李冰石,姜婷婷
深圳大學(xué)化學(xué)與化工學(xué)院,深圳518060
1954年,F(xiàn)orster等[1]發(fā)現(xiàn)芘的熒光強(qiáng)度隨其溶液濃度的增加而減弱,這種濃度增加所引起的猝滅主要是由于處于基態(tài)和激發(fā)態(tài)的芳香族分子間相互碰撞形成了三明治狀激子,這一現(xiàn)象被稱為“濃度猝滅效應(yīng)”[2].同時(shí),有機(jī)發(fā)光材料在制成固態(tài)薄膜時(shí),也會(huì)因?yàn)橄噜彿肿娱g的π-π堆積發(fā)生熒光猝滅,即聚集導(dǎo)致熒光猝滅(aggregation-caused quenching,ACQ).為了避免聚集熒光猝滅現(xiàn)象發(fā)生,熒光探針只能在極稀的溶液中使用[3-4],嚴(yán)格控制其濃度或與待測(cè)物結(jié)合的分子數(shù),而濃度降低也使檢測(cè)靈敏度隨之降低[5-9].
2001年,唐本忠等[10]發(fā)現(xiàn)一種硅雜環(huán)戊二烯(Silole)的衍生物六苯基噻咯(hexaphenylsilole,HPS,圖1中的分子1)具有與ACQ相反的特性,該類分子在溶液狀態(tài)下幾乎不發(fā)光,而聚集以后發(fā)光顯著增強(qiáng).這類現(xiàn)象被命名為聚集誘導(dǎo)發(fā)光(aggregation-induced emission,AIE).AIE現(xiàn)象的發(fā)現(xiàn)為解決ACQ問題提供了新途徑,引起了國(guó)內(nèi)外研究者的廣泛興趣[11].AIE分子的類型從噻咯類(圖1)拓展到環(huán)狀多烯型、多芳香取代乙烯型、腈取代二苯乙烯型和吡喃型等[12-13].這些分子都具有共軛結(jié)構(gòu)及可圍繞單鍵旋轉(zhuǎn)的苯環(huán).其中,四苯基乙烯(teraphenylethylene,TPE)類衍生物(如圖2)因其合成簡(jiǎn)單,易于功能化,相關(guān)應(yīng)用研究已取得顯著進(jìn)展.
圖1 Silole衍生物的結(jié)構(gòu)式Fig.1 Chemical structures of Silole derivatives
關(guān)于AIE現(xiàn)象的產(chǎn)生,存在多種解釋:分子內(nèi)共平面、光化學(xué)或光物理過程的抑制、非緊密堆積、形成J-聚集體(J-aggregate formation)以及形成特殊激級(jí)締合物(excimer)等[14-15].其中最具影響的是“分子內(nèi)旋受限”假說[16-17],該假說認(rèn)為AIE分子的聚集導(dǎo)致分子內(nèi)旋轉(zhuǎn)受限,抑制了非輻射能量的轉(zhuǎn)移,導(dǎo)致體系熒光增強(qiáng).
分子內(nèi)旋受限假說得到大量實(shí)驗(yàn)數(shù)據(jù)支持.以HPS的四氫呋喃溶液為例,降低溶液溫度、增大體系黏度或壓力,都可以使溶液的熒光增強(qiáng)[18-21].溫度降低使整個(gè)溶液凍結(jié)成“玻璃態(tài)”,而黏度或壓力增大則減小了相鄰分子間的距離,3種因素改變都導(dǎo)致了分子內(nèi)旋轉(zhuǎn)受限,阻斷非輻射能量的轉(zhuǎn)移,使溶液的熒光增強(qiáng).
分子內(nèi)旋轉(zhuǎn)受限對(duì)其熒光強(qiáng)度的影響還可以通過向分子結(jié)構(gòu)中引入限制分子內(nèi)旋轉(zhuǎn)的基團(tuán)進(jìn)行驗(yàn)證[22].例如,向HPS的苯環(huán)取代基上引入異丙基,當(dāng)異丙基位于間位和對(duì)位上(圖1中的分子44.1和44.2),2個(gè)苯環(huán)可以自由轉(zhuǎn)動(dòng),而當(dāng)異丙基位于相鄰的2個(gè)苯環(huán)上(圖1中的分子44.3),則限制了2個(gè)苯環(huán)的自由旋轉(zhuǎn).相對(duì)應(yīng)的3種分子的熒光光譜,分子 44.3的發(fā)光要遠(yuǎn)遠(yuǎn)強(qiáng)于分子 44.1和44.2的,驗(yàn)證了苯環(huán)的自由旋轉(zhuǎn)被限制后,分子的非輻射能量轉(zhuǎn)移被阻斷,分子熒光增強(qiáng).
