精品久久久久久久换人妻,日韩人妻无码精品无码中文字幕,久久久久国产精品免费免费搜索,久久久久国产精品熟女影院

資訊中心NEWS CENTER

在發(fā)展中求生存,不斷完善,以良好信譽(yù)和科學(xué)的管理促進(jìn)企業(yè)迅速發(fā)展

首頁(yè)-技術(shù)文章-CEM用紫外監(jiān)測(cè)配件改進(jìn)了復(fù)雜多肽類的合成

企業(yè)新聞 技術(shù)文章

CEM用紫外監(jiān)測(cè)配件改進(jìn)了復(fù)雜多肽類的合成

更新時(shí)間:2012-06-29       點(diǎn)擊次數(shù):2336

INTRODUCTION

The AKR/Gross murine leukemia viruses (MuLV) are C-type retroviruses that cause the development of leukemia in AKR (H-2k) mice.1 Type-specific antiretroviral cytotoxic T-lymphocyte (CTL) responses have been reported that allow differentiation between infection by the AKR/Gross MuLV and other MuLV.1 A 10-mer derived from the C-terminal portion of the AKR/Gross MuLV CTL epitope has been used as a model “difficult” peptide for this study because it cannot be synthesized under standard conditions.2,3 UV monitoring of Fmoc deprotection allows the optimization of difficult syntheses. Typically, Fmoc removal is accomplished with piperidine, although other reagents such as piperazine may also be used. Piperidine reacts with the Fmoc-protected amino acid to remove the Fmoc group (which is converted to dibenzofulvene) yielding the free amine following decarboxylation (Figure 1). The dibenzofulvene can then react with piperidine to form the dibenzofulvene-piperidine adduct (DBF-pip).

Figure 1. Fmoc removal by piperidine.

 

The DBF-pip molecule shows a distinct UV absorbance at 301 nm that is easily discernible from the background absorbance of the other reagents present in the deprotection reaction.Thus, by monitoring the UV absorbance at 301 nm, the relative efficiency of a given deprotection reaction can be measured. When the UV spectrometer is connected to the Liberty/Liberty1, all liquid waste from the deprotection step flows through the UV flow cell, and the absorbance is measured. If the absorbance detected after the second (3 min) deprotection is above the set threshold, the deprotection is considered failed, and additional 3 minute deprotections are performed until either a passing value is obtained or a maximum number of deprotections has been reached. In theory, a difficult deprotection will correspond to a difficult coupling. When using the UV Monitoring Option, the coupling conditions can be modified (double coupling, extended coupling time, and/or capping) on failure to compensate for this difficulty.

 
 Liberty 全自動(dòng)流動(dòng)微波多肽合成系統(tǒng)

 


更多詳情,請(qǐng)培安公司:
:北京: 上海:  成都: 廣州:
: sales@pynnco.com  www.pynnco.com
 

SCROLL

Copyright©2025 培安有限公司 版權(quán)所有 All Rights Reserved    備案號(hào):京ICP備17026558號(hào)-1    總訪問(wèn)量:410051

技術(shù)支持:化工儀器網(wǎng)    管理登錄    sitemap.xml

亚洲av永久无码国产精品久久| 欧美激情肉欲高潮视频| 亚洲精品国产熟女久久久| 亚洲 自拍 色综合图第一页区 | 国产全肉乱妇杂乱视频| 野花香高清在线观看视频播放免费 | 日韩久久无码免费毛片软件| 国产精品久久久久久亚洲| 免费AV在线| 少妇人妻av| 亚洲精品成人片在线观看| 国产成A人亚洲精V品久久网| 爽爽爽男女爽视频免费| 免费无码又爽又刺激| 男女边吃奶边做边爱视频| 中文字幕av一区二区三区| 女人18毛片a级毛片免费视频| 亚洲成av人片在线观看无码麻豆 | 无码人妻久久一区二区三区| 女教师の爆乳bd在线观看| 精品无码一区二区三区在线 | 久久精品国产精品国产精品污| 国产精品扒开腿做爽爽爽a片| 欧美国产日韩a在线视频| 亚洲娇小与黑人巨大交| cao死你好紧好爽好湿视频男男| 成人免费在线电影| 特黄a级毛片免费视频| 国产精品久久久久jk制服| 亚洲 精品 综合 精品 自拍| 亚洲一区二区三区高清在线观看| 欧美三级a做爰在线观看| 少妇做爰免费视频网站| 日韩欧美aⅴ综合网站发布| 香蕉久久夜色精品国产| 久久人人爽人人爽人人片AV高清| 成人性生交a片免费看网站| 国产一区二区三区久久精品| 囯产精品一区二区三区线| 国产成人一区二区三区影院动漫| 色窝窝无码一区二区三区|