Ag nanoparticles immobilized on C:H:N:O plasma polymer film by elevated temperature for LSPR sensing

The dependence of nanoparticles' plasmonic properties on the medium's material surrounding them finds utilization in sensing applications. However, as the detection sensitivity exponentially decreases with distance from the nanoparticles, direct contact between the medium and the nanoparticles is required to obtain the highest signal. This study shows how to prepare such a localized surface plasmon resonance sensor composed of gas-phase synthesized Ag nanoparticles and magnetron sputtered C:H:N:O plasma polymer film. It is proved that excellent stability of Ag/C:H:N:O, enduring even ultrasound bath, may be reached by heating the C:H:N:O film during the deposition of Ag nanoparticles. Such a prepared sensor exhibits a sensitivity of 78 nm/RIU and detects medium changes at distances over 32 nm from its surface.

Automated summary

This study demonstrates the preparation of a localized surface plasmon resonance sensor using Ag nanoparticles and C:H:N:O plasma polymer film, showing excellent stability and high sensitivity. By heating the C:H:N:O film during Ag nanoparticles deposition, the sensor achieves optimal performance, detecting medium changes at distances over 32 nm from its surface.