Figure 1.

Examples of research-built and—inspired commercial inplane stretch systems that can be suitable for studies of cardiac cells and mechano-electric feedback. (A) The IsoStretcher device, first described in Schürmann et al. (2016) that uses a V-belt driven, swivel motor actuated rotational-to-radial translation for displacement of six hook-sliders to stretch a PDMS-cast biochamber. Maximum radial stretch of the system is ~20%. An improved current version (2018) is shown. (B) Radial displacement PDMS chamber lip clamp system introduced by Rapalo et al. (2015) to combine isotropic stretch of cells in large culture dishes (about 4 cm diameter) for confocal of atomic force microscopy. Maximum linear strain was 20%. Taken with permission from Rapalo et al. (2015). (C) An iris-like actuated system that uses eight PDMS substrate (HERS: high-extension silicon rubber) holding arms that are screwed to an outer frame allowing rotational degree of freedom of movement while the inner substrate pillar will be pulled toward the outer frame once the outer ring is actuated. For details see Quinn and Majd (2010). Isotropic surface expansions up to 1,000% have been described (Majd et al., 2009). The system was commercialized as Cellerator by the Swiss company Cytomec until 2017. (Adapted from Majd et al., 2009).