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Register a new userThe Effect of Storage Temperature on the Surface free Energy of Spray Dried Lysozyme Powders
تأثير حرارة التخزين في طاقة السطح الحرة لمساحيق الليزوزيم المجفف بالإرذاذ
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Damascus University ورقة بحثية
Publication date
2014
fields
Pharmacy
and research's language is
العربية
Authors
محمد أمين محمد( باحث )
Created by
Shamra Editor
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خلفية البحث و هدفه: تُستخدم تقنيات التجفيف بالإرذاذ في تحضير مساحيق استنشاقية للإنزيمات و البروتينات دون تمسخها. يستفاد من معطيات طاقة السطح الحرة لهذه المساحيق بتقليل الزمن اللازم لتطوير مستحضراتها و تحسين جودة مناشق المساحيق. يمكن أن تتغير طاقة السطح الحرة لهذه المساحيق البروتينية الاستنشاقية، خلال التخزين، و من ثم تؤثر في أدائها. و تؤثر عوامل عدة في مدى هذا التغير. و لكن درجة حرارة التخزين هي العامل الحدي. مواد البحث و طرائقه: طُورت طريقة تجفيف بالإرذاذ لتحضير مساحيق استنشاقية لليزوزيم مجففة بالإرذاذ (كنموذج للمساحيق البروتينية الاستنشاقية). استخدم الاستشراب الغازي العكوس لقياس طاقة السطح الحرة للمساحيق المحضرة قبل التخزين و بعده لكي توضح تأثير حرارة التخزين في طاقة السطح الحرة. و نظراً إلى البنية الفراغية البروتينية الضعيفة قد تتمسخ بدرجة حرارة التخزين، استخدمت تقنية المسح الحراري التفاضلي (DSC) و فحوص النشاط البيولوجي لتقييم سلامة البنية الفراغية لليزوزيم بعد التخزين في درجات حرارة مختلفة. النتائج: تنقص زيادة درجة حرارة التخزين لكل من مكونات السطح اللاقطبية بنحو 12 % و القطبية بنحو 31% (ANOVA: P < 0.001) للمساحيق الاستنشاقية لليزوزيم المجففة بالإرذاذ. و هذا التناقص في مكونات السطح القطبية يؤدي إلى تناقص في قلوية السطح. يمكن أن تعزى هذه التغيرات في طاقات السطح لتكدس جزيئات اليزوزيم المتمسخة إلى جانب بعضها بعضاً من خلال المناطق الغنية بالإلكترونات الموجودة على سطح المساحيق. الاستنتاج: ينصح بتخزين المساحيق البروتينية في درجة حرارة منخفضة، على سبيل المثال 5 درجة مئوية، و ذلك لمنع أي تغير في طاقة السطح الحرة التي تعد عاملاً ذا تأثير حدي في أداء هذه المساحيق.
Background & Objective: Spray drying techniques are used to produce inhaled powders of enzymes and proteins without denaturation. The surface free energy data of these powders is used to reduce the time of formulation development. During storage, the surface free energy of the inhaled protein powders could change and so their performance will be affected. Many factors affect the limit of this change. Storage temperature is the critical factor. Material& methods: A spray drying method was optimized to prepare inhaled spray dried lysozyme powders. Inverse gas chromatography was utilized to measure the surface free energy of the prepared powders pre and post-storage to detect the effect of storage temperature on the surface free energy. Differential Scanning Calorimetry and biological activity tests were used to evaluate the integrity of lysozyme conformation after storage at different storage temperature. Results: Increasing the storage temperature decreased both dispersive and specific surface components of the spray-dried lysozyme powders significantly (ANOVA: P < 0.001) up to 12% and up to 31 % after storage for one year at 40 °C, respectively. The overall decrease in the polar components resulted in a reduction of the surface basicity. These decreases in the surface energetics would be due to the aggregation of denatured lysozyme molecules at the powder surface via hydrophobic regions rich with electrons. The same results were found after storage for one year at room temperature, but the extents of changes were smaller. Conclusion: It is advisable to store protein powders at 5°C to inhibit the changes in their surface free energy which is the crucial factor affecting their performance.
References used
Mumenthaler M, Hsu CC, Pearlman R. Feasibility study on spray-drying protein pharmaceuticals – Recombinant human growth hormone and tissue-type plasminogen-activator. Pharm. Res. 1994, 11: 12-20
Broadhead J, Rouan SKE, Rhodes CT. The spray drying of pharmaceuticals drug. Dev. Ind. Pharm. 1992, 18: 1169-1206
Johnson KA. Preparation of peptide and protein powders for inhalation. Adv. Drug Deliver. Rev. 1997, 26: 3- 15
Maltesen MJ, Bjerregaard S, Hovgaard L, Havelund S, Van de Weert M. Quality by design – Spray drying of insulin intended for inhalation. Eur. J. Pharm. Biopharm. 2008, 70: 828-838
Lee SH, Heng D, Kiong NW, Chan HK, Tan RBH. Nano spray drying: A novel method for preparing protein nanoparticles for protein therapy. Int. J. Pharm. 2011, 403: 192-200
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