Simultaneous pre-concentration and separation on simple paper-based analytical device for protein analysis
In this work, fast isoelectric focusing (IEF) was successfully implemented on an open paper fluidic channel for simultaneous concentration and separation of proteins from complex matrix. With this simple device, IEF can be finished in 10 min with a resolution of 0.03 pH units and concentration factor of 10, as estimated by color model proteins by smartphone-based colorimetric detection. Fast detection of albumin from human serum and glycated hemoglobin (HBA1c) from blood cell was demonstrated. In addition, off-line identification of the model proteins from the IEF fractions with matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS) was also shown. This PAD IEF is potentially useful either for point of care test (POCT) or biomarker analysis as a cost-effective sample pretreatment method.
KeywordsIsoelectric focusing (IEF) Paper-based analytical device (PAD) Point-of-care test (POCT) Protein sample pretreatment
Following financial supports are acknowledged: National Natural Science Foundation of China (21575019), Education Department of the Liaoning Province of China (LZ2015036), National Basic Research Program of China (2014CBA02003), Novo Nordisk-Chinese Academy of Sciences Research Fund (NNCAS-2015-11), and the Strategic Priority Research Programs of the Chinese Academy of Sciences (XDA12030202).
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Conflict of interest
The authors declare that they have no conflict of interest.
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