title: Non-invasive mapping of interstitial fluid pressure in microscale tissues.
abstract: This study describes a non-invasive method for mapping interstitial fluid pressure within hydrogel-based microscale tissues. The method is based on embedding (or forming) a tissue within a silicone (PDMS) microfluidic device, and measuring the extremely slight displacement (<1 μm) of the PDMS optically when the device is pressurized under static and flow conditions. The displacement field under uniform pressure provides a map of the local device stiffness, which can then be used to obtain the non-uniform pressure field under flow conditions. We have validated this method numerically and applied it towards determining the hydraulic properties of tumor cell aggregates, blind-ended epithelial tubes, and perfused endothelial tubes that were all cultured within micropatterned collagen gels. The method provides an accessible tool for generating high-resolution maps of interstitial fluid pressure for studies in mechanobiology.
authors.affiliation: Department of Mechanical Engineering, Boston University, Boston, MA, USA.
authors.forename: Ozgur
authors.initials: O
authors.lastname: Ozsun
authors.forename: Rebecca L
authors.initials: RL
authors.lastname: Thompson
authors.forename: Kamil L
authors.initials: KL
authors.lastname: Ekinci
authors.forename: Joe
authors.initials: J
authors.lastname: Tien
mesh_terms: D000818:Animals; D002417:Cattle; D002460:Cell Line; D003198:Computer Simulation; D004285:Dogs; D045604:Extracellular Fluid / Q000502:physiology*; D020342:Finite Element Analysis; D020100:Hydrogels; D006874:Hydrostatic Pressure; D051379:Mice; D008857:Microscopy, Interference; D008962:Models, Theoretical
chemical_list: D020100:Hydrogels