title: Nanoplasmonic chitosan nanofibers as effective SERS substrate for detection of small molecules.
abstract: The use of surface enhanced Raman spectroscopy (SERS) is limited by low reproducibility and uniformity of the response. Solving these problems can turn the laboratory use of SERS into real-world application. In this regard, soft SERS-active substrates can enable portable instrumentation and reduce costs in the fabrication of SERS-based sensors. Here, plasmonic free-standing films made of biocompatible chitosan nanofibers and gold nanoparticles are engineered by a simple protocol varying the concentration of chloroauric acid. The concentration and distribution of gold nanoparticles in films are controlled in a predictable way, and SERS spectra for the standard 2-naphthalenethiol with concentration less than 10(-15) M are acquired in a reproducible way. The statistical analysis reveals a relatively high and locally uniform performance of SERS with an enhancement factor of 2 × 10(5) for 86% of the points on the imaged area of the SERS substrate. Potential SERS detection of small molecules, both Rhodamine 6G and d-Glucose, in the micromolar range is demonstrated.
authors.affiliation: †Remote Controlled Theranostic Systems Lab, Institute of Nanostructures and Biosystem, Saratov State University, Saratov, 410012 Russia.
authors.forename: Alexandra N
authors.initials: AN
authors.lastname: Severyukhina
authors.affiliation: †Remote Controlled Theranostic Systems Lab, Institute of Nanostructures and Biosystem, Saratov State University, Saratov, 410012 Russia.|‡A.V. Shubnikov Institute of Crystallography RAS, Moscow, 119333 Russia.
authors.forename: Bogdan V
authors.initials: BV
authors.lastname: Parakhonskiy
authors.affiliation: †Remote Controlled Theranostic Systems Lab, Institute of Nanostructures and Biosystem, Saratov State University, Saratov, 410012 Russia.
authors.forename: Ekaterina S
authors.initials: ES
authors.lastname: Prikhozhdenko
authors.affiliation: †Remote Controlled Theranostic Systems Lab, Institute of Nanostructures and Biosystem, Saratov State University, Saratov, 410012 Russia.
authors.forename: Dmitry A
authors.initials: DA
authors.lastname: Gorin
authors.affiliation: §School of Engineering and Materials Science, Queen Mary University of London, Mile End Road, London, E1 4NS, U.K.
authors.forename: Gleb B
authors.initials: GB
authors.lastname: Sukhorukov
authors.affiliation: ∥Max-Planck Institute for Colloids and Interfaces, Potsdam, 14424 Germany.
authors.forename: Helmuth
authors.initials: H
authors.lastname: Möhwald
authors.affiliation: †Remote Controlled Theranostic Systems Lab, Institute of Nanostructures and Biosystem, Saratov State University, Saratov, 410012 Russia.|∥Max-Planck Institute for Colloids and Interfaces, Potsdam, 14424 Germany.
authors.forename: Alexey M
authors.initials: AM
authors.lastname: Yashchenok
mesh_terms: D048271:Chitosan / Q000737:chemistry*; D005947:Glucose / Q000032:analysis*; D006046:Gold / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry*; D057139:Nanofibers / Q000737:chemistry*; D012235:Rhodamines / Q000032:analysis*; D013059:Spectrum Analysis, Raman / Q000295:instrumentation / Q000379:methods*
chemical_list: D012235:Rhodamines; C026188:rhodamine 6G; D006046:Gold; D048271:Chitosan; D005947:Glucose
keywords: Rhodamine 6G; SERS; chitosan nanofibers; d-Glucose; gold nanoparticles