3D Generation of Multipurpose Atomic Force Microscopy Tips

Ayoub Glia

| July 5th 2022 – 11 am, NYUAD C1 (ERB) -045 |

Atomic force microscope (AFM) takes us for a dive into nanoscopic universe, where one can observe, measure and manipulate the micro and nanostructures present on any surface. The horizon of applications of AFM are limitless, ranging from imaging living bacteria and mammalian cells, analyzing DNA, filming functioning of proteins in real-time, and imaging molecules down to sub-atomic resolution. The AFM offers these fascinating possibilities with a probe (a cantilever beam with a needle at its end), which senses and feels sample surfaces through forces of attraction and repulsion, in the same way we use our fingertips. Existing commercial probes, however, are not suited for every application AFM can offer. For example, stiff probes are not applicable to soft samples such as cells as they would cause a hammer effect onto them. Moreover, some other more delicate AFM measurements require probes with specific design and material. In nowadays, commercial probes, which are silicon-based and fabricated with a process called micromachining, are limited by 2D designs and lengthy production steps. Thus, to bring flexibility in design, material, and function, the AMMLab researchers have now succeeded in developing a procedure to produce novel AFM probes, named 3DTIPs, by utilizing single-step 3D laser printing. 3DTIPs are superior to standard silicon-based probes in their 3D design, material of choice, and the variety of applications they can be utilized for. In this talk titled “3D Generation of Multipurpose Atomic Force Microscopy Tips”. Work that is accepted for publication in the Advanced Science journal, we presented a protocol for producing next generation AFM probes based on two-photon polymerization, where highly focused laser pulses are applied to solidify a light-sensitive, initially liquid epoxy material. As a result, the produced 3DTIPs are softer than the silicon-based counterparts, which makes them more suitable for AFM applications involving gentler interactions with cells, proteins and DNA molecules. Importantly, the material properties of 3DTIPs allow to achieve more than 100 times faster scans compared to silicon probes of similar dimensions. With a standard 3DTIP, the observation of millisecond biological events, such as the binding and jumping dynamics of certain proteins along the DNA strand is now possible. Noteworthy, the 3DTIPs are more immune to contamination and tip wear compared to their silicon-based counterpart probes. This means that the experiments can be conducted for longer periods using the same tip, which will help with reducing the inconsistencies related to changing probes during measurements.

Speaker’s Bio

Dr. Ayoub Glia joined the AMMLab, in January 2022, to work on advancing the technology of cryopreservable arrays of paper-based 3D tumor models. Previously, he was with the AMMLab as a PhD student (NYU), focusing on developing open microfluidic concepts and blending the concepts of Atomic Force Microscopy with Microfluidics. During his PhD, he developed the technology of the herringbone-based microfluidic probes, as well as developed multiple innovative AFM tips using 3D printing. Prior to the AMMLab, Ayoub was working for the military survey department in Abu Dhabi. Ayoub obtained his Master’s degree in Material Science and Engineering at Masdar Institute of Science and Technology, where his research domain was ranging from materials characterization to the development of vital AFM techniques.
Contact: ag6042@nyu.edu