Selective Electrode Research Articles

Design and optimization of a Cr(VI)-Selective Electrode based on a polymeric ß-cyclodextrin membrane modified with sulfur donor groups

This work presents the design and optimization of a new Cr(VI)-selective electrode. The new sensor is based on modifying a glassy carbon electrode with carbon quantum dots, ß-cyclodextrin, and carbon disulfide. The carbon quantum dots aided the electrical properties of the glassy carbon by improving charge transfer; the electropolymerization of ß-cyclodextrin resulted in a polymeric membrane that functions as a recognition element when modified by adding sulfur donor groups to its structure. Modifying the membrane with sulfur atoms gave the sensor excellent selectivity toward Cr(VI) ions. The electrode synthesis was optimized using a 23 factorial design; the factors studied were pH, the number of cycles in the electropolymerization, and the presence or absence of carbon nanoparticles. Eight different electrodes were constructed, and their potentiometric response to different concentrations of Cr(VI) was evaluated for all of them. The analysis of variance of the experimental design found no significant effect of any factor on the response. However, it suggests a strong interaction between the three factors studied. The sensor that presented the best analytical parameters was synthesized at pH 5 and 50 consecutive cycles in the presence of carbon quantum dots. This new electrode, with its response times of 40 s at different concentrations of the metal ion, exhibiting a slope of (66.0 ± 2.1) mV decade−1 and a detection limit of (5.2 ± 0.1)x10−7 mol L−1, can be used at pH between 0 and 3 without the effect of hydronium ions. The proposed electrode has good reproducibility and excellent selectivity against various metal ions and has significant advantages over other analysis methods. Its cost, ease of construction, easy handling, ease of operation, ease of storage and transportation, as well as good performance, short response time, and high selectivity make this electrode a valuable tool for easy, fast, and reliable monitoring of Cr(VI) in water samples, contributing to the safety and health of our environment.

Improved rate capability and energy density of high-mass hybrid supercapacitor realized through long-term cycling stability testing and selective electrode design

To render supercapacitors (SCs) more practical, they must exhibit high cycling stability of at least ten thousand cycles with commercial-level mass loadings, which differentiates them from batteries. Metal-organic framework (MOF)-based electrode materials are promising for use in energy storage systems owing to their excellent electrochemical performance. In this study, we report the electroactivities of bimetallic MOFs (Co, Ni, and Co–Ni) using a single-step, facile, and cost-effective hydro/solvothermal method. To optimize their performances, we develop a general strategy for analyzing various binder-free MOFs. Additionally, the effects of the reaction time, reaction temperature, solvents, and elements (Ni, Co, and H2BDC) on the surface morphology and electrochemical performance are investigated. Based on an analysis of the electrochemical properties of all the synthesized electrode materials, the optimal electrode delivers an ultrahigh areal capacity of 2621 µAh cm−2 (297.1 mAh g−1) at 7 mA cm−2, with a high-rate capability of 82.5 % even at 40 mA cm−2. The optimized Co–Ni MOF electrode is employed as a positive electrode to fabricate an aqueous hybrid SC (HSC) with an activated carbon-coated nickel foam electrode as a negative electrode. The as-fabricated HSC exhibits excellent electrochemical properties with exceptional cycling stability (120k cycles) and improved rate capability (60 %). Additionally, we identify factors that contribute to improved redox reactions in the Co–Ni MOF-based HSC, such as the role of Co–Ni MOFs in the redox reaction and the influences of other structural parameters on charge storage and transfer processes. Our aim is to further understand the underlying mechanisms of the improved redox reactions and thus obtain new insights into the design and optimization of Co–Ni MOF-based HSCs. Finally, the energy storage properties of the HSC are validated by using it to power different electronic devices. The promising outcomes obtained in this work can serve as a basis for the future practical implementation of high-energy-density HSCs with high mass loadings and charging rates. SynopsisTo render the practicability of hybrid supercapacitor (HSC) with enhanced energy storage properties, we investigate the electroactivities of bimetallic metal-organic frameworks (MOFs) (Co, Ni, and Co–Ni) using a single-step, facile, and cost-effective hydro/solvothermal method. To optimize their performances, a general strategy is developed for analyzing various binder-free MOFs. Additionally, the effects of the reaction time, reaction temperature, solvents, and elements (Ni, Co, and H2BDC) on the surface morphology and electrochemical performance are studied. In addition, we validate the energy storage properties of the HSC by using it to power different electronic devices. The promising outcomes obtained in this study can serve as a basis for the future practical implementation of high-energy-density HSCs with high mass loadings and charging rates.

