A chitosan-modified nanocomposite of reduced graphene oxide and nanoceria (CH-(rGO@CeO2) NC) was synthesised using co-precipitation method to develop an electrochemical biosensor for the detection of the antibiotic gentamicin (GEN). Various techniques such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), X-Ray Photoelectron Spectroscopy (XPS) and contact angle (CA) were employed for morphological and chemical characterization. Differential pulse voltammetry (DPV) demonstrated excellent electrochemical activity of CH-(rGO@CeO2) NC, making it an ideal transducer material for developing a highly sensitive electrochemical immunosensor. This immunosensor utilized monoclonal antibodies against gentamicin (anti-GEN) that was covalently bound to the CH-(rGO@CeO2) NC modified screen-printed electrode (SPE). Protein kinase A (PKA) was used to regulate immunologic interactions, while BSA was applied to block nonspecific binding sites on the anti-GEN/CH-(rGO@CeO2)/SPE surface. The DPV data for the BSA-anti-GEN/CH-(rGO@CeO2)/SPE immunoelectrode in GEN detection showed a satisfactory linear detection range (1 pM-100 µM), with a limit of detection (LOD) of 0.570 pM and a sensitivity of 2.88 µA pM−1 cm−2. The analysis exhibited a strong linear relationship with an R2 value of 0.973. This CH-(rGO@CeO2) electrochemical immunosensor demonstrated excellent potential for detecting GEN in spiked milk and tap water samples.

Excessive consumption of antibiotics like gentamicin (GEN) can lead to hostile effects as antibiotic resistance. Therefore, the detection is important for which, reduced graphene oxide-Gadolinium oxide nanocomposite (rGO@Gd2O3 NC) was composed through co-precipitation method by using of rGO for the detection of GEN. The structural, morphological and functional group characterization were done using XRD, FT-IR, SEM and TEM techniques. The cyclic voltammetry (CV) shows excellent electrocatalytic activity and superior performance towards GEN detection. Through the use of GEN monoclonal antibodies (anti-GEN) on a screen-printed electrode (SPE), a very sensitive electrochemical immunosensor was fabricated. Covalent interactions were employed to construct the electrochemical immunosensor, while bovine serum albumin (BSA) was employed as a blocking agent on the anti-GEN/rGO@Gd2O3/SPE electrode surface. The analysis of the CV response of the BSA/anti-GEN/rGO@Gd2O3/SPE bioelectrode demonstrated linear detection range from 1 pM – 100 μM, along with limit of detection (LOD) of 0.424 pM and sensitivity of 44.87 μA pM-1 cm− 2. Additionally, rGO@Gd2O3 immunosensor, exhibited a good level of linearity with R2 value of 0.981. These findings indicate the excellent potential of the rGO@Gd2O3 electrochemical immunosensor for accurately detecting GEN in milk samples containing spiked concentrations.

The graphical abstract represents the nanomaterial-based sensing approach for the detection of aminoglycosides (AMGs) antibiotics.

Unconditional use of antibiotics triggered the process of bacterial resistance and causes major health problems. Nowadays, antibiotics majorly used in animals not only for infection treatment but also as mass promotor. The excess amount of antibiotics residue in animal derived foods which accelerate antibiotic resistance (ABR). So, here, a simple and quick carbon quantum dots(CQDs) based fluorometric "On-Off" probe was developed for detection of moxifloxacin (MOXI) in milk and egg samples. The CQDs emits blue emission and are uniformly distributed with average particle size 5.9 +/- 0.22 nm. With MOXI, fluorescence intensity of CQDs at 372 nm decreased due to inner filter effect (IFE) and a new peak appeared at 508 nm correspondence to MOXI. The probe shows linear response with MOXI concentration varies as 0.025 mu M - 15.0 mu M with lower detection limit (LOD) of 6.34 nM. The real sample applicability test proved that the sensors have excellent efficacy for food applications.

The control of antibiotic resistance is at an alarming stage, making the detection of antibiotics as utmost importantance. A sono-chemically-synthesized reduced-graphene oxide-yttrium oxide nanocomposite (rGO@Y2O3 NC) was used to develop an effective electrochemical immunosensing platform for gentamicin detection. The rGO@Y2O3 NC was characterized using different techniques, providing insights into its structural and functional properties. The detection was carried out on a carbon screen printed electrode modified with rGO@Y2O3 NC using differential pulse voltammetry technique. The rGO@Y2O3 NC helped to enhance the electrochemical activity and the functional groups present on rGO helped in efficient electrostatic immobilization of the antibody. Protein kinase A triggered the immunologic interaction and hence helped in achieving higher sensitivity. The developed immunosensor exhibited an impressive limit of detection of 0.457 pM, with a wide range of detection from 1 pM to 100 mu M with a sensitivity of 7.03 mu A pM(-1) cm(-2), representing a substantial enhancement over current technologies. Furthermore, the immunosensor demonstrated practical applicability by effective performance in spiked milk and tap water samples. This highlights its potential for real-world applications in monitoring antibiotic use and ensuring water and food quality control according to regulations. (c) 2024 The Electrochemical Society ("ECS"). Published on behalf of ECS by IOP Publishing Limited. All rights, including fortext and data mining, AI training, and similar technologies, are reserved.

Graphical representation of the overview of lung and oral cancer from detection to medical treatment.

Novel Carbon quantum dots-graphite composite ink-based Screen-printed electrodes (CQDs/SPEs) were used to assemble a highly sensitive electrochemical aptasensor against chlorpyrifos (CPF). The aptasensor showed a broad linear range from 1 pM (0.445 ng/ml) to 500 nM (0.22 mg/ml) with a detection limit (LOD) 0.834 pM (0.37 ng/ml); sensitivity 21.39 μA pM-1 cm- 2 and with good linearity of R2 = 0.973. Moreover, the aptasensor's showed better selectivity among few other pesticides. Further, the aptasensor electrode showed high stability for five months when stored at 4 °C. In the final step, the aptasensor's ability to identify CPF in real samples was evaluated on spiked potato (Solanum tuberosum) extract samples. Potato extract spiked with CPF in the electrochemical aptasensing platform showed excellent linearity of R2 = 0.981. The developed aptasensor showed good response to without spiked potato extract with increasing volumes. Hence, the developed aptasensor demonstrated reasonable applicability in real food and agriculture samples.