Label-free impedimetric immunosensor for detection of the textile azo dye Disperse Red 1 in treated water

Abstract

The development of methodologies to detect and quantify azo dyes in treated water is required because some of these dyes exhibit genotoxic activity, even at low concentrations. Here, the construction and characterization of an impedimetric immunosensor for determination of the textile azo dye Disperse Red 1 (DR1) by means of a label-free assay is reported. Anti-DR1 antibodies (Ab anti-DR1) were successfully coupled to glassy carbon electrode (GCE) surface by bonding using electrochemically generated activated carboxylic groups. The concentration of DR1 was measured by the increase in charge transfer resistance (R CT) when the immune reaction occurred, using Fe(CN) 6 3−/4− as a probe. Electrochemical characterizations of the sensor by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were performed, and infra-red spectra were obtained to complement the electrochemical results showing immobilization of the antibodies. Under optimal conditions, the change in R CT presented a linear relationship with DR1 concentration in the range from 8.40 to 100 nM, and the sensor provided low limit of detection (LOD = 2.52 nM) and quantification (LOQ = 8.40 nM). No significant interference from other azo dyes was observed. The performance of the immunosensor was evaluated using tap water spiked with 20.0 nM DR1 and a satisfactory recovery of 98.5% was found. The proposed immunosensor is simple, relatively inexpensive, and shows good sensitivity for this application.

Immunosensor for Detection of the Textile Dye Disperse Orange 1 Based on Non‐conventional Competitive Assay

“…Limits of detection (LOD) and quantification (LOQ) of 0.87 ng mL −1 and 2.9 ng mL −1 , calculated based on 3sd/s or 10sd/s, respectively, where sd is the standard deviation of the blank and s is the slope of the calibration curve, were obtained for the determination of DO1. Those values were similar to previously reported for dyes with others modified electrodes .…”

“…Generally, the wastewater from textile factories contains a mixture of different dyes, auxiliaries, additives, and additional chemicals that were added during the textile production processes . On previous investigation , dyes that belong to the same class of the analyte, with similar structures and molecular weights showed no interference. Herein, to verify the selectivity of the developed competitive immunosensor, four orange dyes from different classes were applied in the capture step using the MP‐CS‐GA‐AbDO1‐HRP bioconjugate.…”

Simple, fast and environmentally friendly method to determine ciprofloxacin in wastewater samples based on an impedimetric immunosensor

“…43 The choice of supporting electrolyte [Fe(CN 6 )] 3À/4À in this paper was based on the widely recognized electrochemical response, which demonstrates that the developed sensor is in agreement with previous studies described in the literature. 38,[44][45][46] The EIS behavior shown in Fig. 1B demonstrates that the electrode modication was successful since there is an increase in the Nyquist plot capacitive arc diameter aer each modication step.…”

Photocatalytic Degradation of Methyl Violet Dye Using Calcium Carbonate Nanoparticles Synthesized by Precipitation Method

“…Among the various kinds of dyes, azo dyes are popular dyes that are most commonly used in the textile industries. 12,13 However, regarding its disposal after usage, industries have adopted various physical techniques such as coagulation by chemical agents, usage of ion exchange, activated carbon, ultra ltration, reverse osmosis, etc. 14,15 Although, these techniques convert the organic compounds present in the water into a secondary pollutant like sludge, needs further treatment.…”