The Stability and Shelf-Life of Liposome Encapsulated Hemoglobin: A Potential Blood Substitute

1987 ◽  
Vol 110 ◽  
Author(s):  
Alans Rudolph ◽  
Lewis P. Stratton ◽  
Wayne K. Knoll ◽  
Sandra Bayne ◽  
Frances Ligler

AbstractFor any viable blood substitute, questions of long-term storage and shelf-life must be addressed. Recently, we have made great progress in improving the stability of the blood substitute, liposome encapsulated hemoglobin (LEH). We have concentrated our efforts on protecting LEH in solution and in the long-term preservation of LEH by lyophilization. In particular, we have been able to retard and in some cases, reverse the oxidative process of metHb formation in solution by the addition of antioxidants such as NADH and glutathione. We have been able to regenerate Hb preparations with 60% metHb by the addition of 10 mM NADH and glutathione. In these preparations addition of these antioxidants results in a decrease of metHb levels from 62% to 15% over the course of 12.5 days at 4°C. We have also explored the use of protective solutes such as the disaccharide trehalose in the preservation of LEH in the freeze-dried state. Addition of increasing amounts of trehalose and other disaccharides results in the inhibition of lyophilization-induced fusion events and in the retention of hemoglobin within the unilamellar liposomal vesicles following rehydration.

2018 ◽  
Vol 20 (92) ◽  
pp. 29-33
Author(s):  
R. M. Sachuk ◽  
O. A. Katsaraba

For standardization, quality control, study of stability and establishment of storage conditions and terms of use, complex preclinical trials of the new development of PE “Biopharm” and the Experimental Station of Epizootology IVM NAAN – aerosol preparation “Yodozol” have been carried out. The methods of evaluation of a medicinal product applied to aerosols are used, which include: determination of changes in appearance, inspection of packaging for leakproofness, measurement of the percentage of contents of the package, the establishment of qualitative and quantitative indicators of active substances, and also the study of microbiological purity of the product. “Yodozol” is a light yellow liquid, 1 ml of which contains 5 mg of iodine and 10 mg of potassium iodide. The drug is used for the prevention and treatment of postnatal intrauterine infections in cows, pigs, sheep and goats (endometritis, pyrometers, cervicitis, vaginitis, delayed digestion caused by microorganisms sensitive to iodine), after obstetrics aid, cesarean section and postpartum sanitation of the uterus. The drug has antimicrobial, anti-inflammatory and analgesic effects, improves the proliferative processes of the genital organs, reduces the time for recovery of animals. The drug is used according to the guidelines, after its production livestock is used without restrictions. The shelf-life, which is the result of the test of the dasg according to the «stability» indicator, has been determined, which was performed under long-term storage in a place protected from light at a temperature range from + 5 ± 2 °С to + 25 ± 2 °С. The studies conducted after 6, 12, 24 and 30 months showed complete compliance of the quality indices with the declared standards when stored for 24 months in the temperature corridor from + 5 °C to + 20 °C. With an increase in storage temperature to + 25 °C or more, a slight quantitative decrease in the concentration of antimicrobial components occurred. In addition, with long-term storage of drugs, release of the contents from the cylinder became uneven and foam acquired a shade less than the saturation rate, increased microbiological contamination. Thus, according to the results of the study, the established shelf life of the preparation is 2 years at the recommended storage temperature from +5 to           +20 °С. All studies conducted on the stability of the aerosol intrauterine drug “Yodozol” were included in the registration materials of the medicinal product.


2019 ◽  
Vol 7 (40) ◽  
pp. 12518-12522 ◽  
Author(s):  
Yongqi Yang ◽  
Jianyu Xu ◽  
Yi Li ◽  
Guanghui Gao

A photochromic film that could be fast erased and possess long-term preservation ability has been designed, and could be used as rewritable paper.


2008 ◽  
Vol 1 (1) ◽  
pp. 67-78 ◽  
Author(s):  
M. Hafner ◽  
M. Sulyok ◽  
R. Schuhmacher ◽  
C. Crews ◽  
R. Krska