圖2 幾種TPE化合物的化學(xué)結(jié)構(gòu)Fig.2 Chemical structures of TPE derivatives
近年來,眾多研究者已對(duì)AIE的研究進(jìn)展進(jìn)行了評(píng)述[11,23-28],但主要集中在分子的設(shè)計(jì)合成,而AIE分子在生物/化學(xué)傳感器上的應(yīng)用研究進(jìn)展則介紹較少.針對(duì)這一不足,本綜述主要介紹AIE分子在化學(xué)/生物傳感器方面的應(yīng)用研究進(jìn)展.AIE在生物/化學(xué)傳感器方面的應(yīng)用,主要通過對(duì)AIE分子進(jìn)行化學(xué)修飾,使AIE分子可以與被測(cè)物通過靜電作用、疏水作用及形成配位鍵方式相結(jié)合,誘導(dǎo)分子熒光增強(qiáng),形成“光開關(guān)”效應(yīng),實(shí)現(xiàn)對(duì)待測(cè)物的檢測(cè).本文主要介紹基于AIE分子熒光特性用于生物分子(包括蛋白質(zhì)、胰島素及DNA)等檢測(cè)的生物傳感器和用于金屬離子及有害化學(xué)物質(zhì)檢測(cè)的化學(xué)傳感器.
目前,AIE分子在生物分子檢測(cè)方面的檢測(cè)機(jī)理主要是基于AIE分子上的帶電基團(tuán),如羧基、磺酸基、季銨基等與待測(cè)生物分子通過靜電作用或利用疏水作用,誘導(dǎo)AIE分子聚集,使熒光增強(qiáng),產(chǎn)生“光開關(guān)”效應(yīng).其中,以TPE的水溶性衍生物的研究最為深入,主要應(yīng)用研究集中在對(duì)蛋白、DNA及某些酶抑制劑的檢測(cè).
DNA的鏈段長(zhǎng)度對(duì)誘導(dǎo)AIE分子聚集具有重要影響,當(dāng)長(zhǎng)鏈DNA在DNA酶作用下發(fā)生斷裂,與DNA作用的AIE分子聚集態(tài)被破壞,熒光信號(hào)隨之衰減.基于DNA鏈段長(zhǎng)度與熒光強(qiáng)度的關(guān)系,利用帶正電的AIE分子2(圖1)可以對(duì)DNA酶和DNA 斷裂進(jìn)行檢測(cè)[29].
肝磷脂是表面帶有負(fù)電荷的生物大分子,臨床上用于治療各種彌散性血管內(nèi)凝血.利用分子2與肝磷脂的靜電作用,可以對(duì)肝磷脂與蛋白質(zhì)相互作用進(jìn)行監(jiān)測(cè)[30].分子2的緩沖溶液發(fā)光很弱,加入肝磷脂后,溶液發(fā)光顯著增強(qiáng),加入能與肝磷脂特異性結(jié)合的精蛋白,溶液的熒光信號(hào)則明顯減弱.分子2所攜帶的季銨基陽離子與肝磷脂上的磺酸根離子和羧酸根離子發(fā)生靜電作用,使分子2在肝磷脂表面而發(fā)生了聚集,導(dǎo)致溶液熒光顯著增強(qiáng).當(dāng)化合物2被與肝磷脂具有更強(qiáng)特異性作用的精蛋白取代后,其聚集態(tài)也被破壞,熒光相應(yīng)變?nèi)?
分子2還可以用于三磷酸腺苷(Adenosine triphosphate,ATP)的檢測(cè)及其水解過程的監(jiān)控.其熒光強(qiáng)度隨著ATP的加入逐漸增強(qiáng),而ATP酶的加入則使溶液熒光減弱,利用這一性質(zhì)可以實(shí)現(xiàn)對(duì)ATP水解的連續(xù)監(jiān)測(cè)和其水解抑制物的檢測(cè)[31].
