title: In vitro colocalization of plasmonic nano-biolabels and biomolecules using plasmonic and Raman scattering microspectroscopy.
abstract: An insight into the intracellular fate of theranostics is important for improving their potential in biological applications. In vivo efficacy of plasmonic theranostics depends on our ability to monitor temporal changes in their size, shape, and state of aggregation, and the identification of molecules adsorbed on their surfaces. We develop a technique which combines plasmonic and Raman scattering microspectroscopy to colocalize plasmonic scattering from metallic nanoparticles with the Raman signatures of biomolecules adsorbed on the surface of the former. Using this technique, we have colocalized biomolecules with the plasmonic scattering from silver nanoparticles in the vicinity of Escherichia coli bacteria. To prove the applicability of this setup for the measurements on mammalian cells, imaging of HEK293 cells treated with gold nanoparticles was performed. We discuss the importance of such correlated measurements over individual techniques, although the latter may lead to misinterpretation of results. Finally, with the above-mentioned examples, we have given criteria to improve the specificity of theranostics. We believe that this methodology will be considered as a prime development in the assessment of theranostics.
authors.forename: Kamalesh
authors.initials: K
authors.lastname: Chaudhari
authors.forename: Thalappil
authors.initials: T
authors.lastname: Pradeep
mesh_terms: D004926:Escherichia coli / Q000737:chemistry* / Q000648:ultrastructure; D006046:Gold / Q000737:chemistry*; D057809:HEK293 Cells; D006801:Humans; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D057054:Molecular Imaging / Q000379:methods; D010316:Particle Size; D013059:Spectrum Analysis, Raman / Q000379:methods*; D013194:Staining and Labeling; D013347:Subcellular Fractions / Q000737:chemistry* / Q000648:ultrastructure; D020349:Surface Plasmon Resonance / Q000379:methods*; D014018:Tissue Distribution
chemical_list: D006046:Gold