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Wang, Daojing

Publications and source records attributed to Wang, Daojing.

Microfluidic devices for liquid chromatography-mass spectrometry and microscopic imaging

Systems, methods, and apparatus provide integration of microscopic imaging and liquid chromatography-mass spectrometry on a microfluidic device. In one aspect, an apparatus includes a first wafer, a second wafer, and an emitter. The emitter is disposed between the first wafer and the second wafer. The first wafer defines a sample input hole. The first wafer and the second wafer define a first channel, the first channel including a first end and a second end. The first end of the first channel is proximate the sample input hole. The first channel is configured to contain separation media. The second end of the first channel is proximate the emitter.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Senescence chips for ultrahigh-throughput isolation and removal of senescent cells

Cellular senescence plays an important role in organismal aging and age-related diseases. However, it is challenging to isolate low numbers of senescent cells from small volumes of biofluids for downstream analysis. Furthermore, there is no technology that could selectively remove senescent cells in a high-throughput manner. In this work, we developed a novel microfluidic chip platform, termed senescence chip, for ultrahigh-throughput isolation and removal of senescent cells. The core component of our senescence chip is a slanted and tunable 3D micropillar array with a variety of shutters in the vertical direction for rapid cell sieving, taking advantage of the characteristic cell size increase during cellular senescence. The 3D configuration achieves high throughput, high recovery rate, and device robustness with minimum clogging. We demonstrated proof-of-principle applications in isolation and enumeration of senescent mesenchymal stem cells (MSCs) from undiluted human whole blood, and senescent cells from mouse bone marrow after total body irradiation, with the single cell resolution. After scale-up to a multilayer and multichannel structure, our senescence chip achieved ultrahigh-throughput removal of senescent cells from human whole blood with an efficiency of over 70% at a flow rate of 300 ml/hr. Sensitivity and specificity of our senescence chips could be augmented with implementation of multiscale size separation, and identification of background white blood cells using their cell surface markers such as CD45. With the advantages of high throughput, robustness, and simplicity, our senescence chips may find wide applications and contribute to diagnosis and therapeutic targeting of cellular senescence.

59 BASIC BIOLOGICAL SCIENCES↗

Multinozzle emitter arrays for ultrahigh-throughput nanoelectrospray mass spectrometry

The present invention provides for a structure comprising a plurality of emitters, wherein a first nozzle of a first emitter and a second nozzle of a second emitter emit in two directions that are not or essentially not in the same direction; wherein the walls of the nozzles and the emitters form a monolithic whole. The present invention also provides for a structure comprising an emitter with a sharpened end from which the emitter emits; wherein the emitters forms a monolithic whole. The present invention also provides for a fully integrated separation of proteins and small molecules on a silicon chip before the electrospray mass spectrometry analysis.

42 ENGINEERING↗