含有雙取代季銨基的水溶性TPE衍生物分子5(如圖2),在水溶液中發(fā)光很弱,而加入小牛胸腺DNA(ctDNA)或牛血清蛋白(bovine serum albumin,BSA)后,生物分子誘導(dǎo)TPE聚集,溶液熒光強(qiáng)度大大增強(qiáng)[32].利用這一“光開關(guān)”效應(yīng),可實(shí)現(xiàn)對(duì)這兩類生物分子的檢測(cè).
2007年Tong等[33]報(bào)道了磺酸基取代的TPE分子6(圖2)與BSA結(jié)合后,其溶液的熒光上百倍地增強(qiáng).其熒光增強(qiáng)機(jī)理為TPE分子插入到BSA的疏水結(jié)構(gòu)中,有效抑制了苯環(huán)的旋轉(zhuǎn)及非輻射能量轉(zhuǎn)移,從而使熒光增強(qiáng).
利用分子6(圖2)與生物分子的靜電作用,Wang等[34]發(fā)展了一種連續(xù)、便捷的檢測(cè)乙酰膽堿濃度及乙酰膽堿酯酶抑制劑的方法.乙酰膽堿是一種中樞神經(jīng)遞質(zhì),乙酰膽堿酯酶(acetylcholinesterase,AchE)是神經(jīng)傳導(dǎo)中的關(guān)鍵酶之一,主要存在神經(jīng)組織、血液、肝臟和肌肉中,乙酰膽堿被AchE水解是調(diào)控中樞反應(yīng)系統(tǒng)的關(guān)鍵環(huán)節(jié).大腦中的乙酰膽堿含量過低與阿爾茨海默病(Aelzheimer disease,AD)直接相關(guān)[35].該方法的檢測(cè)原理是基于分子6與乙酰膽堿的靜電作用,使分子發(fā)生聚集,分子6的熒光強(qiáng)度增強(qiáng)上百倍,而當(dāng)乙酰膽堿被乙酰膽堿酯酶水解后,其水解產(chǎn)物則與分子6帶同種電荷,難以誘導(dǎo)其聚集,導(dǎo)致分子6熒光強(qiáng)度下降.利用這一“開關(guān)”效應(yīng),可以對(duì)乙酰膽堿酯酶抑制劑進(jìn)行篩選.在這一工作基礎(chǔ)上,Peng等[36]利用邁克爾反應(yīng),將長(zhǎng)的烷基引入硫代膽堿,發(fā)展了新的選擇性檢測(cè)AchE活性及篩選其抑制劑的熒光方法,該檢測(cè)方法具有快速、簡(jiǎn)單和易操作等優(yōu)點(diǎn).
人血清蛋白是血漿中主要的蛋白質(zhì)成分,實(shí)現(xiàn)它的可視化檢測(cè)具有重要的生物學(xué)意義.2010年,Hong等[37]報(bào)道了利用分子6對(duì)人體血清蛋白(human serumalbumin,HAS)的結(jié)構(gòu)轉(zhuǎn)換進(jìn)行可視化檢測(cè)的方法.HSA與分子6結(jié)合后會(huì)誘導(dǎo)其AIE特性,在凝膠電泳實(shí)驗(yàn)中分子6可以作為一種快速靈敏的蛋白質(zhì)著色劑,實(shí)現(xiàn)對(duì)HSA結(jié)構(gòu)變化的可視化檢測(cè),該方法具有操作簡(jiǎn)便、檢測(cè)限低和靈敏度高等特點(diǎn).
胰島素(Trypsin)是胰腺分泌的最重要的消化酶,胰島素濃度的增加會(huì)導(dǎo)致一些胰腺疾病的產(chǎn)生.Xue等[38]利用單取代磺酸基的TPE衍生物分子7(圖2),建立了一種快速檢測(cè)胰島素的熒光方法.通過胰島素上帶正電的精氨酸與分子7上的磺酸基發(fā)生靜電作用及疏水作用誘導(dǎo)分子聚集,使分子7的熒光強(qiáng)度逐漸增大.精氨酸水解后,分子7的聚集態(tài)被破壞,溶液熒光減弱.依此可以建立一種無標(biāo)記的連續(xù)檢測(cè)胰島素含量的熒光方法,檢測(cè)限可以達(dá)到0.2 μg/mL.同時(shí),還可以實(shí)現(xiàn)對(duì)胰島素抑制劑的篩選.
