eau de surface, de l’eau de cristallisation et du lactose amorphe d’un échantillon en analyse. Les pics et les changements de masse sur les thermogrammes TGA/SDTA caractéristiques de l’eau de surface, de l’eau de cristallisation et la teneur en lactose amorphe ont été identifiés. La teneur en eau de cristallisation a été utilisée pour estimer le lactose α monohydrate. La perte d’eau de surface se traduisait sur les thermogrammes TGA/SDTA par la perte de poids entre 40 et 130 °C, et la perte d’eau de cristallisation avait lieu à 153 °C. Le lactose amorphe était indiqué par un pic de cristallisation exothermique à 174 °C. La surface sous le pic de cristallisation exothermique était linéairement reliée à la proportion de lactose amorphe dans les mélanges avec lactose α monohydrate (r = 0,989). Ce travail présente les thermogrammes TGA/SDTA d’échantillons de lactose contenant quelques formes cristallines de lactose et de lactose amorphe. L’étude a comparé les méthodes pour déterminer les teneurs en eau de surface et en eau totale du lactose acceptées par les organismes officiels internationaux avec l’approche TGA/SDTA. Le potentiel de nouvelles méthodes pour détecter qualitativement les formes amorphes et cristallines du lactose par thermochimie et spectroscopie infrarouge à transformée de Fourier a également été exploré et comparé.

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References

  1. British Pharmacopoeia (BP), Medicinal and pharmaceutical substances, The Stationery Office, Great Britain, 1, 2001, pp. 23–20 to 23–23.

    Google Scholar 

  2. Brown H.T., Pickering S.U., Thermochemistry of chemistry hydrolysis, J. Chem. Soc. 71 (1897) 783–795.

    CAS  Google Scholar 

  3. Buckton G., Yonemochi E., Hammond J., Moffat A., The use of near infra-red spectroscopy to detect changes in the form of amorphous and crystalline lactose, Int. J. Pharm. 168 (1998) 231–241.

    Article  CAS  Google Scholar 

  4. Elmonsef Omar A.M., Roos Y.H., Glass transition and crystallization behaviour of freeze-dried lactose-salt mixtures, Lebensm. Wiss. Technol. 40 (2007) 536–543.

    Google Scholar 

  5. FAO/WHO, Methods of analysis for sugars, in: Codex Alimentarius, CAC/RM 1/8-1969, FAO/WHO, Rome, 1969, p. 9.

    Google Scholar 

  6. FAO/WHO, Codex standard for sugars, in: Codex Alimentarius, Codex STAN 212-1999 (Amd. 1-2001), FAO/WHO, Rome, 2001, pp. 1–5.

    Google Scholar 

  7. Fernandez-Martin F., Morais F., Olano A., Thermal behaviour of lactose, in: Linko P., Malkki Y., Olkku J., Larinkari J. (Eds.), Food Process Engineering, volume 1: Food Processing Systems, Applied Science Publishers, Barking, Essex, UK, 1980, pp. 523–529.

    Google Scholar 

  8. Figura L.O., The physical modification of lactose and its thermoanalytical identification, Thermochim. Acta 222 (1993) 187–194.

    Article  CAS  Google Scholar 

  9. Figura L.O., Epple M., Anhydrous α-lactose: a study with DSC and TXRD, J. Therm. Anal. 44 (1995) 45–53.

    Article  CAS  Google Scholar 

  10. Findlay A., Thermochemistry, in: Findlay A. (Ed.), Physical Chemistry, Longman, London, UK, 1954, pp. 186–198.

    Google Scholar 

  11. Fitzpatrick J.J., Hodnett M., Twomey M., Cerqueira P.S.M., O’Flynn J., Roos Y.H., Glass transition and the flowability and caking of powders containing amorphous lactose, Powder Tech. 178 (2007) 119–128.

    Article  CAS  Google Scholar 

  12. Fix I., Steffens K.J., Quantifying low amorphous or crystalline amounts of alphalactose-monohydrate using X-ray powder diffraction, near-infrared spectroscopy, and differential scanning calorimetry, Drug Dev. Ind. Pharm. 30 (2004) 513–523.

    Article  CAS  Google Scholar 

  13. Gabbott P., Clarke P., Mann T., Royall P., Shergill S., A high-sensitivity, high-speed DSC technique: Measurement of amorphous lactose, Am. Lab. 35 (2003) 17–18, 20, 22.

    CAS  Google Scholar 

  14. Gombas A., Szabo-Revesz P., Kata M., Regdon Jr G., Eros I., Quantitative determination of crystallinity of α-lactose monohydrate by DSC, J. Therm. Anal. Calorim. 68 (2002) 503–510.

    Article  CAS  Google Scholar 

  15. 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. 174 (1998) 243–252.

    Article  CAS  Google Scholar 

  16. Harjunen P., Lehton V.P., Koivisto M., Levonen E., Paronen P., Jarvinen K., Determination of amorphous content of lactose samples by solution calorimetry, Drug Dev. Ind. Pharm. 30 (2004) 809–815.

    Article  CAS  Google Scholar 

  17. Hogan S.E., Buckton G., The quantification of small degrees of disorder in lactose using solution calorimetry, Int. J. Pharm. 207 (2000) 57–64.

    Article  CAS  Google Scholar 

  18. Hogan S.E., Buckton G., The application of near infrared spectroscopy and dynamic vapor sorption to quantify low amorphous contents of crystalline lactose, Pharm. Res. 18 (2001) 112–116.

    Article  CAS  Google Scholar 

  19. Holsinger V.H., Lactose, in: Wong N.P., Jenness R., Keeney M., Marth E.H. (Eds.), Fundamentals of Dairy Chemistry, Van Nostrand Reinhold, New York, USA, 1988, pp. 279–342.

