Abstract: An analyzing system comprises a multi-well sample carrier in which each well has a transparent bottom with a nanostructured surface inside the well. The sample carrier can be installed in a reader device so that each well of the sample carrier is aligned with a respective light guiding unit of the reader device. In use, each light guiding unit directs a beam of excitation light to the bottom of the respective well, and directs a beam of reflected light from the bottom of the respective well. The nanostructured surface acts as a plasmonic sensor to facilitate analysis of the contents of the wells. The system allows highly sensitive quantification and characterisation of biological interactions in real time across multiple wells, and with improvements in yields, quality and production times.