High-speed atomic force microscopy combined with a laser irradiation system for the in-situ real-time observation of azo-polymer contortion procedure. Credit: Osaka UniversityExpanding our clinical understanding typically boils down to getting as close an appearance as possible at what is happening. Now researchers from Japan have observed the nanoscale behavior of azo-polymer films while activating them with laser light.In a study recently published in Nano Letters the scientists from Osaka University used tip-scan high-speed atomic force microscopy (HS-AFM) combined with an optical microscope to develop motion pictures as the polymer films changed.The Significance of Azo-PolymersAzo-polymers are photoactive products, meaning they undergo changes when light is shined on them. Specifically, light changes their chemical structure, which alters the surface of the films. This makes them intriguing for applications such as optical data storage and providing light-triggered motion.Being able to start these modifications with a focused laser light while recording images is known as in situ measurement.Innovations in Measurement Techniques”It is typical to examine changes in polymer movies by subjecting them to a treatment, such as irradiating with light, and then making measurements or observations later. However, this offers limited details,” describes study lead author Keishi Yang. “Using an HS-AFM setup consisting of an inverted optical microscopic lense with a laser, enabled us to trigger modifications in azo-polymer films while observing them in real-time with high spatiotemporal resolution.”(a) Overview of the high-speed atomic force microscopy incorporated with the laser irradiation system (b) High-speed atomic force microscopic lense images of the azo-polymer contortion. Credit: The American Chemical SocietyThe HS-AFM measurements had the ability to track the dynamic modifications in the surfaces of the polymer films in motion pictures with two frames per second. It was likewise discovered that the instructions of the polarized light used had an influence on the last surface area pattern.Further investigation using the in situ method is expected to cause a thorough understanding of the mechanism of light-driven azo-polymer deformation, allowing the potential of these materials to be taken full advantage of.”We have demonstrated our method for observing polymer movie contortion,” states research study senior author Takayuki Umakoshi. “However, in doing so, we have revealed the potential of combining tip-scan HS-AFM and a laser source for use across products science and physical chemistry.”Materials and processes that react to light are essential in a wide range of fields in chemistry and biology, including picking up, imaging, and nanomedicine. The in situ strategy supplies an opportunity to deepen understanding and maximize prospective and are thus expected to be applied to various optical devices.Reference: “In Situ Real-Time Observation of Photoinduced Nanoscale Azo-Polymer Motions Using High-Speed Atomic Force Microscopy Combined with an Inverted Optical Microscope” by Keishi Yang, Feng-Yueh Chan, Hiroki Watanabe, Shingo Yoshioka, Yasushi Inouye, Takayuki Uchihashi, Hidekazu Ishitobi, Prabhat Verma and Takayuki Umakoshi, 26 February 2024, Nano Letters.DOI: 10.1021/ acs.nanolett.3 c04877The study was moneyed by the Japan Society for the Promotion of Science and the Ministry of Education, Culture, Sports, Science and Technology.
