Lab-on-a-chip (LOC) refers to a miniature device that brings together multiple laboratory functions on a single, handheld platform. These credit-card-sized chips act as fluidic integrated circuits, where liquid samples flow through microchannels etched into the devices that allow for mixing and separating fluids, facilitating chemical reactions and analyzing substances. In other words, they can perform several tasks traditionally reserved for full-fledged laboratories.
What Is Lab-on-a-Chip?
Lab-on-a-chip is a miniature device that integrates multiple laboratory functions onto a single microscale platform. It’s portable and convenient, and is commonly used for medical diagnostics, point-of-care testing and even environmental monitoring.
Pregnancy tests, Covid-19 tests and blood-glucose tests are some everyday examples of lab-on-a-chip technology.
What Is Lab-on-a-chip?
Lab-on-a-chip technology crams an entire lab’s worth of functions into a tiny device roughly the size of a USB stick. This palm-sized device — etched with tiny channels that can manipulate fluids at the microscopic level — offers insight to the inner workings of the human physiological process.
By condensing benchtop operations into a chip, biochemists bend scaling laws in their favor, where viscous forces become the dominant forces. This gives biochemists more control, where they can test single-cell reactions, and “fluids kind of go where you want them to,” Siavash Ahrar, an assistant professor of biomedical engineering at California State University, Long Beach, explained. “Miniaturization helps [biochemists] handle material at scale, where they can ask questions that are very difficult or, in some cases, impossible to ask.”
The main purpose of lab-on-a-chip technology is to improve access to bring medical tests “closer to the point of care or in everyone’s home and with fast response,” Stefano Begolo, director of microfluidic engineering at lab-on-a-chip product manufacturer ALine, told Built In. “It would democratize access to healthcare for everyone, especially in remote settings that are currently underserved.”
How Does Lab-on-a-chip Work?
Lab-on-a-chip is powered by microfluidics, which is all about observing how fluids react when they are injected into these tiny devices.
In order to work, lab-on-a-chip systems rely on laminar flow. This means that, on such a small scale, fluids move in smooth, parallel lines without mixing. Each particle follows behind the preceding one in predictable streams with minimal turbulence.
When fluids are loaded into a lab-on-a-chip cartridge to be analyzed, they are processed by on-board components — valves, pumps and sensors — as they move through a network of microchannels etched into the chip. Actuators pull the liquid through the device, where it undergoes a serial dilution phase. This step introduces a series of inputs, like reagents, that test and chemically react with sample fluid. Particles that differ in size separate, creating different output results that can be read on a built-in display.
Typically, lab-on-a-chip devices are connected to an external, refrigerator-sized computer. But pneumatic models truer to the name are in the making, like one Ahrar and his colleagues engineered that runs on air and comes with all components — including a computer and power supply — built into the chip itself.
Lab-on-a-chip Use Cases
Point-of-Care Diagnostics
Lab-on-a-chip tech enables rapid diagnosis with high precision at the point of care, outside of traditional laboratory settings. The primary use case for these chips is for detecting infectious diseases, monitoring biomarkers and performing routine tests at rapid speeds.
Drug Discovery
Lab-on-a-chip devices are known for their high-throughput screening capabilities. In pharmaceutical research, this is used to explore drug candidates, create personalized drug profiles per patient and assess drug efficacy as well as its toxicity. This tech offers researchers a window into drug interactions in order to optimize formulations and accelerate the drug-development process.
Biochemical Analysis
Lab-on-a-chip is used in a number of biochemical and chemical processes, from DNA sequencing to environmental monitoring. They offer automation, portability and high sensitivity when testing, which allows for complex analyses with minimal sample and reagent consumption.
Regenerative Medicine
These models are designed to recreate the microenvironment of tissues and organs as a way to study cell behavior and tissue development. They’re used to culture and manipulate cells in three-dimensional environments, mimicking the conditions found in vivo. This enables the development of tissue-engineered constructs for regenerative medicine applications, such as organoids, scaffolds and artificial organs.
Examples of Lab-on-a-chip Devices
Home Tests
Pregnancy tests, Covid-19 tests and blood-glucose-monitoring strips are several everyday examples of microfluidics. They use disposable, lateral flow systems that deliver results on site and with a quick turnaround time of a couple minutes or less, democratizing access to healthcare services by eliminating the need to send results out to a centralized laboratory.
Organ-on-a-chip
While still considered an emerging field, lab-on-a-chip technology has developed enough to deliver bio-inspired micro-devices that mimic whole human organ function. Injected with living cells, organ-on-a-chip cartridges provide fully functional cross sections of complex organ structures to develop novel therapies at lower costs and rapid speeds. Today, biomimetic models of human hearts, lungs, liver, kidneys, intestines and brain are in the making.
