Nanoelectrospray ionization (nESI) mass spectrometry (MS) is an ideal detection method for microfluidic chips, and its performances depend on nESI emitters. However, the fabrication of monolithic nESI emitters in chips was difficult. Herein, we propose a three-dimensional (3D) printing method to develop a microfluidic nanoelectrospray ionization source (NIS), composed of a nESI emitter and other components. Firstly, the NIS was compatible with a 50 – 500 nL min⁻¹ nanoflows by imposing 3D hydrodynamic focusing to compensate for the total flow rate, achieving a 7.2% best relative standard deviation in the total ion current (TIC) profiles. Additionally, it was applied to probe thirteen organic chemicals, insulin, and lysozyme with adequate signal-to-noise ratios and an accuracy of m/z between 9.02 × 10⁻¹ and 1.48 × 10³ ppm. Finally, the NIS achieved comparable limits of detection compared with its commercial counterpart. Considering the standardized preparation of NIS, it would be a potential option to develop 3D-printed customized Chip-MS platforms.

纳米电喷雾电离 (nESI) 质谱 (MS) 是一种理想的微流控芯片检测方法，其性能取决于 nESI 发射器。然而，在芯片中制造单片 nESI 发射器很困难。在此，我们提出了一种三维 (3D) 打印方法来开发由 nESI 发射器和其他组件组成的微流体纳米电喷雾电离源 (NIS)。首先，NIS通过施加 3D 流体动力学聚焦来补偿总流速，与 50 – 500 nL min ^-1纳流兼容，在总离子流 (TIC) 曲线中实现了 7.2% 的最佳相对标准偏差。此外，它还用于探测 13 种有机化学品、胰岛素和溶菌酶，具有足够的信噪比和m/z的准确度在 9.02 × 10 ^-1和 1.48 × 10 ³ ppm 之间。最后，NIS 实现了与其商业对应物相当的检测限。考虑到 NIS 的标准化制备，开发 3D 打印定制 Chip-MS 平台将是一个潜在的选择。