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91.
Effect of Glass Transition Temperature on the Stability of Lyophilized Formulations Containing a Chimeric Therapeutic Monoclonal Antibody 总被引:3,自引:0,他引:3
Purpose. The purpose of this study is to highlight the importance of knowing the glass transition temperature, Tg, of a lyophilized amorphous solid composed primarily of a sugar and a protein in the interpretation of accelerated stability data.
Methods. Glass transition temperatures were measured using DSC and dielectric relaxation spectroscopy. Aggregation of protein in the solid state was monitored using size-exclusion chromatography.
Results. Sucrose formulation (Tg ~ 59°C) when stored at 60°C was found to undergo significant aggregation, while the trehalose formulation (Tg ~ 80°C) was stable at 60°C. The instability observed with sucrose formulation at 60°C can be attributed to its Tg (~59°C) being close to the testing temperature. Increase in the protein/sugar ratio was found to increase the Tgs of the formulations containing sucrose or trehalose, but to different degrees.
Conclusions. Since the formulations exist in glassy state during their shelf-life, accelerated stability data generated in the glassy state (40°C) is perhaps a better predictor of the relative stability of formulations than the data generated at a higher temperature (60°C) where one formulation is in the glassy state while the other is near or above its Tg. 相似文献
92.
93.
94.
通过细胞融合技术,筛选出MAL-1和MAL-2两株抗莱氏支原体(A.Laidlawii,A.L)单克隆抗体(单抗)。通过SDS-PAGE和Western印迹法测得单抗相对应的抗原分子量均为67.46ku。用间接免疫荧光法(IFA)检测,单抗与细胞培养中另外3种常见污染的支原体和呼吸道肺炎支原体无交叉反应。将单抗用于检测支原体污染的细胞培养物,结果表明,此单抗能特异性地检出莱氏支原体。故可用其推断支原体污染途径,便于制定防治措施。 相似文献
95.
对雄性Wisiaf大鼠腹腔1次注射碘-13l, 注入活度分别为0.59×104Bq,2.37×104Bq, 4.34×104Bq, 8.23×104Bq, 碘-125注入活度分别为3.7×104Bq, 7.4×104Bq, 14.8×104Bq, 22.2×104Bq.碘-131诱发肿痛实际注入活度在2.37×104Bq以下,碘-125的为7.4×104以下.诱发的肿瘤以甲状腺肿瘤为主,其次为垂体肿瘤. 相似文献
96.
97.
用辣根过氧化物酶标记的AcLDL2培养小白鼠腹腔巨噬细胞,直观地显示了巨噬细胞表面AcLDL受体的存在,此受体只特异性的识别修饰的LDL,其识别作用与配体分子荷大量负电荷有关。 相似文献
98.
Institute of Biochemistry, Academy of Sciences of the Uzbek SSR, Tashkent. (Presented by Academician of the Academy of Medical Sciences of the USSR Yu. A. Pankov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 113, No. 2, pp. 168–170, February, 1992. 相似文献
99.
目的探讨冈比亚按蚊中肠抗原抗媒介免疫的作用,进一步研究抗媒介疫苗抗原.
方法解剖室内饲养的冈比亚按蚊雌蚊中肠,立即置于冷的pH 7.4 PBS溶液中,用SDS-PAGE方法获得分子质量为43
ku中肠蛋白抗原,皮下注射免疫大白兔3次,获得的免疫血浆膜饲冈比亚按蚊成蚊,与对照组比较,观察其对冈比亚按蚊死亡率和生殖率的影响.
结果膜饲免疫血浆的冈比亚按蚊的死亡率与对照组相比显著增高,死亡率增加56%;生殖率明显下降,实验组蚊虫平均产卵率为71.4个,对照组为88.1个,下降18.7%.
结论采用有效的方法分离蚊媒中肠的关键性抗原-中肠蛋白抗原可能成为抗蚊媒和其它抗媒介疫苗的靶抗原. 相似文献
100.
Several neurons from different nuclei give rise to descending spinal tracts and project to various levels in the spinal cord of goldfish, Carassius auratus. These were visualized by retrograde transport of horseradish peroxidase (HRP) administered to the bilaterally transected spinal cord at 6 levels, corresponding to 1st, 5th, 10th, 15th, 20th and 25gh segments of the vertebral column. As many as 16 brain nuclei or neuronal aggregations and the Mauthner cells project posteriorly up to the 20th spinal segment. Restricted neurons of the dorsolateral area in the nucleus preopticus magnocellularis and those of the ventromedial nucleus of the thalamus projected up to the 20th and 25th segments respectively. In the mesencephalon, the nucleus ruber and the nucleus of the medial longitudinal fasciculus revealed retrogradely labeled somata; the former extended up to the 20th segment, while the latter projected up to the 25th segment. The remaining descending projected neurons of the brain belonged to the rhombencephalon. The nucleus of the lateral lemniscus; anterior, magnocellular, descending and posterior divisions of the octaval nucleus: raphe nucleus; Mauthner cell and the neurons located adjacent to the trigeminal tract and those in the vicinity of the secondary gustatory tract sent their processes up to 20th segmental level. However, somata of the superior, medial and inferior divisions of the reticular nucleus and restricted neurons of the facial lobe extended up to 25th segmental level. The pattern of neuronal projections into the spinal cord suggests a topographic organization. 相似文献