Optical tweezers get smaller, sharper, and less expensive

Based on pioneering work in high-intensity, near-field laser structures, the Crozier lab developed two optical tweezers technologies that significantly reduced the size of the tweezers themselves, and the size of the objects that they can focus on. The nanoscale optical antennae technology reduced the size of the spot the tweezers can focus on; the Fresnel zone plate technology improved the focus ability. Together, these technologies miniaturized optical tweezers, enabling them to be produced using standard, microelectronic fabrication procedures.

Compared to current, bulky optical tweezers, Dr. Crozier’s new designs:
• Are significantly smaller, only a fraction of the size of current tweezers
• Use much less energy, two to three orders of magnitude less energy
• Cost much less
• Work with extremely small objects, such as bacteria and viruses, as well as large cellular samples
• Work with more sensitive biological samples


Researchers use optical tweezers to hold and manipulate microscopic objects, from the nanometer size to the single cell or molecule size. With these tweezers, researchers can isolate, measure, and sort small structures, including very small biological structures, such as DNA. They can also study and measure small forces within a cell to better understand how microscopic biological motors move and how they affect the biological structures around them.

Most optical tweezers require an extensive set of expensive laboratory hardware to support their use. Therefore, they are usually custom built for each use. Dr. Kenneth Crozier has implemented two technologies that have dramatically improved optical tweezers. With these improvements, Dr. Crozier could entirely change what they are used for, how they are used, who can buy them, and probably how they are built.

Because the optical tweezers are smaller and use less energy, they can be used with more devices, such as lab-on-a-chip systems, atomic force microscopy, nano-assembly, and patch-clamp analysis. Because the optical tweezers work with small objects, they can extend research to more complex and highly parallel studies and measurements of biological systems. Because they cost much less, they could be commercially built and sold.

Intellectual Property Status: Patent(s) Pending