電(dian)(dian)(dian)泳(yong)儀(yi)是實現(xian)(xian)電(dian)(dian)(dian)泳(yong)分(fen)(fen)析的儀(yi)器。電(dian)(dian)(dian)泳(yong)是一種帶電(dian)(dian)(dian)分(fen)(fen)子(zi)在電(dian)(dian)(dian)場(chang)中向著電(dian)(dian)(dian)性相(xiang)反(fan)的電(dian)(dian)(dian)極移動的現(xian)(xian)象(xiang)(xiang)。利用電(dian)(dian)(dian)泳(yong)現(xian)(xian)象(xiang)(xiang)進行物質分(fen)(fen)離的技術,稱電(dian)(dian)(dian)泳(yong)技術。
自從(cong)1946年(nian)(nian)瑞典物理化(hua)學家(jia)Tiselius教(jiao)授研(yan)制的(de)(de)第一臺商品(pin)化(hua)移界電(dian)泳系統問世(shi)以(yi)來(lai),電(dian)泳分析(xi)(xi)儀發展極(ji)其迅速。特別是隨著支持介質的(de)(de)更新,各(ge)種(zhong)(zhong)各(ge)樣的(de)(de)電(dian)泳分析(xi)(xi)裝置相(xiang)(xiang)繼推出,以(yi)適應不同(tong)國家(jia)實驗室(shi)進行教(jiao)學、臨床和科研(yan)工作的(de)(de)需要。20世(shi)紀70年(nian)(nian)代以(yi)來(lai),已有越(yue)來(lai)越(yue)多的(de)(de)自動(dong)化(hua)電(dian)泳分析(xi)(xi)儀相(xiang)(xiang)繼被引入臨床實驗室(shi),并在各(ge)種(zhong)(zhong)疾病的(de)(de)臨床診治中發揮著越(yue)來(lai)越(yue)重要的(de)(de)作。
1.早期階(jie)段(duan)(~1970年以前(qian))
支持介(jie)質有醋(cu)酸纖維素薄膜(簡(jian)稱醋(cu)纖膜)及瓊脂(zhi)糖凝膠兩(liang)大類,這(zhe)一時期(qi)的電(dian)泳(yong)分析(xi)儀多用(yong)于蛋白質如血(xue)清蛋白、脂(zhi)蛋白、血(xue)紅蛋白等項目(mu)分析(xi)。
2.中(zhong)期階段(1970年~1990年)
這一時期電泳分析儀主要是可見光/熒光雙系統自動(dong)電泳掃(sao)描儀,熒光試劑(ji)與熒光掃(sao)描儀的(de)推出,在(zai)臨床上(shang)極大地方便了乳(ru)酸脫(tuo)氫酶(LD)和肌(ji)酸激酶(CK)同(tong)工酶的(de)測定。
3.發展階段(duan)(1990年~至今)
這一時期電(dian)泳分析儀(yi)以自(zi)動(dong)化為最大變化特點。常見有全(quan)自(zi)動(dong)熒光/可見光雙系統電(dian)泳儀(yi)、全(quan)自(zi)動(dong)醋纖膜(mo)電(dian)泳儀(yi)、全(quan)自(zi)動(dong)瓊(qiong)脂糖電(dian)泳儀(yi)等幾類。
在溶液中能吸(xi)(xi)附(fu)帶(dai)電(dian)質(zhi)點或本身帶(dai)有(you)(you)可解離基團的(de)(de)物(wu)(wu)質(zhi)顆粒(li),如(ru)蛋(dan)白質(zhi)、氨基酸等,在一(yi)定(ding)的(de)(de)pH值條(tiao)件下,于直(zhi)流電(dian)場中必(bi)然會(hui)受到(dao)電(dian)性相反(fan)的(de)(de)電(dian)極吸(xi)(xi)引(yin)而發生移動。不(bu)同物(wu)(wu)質(zhi)的(de)(de)顆粒(li)在電(dian)場中的(de)(de)移動速度除與(yu)其(qi)帶(dai)電(dian)狀態(tai)和(he)電(dian)場強度有(you)(you)關(guan)外,還與(yu)顆粒(li)的(de)(de)大(da)小、形狀和(he)介質(zhi)黏度有(you)(you)關(guan)。根據這(zhe)一(yi)特征,應用(yong)電(dian)泳法便可以對不(bu)同物(wu)(wu)質(zhi)進行(xing)定(ding)性或定(ding)量(liang)分析,或將一(yi)定(ding)混合物(wu)(wu)進行(xing)組(zu)分分析或單個組(zu)分提取制備,電(dian)泳儀正是基于上述(shu)原理設(she)計(ji)制造的(de)(de)。
