Selective Electrode Research Articles

Behavior of a forest of NiFe nanowires in KOH and NaCl solution for water electrolysis

The present work investigates the behavior of nanostructured electrodes consisting of an array of nanowires of NiFe alloy in KOH + 0.5 M NaCl solution. The aim is to explore the possibility of using these electrodes for hydrogen production by seawater electrolysis. Seawater splitting requires a highly selective electrode on the anode side, where the evolution of molecular chlorine or the formation of other active chlorine compounds can compete with the oxygen evolution reaction. Nanostructured electrodes, obtained by template electrosynthesis, were tested at room temperature in KOH + 0.5 M NaCl solution, and the results were compared with those obtained in pure KOH. The results showed that the presence of NaCl does not affect the electrocatalytic behavior of the nanostructured NiFe alloy. Furthermore, the chemical–physical characterizations carried out after the long-term galvanostatic tests, have shown that the nanostructured electrodes are also stable in terms of morphology and composition. In addition, the solution used to perform the long-term galvanostatic tests was analyzed to investigate the possible formation of chlorine compounds. The absence of these compounds, together with the measured potential value measured for the oxygen evolution reaction, which was always lower than the thermodynamic redox potential for the hypochlorite formation reaction, leads us to conclude that these electrodes are potentially suitable for seawater electrolysis.

Comparative Evaluation of Fluoride Release from Four Commercially Available Pediatric Dental Restorative Materials.

The aim of this study was to evaluate the fluoride-releasing abilities of commercially available restorative materials such as-Activa™ BioActive-restorative™ material, Zirconomer (Shofu Inc), Beautifil® II (Shofu Inc), GC Gold Label 9 high strength posterior restorative glass ionomer cement (GIC Corp). A total of 40 disk specimens (10 of each material) were placed into distilled/deionized (DI) water and the fluoride release was measured for 30 days. Fluoride ion measurement was performed at the end of the 1st, 3rd, 7th, 15th, and 30th day under normal atmospheric conditions by fluoride ion selective electrode (F-ISE) (Orion 9609 BNWP, Ionplus SureFlow fluoride electrode, Thermo Scientific, United States of America) coupled to a benchtop analyzer (Hachsen Ion+). All the materials included in the study exhibited fluoride release. Although there were differences in the amounts of fluoride released between Activa™, Zirconomer, and GC Gold Label 9 the mean difference between these three groups was not found to be statistically significant. Beautifil® II showed low amounts of fluoride released at all time intervals. Among the above-compared materials Activa™ and Zirconomer exhibit both improved mechanical properties as well as they have fluoride-releasing ability so can be preferred over conventional glass ionomer restorations. Dhumal RS, Chauhan RS, Patil V, et al. Comparative Evaluation of Fluoride Release from Four Commercially Available Pediatric Dental Restorative Materials. Int J Clin Pediatr Dent 2023;16(S-1):S6-S12.

Celeriac as ionphore for green Co+2 selective PVC membrane electrode by experimental and theoretical investigation

Environmental pollution of heavy metals is increasingly becoming a problem and has become of great concern due to the adverse effects it is causing around the world. Many techniques were applied to detect, to determine and to remove. In this study, a simple electrochemical methods was used. The preparation of a novel PVC membrane green sensor was conducted for the Co+2 ion considering the Celeriac alcoholic extract. The sensor has a 29.5 mV decade−1 Nernstian slope within an extensive range of linear concentrations from 0.38 × 10−3 to 0.08 × 10−3 while possessing a 0.03 × 10−4. M detection limit. The response time reported for the proposed sensor is < 10 s, and it is useable for a minimum period of one month with no significant potential divergence. The potentiometric response independence from the test solution pH was also confirmed at pH ranges of 5.8–11. The introduced electrode is appropriately selective in various transition metal ions. The reactivity (chemical and electromechanical) characteristics, including electronegativity, electrophilicity, chemical potential, band gap, softness, and hardness were calculated using the DFT technique. As shown by the results, the apijin was highly reactive in different Celeriac compounds.

