Implantable Sensors for Regenerative Medicine

Abstract

The translation of many tissue engineering/regenerative medicine (TE/RM) therapies that demonstrate promise in vitro are delayed or abandoned due to reduced and inconsistent efficacy when implemented in more complex and clinically relevant preclinical in vivo models. Determining mechanistic reasons for impaired treatment efficacy is challenging after a regenerative therapy is implanted due to technical limitations in longitudinally measuring the progression of key environmental cues in vivo. The ability to acquire real-time measurements of environmental parameters of interest including strain, pressure, pH, temperature, oxygen tension, and specific biomarkers within the regenerative niche in situ would significantly enhance the information available to tissue engineers to monitor and evaluate mechanisms of functional healing or lack thereof. Continued advancements in material and fabrication technologies utilized by microelectromechanical systems (MEMSs) and the unique physical characteristics of passive magnetoelastic sensor platforms have created an opportunity to implant small, flexible, low-power sensors into preclinical in vivo models, and quantitatively measure environmental cues throughout healing. In this perspective article, we discuss the need for longitudinal measurements in TE/RM research, technical progress in MEMS and magnetoelastic approaches to implantable sensors, the potential application of implantable sensors to benefit preclinical TE/RM research, and the future directions of collaborative efforts at the intersection of these two important fields.

Real-time monitoring of mechanical cues in the regenerative niche reveal dynamic strain magnitudes that enhance bone repair

“…A promising approach to quantitatively evaluate mechanical cues during tissue repair is the integration of electromechanical sensors with devices already typically installed at the site of healing, such as fixation plates, implants, or scaffolds ( 18 ). Advancements in microfabrication and wireless data transfer have attained a level of maturity and a sufficiently small size for biomedical applications.…”

The Shape and Function of Solid Fascias Depend on the Presence of Liquid Fascias

“…It can be placed in contact with body fluids containing glucose, under the skin or in the backbone. Batteries operate using biological fluids [15]. Body fluids emit light, in particular, the blood emits biophotons or ultra-weak photon emission (UPE) [16].…”

Building better bone: The weaving of biologic and engineering strategies for managing bone loss

“…Optimization of the mechanical environment is critical for bone homeostasis, with strategies like DO as described above currently in use clinically. Recent studies have investigated the control and measurement of the mechanical loading environment in bone tissue engineering . The environment needs to balance loading and the material properties of the graft, and the graft itself does not necessarily need to support loads .…”

“…The timing of loading in the healing cascade and the individualized graft effects need to be more rigorously evaluated prior to translational consideration. To do this, wireless miniaturized microelectromechanical systems (MEMS) sensors can be incorporated into graft materials to measure loading cues throughout the healing process . A better engineering understanding of the mechanical requirements of individualized grafts and the ability to detect real‐time environmental mechanical cues has the capacity to direct real‐time important clinical decision‐making (i.e., when can you weight bear?…”