Heart-on-a-chip
Researchers at the University of California, Berkeley, are bioengineering a heart-on-a-chip device using induced pluripotent stem cells. It generates nutrients and oxygen to keep the cells alive, producing an unlimited supply of tissue-building donor cells as well as a regular heartbeat.
Lung-on-a-chip
Scientists at the Wyss Institute at Harvard University are bioengineering a flexible, polymer-based chip that mimics the mechanical and chemical function of a human lung. Lined with human lung and capillary blood vessel cells, this lab-on-a-chip device combines cyclic suction with side vacuum channels to “breathe,” and can replicate the toxic impact of airborne nanoparticles on respiratory health.
Liver-on-a-chip
As part of a National Institute of Health-funded clinical trial program, a team at the University of Pittsburgh have created a liver-on-a-chip device using four different cell types as well as fluorescent biosensors that visually indicate fluctuations in cell function. This biomimetic replica generates biochemical and metabolic information, and aims to create therapies for metabolic dysfunction and type-two diabetes.
Tumor-on-a-chip
Biopsied tumor cells can be cultured in tumor-on-a-chip devices, designed to mimic a tumor’s microenvironment, to test their response to treatments. By recreating a tumor’s biology, researchers are able to capture a closer look at the metastatic process, studying the physical and biochemical cues encountered by cancer cells in vivo.
Advantages of Lab-on-a-chip Technology
Miniaturization
Shrinking lab operations down to the microscale gives researchers better control over experiments. At this scale, liquids become the dominating forces. Thanks to unique properties like laminar flow, things like singular cell reactions become possible.
Speed
Lab-on-a-chip cartridges can be designed to perform a number of laboratory functions. This not only produces speedy results — typically in 30 minutes or less — but, at such a small scale, reactions happen faster.
“People don’t want to wait for results,” microfluidics and chemical engineer Manasi Raje said, noting the benefits to both patients and investors.
Small Sample Volumes
Lab-on-a-chip cartridges require small input volumes — in the micro-to-nanoliter range — which reduces the amount of sample needed for analysis. This is especially beneficial when working with important materials, such as those biopsied from a patient, like blood or tumor cells.
Low Cost
Given their size, these micro-devices use less material. They also cut back on resources required to run conventional lab methods, including equipment and labor costs. Stanford University researchers produced a reusable lab-on-a-chip device for as little as one penny.
Accessibility
Lab-on-a-chip allows deployment of diagnostics outside of the standard lab environment. An on-the-go method creates greater access to treatment for everyday people as well as small rural health care centers in developing nations, Raje explained.
“This technology puts the power of big, heavily funded labs into the hands of people who don't have a lot of resources,” Raje, who worked alongside Ahrar in developing a pneumatic lab-on-a-chip device, said. “You don’t need electricity for [a pneumatic device]. You don't need to buy a big pump or pro computer. You don’t even need to understand the science — you can just buy a small chip.”
Reduced Animal Testing
All applications of lab-on-a-chip technology share a common goal — to eliminate animal testing. Even though it’s considered a common practice in the biochemical field, using live animal tissue is high cost, laborious, riddled with ethical setbacks and may even fail to accurately predict how a human would respond to a drug due to physiological differences in the end.
Disadvantages of Lab-on-a-chip Technology
Complex Microfabrication
Each lab-on-a-chip device is etched with an intricate design that represents several integrated systems. So while these models may fit in the palm of your hand, they still go through a highly technical, labor-intensive micro-fabrication process that restricts their scalability as a mass-market product.
Complications
When benchtop operations are downsized to a microchip, components become smaller and processes more concentrated. Every factor, from the smoothness of a chip’s surface to a liquid's flow rate as it moves through a lab-on-a-chip device, impacts test results to a higher degree than they would during traditional, gold standard methods, Begolo said. As the significance of interactions between physical and chemical phenomena increases, so does the potential of micro-scale-related complications.
Standardization
Microfluidics, as a formal discipline, has only been around for about two decades. As an emerging technology, lab-on-a-chip tech falls behind its peers in well-established areas, like electrical systems, which benefit from about a century of standardization. So while lab-on-a-chip devices are commonly compared to electrical circuits, the analogy only goes so far, Ahrar said.
“Transporting fluids is much harder than transporting electricity,” Ahrar said. “Every person who has worked on microfluidics learns this the hard way.”
Frequently Asked Questions
What does lab-on-a-chip mean?
Lab-on-a-chip refers to compact, wet-ware devices capable of performing a number of laboratory functions on a single, palm-sized platform.
What are the benefits of lab-on-a-chip?
Lab-on-a-chip offers fast results at high throughput, smaller sample sizes, lower costs, increased point-of-care accessibility without the need for a centralized lab and reduced animal testing.
How much does a lab-on-a-chip cost?
While there are numerous lab-on-a-chip variations made out of different materials, Stanford scientists found a way to produce a diagnostic micro-device for as little as one cent.
