Recent advances on open fluidic systems for biomedical applications: A review

authors	Oliveira, NM; Vilabril, S; Oliveira, MB; Reis, RL; Mano, JF
nationality	International
journal	MATERIALS SCIENCE & ENGINEERING C-MATERIALS FOR BIOLOGICAL APPLICATIONS
author keywords	Microfluidics; Open fluidics; Superhydrophobicity; Superhydrophilicity; Fluid confinement; Lab on a chip
keywords	SUPERHYDROPHOBIC-PATTERNED SURFACE; SPONTANEOUS CAPILLARY-FLOW; ON-A-CHIP; RECENT PROGRESS; DRIVEN FLOW; MICROFLUIDIC TRANSPORT; BIOINSPIRED SURFACES; STRUCTURED SURFACES; ANALYTICAL DEVICES; DROPLET-ARRAY
abstract	Microfluidics has become an important tool to engineer microenvironments with high precision, comprising devices and methods for controlling and manipulating fluids at the submillimeter scale. A specific branch of microfluidics comprises open fluidic systems, which is mainly characterized by displaying a higher air/liquid interface when compared with traditional closed-channel setups. The use of open channel systems has enabled the design of singular architectures in devices that are simple to fabricate and to clean. Enhanced functionality and accessibility for liquid handling are additional advantages inputted to technologies based on open fluidics. While benchmarked against closed fluidics approaches, the use of directly accessible channels decreases the risk of clogging and bubble-driven flow perturbation. In this review, we discuss the advantages of open fluidics systems when compared to their closed fluidics counterparts. Platforms are analyzed in two separated groups based on different confinement principles: wall-based physical confinement and wettability-contrast confinement. The physical confinement group comprises both open and traditional microfluidics; examples based on open channels with rectangular and triangular cross-section, suspended microfluidics, and the use of narrow edge of a solid surface for fluid confinement are addressed. The second group covers (super)hydrophilic/(super) hydrophobic patterned surfaces, and examples based on polymer-, textile- and paper-based microfluidic devices are explored. The technologies described in this review are critically discussed concerning devices' performance and versatility, manufacturing techniques and fluid transport/manipulation methods. A gather-up of recent biomedical applications of open fluidics devices is also presented.
publisher	ELSEVIER
issn	0928-4931
isbn	1873-0191
year published	2019
volume	97
beginning page	851
ending page	863
digital object identifier (doi)	10.1016/j.msec.2018.12.040
web of science category	Materials Science, Biomaterials
subject category	Materials Science
unique article identifier	WOS:000457952800085