Sex Dependence in Control of Renal Haemodynamics and Excretion in Streptozotocin Diabetic Rats-Role of Adenosine System and Nitric Oxide.

Recently, we compared an interplay of the adenosine system and nitric oxide (NO) in the regulation of renal function between male normoglycaemic (NG) and streptozotocin-induced diabetic rats (DM). Considering the between-sex functional differences, e.g., in the NO status, we present similar studies performed in female rats. We examined if the theophylline effects (non-selective adenosine antagonist) in NG and DM females with or without active NO synthases differed from the earlier findings. In anaesthetised female Sprague Dawley rats, both NG and DM, untreated or after NO synthesis blockade with L-NAME, theophylline effects, on blood pressure, renal hemodynamics and excretion, and renal tissue NO were investigated. Renal artery blood flow (Transonic probe), cortical, outer-, and inner-medullary flows (laser-Doppler technique), and renal tissue NO signal (selective electrode) were measured. In contrast to males, in female NG and DM rats, theophylline induced renal vasodilation. In NO-deficient females, theophylline induced comparable renal vasodilatation, confirming the vasoconstrictor influence of the renal adenosine. In NG and DM females with intact NO synthesis, adenosine inhibition diminished kidney tissue NO, contrasting with an increase reported in males. Lowered baseline renal excretion in DM females suggested stimulation of renal tubular reabsorption due to the prevalence of antinatriuretic over natriuretic tubular action of adenosine receptors. An opposite inter-receptor balance pattern emerged previously from male studies. The study exposed between-sex functional differences in the interrelation of adenosine and NO in rats with normoglycaemia and streptozotocin diabetes. The findings also suggest that in diabetes mellitus, the abundance of individual receptor types can distinctly differ between females and males.

Enhanced Performance of Calcium-Ion Selective Electrode Based on Chitosan/MXene/ZnO Modification

Enhanced Performance of Calcium-Ion Selective Electrode Based on Chitosan/MXene/ZnO Modification

Application of Soil Testing Sensors in Agriculture: A Review

The soil whose main role is to provide nutrients in the process of plant growth is the foundation and an important part of agriculture. Soil testing is an important step for increasing agricultural production and raising farm income. Traditional soil testing methods rely on chemical processes carried out in a laboratory. Sensors play a significant role in agriculture by direct measurement of soil chemistry through tests such as pH, moisture, nutrient content, humidity and temperature. The results of soil tests are important to get high yield with good quality produce. ISE (Ion Selective Electrode) and ISEFT (ion-sensitive field effect transistor) sensors have also been used to detect the uptake of ions by plants.

Using neural biomarkers to personalize dosing of vagus nerve stimulation

BackgroundVagus nerve stimulation (VNS) is an established therapy for treating a variety of chronic diseases, such as epilepsy, depression, obesity, and for stroke rehabilitation. However, lack of precision and side-effects have hindered its efficacy and extension to new conditions. Achieving a better understanding of the relationship between VNS parameters and neural and physiological responses is therefore necessary to enable the design of personalized dosing procedures and improve precision and efficacy of VNS therapies.MethodsWe used biomarkers from recorded evoked fiber activity and short-term physiological responses (throat muscle, cardiac and respiratory activity) to understand the response to a wide range of VNS parameters in anaesthetised pigs. Using signal processing, Gaussian processes (GP) and parametric regression models we analyse the relationship between VNS parameters and neural and physiological responses.ResultsFirstly, we illustrate how considering multiple stimulation parameters in VNS dosing can improve the efficacy and precision of VNS therapies. Secondly, we describe the relationship between different VNS parameters and the evoked fiber activity and show how spatially selective electrodes can be used to improve fiber recruitment. Thirdly, we provide a detailed exploration of the relationship between the activations of neural fiber types and different physiological effects. Finally, based on these results, we discuss how recordings of evoked fiber activity can help design VNS dosing procedures that optimize short-term physiological effects safely and efficiently.ConclusionUnderstanding of evoked fiber activity during VNS provide powerful biomarkers that could improve the precision, safety and efficacy of VNS therapies.

