The sample capture range of classical optical tweezers is limited to micrometers. Scientists from the Massachusetts Institute of Technology were able to increase this value by orders of magnitude, which will forever change the work with biomaterials. Moreover, the device with the capture beam is located on a chip, and this is the path to mass and inexpensive production of portable biolabs.
Image source: Mit
«This work opens up new possibilities for chip-based optical tweezers, allowing cells to be captured and isolated over much greater distances than previously demonstrated. It’s interesting to think about the different applications that could be implemented with this technology,” said Jelena Notaros, MIT professor of electrical engineering and computer science (EECS).
Thanks to the new development, the range of the “tractor beam” has increased to 5 mm. It seems like a small thing? But compared to micrometers, this is a colossal progress and improvement. Previously, to manipulate biomaterials—DNA fragments or cells (optical tweezers are not designed for large objects)—samples had to be placed on glass slides, which compromised sterility and risked contamination. The MIT engineers’ device reaches so far that it can work with samples without removing them from sterile containers. Needless to say, this will speed up work and research? After all, you no longer need to waste time on measures to ensure sterility.
The researchers were able to achieve such an outstanding result when they presented an optical emitter on a chip in the form of a phased optical array. This ensured precise focusing and amplification of the beam over a longer range than with the much bulkier and more expensive traditional laser optical tweezers.
«With silicon photonics, we can take this large, typical laboratory [optical tweezers] system and integrate it into a chip. This is an excellent solution for biologists because it provides them with optical trapping and plucking capabilities without the added expense of a complex bulk optics setup,” explain the authors of the paper, published in the journal Nature Communications.