Image analysis method for measurement and prediction of intra-matrix IgG diffusion

Measurement and imaging of intra-matrix protein therapeutics diffusion is important due to the emergence of injectable biologics currently in various stages of research and clinical testing. These therapeutics are developed for delivery to hyaluronic acid (HA)-rich anatomical sites such as subcutaneous tissue, the vitreous humor, and knee joints, depending on the target tissue. Understanding their diffusion behavior is essential for optimizing drug delivery strategies. Our work presents an image analysis method suited for tracking IgG diffusion in low viscosity HA matrices representative of the vitreous humor, where diffusion occurs more rapidly unlike a previously reported analysis method for higher viscosity matrices where protein diffusion is significantly slower. The current method utilizes scanner images at 6.3 MP resolution, and an algorithm that removes background and calculates protein mass and concentration measured directly within matrices formulated to represent HA in an intravitreal environment. We report and demonstrate a robust method for predicting protein diffusion coefficient from images of label-free protein diffusing in a low viscosity HA matrix.