Yang Minli, Liu Chuanzhi, Qian Kejun, He Pingang, Fang Yuzhi
Department of Chemistry, East China Normal University, Shanghai.
Analyst. 2002 Sep;127(9):1267-71. doi: 10.1039/b205783b.
The electrogenerated chemiluminescence (ECL) behavior of N-(4-aminobutyl)-N-ethylisoluminol (ABEI) was studied and it was found that ABEI could produce emission light when oxidized at a +1.0 V (vs. Ag/AgCl) potential in alkaline solution. The addition of H2O2 markedly improved the ECL sensitivity. The pH value of the solution as well as the H2O2 concentration and working potential all have influences on the ECL response. Under optimal conditions, ABEI can be detected in the range 1.3 x 10(-6)-6.5 x 10(-12) mol L(-1). A detection limit of 2.2 x 10(-12) mol L(-1) for ABEI was obtained at a signal-to-noise ratio of 3. ABEI was then used as a marker to label a known sequence oligonucleotide, which was used as a DNA probe for identifying a target ssDNA immobilized on a PPy modified electrode based on a specific hybridization reaction. The hybridization events were evaluated by the ECL measurements. The results showed that only a complementary sequence could form a double-stranded DNA with the DNA probe and give a strong ECL response. A three-base mismatch sequence and non-complementary sequence have no response. The intensity of the ECL was linearly related to the concentration of the complementary sequence in the range 9.6 x 10(-11)-9.6 x 10(-8) mol L(-1), the detection limit was 3.0 x 10(-11) mol L(-1).
研究了N-(4-氨丁基)-N-乙基异鲁米诺(ABEI)的电化学发光(ECL)行为，发现ABEI在碱性溶液中于+1.0 V(相对于Ag/AgCl)电位下氧化时能产生发射光。加入H2O2显著提高了ECL灵敏度。溶液的pH值、H2O2浓度和工作电位均对ECL响应有影响。在最佳条件下，ABEI的检测范围为1.3×10(-6)-6.5×10(-12)mol L(-1)。在信噪比为3时，ABEI的检测限为2.2×10(-12)mol L(-1)。然后将ABEI用作标记物标记已知序列的寡核苷酸，该寡核苷酸用作DNA探针，基于特异性杂交反应识别固定在聚吡咯修饰电极上的目标单链DNA。通过ECL测量评估杂交事件。结果表明，只有互补序列才能与DNA探针形成双链DNA并产生强烈的ECL响应。三碱基错配序列和非互补序列无响应。ECL强度与互补序列浓度在9.6×10(-11)-9.6×10(-8)mol L(-1)范围内呈线性关系，检测限为3.0×10(-11)mol L(-1)。
