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Title: Solution-processed graphene films for electrochemical monitoring of extracellular nitric oxide released by breast cancer cells
Abstract

Nitric oxide (NO) plays an important role in cardiovascular function, immune response, and intercellular signaling. However, due to its short lifetime, real-time detection of NO is challenging. Herein, an electrochemical sensor based on fibronectin-modified, solution-processed graphene ink for NO detection is developed using a facile fabrication method involving spin-coating and hot-plate annealing. The sensor is first electrochemically characterized with a NO donor, spermine NONOate, exhibiting a dynamic range of 10–1000μM. The fibronectin-functionalized graphene supports the attachment and growth of MDA-MB-231 breast cancer cells, as confirmed by optical microscopy. Extracellular NO production is stimulated using the amino acid L-arginine. NO production results in morphological changes to the adhered cells, which are reversible upon the addition of the NO synthase antagonist Nω-nitro-L-arginine methyl ester. The production of NO is also confirmed using real-time amperometric measurements with the fibronectin-functionalized graphene sensors. While this work focuses on NO detection, this potentially scalable platform could be extended to other cell types with envisioned applications including the high-throughput evaluation of therapeutics and biocompatible coatings.

 
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Award ID(s):
2236997
NSF-PAR ID:
10481109
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
IOP Publishing
Date Published:
Journal Name:
2D Materials
Volume:
11
Issue:
1
ISSN:
2053-1583
Format(s):
Medium: X Size: Article No. 015021
Size(s):
["Article No. 015021"]
Sponsoring Org:
National Science Foundation
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