Back to Journals » International Journal of Nanomedicine » Volume 14

Ultrasmall gold nanorods: synthesis and glycocalyx-related permeability in human endothelial cells

Authors Cheng MJ, Bal NN, Prabakaran P, Kumar R, Webster TJ, Sridhar S, Ebong EE

Received 18 August 2018

Accepted for publication 15 November 2018

Published 17 January 2019 Volume 2019:14 Pages 319—333


Checked for plagiarism Yes

Review by Single anonymous peer review

Peer reviewer comments 3

Editor who approved publication: Dr Lei Yang

Ming J Cheng,1,* Nandita N Bal,1,* Priya Prabakaran,1 Rajiv Kumar,2,3 Thomas J Webster,1,4 Srinivas Sridhar,1,2 Eno E Ebong1,2,5

1Department of Chemical Engineering, Northeastern University, Boston, MA, USA; 2Department of Physics, Northeastern University, Boston, MA, USA; 3Millipore Sigma, Milwaukee, WI, USA; 4Center of Excellence for Advanced Materials Research, King Abdulaziz University, Jeddah, Saudi Arabia; 5Department of Neuroscience, Albert Einstein College of Medicine, New York, NY, USA

*These authors contributed equally to this work

Background: Clinical data show shed endothelial glycocalyx (GCX) components in blood samples of atherosclerotic patients, linking atherosclerotic development to endothelial GCX integrity. Healthy GCX has pores no >7 nm, and shed GCX has even larger pores. Therefore, we suggest targeting and treating atherosclerosis-prone blood vessels by using nanoscale vehicles to deliver drugs via the nanoscale GCX as it becomes dysfunctional.
Materials and methods: To test our idea, we investigated permeability of nanoparticles in endothelium, as related to a GCX expression. The present work involves nanorods, which are expected to interact with larger portions of endothelial cell (EC) membranes, due to surface area of the nanorod long axis. Conventional nanorod diameters are orders of magnitude larger than the GCX pore size, so we adapted conventional synthesis methods to fabricate ultrasmall gold nanorods (GNRs). Our ultrasmall GNRs have an aspect ratio of 3.4, with a length of 27.9±3.1 nm and a diameter of 8.2±1.4 nm. In addition, we produced GNRs that are biocompatible and fluorescently visible, by coating the surface with functionalized polyethylene glycol and Alexa Fluor 647. To study GNR–GCX interactions, we used human ECs, for species relevance.
Results: Under life-like flow conditions, the human ECs are densely covered with a 1.3 µm thick layer of GCX, which coincides with minimal GNR permeability. When the GCX is weakened from lack of flow (static culture) or the presence of GCX degradation enzyme in the flow stream, the GCX shows 40% and 60% decreased thickness, respectively. GCX weakness due to lack of flow only slightly increases cellular permeability to GNRs, while GCX weakness due to the presence of enzyme in the flow leads to substantial increase in GNR permeability.
Conclusion: These results clarify that the GCX structure is an avenue through which drug-carrying nanoparticles can be delivered for targeting affected blood vessels to treat atherosclerosis.

Keywords: human endothelial cells, gold nanoparticles, nanorods, glycocalyx, heparan sulfate

Creative Commons License This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.

Download Article [PDF]  View Full Text [HTML][Machine readable]