Buckling-Based Method for Evaluating Young's Modulus of Microfiber and Predicting Cell Growth

Variety of microfibers have been widely utilized as a promising bioink for 3D bioprinting. However, the mechanical properties of the cell-laden microfiber are difficult to be characterized precisely due to the lack of low-damage loading methods for encapsulated cells that require a relatively short loading time. In this paper, we propose a bulking-based method for rapidly evaluating the Young's modulus, Ec of the microfibers within several seconds. A two-probe based micromanipulation system is utilized to compress the microfiber. Based on the computer vision, the compression force is measured and used for calculating the Ec according to the Euler column formula, and it is found that the evaluation results of Ec can be improved in a high compression speed. Moreover, the precision of measure Ec is guaranteed and the value is close to the other loading methods. The results show the proposed method can realize a high precise measurement in about 2s which is faster than other methods. Additionally, the measured Ec is used to predict the cell growth of cell-laden microfibers in the next few days, demonstrating its potential for speeding up the screening of biocompatible materials.