this manuscript reports on the development of a capacitive sensor for the detection of imidacloprid (IMD) in water samples based on molecularly imprinted polymers (MIPs). MIPs used as recognition elements were synthesized via a photo-initiated emulsion polymerization. The particles were carefully washed using a methanol (MeOH) /acetic acid mixture to ensure complete template removal and were then dried. The average size of the obtained particles was less than 1 µm. The imprinting factor (IF) for IMD was 6 and the selectivity factor (α) for acetamiprid, clothianidin, thiacloprid and thiamethoxam were 14.8, 6.8, 7.1 and 8.2, respectively. The particles were immobilized on the surface of a gold electrode by electropolymerization. The immobilized electrode could be spontaneously regenerated using a mixture of MeOH/10 mM of phosphate buffer (pH = 7.2)/triethylamine before each measurement and could be reused for 32 times. This is the first-time that automated regeneration was introduced as part of a sensing platform for IMD detection. The developed sensor was validated by the analysis of artificially spiked water samples. Under the optimal conditions, the linearity was in the range of 5-100 µM, with a limit of detection (LOD) of 4.61 µM. Nowadays, neonicotinoids (neonics) are the most important class of pesticides in the global market. Their "success" story started in 1991 by introducing imidacloprid (IMD) on the market. Since then, for many years IMD has become the world's largest selling pesticide with the registered uses for over 140 crops in 120 countries 1,2. It is extensively used at a large scale with applications ranging from plant protection, veterinary products, and seed coating. As a result of its extensive usage, IMD can be found as a pollutant in all environmental compartments (soil, water and air) 3. Neonics act by binding to the nicotinic acetylcholine receptors (nAChRs) in their target invertebrates. They mimic the action of neurotransmitters, leading to the continuous stimulation of neurons. In doing so, they could cause the death of their target invertebrates 3. Neonics are highly water soluble, persistent in water, soil, minimally degraded by light and not volatile, which make them easily transported from an area of application to different environmental compartments 4. In addition to that, it was found that like other pesticides they have a negative impact on non-target organisms. IMD and other members of the first generation are highly toxic to bees 5,6. These chemical properties in addition to their negative environmental impacts have raised EU concern 7. Pesticides in general could easily contaminate supplies of drinking water via surface or ground water systems. Depending on the quantity and toxicity level of a pesticide together with the frequency of exposure to the contaminated drinking water, pesticides in water could negatively affect human health and environment. It was found that neonics could have lethal and sublethal effects on many aquatic invertebrates. The acute and chronic neonics t...

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Ulcerative colitis is an autoimmune inflammatory disorder with a negative impact on the life quality of patients. Cinnamaldehyde and hesperetin were chosen due to their antioxidants and anti‐inflammatory effects. This study explored the protective effects of cinnamaldehyde (40 and 90 mg/kg, po) and hesperetin (50 and 100 mg/kg, po) on 2,4,6‐trinitrobenzene sulfonic acid (TNBS)‐induced ulcerative colitis in rats. Cinnamaldehyde and hesperetin significantly improved macroscopic and histopathological examinations with a significant reduction in myeloperoxidase and intracellular adhesion molecule‐1 expression. They significantly reduced colon oxidative stress by a significant elevation in both reduced glutathione content and superoxide dismutase activity with a significant reduction of NO content. Furthermore, cinnamaldehyde and hesperetin alleviated the inflammatory injury by a significant reduction in interleukin‐6 along with suppression of nuclear factor‐κB, receptor for advanced glycation end products, and tumor necrosis factor‐α expression. Moreover, cinnamaldehyde and hesperetin significantly decreased p‐JAK2 and p‐STAT3 while significantly increased suppressors of cytokine signaling 3 (SOCS3) protein expression. In conclusion, cinnamaldehyde and hesperetin counteracted TNBS‐induced ulcerative colitis through antioxidant, anti‐inflammatory properties as well as modulation of the JAk2/STAT3/SOCS3 pathway.

Paracetamol (PAR) and methocarbamol (MET) are co-formulated together in MethorelaxÒ tablets which are widely used as a muscle relaxant and in the treatment of muscle-skeletal pain. On the other hand, 4-aminophenol (4-AP) and guaifenesine (GU) have been reported to be related substances and degradation products of PAR and MET, respectively. The target of this work was to develop and validate a simple, sensitive and selective stability indicating RP-HPLC method for the determination of PAR, MET, 4-AP and GU in their bulk powders and laboratory prepared mixtures. Chromatographic separation was achieved within 10 minutes with the required asymmetry, accuracy and precision on ODS column using 0.05 M KH 2 PO 4 buffer : acetonitrile (72.5 : 27.5, v/v, pH ¼ 6) as the mobile phase at a flow rate of 1 mL min À1 with UV detection at 225 nm. The developed method has been validated as per ICH guidelines and the calibration plots were linear over the concentration ranges of 3-20, 4-25, 0.6-8 and 0.6-8 mg mL À1 for PAR, MET, 4-AP and GU, respectively. The method has been successfully applied in the analysis of MethorelaxÒ tablets and good results were obtained. Moreover, its results have been compared to a previously reported RP-HPLC method and no significant difference was found between the two methods.

A sensitive, accurate and selective high performance thin layer chromatography (HPTLC) method was developed and validated for the simultaneous determination of paracetamol (PAR), its toxic impurity 4-aminophenol (4-AP), pseudoephedrine HCl (PSH) and loratidine (LOR). The proposed chromatographic method has been developed using HPTLC aluminum plates precoated with silica gel 60 F254 using acetone-hexane-ammonia (4:5:0.1, by volume) as a developing system followed by densitometric measurement at 254 nm for PAR, 4-AP and LOR, while PSH was scanned at 208 nm. System suitability testing parameters were calculated to ascertain the quality performance of the developed chromatographic method. The method was validated with respect to USP guidelines regarding accuracy, precision and specificity. The method was successfully applied for the determination of PAR, PSH and LOR in ATSHI(®) tablets. The three drugs were also determined in plasma by applying the proposed method in the ranges of 0.5-6 µg/band, 1.6-12 µg/band and 0.4-2 µg/band for PAR, PSH and LOR, respectively. The results obtained by the proposed method were compared with those obtained by a reported HPLC method, and there was no significance difference between both methods regarding accuracy and precision.