Improvement of the Upper Detection Limit of Ionophore-Based H+-Selective Electrodes: Explanation and Elimination of Apparently Super-Nernstian Responses.

The response range of an ion-selective electrode (ISE) has been described by counterion interference at the lower and Donnan failure at the upper detection limit. This approach fails when the potentiometric response at the upper detection limit exhibits an apparently super-Nernstian response, as has been reported repeatedly for H+-selective electrodes. While also observed when samples contain other anions, super-Nernstian responses at low pH are a problem in particular for samples that contain phthalate, a common component of commercial pH calibration solutions. This work shows that coextraction of H+ and a sample anion into the sensing membrane alone does not explain these super-Nernstian responses, even when membrane-internal diffusion potentials are taken into account. Instead, these super-Nernstian responses are explained by the formation of complexes between that anion and at least two protonated ionophore molecules. As demonstrated by experiments and explained with quantitative phase boundary models, the apparently super-Nernstian responses at low pH can be eliminated by restricting the molecular ratio of ionophore and ionic sites. Notably, this conclusion results in recommendations for the optimization of sensing membranes that, in some instances, will conflict with previously reported recommendations from the ionic site theory for the optimization of the lower detection limit. This mechanistic insight is key to maximizing the response range of these ionophore-based ISEs.

Early postpartum pumping behaviors, pumped milk volume, and achievement of secretory activation in breast pump-dependent mothers of preterm infants.

Pumping studies in mothers of preterm infants are limited by self-reported pumping behaviors and non-objective measures of pumped milk volume and secretory activation (SA). Non-randomized observational study of first 14 days postpartum in 29 mothers of preterm infants. Smart pumps measured and stored pumping behaviors and pumped milk volume. Selective ion electrodes measured sodium and sodium:potassium ratio to determine SA. Generalized estimating equations, cluster analyses and multivariate regression were used. SA was delayed (median 5.8 days) and impermanent. Each additional daily pumping increased odds of SA within 2 days by 48% (p = 0.01). High-intensity pumping mothers (N = 17) had greater daily and cumulative pumped milk volume than low-intensity pumping mothers (N = 12). Pumping variables showed daily changes in the first week, then plateaued. The first week postpartum is critical for optimizing pumping behaviors. Accurate, objective measures of pumping behaviors, pumped milk volume and SA are a research priority.

Fluoride exposure from consumption of some animal-based foods in an outermost region of Europe

Fluoride is an anion that is widely distributed in nature and can be found in varying levels in water supplies and foodstuffs. This study has been carried out considering the toxic effects in cases of chronic and high fluoride intake and the presence of this anion in foods of animal origin. The fluoride content in a total of 96 samples of animal origin (meat, poultry and poultry products; fish and seafood; milk, dairy products and eggs) was determined by potentiometry with a fluoride selective electrode (ISE). The overall mean concentration was 3.92 ± 6.04 mg/kg, with a minimum for milk (values below the detection limit of 0.01 mg/kg) and a maximum for shrimps (32.1 mg/kg). Seafood was found to have the highest fluoride concentrations and the estimated daily intake (EDI) and the percentage contribution to the adequate intake (AI) and upper-level intake (UL) were calculated. Overall, the percentage contribution to UL was less than 20 %. It was concluded that the intake of the analysed animal-based foods does not pose a toxic risk.

