A novel hybrid construction of MnMoO4 nanorods anchored graphene nanosheets; an efficient electrocatalyst for the picomolar detection of ecological pollutant ornidazole in water and urine samples.

Nitroimidazole compounds are widely used antibiotics to encounter anaerobic bacterial and parasitic infections. The wide usage of antibiotic drugs became an ecological contaminant which in turn into potential monitoring. In this regards, we have designed and developed a new electrochemical sensing probe to monitor an antiprotozoal drug, ornidazole (ODZ), with the aid of a glassy carbon electrode (GCE) integrated with manganese molybdate nanorods (MnMoO4) decorated graphene nanosheets (GNS) hybrid materials that prepared by feasible probe sonochemical method (parameters: 2-4 W, 5 mV amp, 20 kHz). The electrochemical investigations of the developed probe were performed by using rapid scan electrochemical workstations namely cyclic voltammetry (CV) and amperometric (i-t) techniques. The as-prepared MnMoO4/GNS nanocomposite was characterized and its purity of nanocomposite formation was confirmed by various analytical techniques like X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and Raman spectroscopy. In addition to that, the textural morphology of the MnMoO4/GNS nanocomposite was examined with the aid of field emission scanning electron microscopy (FE-SEM) and high-resolution transmission electron microscopy (HR-TEM). The MnMoO4/GNS nanocomposite rotating disk glassy carbon electrode (RDGCE) plays a crucial role in electrochemical detection of ODZ, which results in excellent anti-interference ability, a lower detection limit of 845 pM, massive linear ranges from 10 to 770 nM, and good sensitivity of about 104.62 µA µM-1 cm-2. From the acquired electrochemical studies, we have developed a disposable electrochemical sensor probe using a low-cost screen-printed carbon electrode (SPCE) with MnMoO4/GNS nanocomposite. The MnMoO4/GNS/SPCE are capably employed in real-time sensing of ODZ in water and urine samples. These electrochemical studies revealed the integral new vision on the electrocatalytic performance of the modified SPCE and also shown excellent amplification results in ultra-trace levels.

Tailoring of bismuth vanadate impregnated on molybdenum/graphene oxide sheets for sensitive detection of environmental pollutants 2, 4, 6 trichlorophenol.

In the present work, we reported a one pot simple colloidal-gel synthesis of molybdenum bismuth vanadate (MoBiVO4). The charge transfer property of MoBiVO4 was improved by developing a composite with graphene oxide (GO) through sonochemical technique. The optical and morphological analysis revealed that successful formation of GO-MoBiVO4 composite without any other filth. As prepared composite was used to modify the superficial surface of glassy carbon electrode (GO-MoBiVO4/GCE) and applied for the selective detection of environmental pollutant 2, 4, 6 trichrlorophenol (TCP). The electron channeling capability of GO with molybdenum bismuth vanadate possessed a superior electrochemical response in cyclic voltammetry (CV), whereas bare GCE and other modified electrodes provided an inferior response with lower current response. The differential pulse voltammetry (DPV) response of TCP at GO-MoBiVO4/GCE outcomes with low level detection of 0.4 nM and higher sensitivity of 2.49 µA µM-1 cm-2 with wider linear response 0.199-17.83 µM. Furthermore, the proposed sensor applied in practicability analysis and the results indicates GO-MoBiVO4/GCE prominent towards electrochemical detection of TCP.

Sonochemical synthesis of graphitic carbon nitrides-wrapped bimetal oxide nanoparticles hybrid materials and their electrocatalytic activity for xanthine electro-oxidation.

A novel network-like magnetic nanoparticle was fabricated on a graphitic carbon nitride through a facile sonochemical route at frequency 20 kHz and power 70 W. To enhance the electrocatalytic activity of the modified materials, the graphitic carbon nitrides (g-C3N4) was prepared from melamine. Monitoring of xanthine concentration level in biological fluids is more important for clinical diagnosis and medical applications. As modified CuFe2O4/g-C3N4 nanocomposite exhibits better electrochemical activity towards the oxidation of xanthine with higher anodic current compared to other modified and unmodified electrode for the detection of xanthine with larger linear range (0.03-695 µM) and lower limit of detection (13.2 nM). To compare with these methods, the electrochemical techniques may be an alternative high sensitive method due to their simplicity and rapid detection time. In addition, the practical feasibility of the sensor was inspected with biological samples, reveals the acceptable recovery of the sensor in real samples.

