title: A compact 3D-printed interface for coupling open digital microchips with Venturi easy ambient sonic-spray ionization mass spectrometry.
abstract: Digital microfluidics (DMF) based on the electrowetting-on-dielectric phenomenon is a convenient way of handling microlitre-volume aliquots of solutions prior to analysis. Although it was shown to be compatible with on-line mass spectrometric detection, due to numerous technical obstacles, the implementation of DMF in conjunction with MS is still beyond the reach of many analytical laboratories. Here we present a facile method for coupling open DMF microchips to mass spectrometers using Venturi easy ambient sonic-spray ionization operated at atmospheric pressure. The proposed interface comprises a 3D-printed body that can easily be "clipped" at the inlet of a standard mass spectrometer. The accessory features all the necessary connections for an open-architecture DMF microchip with T-shaped electrode arrangement, thermostatting of the microchip, purification of air (to prevent accidental contamination of the microchip), a Venturi pump, and two microfluidic pumps to facilitate transfer of samples and reagents onto the microchip. The system also incorporates a touch-screen panel and remote control for user-friendly operation. It is based on the use of popular open-source electronic modules, and can readily be assembled at low expense.
authors.affiliation: Department of Applied Chemistry, National Chiao Tung University, Hsinchu 300, Taiwan. plurban@nctu.edu.tw.
authors.forename: Jie-Bi
authors.initials: JB
authors.lastname: Hu
authors.forename: Ting-Ru
authors.initials: TR
authors.lastname: Chen
authors.forename: Chia-Hsien
authors.initials: CH
authors.lastname: Chang
authors.forename: Ji-Yen
authors.initials: JY
authors.lastname: Cheng
authors.forename: Yu-Chie
authors.initials: YC
authors.lastname: Chen
authors.forename: Pawel L
authors.initials: PL
authors.lastname: Urban