Femtosecond-laser-structured nitrocellulose membranes for multi-parameter Point-of-Care tests

Cheap and disposable Point-of-Care diagnostic devices are of great interest to combat the rising cost of healthcare in industrial nations but also for a widespread use in the developing world. Paper based microfluidic devices as well as well-established lateral flow tests (LFTs) are both well suited for this role. However, they share various disadvantages including restricted reproducibility for quantitative readouts and are in most cases limited to a single parameter per test. In order to address these drawbacks we present a novel laser fabrication method for multi-parametric lateral flow tests based on nitrocellulose membranes. Using a femtosecond laser the membrane can be structured into barriers and channels which separate and guide the test liquid. By varying the laser parameters the presented method allows the rapid area-selective ablation of the entire membrane-thickness to the polyester backing thus creating a barrier for the fluid transport as well as a much finer, but slower, removal of the membrane material which leaves the membranes pore structure and fluid transport characteristics intact. With barrier and channel widths of 100µm and 300-600µm this process enables the integration of complex multi-parametric detection fluidic networks in the footprint of commercially available LFTs. Display Omitted A novel fabrication method for cheap point of care-tests is presented.Laser-ablated hydrophobic barriers guide test liquid in nitrocellulose membranes.Ablation of nitrocellulose membranes with fs-Laser pulses.Integration of complex multiparametric detection in a small device footprint.