German I, Buchanan D D, Kennedy R T
Department of Chemistry, University of Florida, Gainesville 32611-7200, USA.
Anal Chem. 1998 Nov 1;70(21):4540-5. doi: 10.1021/ac980638h.
A DNA aptamer against IgE was labeled with fluorophore and used as a selective fluorescent tag for determining IgE by capillary electrophoresis with laser-induced fluorescence detection (CE-LIF). CE-LIF separations of samples containing fluorescently labeled aptamer and IgE were complete in less than 60 s and revealed two zones, one corresponding to free aptamer and the other to aptamer bound to IgE. The free aptamer peak decreased and bound aptamer peak increased in proportion to the amount of IgE in the sample so that IgE could be detected with a linear dynamic range of 10(5) and a detection limit of 46 pM. The assay was highly selective as aptamer was unaffected by the presence of IgG and IgE did not bind other DNA sequences. IgE was determined in serum samples with similar analytical figures of merit. Similar conditions using a thrombin aptamer allowed detection of thrombin.
一种针对IgE的DNA适配体用荧光团标记，并用作选择性荧光标签，通过激光诱导荧光检测的毛细管电泳（CE-LIF）来测定IgE。含有荧光标记适配体和IgE的样品的CE-LIF分离在不到60秒内完成，显示出两个区域，一个对应游离适配体，另一个对应与IgE结合的适配体。游离适配体峰减少，结合适配体峰与样品中IgE的量成比例增加，因此可以在10(5)的线性动态范围内检测IgE，检测限为46 pM。该测定具有高度选择性，因为适配体不受IgG存在的影响，并且IgE不与其他DNA序列结合。在血清样品中测定IgE时具有相似的分析性能指标。使用凝血酶适配体的类似条件允许检测凝血酶。
