{'fraction_non_alphanumeric': 0.017899761336515514, 'fraction_numerical': 0.00477326968973747, 'mean_word_length': 4.908450704225352, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Tunable-delay shunts for paper microfluidic devices.

We demonstrate a novel method for controlling fluid flow in paper-based devices. The method delays fluid progress through a porous channel by diverting fluid into an absorbent pad-based shunt placed into contact with the channel. Parameters to control the delay include the length and the thickness of the shunt. Using this method, reproducible delays ranging from 3 to 20 min were achieved. A simple electrical circuit model was presented and used to predict the delays in a system. Results from the model showed good agreement with experimental observations. Finally, the shunts were used for the sequential delivery of fluids to a detection zone in a point-of-care compatible folding card device using biochemical reagents for the amplified detection of the malaria protein PfHRP2.