Abstract: This invention relates to the development of a new Raman enhancing reagent and a surface-enhanced Raman scattering (SERS) method for rapid and ultra-sensitive detection and identification of perchlorate (ClO4?) and other anions such as technetium (TcO4?), uranium and nitrate in environmental samples. The method involves the synthesis of controlled gold nanoparticles which are modified with amine functional groups such as 2-(dimethylamino)ethanethiol and N,N,N-trimethylaminethiol. These functionalized Au nanoparticles were found to be reactive with perchlorate and other anions and can be used to detect these anions by Raman spectroscopy at ultra low concentrations in complex environmental matrices. This invention overcomes the limitations of currently-available analytical techniques by offering an inexpensive, rapid, ultra-sensitive, and real-time identification and detection of perchlorate and other anions.

Abstract: A method for in situ detection of viable pathogenic bacteria in a selective medium by measuring cathodic peak current of oxygen on cyclic voltammograms during bacterial proliferation with an electrochemical voltammetric analyzer. The rapid oxygen consumption at a time during the growth of bacteria resulted in a sharp decline of the cathodic peak current curves. The detection times (threshold values) obtained from the cathodic peak current curve were inversely related to the concentrations of the pathogenic bacteria in the medium. This method for detection of pathogenic bacteria is more sensitive than nucleic acid-based polymerase chain reaction (PCR) methods and any of antibody-based methods such as enzyme-linked immunosorbent assay (ELISA) technology, electrochemical immunoassays, immunosensors, and it has a sensitivity similar to conventional culture methods and impedimetric methods but is more rapid than both of them.

Abstract: A method for in situ detection of viable pathogenic bacteria in a selective medium by measuring cathodic peak current of oxygen on cyclic voltammograms during bacterial proliferation with an electrochemical voltammetric analyzer. The rapid oxygen consumption at a time during the growth of bacteria resulted in a sharp decline of the cathodic peak current curves. The detection times (threshold values) obtained from the cathodic peak current curve were inversely related to the concentrations of the pathogenic bacteria in the medium. This method for detection of pathogenic bacteria is more sensitive than nucleic acid-based polymerase chain reaction (PCR) methods and any of antibody-based methods such as enzyme-linked immunosorbent assay (ELISA) technology, electrochemical immunoassays, immunosensors, and it has a sensitivity similar to conventional culture methods and impedimetric methods but is more rapid than both of them.