A review of passive and active mixing systems in microfluidic devices

James Green, Arne Holdø, Aman Khan


A review of mixing elements and devices for microscale fluidic devices is presented. The application, principles and characterisation of these devices is discussed, and the classifications based on these factors highlighted. A review of published works relating both experimental and simulation profiling of both passive and active mixing systems is presented. Each mixing principle upon which a design is based is discussed with regard to the fundamental physics that governs fluid behaviour. Passive systems covered include multi-lamination, split/recombination, chaotic advection, jet based, recirculation and droplet internal convection. Active systems covered include longitudinal and transverse pulsing, micro-stirrers, electro-kinetic methods, and acoustic/ultrasonic excitation. The review shows that the majority of devices have been designed within the past five years. Furthermore, at present, devices based on the multi-laminate method appear to outperform most other systems. 

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DOI: http://dx.doi.org/10.1260/175095407780130544

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