In Silico Elucidation of the Plausible Inhibitory Potential of Withaferin A of Withania Somnifera Medicinal Herb Against Breast Cancer Targeting Estrogen Receptor.

BACKGROUND: Estrogen Receptors (ER) are members of the nuclear intracellular receptors family. ER once activated by estrogen, it binds to DNA via translocating into the nucleus and regulates the activity of various genes. Withaferin A (WA) - an active compound of a medicinal plant Withania somnifera was reported to be a very effective anti-cancer agent and some of the recent studies has demonstrated that WA is capable of arresting the development of breast cancer via targeting estrogen receptor. OBJECTIVE: The present study is aimed at understanding the molecular level interactions of ER and Tamoxifen in comparison to Withaferin A using In-silico approaches with emphasis on Withaferin A binding capability with ER in presence of point mutations which are causing de novo drug resistance to existing drugs like Tamoxifen. METHODS: Molecular modeling and docking studies were performed for the Tamoxifen and Withaferin A with the Estrogen receptor. Molecular docking simulations of estrogen receptor in complex with Tamoxifen and Withaferin A were also performed. RESULTS: Amino acid residues, Glu353, Arg394 and Leu387 was observed as crucial for binding and stabilizing the protein-ligand complex in case of Tamoxifen and Withaferin-A. The potential of Withaferin A to overcome the drug resistance caused by the mutations in estrogen receptor to the existing drugs such as Tamoxifen was demonstrated. CONCLUSION: In-silico analysis has elucidated the binding mode and molecular level interactions which are expected to be of great help in further optimizing Withaferin A or design / discovery of future breast cancer inhibitors targeting estrogen receptor.

A novel triterpenoid 16-hydroxy betulinic acid isolated from Mikania cordata attributes multi-faced pharmacological activities.

The aerial parts of extensively used ethnomedicinal plant Mikania cordata (Burm. f.) Robinson growing wild in Bangladesh were investigated to isolate and characterize compounds responsible for the bioactivities of the plant. In the present study, a new derivatives of betulinic acid, 16-hydroxy betulinic acid [3ß,16-dihydroxy-lup-20(29)-en-28-oic] was isolated and the structure of the compound was determined by NMR spectroscopic means and comparing with available literature data. The isolated compound was then investigated for different pharmacological activities including antibacterial, antifungal, analgesic, anti-inflammatory and antipyretic potential employing different methods. The compound showed potent antibacterial activity with inhibition zone of diameter ranging from 12.0 to 17.5 mm and antifungal activity with mycelial growth inhibition ranging from 37.6 to 54.5%. The MIC values for antibacterial and antifungal activities ranged from 31.5-125 and 250-1000 µg/mL respectively. The compound (50 and 100 mg/kg body weight) showed potent peripheral and central analgesic activity with 55.19% and 41% of writhing inhibition at 90 min after administration of the compound and the highest 55.98%, 79.18% elongation of reaction time, respectively. In anti-inflammatory activity screening, the compound (100 mg/kg b.w.) revealed the highest 77.08% edema inhibition at 4 h after administration of carrageenan. In antipyretic assay, 16-hydroxy betulinic acid displayed a strong antipyretic effect in yeast-induced rats. From the present study it is apparent that 16-hydroxy betulinic acid might play vital role to establish M. cordata as ethnomedicinal plant to treat wound, cuts and fever.

Sonochemically recovered silver oxide nanoparticles from the wastewater of photo film processing units as an electrode material for supercapacitor and sensing of 2, 4, 6-trichlorophenol in agricultural soil samples.

The present work describes the sensing application and supercapacitive behavior of silver oxide nanoparticles recovered from wastewater of photo film processing units via one-pot green sonochemical recovery process. The recovered silver oxide nanoparticles (Ag2O NPs) were characterized by spectral techniques such as FT-IR, Raman, UV-Vis and analytical tools such as XRD, FE-SEM, TEM, EDX, XPS and BET. In view of Ag2O NPs as electrode material with wide technological applications, the recovered Ag2O NPs were examined for their sensing and supercapacitive behavior. The developed sensor was explored to detect 2, 4, 6-trichlorophenol, and as expected it shows moral parameters which are required of an effective sensor. Therefore, it was exploited for the quantification of 2, 4, 6-trichlorophenol in soil samples from the agricultural area. Cyclic voltammetric (CV), Galvanostatic Charge-Discharge (GCD) and Electrochemical Impedance Spectroscopic (EIS) studies on the recovered Ag2O NPs coated Ni foam electrode depicted the pronounced capacitive behavior. The GCD studies revealed an enhanced electrochemical performance, particularly with the large specific capacitance of 530 F/g at a current density of 1 A/g. The cyclic stability of the electrode material was identified with 88% retention in specific capacitance even after 5000 GCD cycles. These results strongly proved that the recovered Ag2O NPs are potential candidates for sensing and supercapacitor applications.

