Multiplexed proteomic sample preconcentration device using surface-patterned ion-selective membrane (original) (raw)
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Journal of Microelectromechanical Systems, 2011
We report on a fabrication and packaging process for a microsystem consisting of a mass-based protein detector and a fully integrated preconcentrator. Preconcentration of protein is achieved by means of a nanofluidic concentrator, which takes advantage of fast non-linear electro-osmotic flow near a nanochannel-microchannel junction to concentrate charged molecules inside a volume of fluid on the order of one picoliter. Detection of preconcentrated protein samples is accomplished by passing them through a suspended microchannel resonator, which is a hollow resonant cantilever serially connected to the nanofluidic concentrator on the same device. The transit of a preconcentrated sample produces a transient shift in the cantilever's resonance frequency proportional to the density of the sample, and hence the concentration of protein contained in it. A device containing both nanofluidic concentrator and suspended microchannel resonator structures was produced using a novel fabrication process which simultaneously satisfies the separate packaging requirements of the two structures. Initial testing of this prototype device has demonstrated that the integrated suspended microchannel resonator can accurately measure the concentration of a bovine serum albumin sample which was preconcentrated using the integrated nanofluidic concentrator. Future improvements in the fabrication process will allow site-specific surface modification of the device and compatibility with separation methods, which will create opportunities for its application to immunoassays and universal detection.
Microfluidic systems in proteomics
…, 2003
We present the state-of-the-art in miniaturized sample preparation, immunoassays,one-dimensional and multidimensional analyte separations, and coupling of micro-devices with electrospray ionization-mass spectrometry. Hyphenation of these differ-ent techniques and their relevance to proteomics will be discussed. In particular, we will show that analytical performances of microfluidic analytical systems are alreadyclose to fulfill the requirements for proteomics, and that miniaturization results at thesame time in a dramatic increase in analysis throughput. Throughout this review,some examples of analytical operations that cannot be achieved without micro-fluidics will be emphasized. Finally, conditions for the spreading of microanalyticalsystems in routine proteomic labs will be discussed.
Analytical Chemistry, 2005
The present investigation describes the analytical performances of a microfluidic device comprising an enrichment column, a reversed-phase separation channel, and a nanoelectrospray emitter embedded altogether in polyimide layers. This configuration minimizes transfer lines and connections and reduces postcolumn peak broadening and dead volumes. This compact and versatile modular nanoLC-chip system was interfaced to both ion trap and time-of-flight mass spectrometers, and its analytical potentials were evaluated in the context of proteomics applications. The figures of merit of this system in terms of peak capacity, reproducibility, sensitivity, and linear dynamic range of peptide detection were determined using tryptic digests of complex protein extracts including albumin-and immunoglobulin-depleted rat plasma samples. The analysis of peak profiles for more than 600 peptide ions reproducibly detected across replicate nanoLC-chip-MS runs (n ) 10) indicated that this system provided good reproducibility of retention time and peak intensity with RSD values of less than 0.5 and 9.1%, respectively. Variation in peptide abundance as low as 2-fold changes was identified for spiked tryptic digests present at levels of 2-5 fmol in plasma samples. Sensitivity measurements were performed on dilution series of protein digests spiked into rat plasma samples and provided a detection limit of 1-5 fmol. The modular concept of the microfluidic systems also facilitated the integration of two-dimensional chromatography (strong cation exchange/C 18 ) thereby increasing the sample loading and selectivity of the nanoLC-chip-MS system. The application of this integrated device was evaluated for complex rat plasma samples to compare the number of protein identifications obtained using one-and twodimensional nanoLC-chip-MS/MS. Zhou, H.; Lin, H.; Roy, S.; Shaler, T. A.; Hill, L. R.; Norton, S.; Kumar, P.; Anderle, M.; Becker, C. H. Anal. Chem. 2003, 75, 4818-4826. (9) Radulovic, D.; Jelveh, S.; Ryu, S.; Hamilton, T. G.; Foss, E.; Mao, Y.; Emili, A. Mol. Cell. Proteomics, in press.
Sensors and Actuators B: Chemical, 2008
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Microfluidics for the analysis of membrane proteins: How do we get there?
ELECTROPHORESIS, 2014
Microfluidics for the analysis of membrane proteins: How do we get there? The development of fully automated and high-throughput systems for proteomics is now in demand because of the need to generate new protein-based disease biomarkers. Unfortunately, it is difficult to identify protein biomarkers that are low abundant when in the presence of highly abundant proteins, especially in complex biological samples such as serum, cell lysates, and other biological fluids. Membrane proteins, which are in many cases of low abundance compared to the cytosolic proteins, have various functions and can provide insight into the state of a disease and serve as targets for new drugs making them attractive biomarker candidates. Traditionally, proteins are identified through the use of gel electrophoretic techniques, which are not always suitable for particular protein samples such as membrane proteins. Microfluidics offers the potential as a fully automated platform for the efficient and high-throughput analysis of complex samples, such as membrane proteins, and do so with performance metrics that exceed their bench-top counterparts. In recent years, there have been various improvements to microfluidics and their use for proteomic analysis as reported in the literature. Consequently, this review presents an overview of the traditional proteomic-processing pipelines for membrane proteins and insights into new technological developments with a focus on the applicability of microfluidics for the analysis of membrane proteins. Sample preparation techniques will be discussed in detail and novel interfacing strategies as it relates to MS will be highlighted. Lastly, some general conclusions and future perspectives are presented.
Chip-based microfluidic devices coupled with electrospray ionization-mass spectrometry
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Chip-based microfluidic devices coupled with electrospray ionization-mass spectrometry We present the current status of the development of microfluidic devices fabricated on different substrates for coupling with electrospray ionization-mass spectrometry (ESI-MS). Until now, much success has been gained in fabricating the ESI chips, which show better performances due to miniaturization when compared with traditional methods. Integration of multiple steps for sample preparation and ESI sample introduction, however, remains a great challenge. This review covers the main technical development of electrospray device that were published from 1997 to 2004. This article does not attempt to be exclusive. Instead, it focuses on the publications that illustrated the breath of the development and applications of microchip devices for MS-based analysis.
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Analytical Chemistry, 2005
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