Rational synthesis of rare-earth lanthanum molybdate covered reduced graphene oxide nanocomposites for the voltammetric detection of Moxifloxacin hydrochloride.

Recently, perovskite structure-based metal oxide nanomaterials and their composites opted for electrocatalyst because of its excellent conductivity, unique, and favored electronic structure. In this attempt, herein we prepared the rare earth mixed metal molybdate covered reduced graphene oxide La2(MoO4)3@rGO nanocomposites by a simple hydrothermal method for the sensitive detection of Moxifloxacin hydrochloride (MOF) in pharmaceutical and human urine samples. The various physicochemical analysis such as SEM, TEM, XRD and Raman spectroscopy confirms the successful formation of (La2(MoO4)3@rGO) nanocomposites. Furthermore, the electroanalytical performance of La2(MoO4)3@rGO modified glassy carbon electrode (La2(MoO4)3@rGO/GCE) was analyzed using the cyclic voltammetry (CV) and differential pulse voltammetry (DPV) which shows excellent results with a wide range of 1.0 × 10-8 M to 6.0 × 10-4 M and the detection limit of 2.84 × 10-9 M towards the MOF detection. Furthermore, the developed sensor expressed good selectivity, repeatability, stability and reproducibility. Finally, the real sample analysis of the developed sensor was tested in the MOF tablets and human urine samples, which shows the appreciable recoveries.

Effect of cell-permeable grouper Manganese Superoxide Dismutase on environmental stress in fish.

Nitrite levels are generally high in high-density aquaculture. Nitrite is a potential stress-inducing factor and can cause oxidative stress because excessive reactive oxygen species (ROS) formation through nitrite induction cannot be scavenged by the endogenous antioxidant system, thus leading to cell damage or death. Manganese Superoxide Dismutase (MnSOD) is a highly efficient endogenous ROS scavenger that quenches mitochondrial ROS and protective against oxidative stress. To enhance the efficiency of MnSOD in removing ROS and reducing oxidative caused by nitrite, in this study, we cloned grouper MnSOD (gMnSOD) fused with a cell-penetrating peptide, TAT, to construct a TAT-gMnSOD fusion protein and assessed its potential to eliminate excess ROS induced by high nitrite concentrations and enhance the resistance of zebrafish to environmental stressors. Our results revealed that TAT-gMnSOD penetrated the grouper fin (GF-1) cells, scavenged nitrite-induced intracellular ROS, and enhanced cell viability on NaNO2 treatment. Furthermore, pretreatment of zebrafish with TAT-gMnSOD fusion protein reduced the MDA content and increased the survival rate. In addition, the TAT-gMnSOD fusion protein reduced 2-phenoxyethanol toxicity and attenuated excessive anesthesia among zebrafish. In conlusion, our cell-permeable TAT-gMnSOD fusion protein effectively counters oxidative stress, prevents environmental stress-induced damage, and increases aquaculture benefits.