A vortex chip is a small device that uses controlled swirling fluid motions, known as vortices, to precisely manage microscopic particles or cells. This technology is part of microfluidics, focusing on handling extremely small liquid volumes. It enables sample manipulation on a scale much smaller than traditional laboratory equipment.
These chips are designed to interact with minute quantities of substances, making them suitable for applications where sample volume is limited. Their ability to control fluid movement at the micro-scale allows for sophisticated handling of individual particles or cells. The contained environment offers a controlled setting for various biological and chemical processes.
How Vortex Chips Manipulate Fluids
Microfluidics involves controlling fluids within channels tens to hundreds of micrometers in size. Within these tiny channels, vortex chips generate swirling motions, or vortices, to influence the movement of suspended particles or cells. These vortices can be created through specific channel designs, such as sudden expansions or curved pathways, or by controlling the fluid flow rate.
Vortices can also be generated using micro-obstacles within the channel, which induce rotational flow patterns. These flows exert forces on particles, guiding their movement and positioning within the fluid. For instance, larger particles might be pushed towards the channel walls, while smaller ones remain in the center.
Fluid dynamics within these chips also involves phenomena like vortex shedding, where fluctuating forces act on objects, leading to predictable swirling patterns. Control over these fluid dynamics allows for various manipulations, including focusing particles into narrow streams, mixing different solutions, or trapping specific cells. By engineering these micro-scale fluid behaviors, vortex chips achieve specific and efficient particle control.
Separating and Sorting Biological Samples
Vortex chips leverage their fluid manipulation capabilities for the separation and sorting of biological samples. This is significant in biological research and medical diagnostics, where isolating specific cell types or purifying samples from complex mixtures is often required. For instance, in cancer liquid biopsies, isolating rare circulating tumor cells (CTCs) from billions of blood cells is a challenging yet crucial step for detection and analysis.
Vortex chips achieve this separation based on differences in the physical properties of particles or cells, such as size, density, or deformability. This is often accomplished by designing microcavities or expansion-contraction structures within the chip’s channels. These structures trap larger cells in generated vortices while allowing smaller cells to flow past.
Biological samples that can be processed include various cell populations, bacteria, and extracellular vesicles. Some vortex sorting chips use multiple parallel microchannels, each with numerous microcavities, allowing for simultaneous, high-throughput separation. This label-free method relies on physical interactions between particles and fluid forces, offering advantages like high concentration and retained cell viability.
Advancing Medical Diagnostics and Therapies
Vortex chip technology advances medical diagnostics and therapies by enabling more efficient sample processing. In diagnostics, these chips facilitate earlier disease detection by isolating rare biomarkers, such as circulating tumor cells (CTCs), from blood samples. Capturing these cells non-invasively, often with a simple blood draw, provides an alternative to more invasive traditional biopsies.
This technology also supports point-of-care testing, particularly in remote areas, by offering automated, low-cost, and high-throughput methods for sample preparation and analysis. For example, microfluidic chips can trap CTCs based on their size and deformability. This is beneficial since not all cancer cells express specific surface markers required for other labeling techniques. Isolated CTCs can then be used for downstream analysis, such as immunofluorescence staining or genomic sequencing, to provide insights into a patient’s cancer status and guide treatment decisions.
In therapeutic development and personalized medicine, vortex chips streamline drug screening processes and prepare cells for advanced cell therapies. By enabling the isolation of viable cells, the technology supports research into cancer cell biology and understanding metastasis. The captured cells can also be used for molecular analysis, which can inform targeted therapeutic treatments and patient stratification in clinical trials.