Advancements in BioAFM: Fluid Micro Cantilevers and Novel Thermocouple Devices for Cellular Analysis

A. Gaitas
Icahn School of Medicine at Mt. Sinai,
United States

Summary:

This talk will cover developments in bioAFM innovations in my laboratory. First, we utilize fluid micro cantilevers in atomic force microscopy (AFM) for a range of applications, including the precise measurement of single-cell mass in a media environment. This advanced technique allows for a detailed analysis of the nano-mechanical properties of human induced pluripotent stem cells (iPSCs) and their differentiation into cardiomyocytes (iPSC-CMs). The employment of fluid micro cantilevers in AFM enhances the accuracy and scope of our measurements, revealing significant changes in cell elasticity and mass during iPSC differentiation. These findings establish elasticity and mass as key indicators in evaluating the development of iPSCs, providing invaluable insights for cell therapy, drug testing, and cardiac disease research. Our study demonstrates the capability of AFM, especially with the use of fluid micro cantilevers, to effectively differentiate cells pre- and post-differentiation based on their mechanical properties. This advancement underscores the potential of these techniques as morphological markers in iPSC research. The results, while promising, necessitate further studies to confirm their generalizability to other cell lines. Additionally, our work points to the necessity of developing more refined AFM measurement techniques in fluid media, proposing various methods to enhance the technology's resolution and accuracy in future research applications. Second, we have developed a novel thermocouple device tailored for intracellular temperature measurement. Temperature regulation and gradients are crucial in biological research, as thermal events significantly impact cellular functions. This microcantilever thermocouple sensor combines doped silicon and gold to form a sensitive junction, suitable for biological applications. Its design ensures mechanical robustness, high sensitivity, and rapid response, ideal for liquid environments and minimal impact on cellular processes. The fabrication involves several precise steps, resulting in a sensor with a high Seebeck coefficient (447 μV/°C) and millisecond response time. This advanced device has demonstrated effective and precise transient thermometry in biological samples, showing its potential in understanding and measuring thermal events at a cellular level.