title: Doppler optical coherence tomography imaging of local fluid flow and shear stress within microporous scaffolds.
abstract: Establishing a relationship between perfusion rate and fluid shear stress in a 3D cell culture environment is an ongoing and challenging task faced by tissue engineers. We explore Doppler optical coherence tomography (DOCT) as a potential imaging tool for in situ monitoring of local fluid flow profiles inside porous chitosan scaffolds. From the measured fluid flow profiles, the fluid shear stresses are evaluated. We examine the localized fluid flow and shear stress within low- and high-porosity chitosan scaffolds, which are subjected to a constant input flow rate of 0.5 ml min(-1). The DOCT results show that the behavior of the fluid flow and shear stress in micropores is strongly dependent on the micropore interconnectivity, porosity, and size of pores within the scaffold. For low-porosity and high-porosity chitosan scaffolds examined, the measured local fluid flow and shear stress varied from micropore to micropore, with a mean shear stress of 0.49+/-0.3 dyn cm(-2) and 0.38+/-0.2 dyn cm(-2), respectively. In addition, we show that the scaffold's porosity and interconnectivity can be quantified by combining analyses of the 3D structural and flow images obtained from DOCT.
authors: Oregon Health and Science University, Department of Biomedical Engineering, 3303 South West Bond Avenue, Portland, Oregon 97239, USA.
authors: Yali
authors: Y
authors: Jia
authors: Pierre O
authors: PO
authors: Bagnaninchi
authors: Ying
authors: Y
authors: Yang
authors: Alicia El
authors: AE
authors: Haj
authors: Monica T
authors: MT
authors: Hinds
authors: Sean J
authors: SJ
authors: Kirkpatrick
authors: Ruikang K
authors: RK
authors: Wang
mesh_terms: D048271:Chitosan / Q000737:chemistry; D004301:Doppler Effect; D004867:Equipment Design; D044085:Microfluidics / Q000379:methods; D019047:Phantoms, Imaging; D016062:Porosity; D033081:Shear Strength; D013314:Stress, Mechanical; D023822:Tissue Engineering; D054457:Tissue Scaffolds / Q000737:chemistry*; D041623:Tomography, Optical Coherence / Q000295:instrumentation / Q000379:methods*
chemical_list: D048271:Chitosan