Microscopes fit within a miniaturized chip
In fact, they claim to be able to put tens of microscopes while working inside the chip.
Enlarged image of a single lens, in practice, one of the "microscopic" the biochip. [Image: Ken Crozier]
The breakthrough, which represents the marriage of high-performance optics with microfluidics, may be the perfect combination to make the on-chip technology more powerful and more practical.
Microfluidic devices are able to filter and automatically mix the chemicals, making them ideal for detection of diseases and environmental monitoring . But the performance of these devices may be even greater if they are provided with miniature microscopes in its interior, which allows them to analyze biological samples even smaller and more accurately.
The board optical detection now presented by researchers at Harvard create a microfluidic device for parallel processing fully capable of analyzing almost 200,000 droplets per second sample.
The researchers said their device is scalable and reusable and can be easily adapted for different types of analysis.
“In essence, we integrate a high-performance optics on a chip that also contains microfluidics. This allows us to parallelize the optics in the same way a microfluidic device that parallels the handling of samples,” said Ken Crozier, research coordinator.
Each of the circles is a lens by observing the different microchannels of a biochip. [Image: Ken Crozier]
Unlike a typical optical detection system, which uses the objective lens of a microscope to examine a single location within a microfluidic channel, the new board is designed to detect light coming from multiple channels simultaneously.
In its statement, an array of 62 lenses, built on a silicon plate a measured fluorescence signal drops by 62 canals that were circulating of a highly parallelized microfluidic device.
The device works by creating a focused point of excitation within each microchannel array and then collects the resulting fluorescence emission of droplets that travel through the microchannel, literally taking pictures of the droplets as they pass.
The series of images is recorded by a digital camera sensor, enabling high-speed observation of all channels simultaneously. As each set is designed to collect the fluorescence of a well-defined region of the microchannel, it avoids interference between adjacent channels.
The end result is a film of droplets flowing swiftly through the channels, something impossible to do with the present microscope, due to their narrow field of vision.
“As we have this massively parallel approach – effectively as if we have 62 microscopes – we can obtain many measurements at the same time,” said Crozier. “This device proved capable of measuring up to 200,000 drops per second, but I think we can do even more.”