In this paper the stability and degree of epimerisation of six major ergot alkaloids at three different temperature levels (-20 °C, +4 °C and +20 °C) over periods of 18 hours and six weeks is reported for the first time. The behaviour of ergometrine, ergocornine, ergocristine, α-ergocryptine, ergosine and ergotamine was thoroughly studied in seven solvents which are employed for the preparation of calibrants and extraction mixtures, respectively. Moreover, the stability of the ergot alkaloids was tested in different cereal extracts (rye, wheat, barley, oats) for 1, 2 and 6 days. Of the toxins tested, the ergopeptide-type toxins ergosine, ergotamine, ergocornine, α-ergocryptine and ergocristine showed similar behaviour patterns. The simple lysergic acid derivative ergometrine was more stable and showed hardly any epimerisation to ergometrinine, with the sum of both epimers remaining constant in all seven solvents. The ergopeptides tested show variable epimerisation tendencies, and were also less stable during six weeks at 20 °C. Ergosine showed the highest degree of epimerisation (43% after 6 weeks at 20 °C). In general, the order of epimerisation promotion was methanol/dichloromethane > acetonitrile/buffer > extraction mix > stabilising solution > acetonitrile >> chloroform. Long-term storage at room temperature can only be carried out in chloroform, which showed no epimerisation for all toxins even at 20 °C and also kept the sum of R and S forms constant, which indicates no formation of aci-epimers or other degradation products. Long-term storage of ergot alkaloids in acetonitrile, the most convenient solvent with respect to HPLC analysis, should be carried out at temperatures of -20 °C or below. The constant epimer ratio of all ergot alkaloids in the extraction mixture acetonitrile/ammonium carbonate buffer (200 mg/l; 92:8, v/v) during an HPLC run (18 hours) demonstrates the stability of the toxins in this extraction mixture.


2019 ◽  
Vol 974 ◽  
pp. 187-194 ◽  
Author(s):  
Nikolay V. Lyubomirskiy ◽  
Tamara A. Bakhtina ◽  
Alexander S. Bakhtin ◽  
Sergey I. Fedorkin

This paper presents the lime binding forced carbonate-hardening materials properties formation study and determins the stability of these properties during long-term storage and use under normal conditions. The tests showed these materials stability properties over time, confirming the strength and density growth of the test samples after long storage due to the calcium hydroxide recrystallization completion into calcium carbonate processes. Also, the results of the samples carbonate hardening study under natural conditions during 18 months are presented. An efficiency assessment of forced carbonate hardening as one of the methods of recycling technogenic CO2 in order to reduce its emissions in the atmosphere, and, in the result, to obtain high-quality construction materials has been made.


2020 ◽  
Vol 176 ◽  
pp. 03021
Author(s):  
Natalia Zavorokhina ◽  
Natalia Pankratyeva ◽  
Nadezhda Goncharova

Nowadays in the context of innovative development the bread intended for long-term storage is necessary in hard-to-reach areas of Sverdlovsk region, participants of expeditions, workers of logging, geological parties, etc. Taking into account the constant demand for such products, it is necessary to develop new approaches to their creation.The aim of the study was the development of long-term storage bread from wheat flour, preserving consumer characteristics throughout the shelf life.The synergism of betulin,nisin and ascorbic acid was studied for the first time when they are used together to inhibit potato bread disease (hereinafter CBH). It is proved that the use of additives, including 0.015% nisin together with 0.005% betulin to the mass of flour increases the shelf life of wheat bread up to 7 days since betulin inhibits CBH, nisin inhibits the development of mold under pH conditions in the range of 5.5-6.5.For the first time, a technique is proposed for producing betulin nanosuspension with a high degree of dispersion. The effect of betulin nanosuspension with emulsifiers of calcium lactylate, polyglycerol fatty acid esters, lecithin on the inhibition of CBH and an increase in the shelf life of wheat bread was studied.


Heliyon ◽  
2019 ◽  
Vol 5 (9) ◽  
pp. e02431 ◽  
Author(s):  
Maria A. Karlsson ◽  
Maud Langton ◽  
Fredrik Innings ◽  
Bozena Malmgren ◽  
Annika Höjer ◽  
...  

2020 ◽  
Vol 20 (11) ◽  
pp. 6855-6861
Author(s):  
Wooram Kim ◽  
Mijeong Park ◽  
Jong-Ki Jeon ◽  
Youngmin Jo

Dinitramide anion [−N(NO2)2] salt composed of resonance structure is a plausible oxidizing agents, as efficient propellant. Among them, guanidinium dinitramide (GDN) is an organic compound improving the stability against moisture, as well long term storage. An additional advantage composed guanidinium ion is the reaction efficient via the decomposed by-product during pyrognostics, maximum yield of 99%. The types of GDN (GDN-I, II, III, IV, V) were synthesized using several starting material such as guanidine acetate, chloride, carbonate, nitrate and sulfate under hydrodeprivation. In this work, the intermediates formed in these processes were closely identified and their thermal properties, and chemical structure were examined. The absorption peaks by Fourier transform infrared (FT-IR) were found guanidinium infrared frequencies (3452, 3402, 3354, 3278, 1642 cm−1) and dinitramide infrared frequencies (3208, 1570, 1492, 1416, 1337, 1179, 1000 cm−1). The activation energy of GDN samples were obtained Ea = 53.26 Kcal/mole (GDN-I), 50.94 Kcal/mole (GDN-II), 52.34 Kcal/mole (GDN-III), 62.19 Kcal/mole (GDN-IV), 55.32 Kcal/mole (GDN-V) from exothermic at over 153°C.


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