基于分子AIE特性進(jìn)行的離子檢測(cè),主要原理是利用金屬離子誘導(dǎo)DNA形成有利于AIE分子插入的穩(wěn)定高級(jí)結(jié)構(gòu),或利用AIE分子取代基與金屬離子的配位作用,誘導(dǎo)AIE分子聚集,使其熒光增強(qiáng),形成“光開關(guān)”效應(yīng).
鉀離子是單鏈DNA自組裝成G四倍體的關(guān)鍵性離子,AIE分子8(圖2)可以插入到G四倍體中,使原本幾乎無熒光的溶液熒光顯著增強(qiáng),形成“光開關(guān)”效應(yīng)[39],而其他陽離子(Na+、Li+、NH4+、Mg2+和Ca2+)則不能誘導(dǎo)G四倍體的形成,據(jù)此可以實(shí)現(xiàn)對(duì)鉀離子的檢測(cè).
在TPE分子上引入可以與Zn2+進(jìn)行配位的羧基[40](圖2分子9)或單三聯(lián)吡啶、雙三聯(lián)吡啶[41](圖2分子10和11),通過Zn2+與羧基、三聯(lián)吡啶的配位作用誘導(dǎo)分子的AIE特性,實(shí)現(xiàn)對(duì)Zn2+檢測(cè)的“光開關(guān)”效應(yīng).同時(shí),分子10與Zn2+形成的配合物還可以實(shí)現(xiàn)對(duì)Fe3+、Fe2+的鑒別[41].Fe2+可以誘導(dǎo)分子10與Zn2+形成的配合物發(fā)生電荷轉(zhuǎn)移,使溶液的熒光猝滅,同時(shí)溶液顏色由黃白色變?yōu)榈凵?,而Fe3+則對(duì)配合物熒光影響較小,溶液顏色幾乎不變,進(jìn)而實(shí)現(xiàn)對(duì)Fe2+的直觀鑒別.
利用金屬離子與AIE分子的配位作用,誘導(dǎo)分子聚集,使分子產(chǎn)生AIE特性,據(jù)此也可以實(shí)現(xiàn)對(duì)金屬離子的檢測(cè).Liu等[42]將TPE分子分別修飾上腺嘌呤和胸腺嘧啶(圖3分子12和13),與Ag+和Hg2+進(jìn)行配位,利用配位作用誘導(dǎo)分子聚集,形成“光開關(guān)”效應(yīng),實(shí)現(xiàn)對(duì)2種離子的檢測(cè).其熒光強(qiáng)度的增加在一定范圍內(nèi)與待測(cè)離子濃度呈線性關(guān)系,且具有很好的專一性,其中,Ag+和Hg2+的檢測(cè)限分別可以達(dá)到0.34 μmol/L 和0.37 μmol/L.
圖3 分子12和13的結(jié)構(gòu)式Fig.3 Chemical structures of compound 12 and 13
氰化物對(duì)人類健康和生存環(huán)境具有極大危害,目前用于氰化物檢測(cè)的化學(xué)傳感器多是利用其強(qiáng)的配位能力和親核力,但是這些方法存在明顯弊端,如選擇性差、非水溶性介質(zhì)等.2009年,Peng等[43]報(bào)道了一種利用分子AIE特性檢測(cè)氰化物的方法,該檢測(cè)方法依據(jù)氰化物與帶有三氟乙酰氨基的化合物親核加成,生成一種兩性化合物誘導(dǎo)化合物2(圖1)聚集,使溶液的發(fā)光增強(qiáng).其中氰化物的檢測(cè)限可達(dá)7.74 μmol/L,比火災(zāi)受害者血液中氰化物的濃度還低.且化合物2對(duì)常見的陰離子AcO-、Br-、Cl-、F-、H2PO4-、HSO4-、N3-和NO3-的響應(yīng)都很弱,具有良好的選擇性.
Cr6+對(duì)人體健康有很大危害,CrO42-能進(jìn)入到細(xì)胞內(nèi)氧化DNA,對(duì)人體造成損害.Toal等[44]合成了分子3(圖1),利用不良溶劑誘導(dǎo)分子形成納米顆粒,使其熒光增強(qiáng),而CrO42-對(duì)熒光具有猝滅效應(yīng),其猝滅效率比常見陰離子高出數(shù)倍,且這種檢測(cè)對(duì)淡水及海水中鉻酸根的檢測(cè)均很有效.