Development of Wearable Microneedle-Based Platform for Real-Time Biomarkers Sensing

The wearable device technology plays a huge role in the healthcare sector owing to the aging global population and increased acquisition of the internet of things (IoT). Further, the Coronavirus Disease-2019 (COVID-19) pandemic has accelerated the emergence of wearable medical devices in the market. The patients with chronic diseases are more focused on tracking single or multiple nutrients and biomarkers in the body. Diabetes is a classic example of chronic disease where the patients need to monitor their blood glucose level for a long time. In addition, diabetic patients also face electrolyte imbalance which gives rise to several other diseases. There is an immense urgency to develop a sensing platform that can detect the essential ions as well as biomarkers from the interstitial fluid (ISF) as it contains valuable information about the physiological status of a person. According to Centers for Disease Control and Prevention (CDC), imbalance of sodium concentration in the body may lead to stroke, hypertension, and epilepsy; for potassium: arrhythmia, chronic kidney disease (CKD), and dizziness; for calcium: depression, osteoporosis, and other bone-related disease; for pH of body fluid: urinary tract infection, respiratory acidosis, and sleep apnea. Within this advent of wearables, microneedle (MN)-based transdermal sensors are well positioned to play a key role in combining the significant benefits of dermal interstitial fluid (ISF) as a source of clinical indicators and minimally invasive skin puncturing to allow the collection of real-time diagnostic data. In this context, we have developed a MNs based versatile platform for the transdermal amperometric detection of glucose and different clinically relevant biomarkers such as K+, Na+, Ca2+ in the body fluid in a robust, reliable, and cost-effective way. Here, stainless steel microneedle (SS-MN) is used as an ideal candidate for multiplex sensing due to its great chemical stability as well as the rigidity for accurate and painless puncture. The device is fabricated with ion selective electrode (ISM) coating on each needle for their corresponding electrolyte and enzyme for glucose detection. In vitro experiments performed in artificial ISF samples yielded excellent sensitivity and a good linear response. The sensor is successfully applied for in vivo detection of glucose and these ions in SD rats for validating their feasibility as a real-time sensing device. Overall, this developed concept comprises of significant progress in the sensing of glucose and other ions in relation to an electrolyte imbalance in the humans that holds relevance in controlling several diseases.

Effect of Electrode Spacing on the Detection of Coating Defects in Buried Pipelines Using Direct Current Voltage Gradient Method

Buried piping is subject to soil corrosion, which can be prevented by combining coatings and cathodic protection to maximize corrosion control. However, even with both methods, coatings are subject to damage from external factors and various causes. Buried piping may expose the metal and alter the current flow, which in turn causes corrosion. Therefore, this study analyzed the effect of detection electrode spacing on the direct current voltage gradient (DCVG) magnitude formed for coated pipelines buried in the soil. The DCVG was measured using a real-time coating defect detection system. FEM model simulations were carried out, and then the result was compared to the measured DCVG magnitude. When the spacing of the detection electrodes increased, the detected signal and signal location changed. The detection reliability increased as the noise signal is eliminated at the optimum detection electrode spacing. However, the detection reliability decreased at higher selection electrode spacing as the noise signal and detected signals together were eliminated. The location of the detected signal shifted as the spacing of the detection electrodes increased due to the change in the detection reference point and signal magnitude.

In-situ synthesis of bi-metallic metal organic Framework/Polyaniline nanocomposites as ultrasensitive and selective electrodes for electrochemical detection of heavy metal ions

Due to the toxicity of heavy metal ions which impacts on public health and the environment, the development of effective methods of detection has assumed a high priority. In this study, we have established an electrochemical sensor based on a CoCu-MOF/polyaniline (CoCu-MOF/PANI) sensing electrode that can simultaneously detect Pb2+ and Cd2+ in water samples. The CoCu-MOF/PANI composite was prepared by a one-step in situ polymerization method and characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). The Pb2+ and Cd2+ content was detected by differential pulse voltammetry (DPV) at an optimized pH (4.5). The proposed electrochemical sensor has achieved simultaneous Pb2+ and Cd2+ detection down to 0.39 ug/L (Pb2+) and 0.61 ug/L (Cd2+). Anti-interference and reproducibility experiments have been conducted. In spiking experiments, the recovery of Pb2+ and Cd2+ in water samples ranged from 98.6% to 102.13%, indicating effective targeted electrochemical sensing. This work has delivered a functional design of CoCu-MOF/PANI materials, and established an efficient methodology for heavy metal ion detection.

