Ultrasensitive and selective homogeneous sandwich immunoassay detection by Surface Enhanced Raman Scattering (SERS)

Pekdemir, Mustafa Ersin
Erturkan, Deniz
Külah, Haluk
Özgen, Canan
Tamer, Ugur
In this report, a simple and highly selective homogeneous sandwich immunoassay was developed for ultrasensitive detection of Staphylococcal Enterotoxin B (SEB) using Surface Enhanced Raman Scattering (SERS). The assay uses polyclonal-antibody functionalized magnetic gold nanorod particles as capture probes for SEB, which can be collected via a simple magnet. After separating SEB from the sample matrix, they are sandwiched by using binding-specific antibody-antigen pairs with the help of gold nanorod particles. Gold nanorod particles are bifunctional by design and contain self-assembled monolayers (SAMs) of a SERS tag molecule (5,5-dithiobis (2-nitrobenzoic acid), DTNB) and carboxylic functionalities of DTNB for coupling with a suitable antibody. The correlation between the SEB concentration and SERS signal was found to be linear within the range of 3 fM to 0.3 mu M. The limit of detection for the assay was determined to be 768 mu M (ca., 9250 SEB molecules per 20 mu L sample volume). The gold heterogeneous assay system for SEB detection was also compared with the same SERS probes and gold-coated surfaces as capture substrates. The developed method was further evaluated for detecting SEB in artificially contaminated milk. Finally, the method was used for investigating the SEB specificity on bovine serum albumin (BSA) and avidin.


Experimental determination of the dose deposition profile of a Sr-90 beta source
GAZA, R; Bulur, Enver; McKeever, S. W. S.; Soares, C. G. (Oxford University Press (OUP), 2006-09-01)
Three different methods for characterising the dose deposition profile of a Sr-90/Y-90 radioactive source are described: GAFChromic film dosimetry, Thermoluminescence (TL) and Optically Stimulated Luminescence (OSL). For the film measurements, GAFChromic film samples were stacked at different depths between polyethylene terephthalate (PET) foils. For TL, the thickness of a TLD-500 dosemeter was gradually reduced by polishing and the TL from chips of different thickness was used in conjunction with a mathema...
Raman Frequencies calculated as a function of pressure for the rotatory lattice mode in ammonia solid II near the melting point
Yurtseven, Hasan Hamit (2004-04-01)
This study gives our calculations for the Raman frequencies of the rotatory lattice mode in ammonia solid II near the melting point. The Raman frequencies of this mode are calculated as a function of the pressure using the volume data for the fixed temperatures of 230.4 K, 263.4 K, and 297.5 K by means of our Gruneisen relation. Our calculated frequencies can be examined experimentally when the Raman measurements are performed at various pressures for the constant temperatures considered.
Optoelectrochemical properties of poly(5,12-dihydrothieno[3 ',4 ':2,3][1,4] dioxocino[6,7-b]quinoxaline-co-2,2 ' bithiophene) and its electrochromic device application
Ak, Metin; Ak, Mine Sulak; GÜLLÜ, Mustafa; Toppare, Levent Kamil (IOP Publishing, 2007-12-01)
In this study we investigated the electrochromic properties and electrochromic device application of poly(5,12-dihydrothieno[3',4':2,3][1,4]dioxocino[6,7-b]quinoxaline (DDQ)-co-2,2'-bithiophene (13T)). Copolymerization was successfully achieved electrochemically in acetonitrile containing 0.1 M tetrabutyl ammonium tetrafluoroborate as the supporting electrolyte by direct anodic oxidation on platinum and indium tin oxide coated glass electrodes. The structure and morphology of the copolymer were investigated...
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GHALICHI, Elyar; Gençer, Nevzat Güneri (2017-10-21)
In this study, the performance of magneto-acousto-electrical tomography (MAET) is investigated quantitatively by considering interrelations between its sensitivity, resolution and conductivity contrast. An analytical solution for the forward problem of MAET is derived for two-dimensional (2D) concentric bodies by the separation of variables method. The electric potential and the acoustic pressure are separated into their angular and radial components. The series coefficients for these solutions are obtained...
Fatty acid methyl ester analysis of bacterşal isolates from salt lake, Turkey and characterization of their extracellular enzymes
Bahçeci, Hümeyra; Gültekin, Güzin Candan; Department of Biotechnology (2004)
In this study, 11 bacterial isolates from Salt Lake,Turkey were identified by using fatty acid methyl ester (FAME) analysis. They were screened for production of industrially important enzymes xylanase, cellulase, a-amylase and protease. These enzymes were characterized in terms of enzyme activity, stability, optimum temperature and optimum pH. One of the isolates was identified as Bacillus pumilus, and two of them were identified as Bacillus subtilis. Other isolates were determined to be Bacillus lichenifo...
Citation Formats
M. E. Pekdemir, D. Erturkan, H. Külah, İ. H. BOYACI, C. Özgen, and U. Tamer, “Ultrasensitive and selective homogeneous sandwich immunoassay detection by Surface Enhanced Raman Scattering (SERS),” ANALYST, pp. 4834–4840, 2012, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/31670.