Cell analysis is one of the most popular directions for biological or biomedical researches and applications, such as tissue engineering and disease therapy, which usually focuses on single cell behavior, migration capability, surface protein expression and cell-cell communication. Based on the great development of microfluidic technique, cell analysis is integrated with lab on a chip (LOC) to enhance the analysis accuracy and reduce the amount of required sample. Even many excellent researches have been introduced, there are still some limitations need to be improved. For the implementation of multifunctional cell manipulation and analysis on a chip, specific microfluidic strategies have been proposed for cell/bacteria manipulation, isolation, mixing and neurulation.

In order to ensure the feasibility of cell manipulation with microflow, single cell manipulation strategy is introduced with a unique function of specific position control. Accurate single cell manipulation is required for cell analysis focusing on single cell behaviors and cell-cell communication. For position control, many researches have been conducted and corresponding manipulation platforms have been developed with good performances, but improvements are still required to further prevent the physical and chemical damages to cells. To reduce the negative impacts that cells may endure from confinement forces, a novel single-cell manipulation strategy is developed that uses boundary flow conditions to fulfill manipulation, while cell viability under flow shear stress is also analyzed.

Based on the ensurence of cell manipulation with microflow, unique cell isolation strategy is proposed focusing on rare cells. Rare cells are cell types which are highly important for various applications, such as the diagnosis and prognosis of many cancers, prenatal diagnosis and the diagnosis of viral infections. Even a lot of cell separation or sorting strategies have been introduced, accurate and high throughout isolation of rare cells, especially of cancer cells, should still be challenging. For the implementation of rare cell isolation with 100% isolation rate, a lab-on-a-chip microfluidic device consisting of a series of microtrappers arranged in a novel arrangement is developed for label-free rapid cancer cell isolation.

With the proposed cell isolation strategy, similar bacteria isolation is also developed. According to research reference, microbiome has been proved to play an important role in human health, but the degree of knowledge about the population distributions remains preliminary, due to the fact that a high proportion of the human microbiota remains unknown and has never been grown on account of the large bacterial diversity in microbiome. Based on this background, a high-throughput platform becomes a vital challenge for isolation, breeding and screening of bacterial strains from the microbial extracts under replicated microenvironmental conditions. A single-bacteria isolation and cultivation platform is proposed for human skin microbiome studies to evaluate which biological properties of the microbiome and host will yield important new insights in understanding human health and disease.

Besides position control and isolation/separation, microfluidic platform with mixing function is further designed for long-term cell/bacteria culture. Cell/bacteria culture is a critical problem for different kinds of cell researches and applications, and the cell/bacteria is eager to gather in the areas with high concentration of culture medium during the cell culture process. In order to conduct cell culture with uniform growth rates within the culture environment, a peristaltic microfluidic mixer is introduced to conduct cell culture with uniform growth rates in the culture environment by minimizing the difference of medium concentration.

Moreover, a novel microfluidic gradient generator is developed for the analysis of cell neurulation. Human embryonic stem cells (hESCs) have been proved as a unique tool for modeling human development, as they could form three dimensional tissue structures through self-organization, such as organoids which mimic the spatial characteristics of organs. However, gene studies using animal models or organoids fail to provide spatiotemporal dynamics of signaling and are difficult sometimes due to early termination of development. Thus a gradient generation device coupled with micropatterns is generated to recapitulate the main events during the process of neurulation: formation of the neural plate, shaping of the neural plate, bending of the neural plate and closure of the neural groove.

Compared with existing techniques, the introduced novel strategies show outstanding properties and provide great contributions to multiple cell researches and applications, such as cell-cell communication, cell sorting, cell differentiation, drug testing and even genetic investigation.