A Comparative Study of Serum Sodium and Potassium Levels across the Three Trimesters of Pregnancy

Aim: To evaluate the serum sodium and potassium levels in the three trimesters of pregnancy in women. Methods: Four groups of healthy women between the ages of 20 and 30 years, volunteered for this study. Group 1: Non-pregnant women (control), Group 2: Pregnant women in their first trimester, Group 3: Pregnant women in their second trimester, Group 4: Pregnant women in their third trimester. Blood samples were collected by standard aseptic method and serum samples were analyzed for serum levels of sodium and potassium by the ion selective electrode method. Results were presented as MEAN ± SEM in tables and figures, p &lt; 0.05 was regarded as statistically significant. Results: The serum sodium concentrations in mmol/L were 135.3 ± 3.09, 136.3 ± 1.55, 139.0 ± 0.78, 139.8 ± 0.91 for control, first-trimester, second-trimester, and third-trimester subjects respectively. The potassium concentrations in mmol/L were 3.678 ± 0.26, 3.687 ± 0.13, 3.820 ± 0.11, 3.767 ± 0.07 for control, first-trimester, second trimester and third-trimester subjects respectively. The Bodyweight values in kg were 72.13 ± 2.11, 74.73 ± 2.05, 75.00 ± 1.72, 81.56 ± 4.24 for control, first-trimest, second-trimester, and third-trimester subjects respectively. Conclusion: Results indicate that the hormones of pregnancy altered the body weight of pregnant women, but did not change the serum sodium and potassium level across the three trimesters of pregnancy in women. This is an indication that the kidneys of healthy pregnant women can handle serum electrolyte load during the period of pregnancy.

Ni3S2/Co9S8 directly grown on nickel foam as an environmentally friendly electrocatalyst for seawater splitting

Seawater is one of the most abundant sources of hydrogen on Earth, so its decomposition for producing hydrogen has a significant advantage. However, because of the presence of high concentration of chloride ion (Cl−) in seawater, it has corrosive effect on the catalyst. Therefore, the exploration and construction of highly robust anticorrosive OER electrocatalyst were studied. Furthermore, this work describes Co9S8@Ni3S2/NF as a catalyst, which provides a current density of 100 mA cm−2 with a required overpotential of only 154 mV, with emphasis on their remarkable OER selectivity. The experimental analysis demonstrate that the promotion of Co9S8@Ni3S2/NF catalyst activity can be attributed to the construction of heterogeneous interface, the rapid transfer of charge and the exposure of more reaction centers. Density functional theory analysis demonstrates that the Co9S8 material presents greater water adsorption energy, indicating that water preferentially adsorbs on its surface. The introduction of the Ni3S2 electrode greatly promotes the synergistic effect of the Co9S8@Ni3S2/NF electrode. It is the synergistic catalysis of these two electrodes that enhances the catalytic activity and selectivity of the materials. The work furnishes a novel idea for the exploration of efficient, environmentally friendly and highly selective electrodes for seawater splitting.

Green Prospective Approach of Chromium Zinc Oxide Nanoparticles for Highly Ultrasensitive Electrochemical Detection of Anti-hypotensive Medication in Various Matrices.

A highly ultrasensitive sensor that relied on Cr/ZnO-NPs was developed to detect etilefrine hydrochloride (ETF) in different matrices via a particular green voltammetric technique. The X-ray diffraction pattern showed the nanomaterials of the polycrystalline hexagonal structure. The energy-dispersive X-ray spectrum approved the presence of Cr3+ inside the host zinc oxide framework. The morphological and topological characteristics were visualized using transmission electron microscopy and atomic force microscopy micrographs describing the nanoparticles in spherical-like shape with large-surface area. The energy gap (Eg) was evaluated from transmittance (T %) and reflectance (R %) spectra within the visible region. The optimization study indicated that the Cr/ZnO-NP/CPE sensor has high sensitivity, thanks to the distinctive physical and chemical properties of the fabricated electrode. A new approach showed a great selectivity for determining ETF in different matrices in the presence of other interferents like levodopa. Under optimal circumstances, the square-wave voltammetry revealed a linear response to ETF from 0.01 to 10 μmol L-1 (r = 0.9996) with quantification and detection limits of 9.11 and 2.97 nmol L-1, respectively. Finally, the proposed approach was effectively applied to estimate ETF in pharmaceutical dosage forms and biological fluids using simple, accurate, and selective electrochemical electrode. The greenness profile assessment of the developed method was performed using the Eco-Scale and green analytical procedure index. These tools indicated that the proposed method is an eco-friendly technique for the determination of ETF in different matrices.