爆炸物檢測(cè)是AIE化合物應(yīng)用研究的重要方面.三硝基甲苯(trinitrotoluene,TNT)、二硝基甲苯(dinitrotoluene,DNT)及2,4,6-三硝基苯酚(picric acid,PA)等危險(xiǎn)品的檢測(cè)對(duì)社會(huì)安全及環(huán)境保護(hù)方面意義重大.研究發(fā)現(xiàn)PA和TNT等爆炸物對(duì)具有AIE特性的超支化聚合物及介孔材料可產(chǎn)生猝滅效應(yīng)[45-54],PA導(dǎo)致聚合物激發(fā)態(tài)的能量轉(zhuǎn)移,使分子熒光猝滅,而TNT則通過電荷轉(zhuǎn)移導(dǎo)致AIE分子熒光的猝滅,基于這一熒光猝滅效應(yīng)可以制備對(duì)爆炸物檢測(cè)的化學(xué)傳感器.
AIE現(xiàn)象發(fā)現(xiàn)至今,雖然只有短短十幾年,但其發(fā)展迅猛,影響深遠(yuǎn).它改變了人們長(zhǎng)期以來形成的習(xí)慣性認(rèn)識(shí)“分子聚集必然導(dǎo)致熒光淬滅”,讓研究者更全面地去探索分子聚集與其光學(xué)性質(zhì)的關(guān)系,這無疑為光電材料的設(shè)計(jì)和應(yīng)用提供了新的思路.AIE機(jī)理研究和應(yīng)用探索方面都取得了重要進(jìn)展,分子的內(nèi)旋轉(zhuǎn)受限假說的提出為解釋AIE現(xiàn)象提供了強(qiáng)有力的理論基礎(chǔ).
但用于生物分子體系中AIE分子的發(fā)光和檢測(cè)機(jī)理,還存在明顯不足,尚需進(jìn)一步豐富和完善,尤其是生物分子與AIE分子的相互作用,生物分子對(duì)AIE分子聚集的誘導(dǎo)尚未有一個(gè)公認(rèn)的解釋.疏水作用和靜電作用被認(rèn)為是兩者之間的主要作用方式,但這2種方式對(duì)分子聚集發(fā)光的影響是如何產(chǎn)生的,是以靜電作用為主,還是兩者協(xié)同作用,尚需進(jìn)一步的實(shí)驗(yàn)驗(yàn)證.聚集態(tài)的形成或解聚是聚集誘導(dǎo)發(fā)光機(jī)理的核心環(huán)節(jié)之一,但生物分子對(duì)AIE分子的聚集態(tài)的誘導(dǎo)的相關(guān)工作還未展開,主要原因是AIE領(lǐng)域目前的研究重點(diǎn)在于分子的設(shè)計(jì)合成,而納米科學(xué)技術(shù)在AIE相關(guān)研究中的應(yīng)用仍方興未艾.本課題組在近兩年開展了AIE分子聚集態(tài)的研究工作,發(fā)現(xiàn)分子聚集態(tài)結(jié)構(gòu)對(duì)其光學(xué)性質(zhì)具有重要影響,分子光學(xué)性質(zhì)的微小變化往往伴隨著分子聚集態(tài)的顯著改變.分子聚集態(tài)的表征對(duì)分子結(jié)構(gòu)設(shè)計(jì)及揭示聚集誘導(dǎo)發(fā)光機(jī)理都具有重要意義,這是今后AIE研究中值得深入研究的領(lǐng)域.AIE分子在生物/化學(xué)傳感器的應(yīng)用研究雖然在不斷被拓寬,如何實(shí)現(xiàn)從實(shí)驗(yàn)室到臨床及工業(yè)產(chǎn)業(yè)化應(yīng)用,也是一個(gè)需要研究者跨學(xué)科、共同協(xié)作來解決的問題.
/References:
[1]Forster T,Kasper K.Ein konzentrationsumschlag der fluoreszenz [J].Zeitschrift für Physikalische Chemie,1954,1(5/6):275-277.
[2]Birks J B.Photophysics of Aromatic Molecules[M].London:Wiley,1970.
[3]Slav1'k J.Fluorescence Microscopy and Fluorescent Probes[M].New York:Plenum,1996.
[4]Valeur B.Molecular Fluorescence:Principle and Applications[M].Weinheim(German):Wiley-VCH,2002.
[5]Sapsford K E,Berti L,Medintz I L.Materials for fluorescence resonance energy transfer analysis:beyond traditional donor-acceptor combinations[J].Angewandte Chemie International Edition,2006,45(28):4562-4589.