Sonochemical synthesis of bismuth(III) oxide decorated reduced graphene oxide nanocomposite for detection of hormone (epinephrine) in human and rat serum.

Herein, we report an efficient electrochemical sensor strategy for determination of epinephrine based on Bi2O3 nanoparticle decorated reduced graphene oxide nanocomposite (Bi2O3@RGO). The Bi2O3@RGO was prepared by simple ultrasonic method and then it's morphological and crystal structure aspects were well characterized by physiological instruments. The electrode-electrolyte interfacial properties were examined to ensure the catalytic ability of composite sensing towards EP. The composite was deposited on the multi-conventional screen-printed electrode and was found to be desirable performance toward EP oxidation. The amperometric EP sensing exhibited good reproducible and sensitive which able to detect as low as concentration of 2.14 nM. Furthermore, good reproducibility, long-term stability and repeatability were obtained from the electrode in experiment. Moreover, the EP sensing method was successfully applied in human and rat blood serum, the recoveries were validated by HPLC method. It indicates the reliability of the method in practical analysis.

Determination of the antioxidant propyl gallate in meat by using a screen-printed electrode modified with CoSe2 nanoparticles and reduced graphene oxide.

A voltammetric sensor is described for the quantitation of propyl gallate (PG). A screen-printed carbon electrode (SPCE) was modified with reduced graphene sheets that were decorated with cobalt diselenide nanoparticles (CoSe2@rGO). The material was hydrothermally prepared and characterized by several spectroscopic techniques. The modified SPCE displays excellent electrocatalytic ability towards PG. Differential pulse voltammetry, with a peak voltage at 0.34 V (vs. Ag/AgCl) has a sensitivity of 12.84 µA·µM-1·cm-2 and a detection limit as low as 16 nM. The method is reproducible, selective, and practical. This method was applied to the determination of PG in spiked meat samples, and the result showed an adequate recovery. Graphical abstract Schematic of a new method for fast and sensitive electrochemical determination of the food additive propyl gallate in meat.

Evaluation of anti-nociceptive, anti-inflammatory and antipyretic potential of Mikania cordata (Burm. f.) Robinson in experimental animal model.

Mikania cordata is widely used for the treatment of cuts, wounds, and dengue fever in Bangladesh. In the present study, essential oil (12.5, 25 and 50 mg/kg) and two extracts, viz., chloroform and ethyl acetate extracts (200, 400, 800 mg/kg b.w.) were tested for peripheral and central anti-nociceptive activity by acetic acid-induced writhing and hot plate method, respectively. Carrageenan-induced rat paw edema assay and yeast-induced hyperthermia assay were also carried out to evaluate anti-inflammatory and antipyretic properties of oil and extracts, respectively at aforesaid doses. The essential oil (50 mg/kg), chloroform extract (800 mg/kg) and ethyl acetate extract (800 mg/kg) showed potent peripheral anti-nociceptive activity having 47.33%, 29.33% and 16.65% of writhing inhibition, respectively, comparable with standard diclofenac (52.0%). Essential oil (50 mg/kg), chloroform extract (800 mg/kg) and ethyl acetate extract (800 mg/kg) presented promising central anti-nociceptive activity as well having 95.86%, 79.18% and 42.37% elongation of reaction time, respectively, at 90 min after administration of essential oil, ethyl acetate extract and 60 min after administration of chloroform extract. In anti-inflammatory activity screening, the essential oil (50 mg/kg) produced the highest 72.80% edema inhibition at 4 h after administration of carrageenan which was comparable with that of standard phenylbutazoe (87.87%). On the other hand, chloroform extract (800 mg/kg) and ethyl acetate extract (800 mg/kg) showed up to 34.31% and 15.27% of edema inhibition, respectively, at 4 h after administration of carrageenan. In antipyretic assay, the essential oil and chloroform extract displayed a strong antipyretic effect in yeast-induced rats, whereas the ethyl acetate extract had no antipyretic activity. The present study revealed anti-nociceptive, anti-inflammatory and antipyretic potential of M. cordata which could be the therapeutic option against fever, inflammations as well as painful conditions and confirmed the traditional use of M. cordata.

