Rheological tunability of fibers networks with embedded magnetic particles

Magnetic nano-particles have gained popularity for in vivo applications due to their rapid, reversible, and non-invasive nature, with potential application in surgical procedures for tuning tissue stiffness and remotely controlling drug delivery. However, the effects of magnetic particles on the mechanics of collagenous tissues has not been thoroughly explored. Experimental difficulties arise from stress response measurement precision, contrasting agents' noise, the spatial dispersion of magnetic particles and dynamic measurement of rheological quantities. To address this, we present a minimalistic numerical model to study the effects of external magnetic fields on the mechanical response of nonlinear fiber networks with embedded magnetic particles. In our model, we assume that the particles are superparamagnetic and embedded into sub-isostatic fiber networks that represent collagenous tissues. Our preliminary findings suggest that the network undergoes a phase transition-like state under applied magnetic fields at zero shear. We also observe an increase in shear modulus and earlier phase transitions as we increase the magnetic particles concentration. Speculating that these observations are caused by the coupling of non-affine rearrangement and the magnetic interactions between the particles, our model is expected to provide valuable insights into the underlying mechanisms involved in tuning the mechanical properties of tissues with magnetic particles.