Suprapto James, Tong William G
Department of Chemistry and Biochemistry, San Diego State University, San Diego, CA, 92182, USA.
Department of Chemistry and Biochemistry, San Diego State University, San Diego, CA, 92182, USA.
Talanta. 2023 Feb 1;253:123859. doi: 10.1016/j.talanta.2022.123859. Epub 2022 Aug 22.
Nonlinear laser wave-mixing spectroscopy is demonstrated as a fast and sensitive detection method for heart-failure biomarkers, pro-atrial natriuretic peptide (proANP) and brain natriuretic peptide (BNP). Wave mixing is an ultrasensitive optical absorption-based method and analytes can be detected in their native form or labeled with fluorophore and chromophore labels. In this study, we utilized Chromeo P540 dye to label the peptides for wave-mixing detection. The wave-mixing signal is created from the diffraction of incoming photons by the thermal grating at the capillary analyte cell. The signal beam is strong, collimated, and coherent (laser-like) and it is collected using a simple photodetector with an excellent signal-to-noise ratio. We demonstrated advantages of this technique over conventional assays including shorter analysis times, smaller sample requirements, and higher throughput. To enhance detection selectivity and sensitivity levels, wave mixing is effectively coupled to capillary zone electrophoresis (CZE) and field-amplified sample stacking (FASS) methods. We determined detection limits of 7.4 × 10 M or 55 zmol and 6.8 × 10 M or 51 zmol for proANP and BNP, respectively, and separated and detected both peptides within 2 min. Due to the challenges in the confirmatory diagnoses of heart failure, wave-mixing serves as a potentially beneficial screening tool in addition to the commonly used echocardiographic tests.
非线性激光波混频光谱法被证明是一种用于检测心力衰竭生物标志物——前心钠素（proANP）和脑钠素（BNP）的快速且灵敏的检测方法。波混频是一种基于超灵敏光吸收的方法，分析物可以以其天然形式进行检测，也可以用荧光团和发色团标记物进行标记。在本研究中，我们使用铬菁P540染料标记肽段以进行波混频检测。波混频信号是由毛细管分析物池中热光栅对入射光子的衍射产生的。信号光束很强、准直且相干（类似激光），并且使用具有出色信噪比的简单光电探测器进行收集。我们证明了该技术相对于传统检测方法的优势，包括更短的分析时间、更小的样品需求和更高的通量。为了提高检测的选择性和灵敏度，波混频有效地与毛细管区带电泳（CZE）和场放大样品堆积（FASS）方法相结合。我们分别测定了proANP和BNP的检测限为7.4×10⁻⁹ M或55 zmol以及6.8×10⁻⁹ M或51 zmol，并在2分钟内分离并检测了这两种肽段。由于心力衰竭确诊存在挑战，除了常用的超声心动图检查外，波混频可作为一种潜在有益的筛查工具。
