Detection of gold nanorods uptake by macrophages using scattering analyses combined with diffusion reflection measurements as a potential tool for in vivo atherosclerosis tracking

Abstract

In this study, we report a potential noninvasive technique for the detection of vulnerable plaques using scatter analyses with flow cytometry (FCM) method combined with the diffusion reflection (DR) method. The atherosclerotic plaques are commonly divided into two major categories: stable and vulnerable. The vulnerable plaques are rich with inflammatory cells, mostly macrophages (MΦ), which release enzymes that break down collagen in the cap. The detection method is based on uptake of gold nanorods (GNR) by MΦ. The GNR have unique optical properties that enable their detection using the FCM method, based on their scattering properties, and using the DR method, based on their unique absorption properties. This work demonstrates that after GNR labeling of MΦ, 1) the FCM scatter values increased up to 3.7-fold with arbitrary intensity values increasing from 1,110 to 4,100 and 2) the DR slope changed from an average slope of 0.196 (MΦ only) to an average slope of 0.827 (MΦ labeled with GNR) ( P <0.001 for both cases). The combination of FCM and DR measurements provides a potential novel, highly sensitive, and noninvasive method for the identification of atherosclerotic vulnerable plaques, aimed to develop a potential tool for in vivo tracking.

A SERS-based 3D nanobiosensor: towards cell metabolite monitoring

“…The absorbance peaks of the synthetized NPs are according to those described in the literature for optical and SERS detection tools. [29][30][31] In particular, AuNSs were selected due to the extra SERS enhancement offered by their tips, and the Ag-coated AuNRs were selected (Au@AgNRs) due to the better SERS enhancement of silver vs. gold, as previously demonstrated. 23,32 In this work, in order to obtain a good dispersion and distribution of the NPs within the GG-SLH, the NPs were added in situ before the gelation reaction of the precursor hydrogels.…”

“…The absorbance peaks of the synthetized NPs are according to those described in the literature for optical and SERS detection tools. 29–31 In particular, AuNSs were selected due to the extra SERS enhancement offered by their tips, and the Ag-coated AuNRs were selected (Au@AgNRs) due to the better SERS enhancement of silver vs. gold, as previously demonstrated. 23,32…”

Media Characterization under Scattering Conditions by Nanophotonics Iterative Multiplane Spectroscopy Measurements

“…In the diffusion reflection theory, the change in the source size is taken into account by a constant that depends on the source size and intensity. 19,37−39 It is known that sources with wider beam waist, that incident a medium experience smaller beam expansion than narrow beam sources. Furthermore, the beam expansion occurs deeper in the medium.…”

Spectral computed tomography for quantitative decomposition of vulnerable plaques using a dual-energy technique: a Monte Carlo simulation study

“…These contrast agents can offer anatomical information about the coronary artery; however, they cannot quantify the volume fractions of the vulnerable plaque in the coronary artery. This often leads to underestimation of the inflammation status of the fibrous cap [13]. Recently, gold-based nanoparticle contrast agents have been introduced for vulnerable plaque imaging by CT.…”