Surface-enhanced Molecular adsorbed on rough metal surfaces enhance Raman scattering via Raman scattering (SERS), a surface-sensitive method. 107 -1015 is the maximum enhancement factor possible, making this method sensitive enough to detect single molecules. The use of SERS-tags has evolved into clinical diagnostics; the enhancement of the intrinsic signal of biomolecules on SERS active materials shows tremendous promise for the analysis of biomolecules and potential biomedical assays. To date, the detection of the de novo signal has been reported for a wide variety of biomolecules. Various classes of biomolecules are examined in this review for the signals they have been observed and the experimental details that enable their detection. We have found.