TY - JOUR T1 - Hybridization-based DNA biosensing with a limit of detection of 4 fM in 30 s using an electrohydrodynamic concentration module fabricated by grayscale lithography A1 - Tijunelyte,Inga A1 - Teillet,Jeffrey A1 - Bruand,Paul A1 - Courson,Remi A1 - Lecestre,Aurélie A1 - Joseph,Pierre A1 - Bancaud,Aurélien AD - CNRS, LAAS, 7 avenue du colonel Roche, F-31400 Toulouse, France UR - https://archimer.ifremer.fr/doc/00791/90254/ DO - 10.1063/5.0073542 N2 - Speeding up and enhancing the performances of nucleic acid biosensing technologies have remained drivers for innovation. Here, we optimize a fluorimetry-based technology for DNA detection based on the concentration of linear targets paired with probes. The concentration module consists of a microfluidic channel with the shape of a funnel in which we monitor a viscoelastic flow and a counter-electrophoretic force. We report that the technology performs better with a target longer than 100 nucleotides (nt) and a probe shorter than 30 nt. We also prove that the control of the funnel geometry in 2.5D using grayscale lithography enhances sensitivity by 100-fold in comparison to chips obtained by conventional photolithography. With these optimized settings, we demonstrate a limit of detection of 4 fM in 30 s and a detection range of more than five decades. This technology hence provides an excellent balance between sensitivity and time to result. Y1 - 2022/07 PB - AIP Publishing JF - Biomicrofluidics SN - 1932-1058 VL - 16 IS - 4 ID - 90254 ER -