Engineering a Point-of-Care Paper-Microfluidic Electrochemical Device Applied to the Multiplexed Quantitative Detection of Biomarkers in Sputum

Health initiatives worldwide demand affordable point-of-caredevicesto aid in the reduction of morbidity and mortality rates of high-incidenceinfectious and noncommunicable diseases. However, the production ofrobust and reliable easy-to-use diagnostic platforms showing the abilityto quantitatively measure several biomarkers in physiological fluidsand that could in turn be decentralized to reach any relevant environmentremains a challenge. Here, we show the particular combination of paper-microfluidictechnology, electrochemical transduction, and magnetic nanoparticle-basedimmunoassay approaches to produce a unique, compact, and easily deployablemultiplex device to simultaneously measure interleukin-8, tumor necrosisfactor-& alpha;, and myeloperoxidase biomarkers in sputum, developedwith the aim of facilitating the timely detection of acute exacerbationsof chronic obstructive pulmonary disease. The device incorporatesan on-chip electrochemical cell array and a multichannel paper component,engineered to be easily aligned into a polymeric cartridge and exchangedif necessary. Calibration curves at clinically relevant biomarkerconcentration ranges are produced in buffer and artificial sputum.The analysis of sputum samples of healthy individuals and acutelyexacerbated patients produces statistically significant biomarkerconcentration differences between the two studied groups. The devicecan be mass-produced at a low cost, being an easily adaptable platformfor measuring other disease-related target biomarkers.