A cloth-based electrochemiluminescence sensor for determination of salbutamol residues in pork samples

Solid-state Ru(bpy)32+ electrochemiluminescence sensor for trace detection of fenpropathrin using loofah sponge-like carbon nanofibers and CdS

Loofah sponge-like carbon nanofibers (LF-Co,N/CNFs) were utilized as a carrier for Ru(bpy)32+, and then combined with CdS to create a novel solid-state electrochemiluminescence sensor capable of detecting trace amounts of fenpropathrin. LF-Co,N/CNFs, obtained through the high-temperature pyrolysis of ZIF-67 coaxial electrospinning fibers, were characterized by a loofah-like morphology and exhibited a significant specific surface area and porosity. Apart from serving as a carrier, LF-Co,N/CNFs also functioned as a luminescence accelerator, enhancing the system's luminescence efficiency by facilitating electron transmission and reducing the transmission distance. The inclusion of CdS in the luminescence reaction, in conjunction with Ru(bpy)32+, further boosted the sensor's luminescence signal. The resulting sensor demonstrated a satisfactory signal, with fenpropathrin causing significant quenching of the ECL signal. Under optimized conditions, a linear relationship between the signal quench value and fenpropathrin concentration in the range 1 × 10-12 to 1 × 10-6 M was observed, with a detection limit of 3.3 × 10-13 M (S/N = 3). This developed sensor is characterized by its simplicity, sensitivity, and successful application in detecting fenpropathrin in real samples. The study not only presents a straightforward detection platform for fenpropathrin but also introduces new avenues for the rapid determination of various food contaminants, thereby expanding the utility of carbon fibers in electrochemiluminescence sensors.

Development of cloth-based microfluidic devices for rapid determination of histamine in fish and fishery products

A cloth-based analytical device combined with electrochemiluminescence detection (CAD-ECL) was described for rapid determination  of histamine (HA). The CAD device was produced by screen-printing a conductive carbon ink onto a patterned hydrophobic electrochemical microfluidic chamber to fabricate the three-carbon electrode system on a single hydrophilic cloth. The introduction of carbon nanodots linked to chitosan on the working carbon electrode surface enhanced the catalytic performance and overcame the resistance of the cotton fiber material. On this basis, the enhancement of the electrochemiluminescence (ECL) signal of the tris(2,2'-bipyridyl) ruthenium(II) complex, caused by HA, was observed in a phosphate buffer solution at pH 7.6. The proposed CAD-ECL sensor was successfully applied to the quantification of HA in fish and fishery samples with good linearity between ECL intensity and the logarithm of HA concentration in the range 1.0 to 1000.0 µg L^-1 with a low detection limit of 0.82 µg L^-1.