電泳(yong)的影響因(yin)素很多(duo),主要有被分離物質的帶電荷量多(duo)少、電場強(qiang)度、緩沖液的pH值和離子(zi)強(qiang)度及(ji)支持介(jie)質的化學惰性。
常用電泳(yong)設備的基(ji)本結構包括:電源、電泳(yong)槽及附加裝置(zhi)。
根據電(dian)泳(yong)中(zhong)是否(fou)使用支持介質(zhi)分(fen)為自由(you)電(dian)泳(yong)和區帶(dai)電(dian)泳(yong)。
自(zi)由(you)電(dian)(dian)(dian)泳(yong)不使(shi)用(yong)(yong)支持介質(zhi)(zhi),電(dian)(dian)(dian)泳(yong)在(zai)(zai)溶(rong)液(ye)中(zhong)(zhong)進(jin)行。這(zhe)類電(dian)(dian)(dian)泳(yong)又分為非自(zi)由(you)界(jie)面(mian)(mian)電(dian)(dian)(dian)泳(yong)和自(zi)由(you)界(jie)面(mian)(mian)電(dian)(dian)(dian)泳(yong)兩類。非自(zi)由(you)界(jie)面(mian)(mian)電(dian)(dian)(dian)泳(yong)指懸浮在(zai)(zai)溶(rong)液(ye)中(zhong)(zhong)的帶電(dian)(dian)(dian)粒子(如各種(zhong)細胞)通(tong)電(dian)(dian)(dian)后全(quan)部(bu)移動,不出現(xian)界(jie)面(mian)(mian),如顯微電(dian)(dian)(dian)泳(yong)等。自(zi)由(you)界(jie)面(mian)(mian)電(dian)(dian)(dian)泳(yong)中(zhong)(zhong)被分離物質(zhi)(zhi)集中(zhong)(zhong)在(zai)(zai)某(mou)一層,形成(cheng)各自(zi)的界(jie)面(mian)(mian)而進(jin)行定性或定量分析。自(zi)由(you)界(jie)面(mian)(mian)電(dian)(dian)(dian)泳(yong)需要昂貴精(jing)密的電(dian)(dian)(dian)流儀(yi)器,僅在(zai)(zai)少數(shu)特殊電(dian)(dian)(dian)泳(yong)如等電(dian)(dian)(dian)聚焦(jiao)電(dian)(dian)(dian)泳(yong)和等速電(dian)(dian)(dian)泳(yong)中(zhong)(zhong)使(shi)用(yong)(yong)。
區帶電(dian)(dian)泳(yong)(yong)(yong)(yong)(yong)都使用支持(chi)介(jie)(jie)質,根據支持(chi)介(jie)(jie)質不同分(fen)為濾紙電(dian)(dian)泳(yong)(yong)(yong)(yong)(yong)、醋纖膜(mo)電(dian)(dian)泳(yong)(yong)(yong)(yong)(yong)、薄層(ceng)電(dian)(dian)泳(yong)(yong)(yong)(yong)(yong)和凝膠(jiao)電(dian)(dian)泳(yong)(yong)(yong)(yong)(yong)等。此外(wai),根據支持(chi)介(jie)(jie)質的裝(zhuang)置形(xing)式不同又可分(fen)為水平板(ban)(ban)式電(dian)(dian)泳(yong)(yong)(yong)(yong)(yong)、垂直(zhi)板(ban)(ban)式電(dian)(dian)泳(yong)(yong)(yong)(yong)(yong)、垂直(zhi)盤狀電(dian)(dian)泳(yong)(yong)(yong)(yong)(yong)、毛細(xi)管電(dian)(dian)脈、橋形(xing)電(dian)(dian)泳(yong)(yong)(yong)(yong)(yong)和連續流(liu)動電(dian)(dian)泳(yong)(yong)(yong)(yong)(yong)等。
