Targeted and effective therapy of diseases demands utilization of rapid methods of identification of the given markers. Surface enhanced Raman spectroscopy (SERS) in conjunction with streptavidin-biotin complex is a promising alternative to culture or PCR based methods used for such purposes. Many biotinylated antibodies are available on the market and so this system offers a powerful tool for many analytical applications. Here, we present a very fast and easy-to-use procedure for preparation of streptavidin coated magnetic polystyrene-Au (or Ag) nanocomposite particles as efficient substrate for surface SERS purposes. As a precursor for the preparation of SERS active and magnetically separable composite, commercially available streptavidin coated polystyrene (PS) microparticles with a magnetic core were utilized. These composites of PS particles with silver or gold nanoparticles were prepared by reducing Au(III) or Ag(I) ions using ascorbic acid or dopamine. The choice of the reducing agent influences the morphology and the size of the prepared Ag or Au particles (15-100 nm). The prepare composites were also characterized by HR-TEM images, mapping of elements and also magnetization measurements. The content of Au and Ag was determined by AAS analysis. The synthesized composites have a significantly lower density against magnetic composites based on iron oxides, which considerably decreases the tendency to sedimentation. The polystyrene shell on a magnetic iron oxide core also pronouncedly reduces the inclination to particle aggregation. Moreover, the preparation and purification of this SERS substrate takes only a few minutes. The PS composite with thorny Au particles with the size of approximately 100 nm prepared was utilized for specific and selective detection of Staphylococcus aureus infection in joint knee fluid (PJI) and tau protein (marker for Alzheimer disease).

• MeSH
• Alzheimer Disease blood   diagnosis   genetics   MeSH
• Biomarkers analysis   MeSH
• Dopamine chemistry   MeSH
• Ascorbic Acid chemistry   MeSH
• Humans MeSH
• Magnetic Iron Oxide Nanoparticles chemistry   ultrastructure   MeSH
• Polystyrenes chemistry   MeSH
• tau Proteins analysis   blood   genetics   MeSH
• Spectrum Analysis, Raman methods   MeSH
• Staphylococcal Infections diagnosis   microbiology   MeSH
• Staphylococcus aureus growth & development   pathogenicity   MeSH
• Streptavidin chemistry   MeSH
• Silver chemistry   MeSH
• Synovial Fluid microbiology   MeSH
• Particle Size MeSH
• Gold chemistry   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Biomarkers MeSH
• Dopamine MeSH
• Ascorbic Acid MeSH
• MAPT protein, human MeSH Browser
• Polystyrenes MeSH
• tau Proteins MeSH
• Streptavidin MeSH
• Silver MeSH
• Gold MeSH