Induced Dual-Nanospray: A Novel Internal Calibration Method for Convenient and Accurate Mass Measurement

Abstract

Accurate mass information is of great importance in the determination of unknown compounds. An effective and easy-to-control internal mass calibration method will dramatically benefit accurate mass measurement. Here we reported a simple induced dual-nanospray internal calibration device which has the following three advantages: (1) the two sprayers are in the same alternating current field; thus both reference ions and sample ions can be simultaneously generated and recorded. (2) It is very simple and can be easily assembled. Just two metal tubes, two nanosprayers, and an alternating current power supply are included. (3)With the low-flow-rate character and the versatility of nanoESI, this calibration method is capable of calibrating various samples, even untreated complex samples such as urine and other biological samples with small sample volumes. The calibration errors are around 1 ppm in positive ion mode and 3 ppm in negative ion mode with good repeatability. This new internal calibration method opens up new possibilities in the determination of unknown compounds, and it has great potential for the broad applications in biological and chemical analysis.

Direct Analysis of Biofluids by Mass Spectrometry with Microfluidic Voltage-Assisted Liquid Desorption Electrospray Ionization

“…Methods deploying microfluidic chips with dual or multiple emitters for high through-put ESI-MS analysis or for improved accuracy in MS calibration were reported previously. 30–35 Compared with those microchips, a significant advantage of the present chip lies in that only a single ESI emitter is needed to achieve multiple sample analysis. Due to the simplicity in its design, the microchip is possible to make with cheap materials such as paper and glass, which is highly desirable for preparing disposable point-of-care microfluidic chips.…”

A pulsed pinhole atmospheric pressure interface for simplified mass spectrometry instrumentation with enhanced sensitivity

“…(d)). The capability of using multiple ionization sources also enables internal calibration for accurate mass measurements …”

Electric modeling and characterization of pulsed high‐voltage nanoelectrospray ionization sources by a miniature ion trap mass spectrometer

“…Based on this method, an induced dual nanospray was also reported by Nie as an internal calibration method for convenient and accurate mass measurements. 34 Besides the pulsed AC voltage used for induced nano-ESI, piezoelectric dispensing, 35,36 square wave supply, and pulsed DC high voltage [37][38][39][40][41] have also been employed for nano-ESI. Without sample electrode contact, a pulsed DC ESI could boost sample economy and has been successfully applied for single-cell metabolomic analysis.…”