Automated Methods to Determine Electrospun Fiber Alignment and Diameter Using the Radon Transform

Abstract

Recent evidence demonstrates the ability to change cell function by altering the physical properties of electrospun scaffolds, but many studies still do not characterize electrospun fiber alignment and diameter. To aid in the reporting of these crucial properties, we demonstrate two methods of quantifying electrospun fiber alignment with one method capable of determining electrospun fiber diameter. The first method assesses fiber alignment in a scanning electron microscopy image using the Radon Transform (RT) to calculate the entropy of the fibers in the image. The RT entropy method was more sensitive than a commonly used Fast Fourier Transform (FFT) method because the RT method was able to assess smaller changes in alignment (±2°) than the FFT (±4°, p ± 8°). The RT is introduced as a sensitive tool for assessing electrospun fiber alignment, but more importantly, we have demonstrated for the first time an automated method of determining electrospun fiber diameter.