Separation of fluoride in the presence of large amounts of organic acids by ion chromatography

ABSTRACT An ion chromatography (IC) method for the separation of fluoride in presence of large concentrations of organic acid anions was developed with a view to determine trace level concentration of fluoride in plant samples. Present study deals with determination of fluoride in dry black gram seeds. Pyrohydrolysis was employed for extracting fluoride from the seeds. Organic acid anions are produced during pyrohydrolysis of seeds/plant materials and these organic anions show similar retention behavior of fluoride in IC. Separation of fluoride from organic acids and common anions was investigated. An IC method involving the appropriate dilution of pyrohydrolysis distillate of the sample followed by a large volume injection through a pre-concentrator column is proposed to circumvent the interference due to organic acids. Fluoride recovery of the pre-concentrator column is found to be more than 90%. The method provides a precision better than 7% (RSD). The limit of detection of the method is 0.5ppmw whereas the LOD for fluoride by IC method alone is 10 ppb. Results obtained are validated by analyzing the samples by using fluoride ion selective electrode method.

Targeted electro-redox facilitating efficient delithiation of lithium manganese ion-sieve selective electrode

The electrically switched ion exchange (ESIX), as the most promising technique for the efficient extraction of lithium from brine, especially the lithium manganese ion-sieve membrane electrode, possesses the advantages of high selectivity, high adsorption capacity, and high stability. And to enable the simultaneous lithium intercalation and de-intercalation at the cathode and anode, respectively, the selective electrode ought to be delithiated before use. Traditional chemical and electrochemical delithiation and electrochemical techniques consume enormous amounts of reagents and energy, respectively. Thermodynamics and electrochemical analysis indicated that the cathodic reaction induced the high cell voltage, which in turn caused the emitting of toxic gases and high energy consumption. Thus, in this study, a targeted-redox system was adopted to alleviate the above problems. By adding excessive Cu2+ into the cathode compartment, the cell voltages in 5 h reduced from 3 V to about 1.5 V and further reduced to 1.2 V if diluted HCl was also added. With lower cell voltage and higher current density, a higher delithiation rate can be reached (95.83 %). Furthermore, Cu2+ can be regenerated by bubbling O2 under an acidic atmosphere, which enables the re-utilization of the cathodic solution. The targeted electro-redox system can reduce 2980.49 J of the energy consumption compared with the current electrochemical delithiation method, meanwhile, the utilization of cheaper counter electrode makes it economically viable.

Interface‐Targeting Individually Functionalized Ionic Additive to Construct Stable Interphase on Selective Electrode Surface for Practical Lithium‐Ion Pouch Cells

AbstractIndividually functionalized cation‐ and anion‐based ionic additives are designed to mitigate the interfacial side reaction occurring on both the positive and negative electrode surfaces. By applying 1‐phenyl‐1H‐imidazole‐3‐ium trifluoromethanesulfonate as a surface‐targeting electrolyte additive, the reciprocal failure from multiple electrolyte addition applications is theoretically prevented. Selective interface modification is performed using ionic additives by the migration of cations and anions to the negative and positive electrode surfaces, respectively. A drastic improvement in cycleability compared with that by a general carbonate electrolyte is achieved because the reinforcement of both the graphite and LiNi0.8Co0.1Mn0.1O2 electrode surface is possible by ionic additives. Moreover, a further improvement in the cycle performance compared with that by the typical solid electrolyte interphase‐forming additives, such as vinylene carbonate and fluoroethylene carbonate, is demonstrated by the ionic additive.