[6]Borisov S M,Wolfbeis O S.Optical biosensors[J].Chemical Society Reviews,2008,108(2):423-461.
[7]Domaille D W,Que E L,Chang C J.Synthetic fluorescent sensors for studying the cell biology of metals[J].Nature Chemical Biology,2008,4(3):168-175.
[8]Lim M H,Lippard S J.Metal-based turn-on fluorescent probes for sensing nitric oxide[J].Accounts of Chemical Research,2007,40(1):41-51.
[9]Giepmans B N G,Adams S R,Ellisman M H,et al.The fluorescent toolbox for assessing protein location and function [J].Science,2006,312(5771):217-224.
[10]Luo J,Xie Z,Lam J W Y,et al.Aggregation-induced emission of 1-methyl-1,2,3,4,5-pentaphenylsilole[J].Chemical Communication,2001(18):1740-1741.
[11]Yan Jiming,Qin Anjun,Sun Jingzhi,et al.Application of AIE-active molecules in biosensing[J].Chinese Sci Bull,2010,55(13):1206-1213.(in Chinese)閆繼明,秦安軍,孫景志,等.聚集誘導(dǎo)發(fā)光分子在生物傳感檢測(cè)領(lǐng)域的應(yīng)用 [J].科學(xué)通報(bào),2010,55(13):1206-1213.
[12]Tong H,Dong Y.Color-tunable,aggregation-induced emission of a butterfly-shaped molecule comprising a pyran skeleton and two cholesteryl wings[J].Journal of Physical Chemistry B,2007,111(8):2000-2007.
[13]Tong H,Dong Y,Hong Y N,et al.Aggregation-induced emission:effects of molecular structure,solid-state conformation,and morphological packing arrangement on lightemitting behaviors of diphenyldi-benzofulvene derivatives[J].Journal of Physical Chemistry C,2007,111(5):2287-2294.
[14]Hong Y N,Lam J W Y,Tang B Z.Aggregation-induced emission:phenomenon,mechanism and applications [J].Chemical Communication,2009(29):4332-4353.
[15]Hong Y N,Lam J W Y,Tang B Z.Aggregation-induced emission [J].Chemical Society Reviews,2011,40(11):5361-5388.
[16]Zhang Shuang,Qin Anjun,Sun Jingzhi,et al.Mechanism study of agreegation-induced emission [J].Progress in Chemistry,2011,23(4):623-636.(in Chinese)張 雙,秦安軍,孫景志,等.聚集誘導(dǎo)發(fā)光機(jī)理研究 [J].化學(xué)進(jìn)展,2011,23(4):623-636.
[17]Yu G,Yin S W,Liu Y Q,et al.Structures,electronic states,photoluminescence,and carrier transport properties of 1,1-disubstituted 2,3,4,5-tetraphenylsiloles [J].Journal of the American Chemical Society,2005,127(17):6335-6346.
[18]Chen J W,Law C C W,Lam J W Y,et al.Synthesis,light emission,nanoaggregation,and restricted intramolecular rotation of 1,1-substituted 2,3,4,5-tetraphenylsiloles[J].Chemical Materials,2003,15(7):1535-1546.
[19]Fan X,Sun J L,Wang F Z,et al.Photoluminescence and electroluminescence of hexaphenylsilole are enhanced by pressurization in the solid state[J].Chemical Communication,2008(26):2989-2991.
[20]Ren Y,Lam J W Y,Dong Y Q,et al.Enhanced emission efficiency and excited state lifetime due to restricted intramolecular motion in silole aggregates[J].Journal of Physical Chemistry B,2005,109(3):1135-1140.
[21]Ren Y,Lam J W Y,Dong Y Q,et al.Studies on the aggregation-induced emission of silole film and crystal by time-resolved fluorescence technique[J]. Chemical Physics Letters,2005,402(4):468-473.
[22]Li Z,Dong Y Q,Mi B X,et al.Structural control of the photoluminescence of silole regioisomers and their utility as sensitive regiodiscriminating chemosensors and efficient electroluminescent materials[J].Journal of Physical Chemistry B,2005,109(20):10061-10066.
[23]Wang M,Zhang G X,Zhang D Q,et al.Fluorescent bio/chemosensors based on silole and tetraphenylethene luminogens with aggregation-induced emission feature [J].Journal of Materials Chemistry,2010,20(10):1858-1867.
