# AuNPs@Al-TDC Metal–Organic Framework: A Hybrid Nanostructure for 3D-Printed Electrochemical Sensors Targeting Diuron

## TL;DR

This paper introduces a 3D-printed electrochemical sensor using recycled materials and a hybrid nanostructure to detect the pesticide Diuron efficiently and sustainably.

## Contribution

A novel hybrid nanostructure (AuNPs@Al-TDC) integrated into a 3D-printed sensor for pesticide detection using recycled ABS filament.

## Key findings

- The sensor showed a linear dynamic range of 1.0 to 20.0 μmol L–1 for Diuron detection.
- The detection limit was as low as 0.040 μmol L–1 with precision below 7% relative standard deviation.
- Recovery assays in water samples showed accuracy between 97% and 105%.

## Abstract

The integration of
sustainability principles, green chemistry,
and circular economy concepts enables the recycling of polymers such
as acrylonitrile-butadiene-styrene (ABS) into innovative and functional
devices. In this context, advances in composite materials and conductive
filaments are essential for the development of inexpensive and sustainable
electrochemical sensors. This study presents a sensor (AuNPs@Al-TDC/3D-CPE)
fabricated via 3D printing using recycled ABS filaments, modified
with the Al-TDC metal–organic framework (MOF) and gold nanoparticles
(AuNPs). The MOF composite was synthesized from tetrachloroauric acid,
thiophene-2,5-dicarboxylic acid, dimethylformamide, and formic acid
under microwave-assisted hydrothermal conditions, and in a postsynthesis
modification, the AuNPs were incorporated. The hybrid materials underwent
a comprehensive physicochemical evaluation through spectroscopic,
imaging, and electrochemical approaches, confirming both the successful
incorporation of the modifiers and the structural integrity of the
sensing platform. For its analytical application, the pesticide Diuron
was selected as the target molecule for the development of a differential
pulse voltammetry (DPV) protocol, whose procedure was systematically
optimized using the AuNPs@Al-TDC/3D-CPE. The sensor exhibited a well-defined
linear dynamic range between 1.0 and 20.0 μmol L–1, achieving a detection limit of 0.040 μmol L–1. Precision was confirmed by relative standard deviations consistently
below 7%. Accuracy was further validated through recovery assays in
fortified water samples, yielding values between 97% and 105%. The
proposed sensor is efficient, cost-effective, and environmentally
friendly, representing a promising alternative for the monitoring
of emerging contaminants in alignment with the sustainable development
goals.