A green compliant hand-held selective electrode device for monitoring active pharmaceuticals and the kinetics of their degradation

An in-line smartphone connected to a screen-printed selective electrode hand-held device was used to determine the concentration of distigmine bromide (DB) in its pure and dosage forms as well as its degradation kinetics by continuously measuring the change in the produced emf over time. The main objective, supported by the data presented, is to produce a highly reliable smartphone integrated selective sensor as a portable analyzer with potential high cloud connectivity combining a wide linear dynamic range, the fastest response time with the lowest limits of detection and quantitation while best integrating green analytical chemistry principles. The choice of ionophore used in this approach was guided by computation and the data obtained was compared with traditional analytical techniques. DB, for which there are no previously reported stability-indicating methods and for which four novel such methods are proposed here, was selected as a model drug for this work. At-line UV-spectrophotometry DB assay was obtained by measuring the difference between the spectra of the degradation product and the same concentration of intact drug. The degradation kinetics were studied by this method through tracking the decrease of DB absorbance and/or the increase of a generated degradation product signal over time. Off-line separation based HPLC and TLC stability-indicating methods for DB were also presented. All methods employed in this work were validated for accuracy, precision, specificity, repeatability, linearity, range, detection and quantification limits according to the ICH guidelines and were applied to the analysis of laboratory prepared mixtures as well as commercial products. While all methods proposed were shown to be highly reliable, the smartphone integrated selective sensor is highlighted as a portable analyzer with potential high cloud connectivity and was shown to combine a wide linear dynamic range, the fastest response time with the lowest limits of detection and quantitation while best integrating green analytical chemistry principles.

Synthesis and Characterization Graphene- Carbon Nitride Nanostructure in One Step

Graphene-carbon nitride can be synthesized from thiourea in a single step at a temperature of four hours at a rate of 2.3 ℃/min. Graphene-carbon nitride was characterized by Fourier-transform infrared spectroscopy (FTIR), energy dispersive X-ray analysis (EDX), scanning electron microscopy, and spectrophotometry (UV-VIS). Graphene-carbon nitride was found to consist of triazine and heptazine structures, carbon, and nitrogen. The weight percentage of carbon and the atomic percentage of carbon are 40.08%, and the weight percentage of nitrogen and the atomic percentage of nitrogen are 40.08%. Therefore, the ratio and the dimensions of the graphene-carbon nitride were characterized by scanning electron microscopy, and it was found that the radius was within the range of (2 µm-147.1 nm). In addition, it was found that it absorbed light in the visible field (VIS). The objective of the manufacture and characterization of graphene-carbon nitride for use in the manufacture of a selective electrode for an organic pollutant (currently used in the manufacture of a selective electrode for the analysis of organic dye).

On-hand tool for ammonium and urea determination in saliva to monitor chronic kidney disease – Design of a couple of microfluidic paper-based devices

In this work, two microfluidic paper-based analytical devices (μPADs) were developed for the quantification of urea and NHx in human saliva to aid in the diagnosis/monitoring of chronic kidney disease (CKD). The NHx determination was based on the conversion of ammonium to ammonia, followed by its diffusion through a hydrophobic membrane and then the color change of bromothymol blue (BTB) indicator. In the urea determination, prior to the ammonium conversion and BTB color change, the enzymatic conversion of urea into ammonium was produced, using urease. Several optimization studies were carried out to attain a quantification range of 0.10–5.0 mM with 0.032 mM limit of detection for the NHx μPAD, and a determination range of 0.16–5.0 mM with 0.049 mM limit of detection for the urea μPAD. The method accuracy was assessed, and the measurements obtained with NHx μPAD were compared with the ones obtained from an ammonia ion selective electrode; while the measurements of the urea μPAD were compared with the ones obtained from a commercially available kit. There were no statistically significant differences between methods, proving that both NHx and urea μPAD were effective on-hand tools for CKD monitoring in saliva. To evaluate their functionality as point-of-care devices, stability studies were also performed and revealed that both NHx and urea μPAD were stable when stored in a vacuum for 2 and 1 month, respectively. After the sample introduction, the NHx μPAD could be scanned within the first 2 h and the urea μPAD within 1 h.

