Li Guodong, Gao Jianxin, Zhou Xiaojuan, Shimelis Olga, Giese Roger W
Department of Pharmaceutical Sciences, Bouve College of Health Sciences, Barnett Institute, Northeastern University, Boston, MA 02115, USA.
J Chromatogr A. 2003 Jul 4;1004(1-2):47-50. doi: 10.1016/s0021-9673(03)00855-0.
Near-infrared dyes are attractive as labeling reagents to enhance sensitivity in trace analysis largely because background fluorescence is low in this spectral region. Here we demonstrate, towards a goal of detecting DNA adducts in small biological samples, that some near-infrared (IR) dye-labeled deoxynucleotides can be separated and detected with high sensitivity by capillary electrophoresis (CE)-laser-induced fluorescence detection (LIF) in a realistic way (handling detection limit of 25 amol) for near-IR dye-labeled deoxynucleotides. This detection limit is achieved by polarity-switching injection of 2.0 microl from a volume of 5.0 microl, in which the compounds are 5 x 10(-12) mol/l in 50% aqueous methanol. Although the adenine and cytosine-containing conjugates co-migrated, the other three (guanine, N2-ethylguanine and thymine) were resolved.
近红外染料作为标记试剂在痕量分析中增强灵敏度很有吸引力，这主要是因为该光谱区域的背景荧光较低。在这里，为了实现检测小生物样本中DNA加合物的目标，我们证明，对于近红外染料标记的脱氧核苷酸，一些近红外（IR）染料标记的脱氧核苷酸可以通过毛细管电泳（CE）-激光诱导荧光检测（LIF）以实际可行的方式（25 amol的处理检测限）进行高灵敏度的分离和检测。该检测限是通过从5.0微升体积中极性切换进样2.0微升实现的，其中化合物在50%甲醇水溶液中的浓度为5×10⁻¹²摩尔/升。尽管含腺嘌呤和胞嘧啶的共轭物共迁移，但其他三种（鸟嘌呤、N2-乙基鸟嘌呤和胸腺嘧啶）被分离出来。
