近年来,单克隆抗体(mAb) 已成为可满足多种疾病治疗需求的主要生物制药产品。这些经特别设计的抗体具有特定基因构成,能够更好地靶向病原。在这些抗体的开发过程中,Protein A 和Protein G 分析型亲和色谱柱可用于测定各种细胞培养上清液中的抗体滴度或浓度,以选出高产量的克隆。惰性聚合物Monolith 可用作Protein A 和Protein G 色谱柱的担体。两种色谱柱都对抗体具有较高亲和性,因此它们能够仅结合细胞培养上清液中的抗体。本应用简报主要介绍Agilent Bio-Monolith Protein G 色谱柱。该色谱柱专为获得高速、高载样量而设计。文中给出的数据表明它同时具备线性与特异性。线性分析结果表明色谱柱在细胞培养上清液mAb 准确定量分析中的超高性能。此外,使用寿命分析数据能够反映色谱柱具有高重现性、较长寿命以及出色的稳定性与低反压。Bio-Monolith Protein G 色谱柱是Bio-Monolith Protein A 色谱柱的补充产品,可为单克隆抗体滴度测定提供更多选择。
Bio-Monolith Protein A 色谱柱经过微小修饰减少了堵塞,极少或没有出现宿主细胞蛋白的非特异性结合。这些色谱柱表现出极小的残留和出色的使用寿命,即使在进样 750 次细胞培养上清液原液后,峰形也几乎没有变差。这为快速、准确地测定抗体滴度水平提供了出色的工具,适用于一次筛选数百个样品。
摘要:利用电子鼻技术快速区分酸羊奶的发酵菌种。通过电子鼻采集不同酸羊奶挥发成分的响应值,然后利用主成分分析(pri nci pal com ponent anal ysi s,PCA)、Fi sher线性判别分析(fi sher l i near di scri m i nant anal ysi s,FLDA)以及BP神经网络(back propagati on neural netw ork,BP-NN)分析进行判别,建立基于电子鼻技术区分酸羊奶发酵菌种的方法。结果表明,FLD A及PCA都能够区分出不同菌种发酵的酸羊奶,FLD A区分效果优于PCA。利用FLDA和BP-NN分析预测酸羊奶发酵菌种类别的正确率分别为100. 0%和98. 4%。因此,利用电子鼻快速区分酸羊奶的发酵菌种是可行的。关键词:电子鼻;酸羊奶;乳酸菌;多元分析
Here we report the development of a class of structurally versatile cationic lipopolyamines designed specifically for delivery of siRNA which show high levels of target transcript knockdown in a range of cell types in vitro. A primary benefit of these lipids is the ease with which they may be covalently modified by the addition of functional molecules. For in vivo applications one of the core lipids (Staramine) was modified with methoxypolyethylene glycols (mPEGs) of varying lengths. Upon systemic administration, PEGylated Staramine nanoparticles containing siRNA targeting the caveolin-1 (Cav-1) transcript caused a reduction of the Cav-1 transcript of up to 60%, depending on the mPEG length, specifically in lung tissue after 48 h compared to treatment with non-silencing siRNA. In addition, modification with mPEG reduced toxicity associated with intravenous administration. The ability to produce a high level of target gene knockdown in the lung with minimal toxicity demonstrates the potential of these lipopolyamines for use in developing RNAi therapeutics for pulmonary disease.