High-throughput biointerfaces for direct, label-free, and multiplexed metaplasmonic biosensing

In recent years, metaplasmonic biosensors have emerged as a novel counterpart of well-established plasmonic biosensors based on thin metallic layers. Metaplasmonic biosensors offer high potential for sensor miniaturization, extreme sensitivity biosensing, and high multiplexing capabilities with detection methods free of coupling optical elements. These capabilities make metaplasmonic biosensors highly attractive for Point-of-Care and handled/portable devices or novel On-Chip devices; as a result, it has increased the number of prototypes and potential applications that emerged during the last years. One of the main challenges to achieving fully operative devices is the achievement of high-throughput biointerfaces for sensitive and selective biodetection in complex media. Despite the superior surface sensitivity achieved by metaplasmonic sensors compared to conventional plasmonic sensors based on metallic thin films, the main limitations to achieving high-throughput and multiplexed biosensing usually are associated with the sensitivity and selectivity of the biointerface and, as a consequence, their application to the direct analysis of real complex samples. This graphical review discusses the potential challenges and capabilities of different biofunctionalization strategies, biorecognition elements, and antifouling strategies to achieve scalable and high-throughput metaplasmonic biosensing for Point-of-Care devices and bioengineering applications like Organs-On-Chip.