Barrier-film-based reagent storage and release on microfluidic platforms for sample-to-answer automation of bioassays

We present the manufacture, assembly and characterization of a novel, low-cost and scalable technology for aqueous reagent storage and release, based on sacrificial barrier films. We demonstrate an average evaporative volume loss of stored DI water at room temperature (21oC) of 0.38% (± 0.3) for 42 days at a significantly low materials cost of 30 cents per film unit. We also demonstrate a reliable centrifugal reagent-release mechanism within a band of ±1.40 Hz for varying radial positions and release frequencies with post-release cumulative reagent losses of 2.5μl (± 1.3μl). Other release mechanisms such as manual application of the release liquid for capillary release or physical breakage of the film insert using passive external pins are also feasible.