Membrane type comparison and modification to modulate sample flow in paper diagnostics

Common membrane types were compared and modified to modulate sample flow in paper-based diagnostics. The modulation of sample flow may potentially increase the sensor performance by demonstrating higher detection sensitivity and specificity. Five different membranes were compared: glassfiber, polyester, nitrocellulose, polyvinylidene-difluoride and cellulose. The finalized modified setup (862 RLU) demonstrated a higher detection sensitivity vs. the initial setup (290 RLU). Moreover, the positive/negative detection ratio was higher in the modified setup (3.10) vs. the initial setup (1.80). The selection of membrane types and their modifications can modulate sample flow and increase the sensitivity of detection in paper diagnostics. [Display omitted] •Sample flow modulation in paper diagnostics increase exposure between immunoreagents that may increase sensor performance.•Selection of membrane types and their modifications modulate sample flow and may increase the sensitivity of detection.•Five different membranes were compared: glassfiber, polyester, nitrocellulose, polyvinylidene-difluoride and cellulose.•Polyester membrane as separation layer and skim-milk tween-based buffer promotes antibody release and flow in the sensor.•Control of membranes type and their modifications inside paper-based sensor increased sensing sensitivity and performance. Paper-based diagnostics are rapid, robust, affordable and user-friendly, thus have potential for point-of-care. Modulation of sample flow in these technologies have the advantage of increased exposure between immunoreagents, which ensures higher sensitivity and specificity. In this study, common membrane types were compared and modified to modulate sample flow. Five different membranes were compared: glassfiber, polyester, nitrocellulose, polyvinylidene-difluoride and cellulose. Several parameters were tested for their effect on the sample flow: membranes absorption capacity, immobilization of buffer solution, different membrane types as separation layer and sample volume. The effect of separation membrane on the sample flow was tested using a ‘Stack-Pad’ sensor layout. Higher antibody levels could reach the three absorption pads, with the use of polyester separation membrane (340, 440 and 408 RLU), as compared to the glassfiber separation membrane (208, 198 and 107 RLU), thus potentially increasing the sensor sensitivity. Lastly, the effect of the membrane type and its modifications on the detection sensitivity wa