A paper electrode integrated lateral flow immunosensor for quantitative analysis of oxidative stress induced DNA damage

Abstract

A novel device combining electrochemical and colorimetric detection is developed for the rapid measurement of 8-hydroxy-2′-deoxyguanosine (8-OHdG), a DNA oxidative damage biomarker. The device takes advantage of the speed and low cost of the conventional strip test as well as the high reliability and accuracy of electrochemical assay. Competitive immunoreactions were performed on the lateral flow strip, and the captured 8-OHdG on the control line was determined by chronoamperometric measurement with carbon nanotubes paper as the working electrode. At the same time, the color intensity of the test line was measured by a scanner and analyzed by the ImageJ software. The device was able to detect 8-OHdG concentrations in PBS as low as 2.07 ng mL−1 by the colorimetric method and 3.11 ng mL−1 by the electrochemical method. Furthermore, the device was successfully utilized to detect 8-OHdG in urine with a detection limit of 5.76 ng mL−1 (colorimetric method) and 8.85 ng mL−1 (electrochemical method), respectively. In conclusion, the integrated device with dual detections can provide a rapid, visual, quantitative and feasible detection method for 8-OHdG. The integration of these two methods holds two major advantages over tests based on single method. Firstly, it can provide double confidence on the same assay. Secondly, by involving two methods that differ in principle, the integration could potentially avoid false results coming from one method. In addition, these methods do not require expensive equipment or trained personnel, deeming it suitable for use as a simple, economical, portable field kit for on-site monitoring of 8-OHdG in a variety of clinical settings.

Nanoparticle-based lateral flow biosensors

“…Some later designs (Wang et al, 2011b;Du et al, 2011) tried to fuse the electrode and the strip inside a cassette, including a cutter to section/cut the TL once the immunoassay was completed. Liu et al (2007), Lin et al (2008), Zhu et al (2014) and Akanda et al (2014) integrated the electrodes in the LFS on different ways. In the cases of Liu et al (2007) and Lin et al (2008), QDs containing cadmium were used; after the test was performed and QDs were captured on TL, chlorhydric acid was used to release cadmium ions from QDs, which were detected by the electrodes, located under the TL, when a detection solution (Hg/Bi) was added on it.…”

Electrochemical Lateral Flow Paper Strip for Oxidative-Stress Induced DNA Damage Assessment

“…The method for optimal antibody labeling concentration determination is followed from Zhao. et al [12].…”

“…Our laboratory has studied the detection of 8-OHdG extensively in recent years and we have developed novel platforms to optimize the quality and sensitivity of our detection system [12][13][14]. Utilizing activated carbon fiber microelectrodes within a lateral flow immunoassay, we can now measure cellular 8-OHdG in real-time, utilizing single wall carbon nanotubes (SWCNTs) from the surface of a single cell.…”

Biosensing of DNA oxidative damage: a model of using glucose meter for non-glucose biomarker detection

“…[1][2][3][4][5][6][7][8][9] Among them, paper-based POC devices are a special category due to the advantages of being simple, rapid, on-site, and cost-effective; they have been widely used in home health care and medical testing, [10][11][12] even environmental monitoring. [13][14][15] The lateral flow immunochromatographic assay, also called lateral flow test, is one of the simplest and most popular formats of paper-based POC devices and can be used to detect specific substances, including small molecules, [15][16][17][18] large proteins, [19][20][21] and even whole pathogens, 10 in a sample by using an immunological reaction. However, most of these tests are based on qualitative colorimetry, which is not sufficient in many cases.…”