Integrated Microneedle Aptasensing Platform toward Point-of-Care Monitoring of Bacterial Infections and Treatment

Point-of-care (POC) monitoring of clinical inflammation biomarkers in interstitial fluid (ISF) has a great perspective on personalized healthcare. Herein, an integrated ultraswelling microneedle aptamer-recognition tester (uSMART) was developed for POC monitoring of antibiotic-resistant bacterial infections and therapeutic outcomes. The hyaluronic acid methacryloyl/sodium hyaluronate-microneedle (HAMA/SH-MN) module with excellent swelling and mechanical properties could cross the epidermis and access enough dermis ISF in a minimally invasive, painless, and rapid manner. Meanwhile, the hierarchical flower-like gold nanostructure-decorated screen-printed carbon electrode (HFGN-SPCE) combined with a target-induced aptamer-recognition unit was employed as the reagentless nanosensing module to sensitively and selectively detect C-reactive protein (CRP). <i>In vitro</i> electrochemical analysis and simulation testings demonstrate that the integrated uSMART has high performance in CRP detection, including a wide linear range, a low limit of detection, outstanding selectivity, superior repeatability, and long-term stability. Importantly, the uSMART system enables continuous monitoring of CRP throughout the methicillin-resistant <i>Staphylococcus aureus</i> (MRSA)-infected and vancomycin (VA)-treated cycle <i>in vivo</i>. Moreover, the strong correlation between CRP levels in ISF and blood suggests that our uSMART offers a potential alternative to traditional invasive and labor-intensive testings.