Detection of Pesticide Residues (Fenitrothion) in Fruit Samples Based On Niobium Carbide@Molybdenum Nanocomposite: An Electrocatalytic Approach.

We have reported an effective electrochemical sensor for assorted pesticide (i.e., Fenitrothion). Exact tracking of these pesticides has become more important for protecting the environment and food resources owing to their high toxicity. Hence, the development of compatible sensors for the real-time detection of pesticides is imperative to overcome practical limitations encountered in conventional methodologies. In this regard, the role of the novel, advanced functional materials such as niobium carbide (NbC) supported on molybdenum nanoparticles (NbC@Mo) has drawn great consideration in conventional sensory systems because of their numerous advantages over other nanomaterials. The nanocomposite was characterized by XRD, XPS, HR-TEM, and EIS. Under optimized working conditions, the modified electrode NbC@Mo/SPCE responds linearly as 0.01-1889 µM concentration range and the detection limit is 0.15 nM. Most importantly, the method was successfully demonstrated in fruit samples.

Synthesis and characterization of manganese diselenide nanoparticles (MnSeNPs): Determination of capsaicin by using MnSeNP-modified glassy carbon electrode.

A new type of manganese diselenide nanoparticles (MnSeNPs) was synthesized by using a hydrothermal method. Their surface morphology, crystallinity and elemental distribution were characterized by using transmission electron microscopy, X-ray diffraction, energy dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy which scrutinize the formation of the NPs. The NPs were coated on a glassy carbon electrode (GCE), and electrochemical impedance spectroscopy, cyclic voltammetry and differential pulse voltammetry were applied to study the electroanalytical properties towards the oxidation of the food additive capsaicin. The modified GCE displays lower charge transfer resistance (R ct = 29.52 Ω), a larger active surface area (0.089 cm2/g, and more efficient electrochemical oxidation of capsaicin compared to a MnS2/GCE and a bare GCE. The oxidation peak potential is 0.43 V (vs. Ag/AgCl) which is lower than that of previously reported GCEs. The sensor has a detection limit as low as 0.05 µM and an electrochemical sensitivity of 2.41 µA µM-1 cm-2. The method was applied to the determination of capsaicin in pepper samples. Graphical abstract Electrochemical determination of capsaicin in pepper extract by using MnSeNPs modified electrode.

Evaluation of traditional medicinal plant, Cissus setosa Roxb. (Vitaceae) for antiulcer property.

Cissus setosa is an indigenous medicinal herb commonly used for the treatment of gastro ulcers. In the current investigation the aerial methanolic extract of C. setosa was investigated for their antiulcer activity using pylorus ligation and ethanol in experimental rats. The extract was administered at the doses of 200 and 400 mg/kg b.w. orally for 3 days. However, higher dose of the extract subsequently reduced gastric ulcer induced aberrations by pylorus ligation (70.05%) and ethanol (78.16%) as judged by their altered biochemical parameters such as free acidity, total acidity, total carbohydrate, total protein and pepsin activity. Furthermore, macroscopic examination of rat's stomach also showed that the pretreatment with methanolic extract notably lowered the pylorus ligation and ethanol induced ulcers. As perceived in the present study, evidently, our findings basically supports the potency of the methanol extracts of C. setosa to treat gastrointestinal related disorders, thus lends pharmacological credence to the suggested folklore use.

Synthesis and application of bismuth ferrite nanosheets supported functionalized carbon nanofiber for enhanced electrochemical detection of toxic organic compound in water samples.

Recently, the multiferroic material has fabulous attention in numerous applications owing to its excellent electronic conductivity, unique mechanical property, and higher electrocatalytic activity, etc. In this paper, we reported that the synthesis of bismuth ferrite (BiFeO3) nanosheets integrated functionalized carbon nanofiber (BiFeO3 NS/F-CNF) nanocomposite using a simple hydrothermal technique. Herein, the structural changes and crystalline property of prepared BiFeO3 NS/F-CNF nanocomposite were characterized using Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). From this detailed structural evolution, the formation of nanosheets like BiFeO3 and its nanocomposite with F-CNF were scrutinized and reported. Furthermore, the as-prepared BiFeO3 NS/F-CNF nanocomposite modified glassy carbon electrode (GCE) was applied for electrochemical detection of catechol (CC). As expected, BiFeO3 NS/F-CNF/GCE shows excellent electrocatalytic activity as well as 3.44 (F-CNF/GCE) and 7.92 (BiFeO3 NS/GCE) fold higher electrochemical redox response for CC sensing. Moreover, the proposed sensor displays a wide linear range from 0.003 to 78.02 µM with a very low detection limit of 0.0015 µM. In addition, we have validated the real-time application of our developed CC sensor in different water samples.

