title: Paper-based microfluidic approach for surface-enhanced raman spectroscopy and highly reproducible detection of proteins beyond picomolar concentration.
abstract: Although microfluidic approach is widely used in various point of care diagnostics, its implementation in surface enhanced Raman spectroscopy (SERS)-based detection is challenging. This is because SERS signal depends on plasmonic nanoparticle aggregation induced generation of stable electromagnetic hot spots and in currently available microfluidic platform this condition is difficult to adapt. Here we show that SERS can be adapted using simple paper based microfluidic system where both the plasmonic nanomaterials and analyte are used in mobile phase. This approach allows analyte induced controlled particle aggregation and electromagnetic hot spot generation inside the microfluidic channel with the resultant SERS signal, which is highly reproducible and sensitive. This approach has been used for reproducible detection of protein in the pico to femtomolar concentration. Presented approach is simple, rapid, and cost-effective, and requires low sample volume. Method can be extended for SERS-based detection of other biomolecules.
authors.affiliation: Centre for Advanced Materials, Indian Association for the Cultivation of Science , Kolkata 700032, India.
authors.forename: Arindam
authors.initials: A
authors.lastname: Saha
authors.forename: Nikhil R
authors.initials: NR
authors.lastname: Jana
mesh_terms: D001710:Biotin / Q000737:chemistry; D002855:Chromatography, Thin Layer; D003208:Concanavalin A / Q000737:chemistry; D060733:Electromagnetic Radiation; D005947:Glucose / Q000737:chemistry; D006046:Gold / Q000737:chemistry; D046210:Microfluidic Analytical Techniques; D044085:Microfluidics / Q000295:instrumentation / Q000379:methods*; D053758:Nanoparticles / Q000737:chemistry; D049329:Nanostructures; D010209:Paper; D011506:Proteins / Q000737:chemistry; D015203:Reproducibility of Results; D012822:Silicon Dioxide / Q000737:chemistry; D012834:Silver / Q000737:chemistry; D013059:Spectrum Analysis, Raman; D013438:Sulfhydryl Compounds / Q000737:chemistry; D013499:Surface Properties; D014466:Ultraviolet Rays
chemical_list: D011506:Proteins; D013438:Sulfhydryl Compounds; D003208:Concanavalin A; D012834:Silver; D001710:Biotin; D006046:Gold; D012822:Silicon Dioxide; D005947:Glucose
keywords: SERS; functionalization; microfluidics; nanoparticle; protein detection