Differential contrast of gold nanorods in dual-band OCT using spectral multiplexing
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In optical coherence tomography (OCT), differential contrast can be generated by resonant nanoparticles using spectral multiplexing. Differential contrast can be of interest for medical applications for improving detection specificity of structures with low endogenous contrast. Differential contrast has been shown using OCT systems with one bandwidth; however, this requires post-processing that is time consuming and reduces image resolution. In this study, we used a dual-band OCT prototype system with two far separated bandwidths in the clinically relevant optical window, and in search for the optimal differential contrast-generating particles for this prototype system, three different gold nanorods (AuNR) samples were investigated. The samples with different particle volume, aspect ratio, and absorption-maximum were imaged in a highly scattering phantom and on chicken muscle. In vitro, differential contrast was observed for the nanorods large (NRL) sample having the absorption-maximum within one bandwidth of the OCT and an average length of 75 nm. For the smaller AuNR (48 nm length) with comparable absorption-maximum, the obtained signal intensities were too low for being visible, although differences in signal intensities between both bandwidths could be measured. NRL optimal concentration for differential contrast using this prototype system is between 100 and 500 µg Au/mL (0.51–2.54 mM). These results demonstrate the potential of real-time imaging of differential contrast in dual-band OCT and motivate in vivo application of plasmon resonant AuNR in order to improve the detection sensitivity for structures that are difficult to identify by OCT such as small blood vessels.
KeywordsDifferential contrast Spectral multiplexing Dual-band optical coherence tomography In vivo measurements Biotissue Small blood vessels
Optical coherence tomography
This research was supported by the German center for interdisciplinary clinical research IZKF and by the “NRW Ziel 2 EFRE (ForSaTum)”. AB and US acknowledge sponsorship by Ziel2.NRW “Regionale Wettbewerbsfähigkeit und Beschäftigung” 2007–2013 co-financed by the European Regional Development Fund (ERDF), Grant no. 005-0908-0117. TW acknowledges financial support provided by the German Research Foundation within the Collaborative Research Center SFB Transregio 37 “Micro- and Nanosystems in Medicine—Reconstruction of Biological Functions”.
Conflict of interest
There is no conflict of interest to be stated.
- Oldenburg A, Hansen MN, Wie A, Boppart SA (2008) Plasmon-resonant gold nanorods provide spectroscopic OCT contrast in excised human breast tumors. Molecular probes for biomedical application II, Proceedings of SPIE. vol. 6867, 68670E1–68670E10Google Scholar
- Rasband WS, ImageJ, Bethesda, MD, USA: U.S. National Institutes of Health; 2009. Available: http://rsb.info.nih.gov/ij/
- Schmitt J (1999) Optical coherence tomography: a review. IEEE J Sel Top Quantum Electron V5, N4, 1205–1215Google Scholar
- Sirotkina MA, Shirmanova MV, Bugrova ML, Elagin VV, Agrba PA, Kirillin MY, Kamensky VA, Zagaynova EV (2010) Continuous optical coherence tomography monitoring of nanoparticles accumulation in biological tissue. J Nanopart Res V13(N1):283–291Google Scholar
- Spöler F, Kray S, Grychotl P, Hermes B, Bornemann J, Först M, Kurz H (2007) Ultrahigh resolution optical coherence tomography at two infrared wavelength regions using a single light source. Optical coherence tomography and coherence techniques III, Proceedings SPIE-OSA Biomedical Optics, SPIE vol 6627, 662704-1–662704-8Google Scholar
- Zagaynova EV, Shirmanova MV, Kirillin MY, Khlebstov BN, Orlova AG, Balalaeva IV, Sirotkina MA, Bugrova ML, Agrba PD, Kamensky VA (2008) Contrasting properties of gold nanoparticles for optical coherence tomography: phantom, in vivo studies and Monte Carlo simulation. Phys Med Biol 53:4995–5009CrossRefGoogle Scholar