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Dodonaea (family Sapindaceae) - a genus of flowering plant (above 70 species recorded) and used for various activities. Dodonaea viscosa, D. angustifolia, D. spatulate, D. polyandra and D. ceratocarpa are well-known species of this genus. In spite of the possible health support, different plant species from this genus are not extensively noticed in the modern medicine system. Dodonaea genus has been traditionally used in the treatment of scurvy, inflammation, kidney pain, sore throat, intestinal parasite, herpes, wounds burn, rheumatism, cough, backache, toothache, skin burn, skin infection, tumor and wound healing. Plant leaves, stem and fruits are occasionally used in the formulation of traditional medicine. In terms of phytoconstituents, flavonoids, flavones and their derivatives, terpenoids and saponins are major isolated compounds. They have shown antimicrobial, antioxidant, anti-inflammatory, antidiabetic, hepatoprotective and anti-plasmodial activities. Plants of Dodonaea genus show insecticide, weedicide, pesticide activity and exhibit allelopathic effect. Further, some isolated bacteria from roots of D. viscosa have been used in other plants as a plant growth-promoting rhizobacteria. Additionally, leaf extract has also been used in nanoparticle synthesis. These particles have shown a significant antioxidant activity; and antibacterial activity towards both gram positive and gram negative bacteria. Overall, this review paper aims to describe the different aspects of Dodonaea genus such as botanical description, ethnomedicinal uses, phytochemistry, pharmacological and agricultural applications of Dodonaea genus. Besides, some other miscellaneous studies and applications have been also reviewed.

Fruits and vegetables are an important part of a healthy diet. In this regard, Carica papaya (papaya) is one of them, a native to Mexico and northern South America, now naturalized in many parts of the world including tropical and subtropical regions. The papaya fruit pulp is rich in minerals and many vitamins, while seed contains glucosinolates, tocopherols, carotenoids, and benzyl isothiocyanate. Papaya is known for numerous activities such as antioxidant, antibacterial, anticancer activity, anti-fertility agent, anti-inflammatory, antiulcer, antidiabetic, hepatoprotective, and many more due to the presence of phenolics, flavonoids, and alkaloids as the key phytochemicals. Many commercial products obtained from different plant parts are available in the market and are being utilized for various purposes. More specifically, papaya fruit is used to produce a large number of processed foods such as jam, jelly, pickle, candied fruit, puree, concentrate, and canned slices/chunks. Fruit peels find its application in cosmetics, in wastewater treatment, as animal feed, and as a binder in ceramics. Papaya leaf, bark, root, and seeds have also shown the insecticidal and repellent activities. More interestingly, in the recent past, papaya and different parts are used for nanoparticle synthesis which has shown numerous applications. This review mainly focuses on the various phytochemicals present in different parts of plant C. papaya, their pharmacological activities, and several other applications. For writing this review paper, a literature survey was carried out via classic books of medicinal and fruit plants. Online scientific databases, for instance, PubMed, Scopus, Sci Finder, Science Direct, the Web of Science, Wiley Online, Google Scholar, ResearchGate, and other search engines were explored up to October 2020 to detect valid reports, studies, and investigations. All literature on the proposed topics were analyzed and summarized in this review paper.

The electrochemical determination of prednisolone has been investigated at fullerene-C(60)-modified gold (C(60)/Au) electrode and gold nanoparticles modified indium tin oxide (nano Au/ITO) electrode in phosphate buffer solution (PBS) of pH 7.2. During oxidation of prednisolone, an anodic peak with peak potential (E(p)) at 570 mV and 400 mV appeared at nano Au/ITO and C(60)/Au electrode, respectively. The experimental results revealed that gold nanoparticles as well as fullerene (C(60)) promote the rate of prednisolone oxidation by increasing the peak current (i(p)) and oxidizing at lower peak potentials as compared to the respective bare electrodes due to their electrocatalytic effect. The linear concentration range at both the electrodes was in the range of 1 microM to 0.10 mM. The detection limit obtained at C(60)/Au electrode was 26 nM, while at nano Au/ITO electrode the detection limit was 90 nM. The applicability of the method to direct assays of human urine and whole blood sample is described to use the method for testing cases of doping by athletes.

