1、,電滲是CE的基本現(xiàn)象之一，它可以控制組分的遷移速度和方向，進(jìn) 而影響CE的分離效率和重現(xiàn)性,如何控制電滲流？,理論： 能影響電滲的因素都有可能用于電滲的控制 實(shí)際： 能理想地調(diào)節(jié)電滲而又不影響分離過(guò)程的控制方法目前 不多見(jiàn) 對(duì)于DNA分離及測(cè)序來(lái)說(shuō)，pH-8.3，常用管壁涂層（涂覆) 技術(shù).,化學(xué)涂覆,如聚丙烯酰胺、聚乙烯基吡咯烷酮涂層可在pH9-pH6以內(nèi)基本消除電滲,優(yōu)點(diǎn),抑制熔硅毛細(xì)管表面SiOH解離，修飾表面Zeta電勢(shì) 聚合物或硅烷化試劑的取代基覆蓋已離解的SiOH 增加了內(nèi)壁表面層附近溶液的粘度，涂層的厚度和密度都將影響到表面 層附近溶液的粘度，從而影響涂層的涂覆效果。 涂層壽命

2、長(zhǎng)，穩(wěn)定性好，分離效率高。,缺點(diǎn),化學(xué)鍵合的過(guò)程中涉及毛細(xì)管硅烷化和引發(fā)單體聚合兩步反應(yīng)，一方面受兩步反應(yīng)的轉(zhuǎn)化率影響，SiOH很難被完全屏蔽；另一方面，毛細(xì)管內(nèi)的聚合反應(yīng)很難控制，容易造成涂層的不均一性、不規(guī)整性，甚至阻塞毛細(xì)管。 價(jià)格昂貴。,物理涂覆,涂層制備過(guò)程簡(jiǎn)單易操作，涂覆過(guò)程可一步完成， 涂層可再生。這種涂層可以是中性的、帶正電荷的、也可以是吸附在帶正電的聚合物涂層表面轉(zhuǎn)而帶負(fù)電荷的。,優(yōu)點(diǎn),缺點(diǎn) 物理吸附涂層穩(wěn)定性不及化學(xué)鍵合涂層,用于DNA分離的聚合物,交聯(lián)聚合物: 交聯(lián)聚丙烯酰胺、瓊脂糖,非交聯(lián)聚合物,均聚物,poly-N-hydroxyethylacrylamide（PHE

3、A) 存在的問(wèn)題：,共聚物,a. 無(wú)規(guī)共聚物,理想的篩分介質(zhì)：高篩分能力、低粘度、自涂覆功能,poly (DEA-co-DMA) 聚 (N, N -二乙基丙烯酰胺- co -N, N - 二甲基丙烯酰胺） poly (AM-co-DMA) 聚(丙烯酰胺- co - N, N - 二甲基丙烯酰胺) poly (AA-co-AG) 聚(丙烯酰胺- co - -吡喃型葡萄糖) poly(AM-co-AAG) 聚(丙烯酰胺- co -葡糖酰丙胺) poly(NEEA-co-NMEA) 聚(乙氧基乙基丙烯酰胺- co -乙氧基甲基丙烯酰胺)等,b.嵌段共聚物 PEG-(CnF2n+1)2 末端帶有碳氟化

4、合物的聚乙二醇 PEO-PPO-PEO 低分子量的聚環(huán)氧乙烷和聚環(huán)氧丙烷的三嵌段共聚物 BEB/EBE 聚環(huán)氧乙烷和聚環(huán)氧丁烷的三嵌段共聚物等,C. 接枝共聚物 PAM-g-PNIPAM （聚丙烯酰胺-g- 聚N-異丙基丙烯酰胺) PNIPAM-g-PEO (聚N-異丙基丙烯酰胺-g- 聚環(huán)氧乙烷) PAM-g-PDMA （聚丙烯酰胺 -g- 聚N，N- 二甲基丙烯酰胺） PDMA-g-PMMA（聚N，N- 二甲基丙烯酰胺-g-聚甲基丙烯酸甲酯）等 存在的問(wèn)題：,共混聚合物,不同分子量的PEO分離ds 和ss DNA HEC，LPA等不同分子量的混合物也都能成功地對(duì)DNA分離或排序 存在的問(wèn)題

5、：,準(zhǔn)互穿網(wǎng)絡(luò)聚合物,Yanmei Wang,Dehai Liang, Jingcheng Hao, Dufei Fang, Benjamin Chu, Electrophoresis 2002, 23, 1460-1466,Mechanism of particle formation by inverse microemulsion polymerization of AM/AIBN system. M is monomer acrylamide; I is initiator; R is free radical.,Electrophoretic separation of DNA fr

6、agments generated on Big Dye TM Terminator Cycle Sequencing Standard with AmpliTaq FS under optimum experimental conditions: 2.5% IPNs, 200 V/cm and room temperature. A-track red, T-track blue, G-track green, and C-track black. Electrophoretic conditions were as follows: effective length 36 cm, tota

7、l length 41cm, 75-m-i.d., 365-m-o.d. anode buffer 1TTE; cathode buffer 1TTE/7M urea. The sample was injected at a constant electric field of 73 V/cm for 40 s.,Yanmei Wang, Dehai Liang, Q. Ying, B. Chu， Electrophoresis 2005, 26, 126-136,Preparation of quasi-IPN/GNPs composite matrices,quasi-IPN/GNPs復(fù)

8、合介質(zhì),TEM images of (A) GNPs20 (20 nm), (B) GNPs40 (40 nm), and (C) GNPs60 (60 nm) in water, and (D) GNPs40 (40 nm) in quasi-IPN3 polymer solution.,During the preparation of Au colloids, citrate acted as both a reducing agent and a capping agent to avoid aggregation of GNPs. The particle sizes of prep

9、ared GNPs could be controlled by the amount of trisodium citrate.,The full four-color (base C, T, A, G) electropherograms of Bigdye Terminator V 3.1 sequencing standard DNA sample by CE using 2.5% w/v quasi-IPN3/GNPs40-1 at 50. Sequencing conditions: effective/total length of bare fused-silica capil

10、laries, 50/61 cm; id/od, 75/365m; sequencing electric field strength, 150 V/cm; DNA electrokinetic injection, 41 V/cm for 30 s; anode buffer, 1TTE; cathode buffer, 1TTE/7M urea.,DNA sequencing by CE and data analysis,The partial four-color (base C, T, A, G) electropherograms of standard DNA sample u

11、sing 2.5% w/v quasi-IPN3/GNPs40-1 by CE at 50.,Electrophoresis, 2007, 28, 1072-1080.,Electrophoresis, 2007, 28, 2998-3007,中國(guó)發(fā)明專利：申請(qǐng)?zhí)枺?00610114099.3. 公開(kāi)號(hào)：CN1966719A,Electrophoresis, 2008, 29, 4637-4645.,quasi-IPN/functionalized multi-walled carbon nanotubes,Schematic representation of preparation of

12、MWNT-COOH, MWNT-Br and MWNT-PDMA via ATRP,Schematic representation of the formation of quasi-IPN/MWNT-PDMA double-network composite sieving matrix.,TEM images of (A) crude MWNTs in water and (B) MWNT-PDMA in quasi-IPN solution.,Resolution vs. base number in DNA sequencing by CE using quasi-IPN, HEC HEC-g-PAM-1 HEC-g-PAM-2 HEC-g-PAM-3 HEC-g-PAM-4,Electrophoresis, 2007, 28, 3223-3231.,HEC-g-PAM,Formation of HEC-g-PAM,Viscosity versus temperature for different HEC-g-PAM copolymers.,Schematic representa