[24]Zhang Yunsheng,Qing Jiuhong,Xu Caihong.Research progress of application of silole derivatives with aggregation-induced emission [J].Silicone Material,2011,25(3):190-198.(in Chinese)張運(yùn)生,秦九紅,徐彩虹.聚集誘導(dǎo)發(fā)光的硅雜環(huán)戊二烯衍生物的應(yīng)用研究進(jìn)展 [J].有機(jī)硅材料,2011,25(3):190-198.
[25]Zhao Yuezhi,Cai Minmin,Qian Yan,et al.The systems with aggregation induced emission:compounds,emission,mechanisms and their applications[J].Progress in Chemistry,化學(xué)進(jìn)展,2013,25(203):296-321.(in Chinese)趙躍智,蔡敏敏,錢 妍,等.聚集誘導(dǎo)發(fā)光體系:化合物種類、發(fā)光機(jī)制及其應(yīng)用 [J].2013,25(203):296-321.
[26]Ma Qingyu,Guan Ruifang,Li Guozhong,et al.Progress in the synthesis and applications of silole compounds [J].Chinese Journal of Organic Chemistry,2011,31(9):1395-1405.(in Chinese)馬慶宇,關(guān)瑞芳,李國(guó)忠,等.硅雜環(huán)戊二烯的合成及應(yīng)用進(jìn)展 [J].有機(jī)化學(xué),2011,31(9):1395-1405.
[27]Xia Jing,Wu Yanmei,Zhang Yaling,et al.Recent progress of tetraphenylethenes with aggregation-induced emission [J].Imaging Science and Photochemisty,2012,30(1):9-25.(in Chinese)夏 晶,吳燕梅,張亞玲,等.具有聚集誘導(dǎo)發(fā)光特性的四苯基乙烯研究進(jìn)展 [J].影像科學(xué)與光化學(xué),2012,30(1):9-25.
[28]Zhao Guosheng,Shi Chuanxing,Guo Zhiqian,et al.Recent application progress on aggregation-induced emission[J].Chinese Journal of Organic Chemistry,2012,32(9):1620-1632.(in Chinese)趙國(guó)生,史川興,郭志前,等.聚集誘導(dǎo)發(fā)光應(yīng)用研究進(jìn)展 [J].有機(jī)化學(xué),2012,32(9):1620-1632.
[29]Wang M,Zhang D,Zhang G,et al.Fluorescence turn-on detection of DNA and label-free fluorescence nuclease assay based on the aggregation-induced emission of silole[J].Analytical Chemistry,2008,80(16):6443-6448.
[30]Wang M,Zhang D,Zhang G,et al.The convenient fluorescence turn-on detection of heparin with a silole derivative featuring an ammonium group [J].Chemical Communication,2008(37):4469-4471.
[31]Zhao M,Wang M,Liu H,et al.Continuous on-site labelfree ATP fluorometric assay based on aggregation-induced emission of silole [J].Langmuir,2009,25(2):676-678.
[32]Tong H,Hong Y N,Don Y Q,et al.Fluorescent“l(fā)ightup”bioprobes based on tetraphenylethylene derivatives with aggregation-induced emission characteristics [J].Chemical Communication,2006(35):3705-3707.
[33]Tong H,Hong Y,Dong Y,et al.Protein detection and quantitation by tetraphenylethene-based fluorescent probes with aggregation-induced emission characteristics [J].Journal of Physical Chemistry B,2007,111(40):11817-11823.
[34]Wang M,Gu X,Zhang G,et al.Convenient and continuous fluorometric assay method for acetylcholinesterase and inhibitor screening based on the aggregation-induced emission[J].Analytical Chemistry ,2009,81(11):4444-4449.
[35]Whitehouse P J,Price D L,Struble R G, et al.Alzheimer's disease and senile dementia:loss of neurons in the basal forebrain [J].Science,1982,215(4537):1237-1239.
[36]Peng L,Zhang G,Zhang D Q,et al.A fluorescence“turn-on”ensemble for acetylcholinesterase activity assay and inhibitor screening [J].Organic Letters,2009,11(17):4014-4017.
[37]Hong Y N,F(xiàn)eng C,Yu Y,et al.Quantitation,visualization,and monitoring of conformational transitions of human serum albumin by a tetraphenylethene derivative with ag-gregation-induced emission characteristics[J].Analytical Chemistry,2010,82(16):7035-7043.