The electrochemistry of bisoprolol fumarate (BF) has been investigated by differential pulse voltammetry at a single-wall carbon nanotubes (SWNTs) modified glassy carbon electrode (GCE). The prepared electrode showed an excellent electrocatalytic activity towards the oxidation of BF leading to a marked improvement in sensitivity as compared to bare glassy carbon electrode where electrochemical activity for the analyte cannot be observed. The SWNTs-modified GCE exhibited a sharp anodic peak at a potential of ∼950 mV for the oxidation of BF. Under optimum conditions linear calibration curve was obtained over the BF concentration range 0.01–0.1 mM in 0.5 M phosphate buffer solution (pH 7.2) with a correlation coefficient of 0.9789 and detection limit of 8.27 × 10−7 M. The modified electrode has been applied for the drug determination in human urine with no prior extraction and in commercial tablets. The proposed method has also been validated.

The electrochemical behaviour of nandrolone is investigated by cyclic, differential pulse and square-wave voltammetry in phosphate buffer system at fullerene-C 60 -modified electrode. The modified electrode shows an excellent electrocatalytic activity towards the oxidation of nandrolone resulting in a marked lowering in the peak potential and considerable improvement of the peak current as compared to the electrochemical activity at the bare glassy carbon electrode. The oxidation process is shown to be irreversible and diffusion-controlled. A linear range of 50 μM to 0.1 nM is obtained along with a detection limit and sensitivity of 0.42 nM and 0.358 nA nM −1 , respectively, in square-wave voltammetric technique. A diffusion coefficient of 4.13 × 10 −8 cm 2 s −1 was found for nandrolone using chronoamperometry. The effect of interferents, stability and reproducibility of the proposed method were also studied. The described method was successfully employed for the determination of nandrolone in human serum and urine samples. A cross-validation of observed results by GC–MS indicates that the results are in good agreement with each other.

Nickel(II)-selective sensors have been fabricated from poly(vinyl chloride) (PVC) matrix membranes containing neutral carrier dibenzo-18-crown-6 as electroactive material, sodium tetraphenylborate (NaTPB) as an anion excluder and tris-(2-ethylhexyl) phosphate (TEHP) as plasticizing solvent mediator. The membrane having the composition of crown ether:NaTPB:TEHP:PVC in the ratio 10:1:200:200 (w/w) exhibits best results with linear potential response in the concentration range of 1.0x10(-5) to 1.0x10(-1)M and a Nernstian slope of 29.5mV/decade of activity between 2.6 and 6.8. The sensor exhibits a fast response time of25s, is inert towards non-aqueous medium up to 15% (v/v) and was used over a period of 4 months with good reproducibility. It is selective over a number of mono-, bi- and trivalent cations. The practical utility of the sensor has been demonstrated by using it as an indicator electrode in the potentiometric titration of Ni(2+) against EDTA and also for the estimation of Ni(2+) in some Indian brand chocolates.

Poly(vinyl chloride) (PVC) based membranes containing 4- tert -butylcalix[4]arene (I) as an electroactive material alongwith anion excluder sodiumtetraphenylborate (NaTPB) and plasticizer tri-butylphosphate (TBP) have been developed to fabricate a new zinc-selective sensor. Out of various compositions, the best performance was exhibited by the membrane having I, NaTPB, TBP and PVC in the ratio 8:5:100:200 (w/w). The sensor works well in the concentration range 9.8 × 10 −6 to 1.0 × 10 −1 mol dm −3 with a near-Nernstian slope of 28.0 ± 1.0 mV/decade of activity. The detection limit is down to 5.0 × 10 −7 mol dm −3 . The working pH range of this sensor is 2.5–4.3 and it works well in partially non-aqueous medium up to 15% (v/v) (methanol, ethanol and acetone). It exhibits a fast response time of 30 s and could be used for more than four months without any considerable change in response characteristics. It has excellent selectivity for Zn(II) over other mono-, bi- and trivalent cations which have been reported to cause interference in the working of other sensors. It has been successfully used as an indicator electrode in the potentiometric titration of Zn(II) against EDTA and also to estimate zinc ions in industrial waste waters.

A nanogold modified indium tin oxide (ITO) electrode was used for the determination of paracetamol at pH 7.2. The electrode exhibited an effective catalytic response to the oxidation of paracetamol with good reproducibility and stability. Under conditions of differential pulse voltammetry, the oxidation potential of paracetamol is lowered by approximately 110 mV and current response is enhanced significantly relative to the situation prevailing when a bare ITO electrode is used. Linear calibration curve is obtained over the range 2.0 × 10−7–1.5 × 10−3 M with a correlation coefficient of 0.997. The detection limit (3σ) was estimated to be 1.8 × 10−7 M. The physiologically common interferents viz., ascorbic acid, glucose and urea negligibly affected the current response of paracetamol. The practical analytical utility of the method is illustrated by determination of paracetamol in pharmaceutical preparations. Keywords: Nanogold modified indium tin oxide electrode, Paracetamol, Differential pulse voltammetry, Pharmaceutical preparations