常見的幾種電泳(yong)儀有:
1.全自(zi)動熒光/可(ke)見(jian)光雙(shuang)系統電泳儀
具有熒(ying)光(guang)/可見光(guang)雙系統,使用熒(ying)光(guang)試劑項目(mu)如CK、LD同工(gong)酶。優點靈敏度、準確度高且(qie)采用高壓、低溫系統,速(su)度非常快。
2.全自動醋纖膜(mo)電泳(yong)儀(yi)
為可見光單(dan)系(xi)統(tong),使用醋纖膜電泳片,優點為自動化程度更(geng)高。多用于(yu)臨(lin)床常規血(xue)清蛋白電泳分析。
3.全自動瓊脂糖電泳儀
為(wei)可(ke)見(jian)光單系統,使(shi)用(yong)瓊脂糖凝(ning)膠電泳膠片,優點為(wei)靈(ling)敏度高(gao),可(ke)用(yong)于(yu)低濃度蛋白(bai)檢驗,如(ru)尿(niao)蛋白(bai)及腦脊液蛋白(bai),同工酶的分離效果也相當不錯,所能做(zuo)項(xiang)目較多且(qie)靈(ling)敏度較高(gao)。
4.全自動電泳(yong)分析系(xi)統(tong)
該電泳(yong)(yong)儀(yi)集(ji)中了上述(shu)儀(yi)器的(de)優點,自動點樣、電泳(yong)(yong)、呈色(se)(se)(或染色(se)(se)、脫色(se)(se))、烘(hong)干。可用(yong)(yong)各種電泳(yong)(yong)片,包(bao)括瓊脂片、醋酸片、聚(ju)丙烯(xi)酰(xian)胺等(deng),采用(yong)(yong)可見(jian)光及熒光呈色(se)(se)雙系統(tong),是一種較理想的(de)電泳(yong)(yong)儀(yi)。
對不同(tong)物(wu)質進(jin)行(xing)定性或定量分(fen)析,或將一(yi)定混合(he)物(wu)進(jin)行(xing)組分(fen)分(fen)析或單個組分(fen)提取制備,應用(yong)于(yu)臨床醫學(xue)的實驗(yan)(yan)室檢(jian)驗(yan)(yan)或科研(yan)實驗(yan)(yan)研(yan)究。
1.首先用導線將電(dian)(dian)泳槽的兩(liang)個電(dian)(dian)極(ji)與電(dian)(dian)泳儀的直流(liu)輸出(chu)端聯接,注(zhu)意極(ji)性(xing)不要接反。
2.電(dian)(dian)泳(yong)儀電(dian)(dian)源開關(guan)調至關(guan)的(de)位置,電(dian)(dian)壓(ya)(ya)旋鈕轉(zhuan)到(dao)最小,根(gen)據工作需(xu)要選擇穩(wen)壓(ya)(ya)穩(wen)流方式及電(dian)(dian)壓(ya)(ya)電(dian)(dian)流范圍。
3.接通電(dian)(dian)源,緩(huan)緩(huan)旋轉電(dian)(dian)壓調節鈕直(zhi)到達到的所需電(dian)(dian)壓為止(zhi),設定電(dian)(dian)泳終止(zhi)時間,此時電(dian)(dian)泳即開始進行(xing)。
4.工(gong)作完畢(bi)后,應將各旋(xuan)鈕、開關旋(xuan)至零位(wei)或關閉狀態,并撥(bo)出電泳插(cha)頭(tou)。
1.電(dian)泳(yong)儀(yi)通電(dian)進入(ru)工作(zuo)狀態后,禁止(zhi)人體接(jie)觸電(dian)極、電(dian)泳(yong)物及其它可能(neng)帶電(dian)部分,也不能(neng)到電(dian)泳(yong)槽內取(qu)放東西,如需(xu)要應先(xian)斷電(dian),以(yi)(yi)免觸電(dian)。同時要求儀(yi)器必須(xu)有良好接(jie)地端,以(yi)(yi)防漏電(dian)。
