Chemical nanosensors with a submicrometer core-shell composite design, based on a polymer core, a molecularly imprinted polymer (MIP) shell for specific analyte recognition, and an interlayer of gold nanoparticles for signal amplification, are described. SERS measurements on single nanosensors yield detection limits of 10(-7) M for the beta-blocker propranolol, several orders of magnitude lower than on plain MIP spheres.