A comparison of serum sodium levels measured using a colorimetric kit approach and those determined using direct and indirect ion selective electrode techniques- in a Hospital Central Lab

When electrolyte imbalances are not recognized, they are known to cause severe morbidity and mortality. Dyselectrolytemia is frequently curable. Hyponatremia is a common symptom seen in the elderly. Laboratory equipment may be lacking in rural healthcare settings. As a result, the purpose of this study was to investigate the feasibility of developing a screening technique that can aid in the detection of hyponatremia in such facilities. Serum sodium levels in 120 samples were determined by direct, indirect, and colorimetric ISE. SPSS version 17, NCSS 11, and MINITAB 18 software were used for statistical analysis. Statistical significance was defined as a p-value of 0.05. While comparing the instruments, a basic linear regression analysis was performed, and a regression equation for sodium levels was established. The Bland-Altman analysis yielded a 95% agreement limit between the instruments, which is well within the CLIA-recommended target value of 4 mmol/L in the hyponatremic and normonatremic ranges. The resulting regression equation computes a predicted value for direct and indirect ISE using the colorimeter readings, making it similar to all three instruments in the hyponatremic and normonatremic ranges. The colorimetric method can be used as a low-cost screening technique to identify hyponatremic elderly people for whom a tertiary hospital may be inaccessible, allowing for early care.

Plastic antibodies integrated with graphene quantum dots for electrochemical sensing of bisphenol-A in real samples

Bisphenol-A (BPA) is a hazardous chemical used in plastic manufacturing units. BPA is recognized as an endocrine disruptor that can act as environmental estrogen and affect the activity of natural endogenous hormones. BPA is both genotoxic and cytotoxic; hence, developing a sensor for its recognition and quantification is essential. In this study, a molecularly imprinted polymer (MIP) based electrochemical sensor was developed for the analysis of Bisphenol-A (BPA). The fabrication of BPA/PEDOT/GQDs/AuNPs/GCE was carried out by electrodepositing the gold (Au) nanoparticles followed by electropolymerization employing 3,4-ethylenedioxythiophene (EDOT) and in-situ graphene quantum dots (GQDs). The characterization was performed using numerous techniques such as FESEM, XRD, UV–vis, TEM, FTIR, and electrochemical techniques. The linear range for the detection of Bisphenol-A was 1 nM to 50 µM with a low detection limit (LOD) of 0.19 nM and a limit of quantification (LOQ) of 0.64 nM. The proposed method delivered selective, sensitive, and reusable electrodes for the detection of BPA. The recovery was found to be 95–112% and the fabricated electrode was successfully utilized for the analysis of BPA in the real samples.

Design of Solid-contact Ion-selective Electrode with Multiwall-carbon Nanotubes for Assay of Sulfacetamide in Rabbit Aqueous Humour

Background: Inclusion of multiwall-carbon nanotubes (MWCNTs) as ion-to-electron transducers within the ionophore-doped PVC membrane has a great impact on the stability and robustness of the produced sensor performance compared to conventional liquid-based ISEs. Objective: Solid-contact ion selective electrodes (SC-ISEs) were fabricated and optimized for the assay of sulfacetamide sodium in both ophthalmic eye drops and in rabbit aqueous humor. Methods: 2-hydroxypropyl-β-cyclodextrin (2HP-β-CD) was selected as an ionophore to dope the ionselective membrane to enhance its selectivity towards sulfacetamide. The performance of multiwall-CNTs as ion-to-electron transducer was evaluated by comparing MWCNT-based SC-ISE with control sensor which does not include the MWCNTs. The electrochemical performance characteristics of the proposed sensors were assessed in accordance with the IUPAC recommendations. A green profile assessment of the proposed method was performed using Eco-Scale and AGREES metrics. Results: Inclusion of MWCNT into the sensing membrane improved the performance of the developed sensor. The linearity range was (2.5 x 10-4 M - 1.0 x 10-2 M) for both sensors and the LOD was estimated to be 5.6 x 10-5 M for GCE/ISM(CNT) and 1.5x 10-4 M for control sensor GCE/ISM. The results of green assessment for both the developed and the official method showed an excellent greenness of the proposed method. Conclusion: The proposed sensor can be applied successfully for the determination of sulfacetamide in eye drops and rabbit aqueous humour.