2.儀器通電后,不要(yao)臨時增(zeng)加或撥除(chu)輸出導(dao)線插頭,以防短路(lu)現(xian)象(xiang)發生(sheng),雖然儀器內部(bu)附(fu)設有(you)保險(xian)絲,但短路(lu)現(xian)象(xiang)仍有(you)可能(neng)導(dao)致儀器損(sun)壞。
3.由(you)于不(bu)(bu)同(tong)(tong)(tong)(tong)介質支(zhi)持物(wu)(wu)的(de)(de)電阻(zu)值不(bu)(bu)同(tong)(tong)(tong)(tong),電泳(yong)時所通(tong)過的(de)(de)電流量也(ye)不(bu)(bu)同(tong)(tong)(tong)(tong),其泳(yong)動速度及泳(yong)至終點所需(xu)時間也(ye)不(bu)(bu)同(tong)(tong)(tong)(tong),故不(bu)(bu)同(tong)(tong)(tong)(tong)介質支(zhi)持物(wu)(wu)的(de)(de)電泳(yong)不(bu)(bu)要同(tong)(tong)(tong)(tong)時在同(tong)(tong)(tong)(tong)一(yi)電泳(yong)儀(yi)上進行(xing)。
4.在總電(dian)流不超過儀器額定電(dian)流時(shi)(最(zui)大電(dian)流范圍),可以多槽關聯使用,但要(yao)注意不能超載(zai),否則容易影響儀器壽命。
5.某(mou)些特殊情(qing)況下需檢查儀器電泳輸入情(qing)況時,允(yun)許在(zai)穩(wen)壓(ya)狀態下空(kong)載開(kai)(kai)機(ji),但在(zai)穩(wen)流狀態下必須先接好(hao)負(fu)載再開(kai)(kai)機(ji),否則電壓(ya)表指針將(jiang)大幅度跳動,容易(yi)造成不必要的人為機(ji)器損壞(huai)。
6.使(shi)用(yong)過程中發現(xian)異(yi)(yi)常現(xian)象(xiang),如較大(da)噪音、放電(dian)或(huo)異(yi)(yi)常氣味,須立即(ji)切斷電(dian)源,進行檢修,以免發生(sheng)意(yi)外事故。
1.電泳儀的(de)輸出達不到設定值
電泳儀的輸出值(zhi)狀態(tai)遵循“歐姆定律”:電壓U=電流I×(電泳槽)電阻R
電阻R相對不變的情況(kuang)下,U、I、P(功率P=電流I×電壓U)中任(ren)意(yi)1個參數(shu)恒定,其(qi)他(ta)參數(shu)也隨之恒定;而任(ren)意(yi)1個參數(shu)變化,其(qi)他(ta)參數(shu)也隨之正比變化。
如(ru)果(guo)(guo)電(dian)泳(yong)儀(yi)(yi)的輸(shu)出電(dian)壓(ya)U達不到預置值,應首先(xian)觀察I或P是否已經恒定,或者已經達到電(dian)泳(yong)儀(yi)(yi)所規定的最大(da)I或P(JY電(dian)泳(yong)儀(yi)(yi)均有明確指示(shi)燈標(biao)志)。如(ru)果(guo)(guo)尚未達到極限值,將(jiang)已經恒定I或P的設置調(diao)大(da)(有必要(yao)的話至極限值),才能夠(gou)提高電(dian)壓(ya)輸(shu)出。
如(ru)(ru)果電泳儀的電流(liu)I達不到預置(zhi)值,可調整電壓U或(huo)功率P。如(ru)(ru)果電泳儀的功率P達不到預置(zhi)值,可調整電壓U或(huo)電流(liu)I。
2.電腦控制電泳儀過壓(ya)報(bao)警(jing)
(1)檢查是否(fou)空載使用。
(2)是否電泳槽未(wei)加(jia)緩沖液。
(3)是否電泳槽鉑(bo)金(jin)絲(si)斷(duan)。
3.過流保護
(1)是否(fou)存(cun)在電泳槽短路(lu)現象。
(2)緩沖液是否(fou)選錯。
4.漏電保護
(1)是否有液體(ti)濺入(ru)儀器內部或輸出接口上。
(2)是否有(you)很(hen)多灰(hui)塵(chen)落(luo)入儀(yi)器(qi)內部。