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...
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...
Ultrafast Photoinduced Carrier Dynamics of Organic Semiconductors Measured by Time-Resolved Terahertz Spectroscopy
Esentürk, Okan; Lane, Paul A; Heilweil, Edwin J (null, 2010-01-01)
Intrinsic properties of organic semiconductors are investigated by Time-Resolved Terahertz Spectroscopy (TRTS) to assess their relative mobilities and efficiencies. Our results are well correlated with device measurements and show the effectiveness and advantages of using this non-contact optical technique to rapidly identify prospective materials. After a brief introduction of the TRTS technique, we summarize our results from relative mobility measurements of the organic semiconductor polymers poly(3-hexyl...
Multichromic benzimidazole-containing polymers: Comparison of donor and acceptor unit effects
Nurioglu, Ayda Goycek; Akpinar, Hava; Sendur, Merve; Toppare, Levent Kamil (2012-09-01)
This study reports a comparative study on electrochromic properties of two donoracceptordonor (DAD)-type polymers namely poly(2-heptyl-4,7-di(thiophen-2-yl)-1H-benzo [d]imidazole) (BImTh) and poly(4,7-bis(2,3-dihydrothieno[3,4-b] [1,4]dioxin-5-yl)-2-heptyl-1H-benzo[d]imidazole) (BImEd). DAD-type monomers were polymerized electrochemically on indium tin oxide-coated glass slides to determine the optical properties of the polymers. Electrochemical rho-doping experiments were performed to determine the band ga...
Theoretical limits to sensitivity and resolution in magneto-acousto-electrical tomography
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...
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.