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.


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Colpan, Can O.; Yesin, Tulay (2006-01-01)
In this paper, several configurations of combined cycle cogeneration systems are investigated by energy, exergy and thermoeconomic analyses. In each of these configurations, varying steam demand is considered rather than fixed steam demand. Among the different approaches for thermoeconomic analysis in the literature, the specific exergy costing method is applied. Since the systems have more than one product (process steam and electrical power), systems are divided into several sub-systems and cost balances ...
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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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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...
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.
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.