The Advanced Microfluidics and Microdevices Laboratory (AMMLab) at NYU Abu Dhabi has created a new class of atomic force microscopy (AFM) probes known as 3DTIPs that have actual three-dimensional forms.
With remarkable accuracy, AFM technology enables researchers to examine, quantify, and alter materials and entities at the micro- and nanoscale. The new 3DTIPs can be used for a larger range of applications — and possible observations and discoveries — than ordinary, more constrained silicon-based probes.
They are produced utilizing a single-step 3D printing method.
The outstanding resolutions achieved by atomic force microscopy (AFM), which can characterize materials by physically traversing a probe across surfaces, are 1,000 times greater than those of optical microscopy.
AFM is a key tool in many fields, including the biomedical sciences, and has a wide range of uses, including the characterization of living bacteria and mammalian cells, DNA molecule analysis, real-time protein analysis, and sub-atomic resolution imaging of molecules.
The technology’s core component is the AFM probe, which consists of a thin cantilever beam with a microscopic tip at one end. Similar to how human fingers perceive and feel sample surfaces through forces of attraction and repulsion, it does so with an atomic-level degree of detail.
Commercial AFM probes are produced from silicon using traditional semiconductor manufacturing techniques that are used in the microelectronics sector but are constrained by 2D designs and labor-intensive fabrication procedures.
These modern, cutting-edge probes are hard, fragile, and limited in their design options. They are not the best for examining soft materials, such as mammalian cells.
The researchers describe their unique method for creating next-generation AFM probes based on two-photon polymerization 3D printing in their study titled “3D Generation of Multipurpose Atomic Force Microscopy Tips,” which was published in the journal Advanced Science.
In comparison to their silicon-based predecessors, the generated 3DTIPs are softer, making them more appropriate for AFM applications that involve gentler interactions with molecules of DNA, proteins, and cell membranes.
Importantly, the 3DTIPs’ unique material characteristics enable scans that are more than 100 times quicker than those of conventional silicon probes of comparable size. As a result, 3DTIPs could make it possible to obtain real-time videos of the bioactivities of proteins, DNA, and even smaller molecules.
We have developed a novel technology for next-generation AFM probes with new materials, improved designs and production processes, novel shapes in 3D, and customized prototyping for a seamless production cycle for application-focused AFM probes. The ability to generate customized AFM probes with innovative 3D designs in a single step provides endless multidisciplinary research opportunities.
Mohammad Qasaimeh, Project Principal Investigator and Associate Professor, Mechanical Engineering and Bioengineering, New York University Abu Dhabi
Dr. Ayoub Glia, the first author of the study and postdoctoral associate at the AMMLab, stated, “Our 3DTIPs are capable of obtaining high-resolution, high-speed AFM imaging using common AFM modes, and under air and liquid environments. Refining the tip end of the 3DTIPs by focused ion beam etching and carbon nanotube inclusion substantially extends their functionality in high-resolution AFM imaging, reaching angstrom scales.”
The study’s authors believe that the 3DTIPs’ multifunctional properties will enable the introduction of next-generation AFM tips to both fundamental and novel AFM applications, as well as the development of high-speed AFM imaging and biological force measurements.
Financial support for the study came from NYU Abu Dhabi, the UAE’s NYU Abu Dhabi Research Enhancement Fund, and Terry Fox Foundation International Run Program in Vancouver, Canada.
Glia, A., et al. (2022) 3D Generation of Multipurpose Atomic Force Microscopy Tips. Advanced Science. doi:10.1002/advs.202201489.