the disclosure relates to methods and devices for measuring samples , such as biological samples , especially those at low abundance , with high sensitivity and at low cost . a sample is disposed on a shrinkable scaffold and the shrinkable scaffold is shrunk , reducing the area where the sample is distributed , so as to effectively concentrate the sample on the surface of the scaffold . in the event that a biological sample is covalently attached to a scaffold having a silica structure , the increase in signal enhancement is also due to optical effects stemming from covalent linkage of the biological sample onto the silica structure of the scaffold . silica may be deposited onto a surface of a polymer film by functionalizing the surface of the polymer film to bind silica from a sol - gel solution , and coating the film with a sol - gel solution containing silica precursors , wherein solid silica from the sol - gel solution is deposited onto the surface of the polymer film . also disclosed is an immunoassay platform comprising a silica - encapsulated first detection agent deposited on a polymer substrate .