One-pot synthesis of three-dimensional Mn3O4 microcubes for high-level sensitive detection of head and neck cancer drug nimorazole.

We described a three-dimensional Mn3O4 microcubes (3D-Mn3O4MCs) synthesised via a facile hydrothermal route for the determination of nimorazole (NMZ), an important drug that used in the treatment of head and neck cancer. The 3D-Mn3O4 MCs possess large active area and high conductivity, and 3D-Mn3O4 MCs film modified screen-printed carbon electrode (3D-Mn3O4MCs/SPCE) was fabricated which displayed excellent electrocatalytic ability towards NMZ. Under optimised working conditions, the modified electrode responded linearly to NMZ in the 0.025-8060µM concentration range and the detection limit was 6nM. A rapid, sensitive, selective, reproducible, and durable sensor was described. The practical feasibility of the sensor was demonstrated in human serum and NMZ tablet samples. The obtained results revealed the potential real-time applicability of the sensing device in biological analysis and pharmaceutical formulations.

Development of electrochemical sensor for the determination of palladium ions (Pd2+) using flexible screen printed un-modified carbon electrode.

To date, the development of different modified electrodes have received much attention in electrochemistry. The modified electrodes have some drawbacks such as high cost, difficult to handle and not eco friendly. Hence, we report an electrochemical sensor for the determination of palladium ions (Pd2+) using an un-modified screen printed carbon electrode has been developed for the first time, which are characterized and studied via scanning electron microscope and cyclic voltammetry. Prior to determination of Pd2+ ions, the operational conditions of un-modified SPCE was optimized using cyclic voltammetry and showed excellent electro-analytical behavior towards the determination of Pd2+ ions. Electrochemical determination of Pd2+ ions reveal that the un-modified electrode showed lower detection limit of 1.32µM with a linear ranging from 3 to 133.35µM towards the Pd2+ ions concentration via differential pulse voltammetry. The developed sensor also applied to the successfully determination of trace level Pd2+ ions in spiked water samples. In addition, the advantage of this type of electrode is simple, disposable and cost effective in electrochemical sensors.

A highly sensitive and selective electrochemical determination of non-steroidal prostate anti-cancer drug nilutamide based on f-MWCNT in tablet and human blood serum sample.

A novel electrochemical sensor based on the functionalized multiwalled carbon nanotube (f-MWCNT) was successfully developed for the sensitive and selective determination of non-steroidal prostate anti-cancer drug nilutamide in tablet and blood serum samples. The f-MWCNT was prepared by the simple reflux method and characterized by the scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), Raman spectroscopy, X-ray powder diffraction (XRD) and fourier transform infrared spectroscopy (FT-IR). Interestingly, the f-MWCNT was exhibited a superior electrocatalytic activity towards the anti-cancer drug nilutamide when compared with pristine MWCNT and unmodified electrodes. Besides, the electrochemical sensor was revealed an excellent current response for the determination of nilutamide with wide linear ranges (0.01-21µM and 28-535µM), high sensitivity (11.023 and 1.412µA µM-1cm2) and very low detection limit (LOD) 0.2nM. The developed electrochemical sensor was showed an excellent selectivity even in the presence of electrochemically active biological substances and nitro aromatic compounds. Moreover, it manifested a good reproducibility and stability. In addition, the f-MWCNT modified glassy carbon electrode (GCE) sensor was successfully applied for the detection of nilutamide in tablet and blood serum sample.

Antimicrobial efficacy of green synthesized drug blended silver nanoparticles against dental caries and periodontal disease causing microorganisms.

