作為一(yi)個基本物理參量,溫度(du)(du)與細(xi)(xi)(xi)(xi)胞的(de)(de)酶促反(fan)應(ying)、信(xin)號(hao)傳導等(deng)代謝活(huo)動(dong)密切相關。準確探(tan)測(ce)細(xi)(xi)(xi)(xi)胞內(nei)的(de)(de)溫度(du)(du)變化(hua),不(bu)僅有(you)助于深化(hua)對(dui)細(xi)(xi)(xi)(xi)胞代謝活(huo)動(dong)規律的(de)(de)認(ren)識,而(er)且也具有(you)潛(qian)在(zai)的(de)(de)臨(lin)床上(shang)應(ying)用價值(zhi)。細(xi)(xi)(xi)(xi)胞尺度(du)(du)一(yi)般在(zai)微米(mi)量級,傳統的(de)(de)手(shou)段難以實現對(dui)細(xi)(xi)(xi)(xi)胞內(nei)溫度(du)(du)的(de)(de)探(tan)測(ce)。目前,細(xi)(xi)(xi)(xi)胞內(nei)溫度(du)(du)探(tan)測(ce)往(wang)(wang)(wang)往(wang)(wang)(wang)借(jie)助于納(na)(na)米(mi)溫度(du)(du)計——溫敏型納(na)(na)米(mi)發(fa)光探(tan)針(zhen)。然而(er),在(zai)進行細(xi)(xi)(xi)(xi)胞內(nei)溫度(du)(du)探(tan)測(ce)時(shi),現有(you)納(na)(na)米(mi)發(fa)光探(tan)針(zhen)的(de)(de)發(fa)光性質除受溫度(du)(du)影響(xiang)(xiang)外,往(wang)(wang)(wang)往(wang)(wang)(wang)還受細(xi)(xi)(xi)(xi)胞內(nei)復雜的(de)(de)生化(hua)環(huan)境(jing)(如:pH、離子強度(du)(du)等(deng))影響(xiang)(xiang)。而(er)細(xi)(xi)(xi)(xi)胞內(nei)的(de)(de)pH、離子強度(du)(du)等(deng)生化(hua)環(huan)境(jing)在(zai)時(shi)間(jian)(jian)、空間(jian)(jian)上(shang)是(shi)高(gao)度(du)(du)動(dong)態的(de)(de),嚴(yan)重影響(xiang)(xiang)了細(xi)(xi)(xi)(xi)胞內(nei)溫度(du)(du)探(tan)測(ce)的(de)(de)準確性和(he)可靠性。
在前期成(cheng)功構建高(gao)(gao)效量子(zi)點(dian)雙光(guang)子(zi)發光(guang)探(tan)針(P-QD)基(ji)礎上(Sci. Rep. 5, 9908; DOI:10.1038/srep09908),中國科學(xue)(xue)院遺傳與發育生(sheng)(sheng)物(wu)學(xue)(xue)研究(jiu)所(suo)降(jiang)(jiang)雨強課題組與北(bei)京大學(xue)(xue)教授沙印林課題組繼續深入合(he)(he)作。研究(jiu)發現(xian),在近生(sheng)(sheng)理(li)溫(wen)(wen)(wen)(wen)(wen)度(du)(du)(du)(du) (20-45 oC) 范(fan)圍內(nei)(nei)(nei),P-QD的發光(guang)強度(du)(du)(du)(du)隨溫(wen)(wen)(wen)(wen)(wen)度(du)(du)(du)(du)升高(gao)(gao)成(cheng)線性下(xia)降(jiang)(jiang),并且這種變(bian)(bian)(bian)化規(gui)律不受pH、離子(zi)強度(du)(du)(du)(du)的影響。基(ji)于(yu)P-QD的納(na)米(mi)溫(wen)(wen)(wen)(wen)(wen)度(du)(du)(du)(du)計(ji),檢(jian)測靈敏度(du)(du)(du)(du)高(gao)(gao)達0.43 oC;在pH 值(zhi)4到11范(fan)圍內(nei)(nei)(nei),納(na)米(mi)溫(wen)(wen)(wen)(wen)(wen)度(du)(du)(du)(du)計(ji)的發光(guang)強度(du)(du)(du)(du)變(bian)(bian)(bian)化小(xiao)于(yu)2%;當溶液的離子(zi)強度(du)(du)(du)(du)為(wei)500 mM(遠(yuan)高(gao)(gao)于(yu)生(sheng)(sheng)理(li)條件 ~100 mM)時,納(na)米(mi)溫(wen)(wen)(wen)(wen)(wen)度(du)(du)(du)(du)計(ji)的發光(guang)強度(du)(du)(du)(du)變(bian)(bian)(bian)化僅有2%。此外,該類(lei)(lei)納(na)米(mi)溫(wen)(wen)(wen)(wen)(wen)度(du)(du)(du)(du)計(ji)還(huan)具(ju)有很好的可(ke)逆(ni)性,溫(wen)(wen)(wen)(wen)(wen)度(du)(du)(du)(du)在25 oC和37 oC之(zhi)間交替(ti)變(bian)(bian)(bian)化100次,P-QD納(na)米(mi)探(tan)針的發光(guang)強度(du)(du)(du)(du)變(bian)(bian)(bian)化小(xiao)于(yu)5%。上述這些性質,結合(he)(he)其(qi)優異(yi)的生(sheng)(sheng)物(wu)相容性,使(shi)得P-QD可(ke)以作為(wei)一種理(li)想的細(xi)胞溫(wen)(wen)(wen)(wen)(wen)度(du)(du)(du)(du)探(tan)針。基(ji)于(yu)該類(lei)(lei)新型納(na)米(mi)溫(wen)(wen)(wen)(wen)(wen)度(du)(du)(du)(du)計(ji),實現(xian)了單個(ge)、活的腫瘤細(xi)胞內(nei)(nei)(nei)溫(wen)(wen)(wen)(wen)(wen)度(du)(du)(du)(du)變(bian)(bian)(bian)化準(zhun)確、靈敏探(tan)測。