Numerous techniques have been developed to prepare immunoliposomes based on the nucleophilic reactivity of free amine groups of proteins or peptides. One of the most popular and commonly used methods is to covalently couple free carboxylic groups to primary amines through activation of the carboxyl groups with EDC (1-ethyl-3-[3-dimethylaminopropyl] carbodiimide). EDC, which is a so-called zero-length crosslinking agent, reacts with the carboxyl to form an amine reactive intermediate (O-acylisourea). The produced O-acylisourea can be easily displaced by nucleophilic attack from the primary amino groups in the reaction mixture. However, this intermediate is unstable and hydrolyzed in aqueous solutions. In order to prevent the intermediate hydrolysis, sulfo-NHS (N-hydroxysulfosuccinimide) is added to EDC to produce a significantly more stable and more soluble active intermediate (NHS ester).
Consequently, the immunoliposomes are prepared by a two-step coupling procedure: first, activating the free carboxyl group of the linker lipid incorporated in the liposomes with EDC and sulfo-NHS, and then covalently conjugating the antibodies to the lipids through displacement of sulfo-NHS groups by antibody amines, as depicted below. EDC/sulfo-NHS coupling reactions are highly selective and highly efficient, and the biological activity of the protein or peptide is preserved.
ImmunoFluor™-Succinyl is a PEGylated product. For other amine reactive (PEGylated and non-PEGyalated products) and also ImmunoFluor™ products suitable for other types conjugation methods see here.
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转录的只是插入的片断，怎么会跟模板一样大呢，一般情况下应该比模板小多了。我都是跑电泳，严格来说应该跑变性的；嫌麻烦可以非变性，快速（防止RNA降解）十分钟即可；抛出来的带会有两条，上面大的是模板，下面一条比较亮的是RNA，那么你的转录就 成功了。
PCR第一个步骤如果没记错的话应该叫“变性”， PCR的话是不需要解旋酶的，直接利用DNA的高温变性特性，在高温下，使氢键断开，DNA双链恢复为单链。 （还有解旋酶好像是解除双螺旋的结构，是一种拓扑异构酶，对于氢键的打开没有贡献吧
1.模板提取（一般为RNA）：Trizol、氯仿、异丙醇、无水乙醇、DEPC处理水
2.模板浓度测定：分光光度计或NanoDrop
3.逆转录：逆转录试剂盒（或者一步法试剂盒），这一步可以用普通PCR做，也可以用水域做。
4.荧光定量PCR试剂：通常有用SYBR Green Mix做的，但是这里建议你用EvaGreen做，灵敏度和平行性都要好于SYBR Green，并且如果你那是ABI或者Stratagene的PCR如果用SYBR Green还需要加一步Rox很麻烦。
5.其他：除了以上的那些还需要离心管、PCR管或板（Axygen反应比较好）、移液枪等，暂时就想到这么多。
逆转录（reverse transcription）是以RNA为模板合成DNA的过程，即RNA指导下的DNA合成。此过程中，核酸合成与转录（DNA到RNA）过程与遗传信息的流动方向（RNA到DNA）相反，故称为逆转录。逆转录过程是RNA病毒的复制形式之一，需逆转录酶的催化。 逆转录过程的揭示是分子生物学研究中的重大发现，是对中心法则的重要修正和补充。人们通过体外模拟该过程，以样本中提取的mRNA为模板，在逆转录酶的作用下，合成出互补的cDNA，构建cDNA文库，并从中筛选特异的目的基因。该方法已成为基因工程技术中最常用的获得目的基因的策略之一。
