Abstract: A biosensor includes a microstrip resonator, a collection actuator disposed adjacent to and spaced from the microstrip resonator, a port unit connected to a network analyzer and coupled with the microstrip resonator, and a substrate. The microstrip resonator includes a collecting portion provided with an analyte-specific reagent (ASR) for binding an analyte in a suspension. The collection actuator and the microstrip resonator are applied with alternating current (AC) electric energy to induce AC electrokinetic stirring in the suspension for actuating the binding. The microstrip resonator resonates at a resonant frequency associated with the binding so that the analyte can be quantified.

Abstract: A microstrip antenna structure is provided, which includes a substrate, a ring microstrip line and a signal transmission port. The substrate has opposite first and second surfaces. The ring microstrip line is disposed on the first surface of the substrate. The ring microstrip line has a short coupling gap ranged between 0.004?g and 0.06?g for forming a radiation bandwidth with high selectivity, where ?g represents a guided wavelength of an electromagnetic wave in the ring microstrip line corresponding to a center frequency of the radiation bandwidth. The signal transmission port is disposed on the second surface of the substrate. The signal transmission port penetrates through the substrate and is electrically connected to the ring microstrip line.