Fig. 1. A) Sliced computer-aided design scheme of a CellDrum with membrane and cell culture medium. The CellDrum offers a 2cm² cultivation area, consisting of an ultra-flexible polydimethylsiloxane (PDMS) membrane. Due to surface functionalization, cells can attach to the membrane. B) Key Fig. for the CellDrum physical model with CellDrum fitted Barlow´s formula to derive the cellular tension from recorded pressure deflection curves. r) Radius of the CellDrum (16mm). h) Indicates the deflection of the CellDrum membrane to the baseline (in µm). R) Radius of the theoretical hemisphere. The formula is used to derive the tension from the recorded pressure deflection curves. σ) Calculated axial stress (N/m²). p) measured pressure (in Pa). s) CellDrum membrane thickness (in µm). C) Picture of the Tissue Tension Analyzer with detailed schematic arrangement of the measurement socket - 1) CellDrum; 2) Cells attached to the CellDrum membrane with cell culture medium (500µl) on top; 3) Ground electrode; 4) Counter electrode; 5) Electrical shielding; 6) Measurement socket; 7) Deflection sensor; 8) Pressure sensor; 9) Syringe pump; 10) Processing unit; 11) Peripheral computer and data storage.