A practical interface for microfluidics and nanoelectrospray mass spectrometry

Abstract

We report a new method for fabricating nanospray ionization tips for MS, formed from glass substrates and the inert polymer, parylene-C. Using a single photolithography step, the emitters are formed contiguously with microchannels, such that no dead volumes are observed. In addition, because the devices are very thin (approximately 0.3 mm) and the tips are formed at rectangular corners, the Taylor cone volumes are small, which makes the method attractive for future integration with microfluidic separations. Device performance was demonstrated by evaluating diverse analytes, ranging from synthetic polymers, to peptides, to nucleic acids. For all analytes, performance was similar to that of conventional emitters (pulled-glass capillaries and the Agilent HPLC Chip) with the advantage of rapid, batch fabrication of identical devices.

A versatile microfluidic chip for millisecond time-scale kinetic studies by electrospray mass spectrometry

“…Conventional approaches for the fabrication of ECMDs include photolithography [21,22] and polymer imprint techniques [23,24]. Elegant, highly detailed microscale features can be generated using these methods, but they require specialized facilities, equipment, and expertise.…”

“…Elegant, highly detailed microscale features can be generated using these methods, but they require specialized facilities, equipment, and expertise. While efforts are being made to simplify photolithographic and polymer imprint fabrication [22], most protocols still require days to go from design to completion. In the present study, microchannels and the microfluidic mixer were formed by laser ablation using a VersaLaser engraving device.…”

Application of ’omics technologies to biomarker discovery in inflammatory lung diseases

“…However, despite the recent advances in mass spectrometry instrumentation, the speed of analysis is currently limiting and represents a key challenge for the future of clinical proteomics. Advances in the miniaturisation of front-end separations through nanospray microfluidics [79] may offer a solution to address this challenge, providing further increased sensitivity and sample throughput, an essential prerequisite for the advent of individualised protein biomarker discovery.…”

Microchip technology in mass spectrometry

“…8a). Another approach (Freire, Yang, & Wheeler, 2008) made use of two 150-mm-thick microscope slides that were bonded together in vacuum with the help of a parylene-C coating. The emitter tip took form in pursuance of the microchannel patterning on parylene-C since the channel outlet was directed at a rectangular corner of the chip (Fig.…”