Plasticizer-free Hydrazonic Dibenzo-18-crown-6 derived lead ion sensing electrodes

The redox behaviours of three dibenzo-18-crown-6 hydrazones were investigated via cyclic and square wave voltammetries, prior to their electropolymerization onto a platinum working electrode to yield three novel Ion Selective Electrodes (ISEs) whose lead sensing behaviours were investigated via Differential Pulse Anodic Stripping Voltammetry (DPASV) and Electrochemical Impedance Spectroscopy (EIS), subsequent to their characterization via Scanning Electron Microscopy (SEM). For all three ISEs, the electrosynthesized polymeric Ion Selective Membranes (ISM) are multi-layered with pores of diverse dimensions; a feature which allows wide linear ranges (4–107 ppm) in all cases, relative to Flame Atomic Absorption Spectroscopy (FAAS); one of the traditional “go-to” methods for metal ion quantification. Additionally, these ISEs allow selective detection of Pb2+ at concentrations below 20 ppm even in the presence of high concentrations of competing metal ions, except when excess Al3+ is present. Overall, given the relative ease of modification and low cost of these hydrazonic dibenzo-18-crown-6 ISEs, coupled with their performance, they represent a viable starting point for the development of high quality, low cost lead ISEs.

Effects of a Herbal Sex Enhancer (Vigpower) and Zinc Supplementation on Sex Hormones, Hepatic and Renal Function in Male Albino Rats

Aim: This study evaluated the effects of a herbal sex enhancer (Vigpower) and zinc supplementation on sex hormones, hepatic and renal function in male albino rats.&#x0D; Methodology: A total of 49 male Albino rats weighing between 150 to 180g were used for the study. Vigpower, Viagra and zinc were orally administered to the rats daily for 28 days. Testosterone and estradiol were quantitatively determined using a rat-specific sandwich-enzyme linked immunosorbent assay (ELISA) method. The liver enzymes alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were determined using the Reitman-Frankel method. Alkaline phosphatase (ALP) was determined using the Colorimetric endpoint method. Sodium (Na+), potassium (K+) and chloride (CL-) were determined using ion selective electrode (ISE) method. Urea was determined using Urease bertholet method. Creatinine was determined using Jaffe-Slot method and qualitative phytochemical analysis was done on Vigpower capsule using classical methods.&#x0D; Results: Phytochemical analysis revealed the presence of flavonoids, protodioscin, saponins and phenols in the herbal capsule Vigpower. Testosterone levels were significantly higher in all the treatment groups compared to the negative control, with group 7 (Vigpower + Viagra + zinc) having the highest value. Estradiol levels were significantly lower, whereas testosterone-estradiol (T/E) ratio was significantly higher in all the treatment groups compared to the negative control, except for group 4 (zinc) which showed no significant difference compared to the negative control. ALT levels in the treatment groups were not significantly different from the negative control, except for groups 6 (Viagra + zinc) and 7 (Vigpower + Viagra + Zinc), which had significantly higher levels. AST and ALP levels in the treatment groups were not significantly different from the negative control, except for group 7 (Vigpower + Viagra + Zinc), which was significantly higher than the negative control and all other treatment groups. There was no significant difference in sodium (Na+), chloride (Cl-) and urea levels in the treatment groups, compared to the negative control. Potassium (K+) and creatinine levels were significantly higher in group 7 (Vigpower + Viagra + zinc), compared to the negative control and all other treatment groups.&#x0D; Conclusion: Singular administration of Vigpower, Viagra and zinc increased testosterone levels of the male rats. Vigpower and Viagra had equipotent effects on the sex hormones and also increased the testosterone-estradiol ratio. Vigpower, Viagra and zinc administered singularly, had no impact on liver enzymes and renal function. However, the combination treatment of Vigpower, Viagra and zinc was hepatotoxic and elevated potassium and creatinine levels. Herbal sex enhancers and their combination with other medications could provoke the desired sexual effect, but may damage other organ systems and pose serious public health challenges.