Electrochemical sensor based on PEDOT/CNTs-graphene oxide for simultaneous determination of hazardous hydroquinone, catechol, and nitrite in real water samples.

Hydroquinone (HQ), catechol (CC) and nitrite (NT) are considered aquatic environmental pollutants. They are highly toxic, harm humans' health, and damage the environment. Thus, in the present work we introduce a simple and efficient electrochemical sensor for determination of HQ, CC, and NT simultaneously in wastewater sample. The sensor is fabricated by modifying the surface of a glassy carbon electrode (GCE) by two successive thin films from poly(3,4-ethylenedioxythiophene) (PEDOT) and a mixture of carbon nanotubes-graphene oxide (CNT-GRO). Under optimized conditions the HQ, CC, and NT are successfully detected simultaneously in wastewater sample with changing their concentrations in the ranges (0.04 → 100 µM), (0.01 → 100 µM) and (0.05 → 120 µM), the detection limits are 8.5 nM, 3.8 nM and 6.1 nM, respectively. Good potential peak separations: 117 mV and 585 mV are obtained between the HQ-CC, and CC-NT. The sensor has an excellent catalytic capability toward the oxidation of HQ, CC, and NT due to good synergism between its composite components: PEDOT, GRO and CNTs. The features of the sensor are large active surface area, good electrical conductivity, perfect storage stability, good reproducibility, anti-interference capability and accepted recovery rate for HQ, CC, and NT determination in wastewater sample.

Electrochemical sensor for simultaneous determination of trifluoperazine and dopamine in human serum based on graphene oxide-carbon nanotubes/iron-nickel nanoparticles.

Trifluoperazine (TFLP) is an important psychiatric medication that balances the dopamine (DA) level in the brain for patients suffering from neurological disorder diseases. An efficient electrochemical sensor is developed for detecting TFLP in real human serum samples. The sensor is fabricated by casting the GC surface with two consecutive thin layers, namely a graphene oxide-carbon nanotubes mixture (GRO-CNT), and iron-nickel nanoparticles (Fe-Ni). The diffusion-controlled oxidation process of TFLP at the composite surface includes one electron transfer process. Under optimized conditions, the sensor in human serum shows excellent catalytic effect for simultaneous determination of TFLP and dopamine (DA) in the same concentration range (0.5 µM to 18 µM) with low detection limits of 0.13 µM and 0.32 µM respectively. The combined effect of a large conductive surface area and the excellent catalytic activity of the nanocomposite improves the sensor's performance. The sensor exhibits a stable current response over four weeks, excellent reproducibility, and insignificant interference from common species present in human serum samples. The reliability test of using the sensor in serum samples shows good recovery of TFLP.

Electrochemical sensor for simultaneous determination of antiviral favipiravir drug, paracetamol and vitamin C based on host-guest inclusion complex of ß-CD/CNTs nanocomposite.

Favipiravir (FVI) is extensively used as an effective medication against several diverse infectious RNA viruses. It is widely administered as an anti-influenza drug. Combination therapy formed from FVI, paracetamol (PAR) and vitamin C (VC) is needed for treating patients diseased by RNA viruses. Thus, an efficient electrochemical sensor is developed for detecting FVI in human serum samples. The sensor is fabricated by casting a thin layer of carbon nanotubes (CNTs) over a glassy carbon (GC) electrode surface followed by electrodeposition of another layer of ß-cyclodextrin (ß-CD). Under optimized conditions, the sensor shows excellent catalytic effect for FVI, PAR and VC oxidation in the concentration ranges (0.08 µM → 80 µM), (0.08 µM → 50 µM) and (0.8 µM → 80 µM) with low detection limits of 0.011 µM, 0.042 µM and 0.21 µM, respectively. The combined effect of host-guest interaction ability of ß-CD for the drugs, and a large conductive surface area of CNTs improves the sensing performance of the electrode. The sensor exhibits stable response over 4 weeks, good reproducibility, and insignificant interference from common species present in serum samples. The reliability of using the sensor in serum samples shows good recovery of FVI, PAR and VC.

Molecular and chemical characterization of mutant and nonmutant genotypes of saffron grown in Saudi Arabia.

