Multi-step PDMS curing and a controlled separation method for mass manufacturing of high-performance and user-friendly micro-devices: valved micropumps.

Although valved micropumps have powerful performance, their popularized application is limited by high technical barriers and high costs brought by complex microstructures. Herein, we propose a multi-step PDMS curing method and a local PDMS separation strategy to achieve mass, standardized, and low-cost manufacturing of valved micropumps, solving their popularized problems by promoting role separation between manufacturers and users. The multi-step curing and the centralized structural layout enable a volume 20 times smaller than other valved micropumps.

Research of restricted migration evaluation of MDA-MB-231 cells in 2D and 3D co-culture models.

The restricted migration evaluation is conducive to more complex tumor migration research because of the conformity with tumors. However, the differences between restricted and unrestricted cell migration and the distinction between different evaluation methods have not been systematically studied, hindering related research. In this study, by constructing the restricted environments on chips, the influence of co-culture conditions on the cancer cell migration capacity was studied.

Advancements in the research of finger-actuated POCT chips.

Microfluidic point-of-care testing (POCT) chips are used to enable the mixing and reaction of small sample volumes, facilitating target molecule detection. Traditional methods for actuating POCT chips rely on external pumps or power supplies, which are complex and non-portable. The development of finger-actuated chips has reduced operational difficulty and improved portability, promoting the development of POCT chips.

Long-term cultured microvascular networks on chip for tumor vascularization research and drug testing.

The vascular structure of the tumor microenvironment (TME) plays an essential role in the process of metastasis. microvascular structures that can be maintained for a long time will greatly promote metastasis research. In this study, we constructed a mimicking breast cancer invasion model based on a microfluidic chip platform, and the maintenance time of the self-assembled microvascular networks significantly improved by culturing with fibroblasts (up to 13 days).

An integrated microchannel biosensor platform to analyse low density lactate metabolism in HepG2 cells .

In this study, we developed an electrochemical microchannel biosensor platform to analyse lactate metabolism in cells. This biosensor platform was fabricated by photolithography, thin-film deposition and microfluidic technology. A kind of functional biomaterial was prepared by mixing lactate oxidase, single-walled carbon nanotubes and chitosan, and platinum as working and blank electrodes of the biosensor was modified by a thin Prussian blue layer.

Three-dimensional microfluidic tumor-macrophage system for breast cancer cell invasion.

The recrudescence of breast cancer can partly be attributed to poor understanding of the early steps and the mechanisms involved in breast cancer metastasis, especially how tumor inflammatory cells including tumor-associated macrophages (TAM) affect invasion process. However, invasion-related biological studies in traditional in vitro assays or in vivo models are challenging due to the arduousness in establishing models that precisely reproduce the tumor invasion environment. To this end, we proposed a juxtaposed dual-layer cell-loaded hydrogels biomimetic microfluidic system and formed monolayer size-selective permeable vascular endothelial barriers besides the dual layer to mimic mammalian blood vessels.

A Novel Controllable Cell Array Printing Technique on Microfluidic Chips.

Goal: The construction of single-cell array is known as the challenging technology to manipulate cell position and number and accomplish cell analysis in biomedical engineering.

Methods: We put forward a novel controllable cell printing technique for rapid, precise, convenient, high cell viability, multicellular, and high-throughput printing. We also proposed a novel microfluidic device to verify the effectiveness of the printing and study the migration ability and anti-cancer drug responses of cancer cell as important applications.

An AC electrothermal self-circulating system with a minimalist process to construct a biomimetic liver lobule model for drug testing.

Liver-on-chip, due to its precision and low cost for constructing models, has tremendous potential for drug toxicity testing and pathological studies. By applying APAP (acetaminophen) treatment of different concentrations, a dynamic self-circulating liver lobule model for drug testing was proven useful for emulating the human physiological system. However, the demand for a dynamic system of on-chip organs is difficult to fulfil due to the relatively cumbersome fabrication processes.

The crossing and integration between microfluidic technology and 3D printing for organ-on-chips.

Organ-on-chips were designed to simulate the real tissue or organ microenvironment by precise control of the cells, the extracellular matrix and other micro-environmental factors to clarify physiological or pathological mechanisms. The organ chip is mainly based on the poly(dimethylsiloxane) (PDMS) microfluidic devices, whereas the conventional soft lithography requires a cumbersome manufacturing process, and the complex on-chip tissue or organ chip also depends on the complicated loading process of the cells and biomaterials. 3D printing can efficiently design and automatically print micrometre-scale devices, while bio-printing can also precisely manipulate cells and biomaterials to create complex organ or tissue structures.

Microfluidic system for modelling 3D tumour invasion into surrounding stroma and drug screening.

Tumour invasion into the surrounding stroma is a critical step in metastasis, and it is necessary to clarify the role of microenvironmental factors in tumour invasion. We present a microfluidic system that simulated and controlled multi-factors of the tumour microenvironment for three-dimensional (3D) assessment of tumour invasion into the stroma. The simultaneous, precise and continuous arrangement of two 3D matrices was visualised to observe the migration of cancer cell populations or single cells by transfecting cells with a fluorescent protein.

Construction of a liver sinusoid based on the laminar flow on chip and self-assembly of endothelial cells.

The liver is one of the main metabolic organs, and nearly all ingested drugs will be metabolized by the liver. Only a small fraction of drugs are able to come onto the market during drug development, and hepatic toxicity is a major cause for drug failure. Since drug development is costly in both time and materials, an in vitro liver model that can accelerate bioreactions in the liver and reduce drug consumption is imperative in the pharmaceutical industry.

Microfluidic co-culture system for cancer migratory analysis and anti-metastatic drugs screening.

Tumour metastasis is an important reason for cancer death, and cancer cell migration is an important step in the process of tumour metastasis. Studying cancer cell migration is of great significance. Here, we present a novel microfluidic co-culture system and establish mild, moderate and severe cancer models by using HMEpiC and MDA-MB-231 cells to study cancer cell migration and anti-cancer drug screening.