Soft Polymer-Based Technique for Cellular Force Sensing

Abstract

Soft polymers have emerged as a vital type of material adopted in biomedical engineering to perform various biomechanical characterisations such as sensing cellular forces. Distinct advantages of these materials used in cellular force sensing include maintaining normal functions of cells, resembling in vivo mechanical characteristics, and adapting to the customised functionality demanded in individual applications. A wide range of techniques has been developed with various designs and fabrication processes for the desired soft polymeric structures, as well as measurement methodologies in sensing cellular forces. This review highlights the merits and demerits of these soft polymer-based techniques for measuring cellular contraction force with emphasis on their quantitativeness and cell-friendliness. Moreover, how the viscoelastic properties of soft polymers influence the force measurement is addressed. More importantly, the future trends and advancements of soft polymer-based techniques, such as new designs and fabrication processes for cellular force sensing, are also addressed in this review.

Biodegradable Carrageenan-Based Force Sensor: An Experimental Approach

“…It is worth noting that the research and development of biodegradable force sensors is ongoing, and advancements in materials science and sensor technology continue to improve their performance, sensitivity, and degradation properties. Reviewing the most exciting solutions for biodegradable polymer-based force sensors, the work of Yu et al [17] is worth mentioning. Researchers have developed biodegradable force sensors using polymer-based materials, such as polylactic acid (PLA) or polyhydroxyalkanoates (PHA).…”

Quantification of cell contractile behavior based on non-destructive macroscopic measurement of tension forces on bioprinted hydrogel

“…During cultivation of 3D in vitro models, cells generate tractional forces. When they are seeded on compliant materials such as collagen hydrogels, such forces reshape the structures surrounding the cells [22,23]. This results in changes of hydrogels volume, mostly along the radial direction [24], which is known as matrix contraction [22].…”

“…Bell and co-workers introduced collagen contraction assays to evaluate fibroblasts behavior in collagen hydrogels [25]. This macroscopic method has been widely applied as it requires only images of hydrogels or scaffolds to monitor surface area [4,23,24,26,29,39,40]. It has the benefit to be non-destructive and supports longitudinal monitoring.…”

“…Although they provide quantitative data on forces generated by individual cells, these techniques are limited to 2D cultures and failed to be transferred to 3D environment to mimic in vivo traction forces. Traction force microscopy has been adapted to 3D cell culture system [44] but it is mostly used with purely elastic materials that do not reproduce the biochemical and mechanical properties of ECM [23,24]. Another major drawback is the inherent evolutive behavior of cells.…”

Force Estimation during Cell Migration Using Mathematical Modelling

“…A mechanic-optical biosensor is described in [ 22 ] to sense local cell adhesive forces. In [ 10 ] the authors discuss about membrane fluctuations and [ 23 ] summarises soft polymers that are typically used to measure cellular forces.…”