Development of high-resolution multidimensional native protein microfluidic chip electrophoresis fingerprinting and its application in the quick analysis of unknown microorganisms

The unascertained, constant mutation and emergence of new types of microorganisms present significant challenges to their detection. Differing from the focus on the limited local 16S rRNA gene or protein markers, characteristic whole fingerprint technologies at the omic level are particularly suitable for unknown analytes since accurate knowledge about the constituents is not necessarily required. Herein, through a combination of several innovative strategies, including pure water isotachophoresis integrated (2 + 1)D electrophoresis, inversion-funnel peak stacking channel geometry and COMSOL computer-aided fluid simulation, high-resolution whole protein 2D native microfluidic chip electrophoresis was achieved within less than 1 min. The highest ever reported peak capacity for native 2D chip electrophoresis was obtained. Furthermore, taking Escherichia coli, Staphylococcus aureus, and Bacillus subtilis as model analytes without protein biomarker information, the feasibility of the identification and semiqualification of unknown microbes in pure or mixed samples was explored with the utilisation of original algorithms, including SIFT feature abstraction and a global information entropy combined support vector machine. As such, the multidisciplinary cooperation in the present study demonstrates monstrated promising prospects for microfluidic chip electropherogram fingerprint-based quick microorganism assays, biointeraction studies, and drug screenings, even if the analytes are not fully ascertained.