    Google Scholar 

  20. Hudson C.S., Brown F.C., The heats of solution of the three forms of milk-sugar, J. Am. Chem. Soc. 30 (1908) 960–971.

    Article  CAS  Google Scholar 

  21. International Dairy Federation (IDF), Dried milk and dried cream: determination of water content: Standard 26A, International Dairy Federation, Belgium, 1993.

    Google Scholar 

  22. Itoh T., Satoh M., Adachi S., Differential thermal analysis of α-lactose hydrate, J. Dairy Sci. 60 (1977) 1230–1235.

    Article  CAS  Google Scholar 

  23. Jones J.M., McLachlan T., The determination of moisture by the volatile solvent method, Analyst 52 (1927) 383–387.

    Article  CAS  Google Scholar 

  24. Jorissen W.J., Van de Stadt E., Ueber die Bindungswärme des Krystallwassers von organischen Verbindungen, J. Prakt. Chem. 51 (1894) 102–106.

    Article  Google Scholar 

  25. Kirk J.H., Dann S.E., Blatchford C.G., Lactose: A definitive guide to polymorph determination, Int. J. Pharm. 334 (2007) 103–114.

    Article  CAS  Google Scholar 

  26. Lide D.R., CRC Handbook of Chemistry and Physics, CRC Press, USA, 2004.

    Google Scholar 

  27. Listiohadi Y.D., Modification of sugars by extrusion, MSc Honours Thesis, University of Western Sydney Hawkesbury, Richmond, NSW, Australia, 2000.

    Google Scholar 

  28. Listiohadi Y.D., The caking of lactose, Ph.D. Thesis, University of Western Sydney, Richmond, NSW, Australia, 2004.

    Google Scholar 

  29. Listiohadi Y.D., Hourigan J.A., Sleigh R.W., Steele R.J., Properties of lactose and its caking behaviour, Aust. J. Dairy Technol. 60 (2005) 33–52.

    CAS  Google Scholar 

  30. Lloyd R.J., Chen X.D., Hargreaves J.B., Glass transition and caking of spray-dried lactose, Int. J. Food Sci. Technol. 31 (1996) 305–311.

    Article  CAS  Google Scholar 

  31. Magie W.F., The specific heats of certain organic solids, Phys. Rev. 16 (1903) 381–382.

    Google Scholar 

  32. Magie and Hudson, Princeton Univ. Bull. April (1902). As cited by Hudson and Brown (1908), see above [20].

  33. Nakanishi K., Infrared Absorption Spectroscopy, Nankoudou Press, Tokyo, 1960.

    Google Scholar 

  34. Newell H.E., Buckton G., Butler D.A., Thielmann F., Williams D.R., The use of inverse phase gas chromatography to measure the surface energy of crystalline, amorphous, and recently milled lactose, Pharm. Res. 18 (2001) 662–666.

    Article  CAS  Google Scholar 

  35. Norris K.P., Greenstreet J.E.S., Infra-red absorption spectra of casein and lactose, Nature 181 (1958) 265–266.

    Article  CAS  Google Scholar 

  36. Roetman K., Methods for the quantitative determination of crystalline lactose in milk products, Neth. Milk Dairy J. 35 (1981) 1–52.

    Google Scholar 

  37. Roetman K., Buma T.J., Temperature dependence of the equilibrium β/α ratio of lactose in aqueous solution, Neth. Milk Dairy J. 28 (1974) 155–165.

    CAS  Google Scholar 

  38. Roetman K., Van Schaik M., The β/α ratio of lactose in the amorphous state, Neth. Milk Dairy J. 29 (1975) 225–237.

    CAS  Google Scholar 

  39. Roos Y., Karel M., Crystallization of amorphous lactose, J. Food Sci. 57 (1992) 775–777.

    Article  CAS  Google Scholar 

  40. Roos Y., Karel M., Effects of glass transitions on dynamic phenomena in sugar containing food systems, in: Blanshard J.M.V., Lillford P.J. (Eds.), The Glassy State in Foods, Nottingham University Press, Leicestershire, UK, 1993, pp. 207–222.

    Google Scholar 

  41. Saunders M., Podluii K., Shergill S., Buckton G., Royall P., The potential of high speed DSC (Hyper-DSC) for the detection and quantification of small amounts of amorphous content in predominantly crystalline samples, Int. J. Pharm. 274 (2004) 35–40.

    Article  CAS  Google Scholar 

  42. Savolainen M., Jouppila K., Pajamo O., Christiansen L., Strachan C., Karjalainen M., Rantanen J., Determination of amorphous content in the pharmaceutical process environment, J. Pharm. Pharmacol. 59 (2007) 161–170.

    Article  CAS  Google Scholar 

  43. Schuck P., Dolivet A., Lactose crystallization: Determination of α-lactose monohydrate in spray-dried dairy products, Lait 82 (2002) 413–421.

    Article  CAS  Google Scholar 

  44. United States Pharmacopeia (USP), The National Formulary: USP 23, NF 18 United States Pharmacopeial Convention, Washington, 1995, pp. 2257–2258.

    Google Scholar 

  45. Van Leverink J., Extrusion process for the preparation of anhydrous stable lactose, U.S. Patent No. 4 280 997, 1981.

Download references

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Listiohadi, Y., Hourigan, J.A., Sleigh, R.W. et al. Thermal analysis of amorphous lactose and α-lactose monohydrate. Dairy Sci. Technol. 89, 43–67 (2009). https://doi.org/10.1051/dst:2008027

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