Microfluidic chip electrophoresis has been widely employed for separation of various biochemical species owing to its advantages of low sample consumption, low cost, fast analysis, high throughput, and integration capability. In this article, we reviewed the development of four different modes of microfluidics‐based electrophoresis technologies including capillary electrophoresis, gel electrophoresis, dielectrophoresis, and field (electric) flow fractionation. Coupling detection schemes on microfluidic electrophoresis platform were also reviewed such as optical, electrochemical, and mass spectrometry method. We further discussed the innovative applications of microfluidic electrophoresis for biomacromolecules (nucleic acids and proteins), biochemical small molecules (amino acids, metabolites, ions, etc.), and bioparticles (cells and pathogens) analysis. The future direction of microfluidic chip electrophoresis was predicted.

Summary Current method for obtaining microbial colonies still relies on traditional dilution and spreading plate (DSP) procedures, which is labor‐intensive, skill‐dependent, low‐throughput and inevitably causing dilution‐to‐extinction of rare microorganisms. Herein, we proposed a novel ultrasonic spraying inoculation (USI) method that disperses microbial suspensions into millions of aerosols containing single cells, which lately be deposited freely on a gel plate to achieve high‐throughput culturing of colonies. Compared with DSP, USI significantly increased both distributing uniformity and throughput of the colonies on agar plates, improving the minimal colony‐forming abundance of rare Escherichia coli mixed in a lake sample from 1% to 0.01%. Applying this novel USI to a lake sample, 16 cellulose‐degrading colonies were screened out among 4766 colonies on an enlarged 150‐mm‐diameter LB plate. Meanwhile, they could only be occasionally observed when using commonly used DSP procedures. 16S rRNA sequencing further showed that USI increased colony‐forming species from 11 (by DSP) to 23, including seven completely undetectable microorganisms in DSP‐reared communities. In addition to avoidance of dilution‐to‐extinction, operation‐friendly USI efficiently inoculated microbial samples on the agar plate in a high‐throughput and single‐cell form, which eliminated masking or out‐competition from other species in associated groups, thereby improving rare species cultivability.