Subscribe to the gold package and get unlimited access to Shamra Academy
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
1302
0 11
0
(
0
)
Added by
Damascus University ورقة بحثية
Publication date
2014
fields
Pharmacy
and research's language is
العربية
Authors
محمد أمين محمد( باحث )
Created by
Shamra Editor
Ask ChatGPT about the research
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
rate research
Read More
Green tomato fruits of different studied hybrids such as, Amal, Steel,
Tartila, and 2-75/96, which had been grown in a greenhouse at Abi- Jarash
Farm were picked up and stored at temperatures of 12 c and 20 c for 29 days.
The fruits, which were st
ored at 12 c had been transferred to 9 cْ, and then
stored for an additional period of two weeks. The chemical composition of the
stored fruits was evaluated, which included: acidity percentage, total soluble
solids, and the quantity of vitamine C. The ratio of fruit weight loss during
storage was studied as well.
Pastrami, manufactured from beef and abdominal fat and of a ratio of 3 meat to 1 fat,
was stored under refrigeration at (4±2 °C) and storage times (0, 15, 30, 60, 120, and 180
days). The effects of storage times on the most important chemical, micr
obiological and
sensory properties of pastrami were investigated.
The results of chemical analyzes showed that the studied pastrami conformed to the
Syrian Standards in terms of the proportion of salt and fat content, and it nearly conformed
to the standards in terms of humidity. The results also showed a slight decrease in the
percentage of moisture, fat and protein, and an increase in each of the acidity, proportion of
total volatile nitrogen, soluble nitrogen and peroxide value in pastrami with the progress of
the storage period at the temperature degree (4±2 °C). The microbial tests showed that
pastrami is free from some sickening organisms especially salmonella and E. coli. It also
showed that the census of the aerobic bacteria, yeasts and fungi was within the limits of the
Syrian standards. The results showed deterioration in the microbial properties of stored
pastrami with the progress of time; pastrami became invalid from a microbial point of
consumption after two months of storage as a result of the big number of aerobic bacteria,
yeasts and fungi. The sensory tests showed deterioration in the organoleptic characteristics
of storage with the progress of time, the deterioration was clear after two months of
storage; pastrami became unacceptable in terms of taste, color, smell and texture.
The manifestation of the self-action potential for charge carrier in system consisted of three spatially heterogeneous layers is investigated theoretically. The expressions for the self-action potential energy of a test charge placed in a central la
yer of the three-layer structures. The self-action potential energy of electron- hole and Wannier – Mott exciton are calculated numerically. The self-action potential energy of electron- hole and Wannier – Mott exciton are plotted as a function.
This research aims to decrease the cost of last production stages
through decreasing the cost of potential casing repair by avoiding the
problems that casing string may be exposed to. Such problems are
caused by the temperature effect of salt dril
ling fluids as well as other
fluids normally existed in the annular behind casing at the nonecemented
intervals.
In this research a study effect of absorbed surface shape for solar air collector
(Flat V-Corrugated ,Sinusoidal Wave-Corrugated ,Rectangular-Corrugated) titled to the horizontal by an angle(30) on forced heat transfer and skin friction coefficient
by Fluent Numerical Program at constant solar heat flax (530W/m2) with Reynold’s number (5000≤Re≤8000). The government equation (mass, momentum and energy) are using Finite Volume by (Fluent 6.3) software for considering steady state, two dimensional and turbulent flow. The results show that the different between inlet and outlet air temperature is(13.65oC) and best heat transfer coefficient enhancement is(63%) for (V-Corrugated plate) compared with the flat plate at (Re=8000). Also the results show that the maximum skin friction coefficient is occurred at (V-Corrugated) Cf=0.22 at (Re=8000).
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
