Nanoplasmonic biosensors based on gold nanoparticle functionalized smooth silica and porous calcium carbonate particles are presented. It is identified in this comparative study the role of porosity for adsorbing gold nanoparticles and subsequent detection of biomarkers. That is further applied in this study for detection of biomarkers. Detection of glucose – a biomarker of diabetes is studied together with that of bovine serum albumin – a very relevant bio-molecule. Raman scattering is used for label-free detection of molecules in the sub-µM–mM range detection capabilities, which covers the range corresponding to healthy and diseased persons. Implications of current study for detection and identification of biomarkers are discussed.