[38]Xue W,Zhang G X,Zhang D Q,et al.A new fluorometric turn-on assay for trypsin and inhibitor screening with tetraphenylethenecompounds [J]. Organic Letters,2010,12(10):2274-2277.
[39]Hong Y N,Haussler M,Lam J W Y,et al.Labelfree fluorescent probing of G-quadruplex formation and real-time monitoring of DNA folding by a quaternized tetraphenylethene salt with aggregation-induced emission characteristics [J].Chemistry-A Europen Journal,2008,14(21):6428-6437.
[40]Sun F,Zhang G X,Zhang D X,et al.Aqueous fluorescence turn-on sensor for Zn2+with a tetraphenylethylene compound [J].Organic Letters,2011,13(24):6378-6381.
[41]Hong Y N,Chen S J,Liu J Z,et al.Fluorogenic Zn(II)and chromogenic Fe(II)sensors based on terpyridinesubstituted tetraphenylethenes with aggregation-induced emission characteristics[J].Applied Materials& Interfaces,2011,3(9):3411-3418.
[42]Liu L,Zhang G X,Xiang J F,et al.Fluorescence“turn on”chemosensors for Ag+and Hg2+based on tetraphenylethylene motif featuring adenine and thymine moieties[J].Organic Letters,2008,10(20):4581-4584.
[43]Peng L H,Wang M,Zhang G X,et al.A fluorescence turn-on detection of cyanide in aqueous solution based on the aggregation-induced emission [J].Organic Letters,2009,11(9):1943-1946.
[44]Toal S J,Jones K A,Magde D,et al.Luminescent silole nanoparticles as chemoselective sensors for Cr(VI)[J].Journal of the American Chemical Society,2005,127(33):11661-11665.
[45]Yuan W Z,Hu R R,Lam J W Y,et al.Conjugated hyperbranched poly(aryleneethynylene)s:synthesis,photophysical properties,superquenching by explosive,photopatternability,and tunable high refractive indices [J].Chemistry-A Europen Journal,2012,18(10):2847-2856.
[46]Hu R R,Lam J W Y,Liu J Z,et al.Hyperbranched conjugated poly(tetraphenylethene):synthesis,aggregation-induced emission,fluorescent photopatterning,optical limiting and explosive detection [J].Polymer Chemistry,2012,3(6):1481-1489.
[47]Li H K,Wang J,Sun J Z,et al.Metal-free click polymerization of propiolates and azides:facile synthesis of functional poly(aroxycarbonyltriazole)s[J].Polymer Chemistry,2012,3(4):1075-1083.
[48]Qin A J,Tang L,Lam J W Y,et al.Metal-free click polymerization:synthesis and photonic properties of poly(aroyltriazole)s [J].Advanced Functional Materials,2009,19(12):1891-1900.
[49]Li D D,Liu J Z,Liang Z Q,et al.Supersensitive detection of explosives by recyclable AIE luminogen-functionalized mesoporous materials[J].Chemical Communication,2012,48(57):7167-7169.
[50]Xu B W,Wu X F,Li H B,et al.Selective detection of TNT and picric acid by conjugated polymer film sensors with donor acceptor architecture [J].Macromolecules,2011,44(13):5089-5092.
[51]Liu J Z,Zhong Y C,Lam J W Y,et al.Hyperbranched conjugated polysiloles:synthesis,structure,aggregationenhanced emission,multicolor fluorescent photopatterning,and superamplified detection of explosives[J].Macromolecules,2010,43(11):4921-4936.
[52]Qin A J,Lam J W Y,Tang L,et al.Polytriazoles with aggregation-induced emission characteristics:synthesis by click polymerization and application as explosive chemosensors[J].Macromolecules,2009,42(5):1421-1424.
[53]Yuan W Z,Zhao H,Shen Y,et al.Luminogenic polyacetylenes and conjugate polyelectrolytes:synthesis,hybridization with carbon nanotubes,aggregation-induced emission,superamplification in emission quenching by explosives,and fluorescent assay for protein quantitation[J].Macromolecules,2009,42(24):9400-9411.
[54]Li H K,Mei J,Wang J,et al.Facile synthesis of poly(aroxycarbonyltriazole)s with aggregation-induced emission characteristics by metal-free click polymerization[J].Science China Chemistry,2011,54(4):611-616.