title: Label-free detection of proteins from dried-suspended droplets using surface enhanced Raman scattering.
abstract: A simple sample preparation method to obtain rich and reproducible surface-enhanced Raman scattering (SERS) spectra from proteins regardless of their surface properties and dimensions for label-free detection and identification is reported. The method uses colloidal silver nanoparticles (AgNPs) as substrates and is based on suspending the droplet of a mixture containing AgNPs and proteins from a hydrophobic surface. Drying the droplet at this suspended configuration allows the accumulation and packing of AgNPs and protein molecules in the middle of the droplet area rather than getting jammed at the edges of drying droplets as the solvent evaporates. A detection limit of down to 0.05 μg mL(-1) for some of the model proteins used in this study is obtained with this simple approach. The advantage of this method is its simplicity and improved sensitivity over other approaches reported in the literature.
authors.affiliation: Department of Genetics and Bioengineering, Faculty of Engineering, Yeditepe University, Atasehir, Istanbul, Turkey.
authors.forename: Sercan
authors.initials: S
authors.lastname: Keskin
authors.forename: Mustafa
authors.initials: M
authors.lastname: Culha
mesh_terms: D057927:Hydrophobic and Hydrophilic Interactions; D053768:Metal Nanoparticles / Q000737:chemistry / Q000648:ultrastructure; D011506:Proteins / Q000032:analysis*; D012834:Silver / Q000737:chemistry; D013059:Spectrum Analysis, Raman; D013499:Surface Properties
chemical_list: D011506:Proteins; D012834:Silver