Wu Z, Tong W G
Department of Chemistry, San Diego State University, CA 92182, USA.
J Chromatogr A. 1997 Jun 27;773(1-2):291-8. doi: 10.1016/s0021-9673(97)00185-4.
Forward-scattering four-wave mixing is demonstrated as a sensitive absorbance detection method for capillary electrophoresis, using an argon ion laser operating at 457.9 nm. Since this four-wave mixing laser technique utilizes only two input laser beams, it offers important advantages, including ease of optical alignment, high wave-mixing efficiency and low excitation power requirements. In addition, since the analytical signal is a laser-like coherent beam, highly efficient optical signal detection can be performed with minimum optical background noise. Excellent detection sensitivity and short absorption path lengths, and hence, small detector probe volumes, are some of the useful features this absorbance detection method offers for on-column detection of both fluorescing and non-fluorescing analytes in capillary electrophoresis and liquid chromatography. Preliminary "detected" concentration detection limit of 8.5.10(-8) M, mass detection limit of 13 amol and an absorbance-unit detection limit of 1.35.10(-5) AU are determined for dabsyl-glycine using this absorbance detection method.
利用波长为457.9nm的氩离子激光器,前向散射四波混频被证明是一种用于毛细管电泳的灵敏吸光度检测方法。由于这种四波混频激光技术仅使用两束输入激光束,因此具有诸多重要优势,包括易于光学对准、高波混频效率以及低激发功率要求。此外,由于分析信号是类似激光的相干光束,因此可以在最小光学背景噪声的情况下进行高效的光信号检测。出色的检测灵敏度、短吸收路径长度以及由此产生的小检测探头体积,是这种吸光度检测方法在毛细管电泳和液相色谱中对荧光和非荧光分析物进行柱上检测时所具有的一些有用特性。使用这种吸光度检测方法,确定了达布西尔 - 甘氨酸的初步“检测”浓度检测限为8.5×10⁻⁸M,质量检测限为13 amol,吸光度单位检测限为1.35×10⁻⁵AU。