Development of biologically inspired green synthesis of silver nanoparticles is evolving into an important branch of nano-biotechnology. In the present investigation, we report the green synthesis of silver nanoparticles (AgNPs) employing the leaf extract of Justicia glauca. Water-soluble organics present in the leaf extract are mainly responsible for the reduction of silver nitrate (AgNO3) solution to AgNPs. The AgNPs are 10-20nm in dimensions as determined by TEM images. The antimicrobial activities of green synthesized AgNPs and drug blended AgNPs have been evaluated against the dental caries and periodontal disease causing microorganisms such as Streptococcus mutans, Staphylococcus aureus, Lactobacillus acidophilus, Micrococcus luteus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa and Candida albicans. The AgNPs and drug blended AgNPs show a significant antibacterial and antifungal activity. Minimum inhibitory concentration (MIC) value of AgNPs determined against the selected dental caries and periodontal disease causing microorganisms are noticeable between the range of 25-75µg/mL.

A simple electrochemical platform based on pectin stabilized gold nanoparticles for picomolar detection of biologically toxic amitrole.

Amitrole is a biologically toxic nonselective herbicide which contaminates surface and ground waters at unprecedented rates. All reported modified electrodes that detect amitrole within sub-micromolar to nanomolar levels were based on the electro-oxidation of amitrole. Herein, we developed a new conceptual idea to detect picomolar concentrations of amitrole based on calcium cross linked pectin stabilized gold nanoparticle (CCLP-GNP) film modified electrode which was prepared by electrodeposition. When the electrochemical behavior of amitrole was investigated at the CCLP-GNP film, the reduction peak current of the GNPs linearly decreased as the concentration of amitrole increases. We have designed a determination platform based on the amitrole dependent decrease of the GNP cathodic peak. The described concept and high sensitivity of square wave voltammetry together facilitate the great sensing ability; as a result the described approach is able to reach a low detection limit of 36 pM which surpassed the detection limits of existing protocols. The sensor presents a good ability to determine amitrole in two linear concentration ranges: (1) 100 pM-1500 pM with a detection limit of 36 pM; (2) 100 nM-1500 nM with a detection limit of 20 nM. The preparation of CCLP-GNPs is simple, rapid and does not require any reducing agents.

Palladium nanoparticles decorated on activated fullerene modified screen printed carbon electrode for enhanced electrochemical sensing of dopamine.

In the present work, an enhanced electrochemical sensor for dopamine (DA) was developed based on palladium nanoparticles decorated activated fullerene-C60 (AC60/PdNPs) composite modified screen printed carbon electrode (SPCE). The scanning electron microscopy and elemental analysis confirmed the formation of PdNPs on AC60. The fabricated AC60/PdNPs composite modified electrode exhibited an enhanced electrochemical response to DA with a lower oxidation potential than that of SPCE modified with PdNPs and C60, indicating the excellent electrooxidation behavior of the AC60/PdNPs composite modified electrode. The electrochemical studies confirmed that the electrooxidation of DA at the composite electrode is a diffusion controlled electrochemical process. The differential pulse voltammetry was employed for the determination of DA; under optimum conditions, the electrochemical oxidation signal of DA increased linearly at the AC60/PdNPs composite from 0.35 to 133.35 µM. The limit of detection was found as 0.056 µM with a sensitivity of 4.23 µA µM(-1) cm(-2). The good recovery of DA in the DA injection samples further revealed the good practicality of AC60/PdNPs modified electrode.

Enhanced electrocatalytic oxidation of isoniazid at electrochemically modified rhodium electrode for biological and pharmaceutical analysis.

A simple and sensitive electrochemical method has been proposed for the determination of isoniazid (INZ). For the first time, rhodium (Rh) modified glassy carbon electrode (GCE) has been employed for the determination of INZ by linear sweep voltammetry technique (LSV). Compared with the unmodified electrode, the proposed Rh modified electrode provides strong electrocatalytic activity toward INZ with significant enhancement in the anodic peak current. Scanning electron microscopy (SEM) and field emission scanning electron microscopy (FESEM) results reveal the morphology of Rh particles. With the advantages of wide linearity (70-1300µM), good sensitivity (0.139µAµM(-1)cm(-2)) and low detection limit (13µM), this proposed sensor holds great potential for the determination of INZ in real samples. The practicality of the proposed electrode for the detection of INZ in human urine and blood plasma samples has been successfully demonstrated using LSV technique. Through the determination of INZ in commercially available pharmaceutical tablets, the practical applicability of the proposed method has been validated. The recovery results are found to be in good agreement with the labeled amounts of INZ in tablets, thus showing its great potential for use in clinical and pharmaceutical analysis.