Saffron (Crocus sativus L.) is an important spice and medicinal plant that is cultivated in Asia, Europe, North Africa, and North America. Its morphological and biochemical parameters, such as the changes in the floral parts (six tepals, three stamens, three stigmata), biomass, and chlorophyll content, are primarily affected by environmental conditions. A polymerase chain reaction-rapid amplified polymorphic DNA (PCR-RAPD) approach was used to analyze the extent of the polymorphisms between C. sativus genotypes grown in the Saudi climate. In this research study, the DNA fingerprints of the stigmata of C. sativus genotypes [K1 & K2 = C. sativus var. cashmerianus, C1 = C. sativus (nonmutant), T1 = mutant (T0-2B), T2 = mutant (T1-2B), T3 = mutant (T4-2A)] were determined according to the floral parts, and a total of 10 decamer primers were used for PCR-RAPD analysis. Only three pairs of arbitrary primers showed polymorphisms (33.3%-88.2%) in the total genomic DNA extracted from these genotypes. Jaccard's similarity index (JSI) ranged from 0.88 to 1.0. An unweighted pair group method with arithmetic mean (UPGMA) similarity and dendrogram matrix showed that two genotypes (T1-2B and T4-2A) were closely related to each other and to the strain CM-cashmerianus, while the T0 of C. sativus genotype showed divergence.

Efficient regeneration and improved sonication-assisted Agrobacterium transformation (SAAT) method for Catharanthus roseus.

Catharanthus roseus is an important medicinal plant known for its pharmacological qualities such as antimicrobial, anticancerous, antifeedant, antisterility, antidiabetic activities. More than 130 bioactive compounds like vinblastine, vindoline and vincristine have been synthesized in this plant. Extensive studies have been carried out for optimization regeneration and transformation protocols. Most of the protocol described are laborious and time-consuming. Due to sophisticated protocol of regeneration and genetic transformation, the production of these bioactive molecules is less and not feasible to be commercialized worldwide. Here we have optimized the efficient protocol for regeneration and transformation to minimize the time scale and enhance the transformation frequency through Agrobacterium and sonication-assisted transformation (SAAT) method. In this study, hypocotyl explants responded best for maximal production of transformed shoots. The callus percentage were recorded 52% with 1.0 mg L-1 (BAP) and 0.5 mg L-1 (NAA) while 80% shoot percentage obtained with 4.0 mg L-1 (BAP) and 0.05 mg L-1 (NAA). The microscopic studies revealed that the expression of GFP was clearly localized in leaf tissue of the C. roseus after transformation of pRepGFP0029 construct. Consequently, transformation efficiency was revealed on the basis of GFP localization. The transformation efficiency of SAAT method was 6.0% comparable to 3.5% as conventional method. Further, PCR analysis confirmed the integration of the nptII gene in the transformed plantlets of C. roseus.

In vitro Evaluation of Cytotoxic Activities of Essential Oil from Moringa oleifera Seeds on HeLa, HepG2, MCF-7, CACO-2 and L929 Cell Lines.

Moringa oleifera Lam. (Moringaceae) is widely consumed in tropical and subtropical regions for their valuable nutritional and medicinal characteristics. Recently, extensive research has been conducted on leaf extracts of M. oleifera to evaluate their potential cytotoxic effects. However, with the exception of antimicrobial and antioxidant activities, little information is present on the cytotoxic activity of the essential oil obtained from M. oleifera seeds. Therefore, the present investigation was designed to investigate the potential cytotoxic activity of seed essential oil obtained from M. oleifera on HeLa, HepG2, MCF-7, CACO-2 and L929 cell lines. The different cell lines were subjected to increasing oil concentrations ranging from 0.15 to 1 mg/mL for 24h, and the cytotoxicity was assessed using MTT assay. All treated cell lines showed a significant reduction in cell viability in response to the increasing oil concentration. Moreover, the reduction depended on the cell line as well as the oil concentration applied. Additionally, HeLa cells were the most affected cells followed by HepG2, MCF-7, L929 and CACO-2, where the percentages of cell toxicity recorded were 76.1, 65.1, 59.5, 57.0 and 49.7%, respectively. Furthermore, the IC50 values obtained for MCF-7, HeLa and HepG2 cells were 226.1, 422.8 and 751.9 µg/mL, respectively. Conclusively, the present investigation provides preliminary results which suggest that seed essential oil from M. oleifera has potent cytotoxic activities against cancer cell lines.