A smartphone-based sensor for detection of iron and potassium in food and beverage samples

A novel approach for simultaneous detection of iron and potassium via a smartphone-based potentiometric method is proposed in this study. The screen printed electrodes were modified with carbon black nanomaterial and ion selective membrane including zinc (II) phtalocyanine as the ionophore. The developed Fe3+-selective electrode and K+-selective electrode exhibited detection limits of 1.0 × 10−6 M and 1.0 × 10−5 M for Fe3+ and K+ ions, respectively. The electrodes were used to simultaneously detect Fe3+ and K+ ions in apple juice, skim milk, soybean and coconut water samples with recovery values between 90%–100.5%, and validated against inductively coupled plasma-optical emission spectrometry. Due to the advantageous characteristics of the sensors and the portability of Near Field Communication potentiometer supported with a smartphone application, the proposed method offers sensitive and selective detection of iron and potassium ions in food and beverage samples at the point of need.

Investigating the Relationship between Electrolyte Levels and ABO Blood Groups: Prospects for Customized Medicine

Human ABO blood type antigens exhibit alternative phenotypes and genetically derived glycoconjugate structures that are located on the red cell surface which play an active role in the cells' physiology and pathology. This study was carried out to evaluate the electrolytes, urea and creatinine of individuals with different ABO blood groups in Ekpoma. A total of one hundred (100) samples were used in this study. Electrolytes was estimated using ion selective electrode, urea was estimated using Berthelot method, while creatinine was estimated using Jaffe’s method. The results were presented in tables as mean ± standard deviation. Statistical analysis was done using one-way analysis of variance (ANOVA) and the student’s t-test. Significant difference was accepted at p<0.05. The results obtained showed that Sodium (Na) (mmol/L) was significantly higher (p<0.05) in subjects with blood group O (136.72±1.22) and blood group A (136.00±1.36) when compared with blood group B (134.56±2.56). Potassium (K) (mmol/L) was non-significantly higher (p>0.05) in blood group A (3.62±0.29), followed by blood group O (3.59±0.18) and least in blood group B (3.51±0.22). Bicarbonate (HCO3) (mmol/L) was non-significantly higher (p>0.05) in blood group A (21.17±1.76), followed by blood group O (20.67±1.09) and least in blood group B (20.52±0.91). Chloride (Cl) (mmol/L) was non-significantly higher in blood group O (103.20±1.81) followed by blood group A (102.10±2.35) and least in blood group B (101.60±3.58). Furthermore, Urea (mg/dl) was non-significantly higher (p>0.05) in blood group O (23.20±4.57), followed by blood group A (21.48±4.15) and least in blood group B (20.76±5.15). Similarly, Creatinine (mg/dl) was non-significantly higher in blood group O (0.65±0.15), followed by blood group A (0.63±0.12) and least in blood group B (0.62±0.15). In conclusion, electrolytes, urea and creatinine were higher in blood group A and O compared with blood group B. With respect to gender, Na, HCO3, Cl, Urea and Creatinine were significantly higher in male subjects compared with female subjects. There was no significant difference in electrolytes, urea and creatinine of the subjects with respect to age (p>0.05). Further studies should be carried out to understand the mechanism behind increase in electrolytes, urea and creatinine in certain blood group compared with others.

Transition metal complexation assisted stabilization of the deprotonated organic moiety: A strategy for colorimetric and electrochemical recognition of fluoride ion in water medium with organic probe molecules

Excess consumption of fluoride through drinking water causes detrimental effects to human health which has been a serious global concern. This situation demands routine monitoring of fluoride in drinking water in fluoride affected regions around the world. A plethora of organic molecules has been demonstrated as chemosensors based on the fluoride induced deprotonation reaction of the probe molecules. However, most of the probe molecules fail to react with fluoride in aqueous medium which limits their application. Herein, we have demonstrated a metal ion, Ni(II) mediated strategy to retain the reactivity and the sensitivity of the probe molecule towards fluoride ion in aqueous medium with the help of two benzothiazole based probe molecules (R and P). Both the probe molecules showed retention of the affinity towards fluoride ion in aqueous medium in presence of Cu2+ ion but the colorimetric response is not upto the mark. On the other hand, the probe molecule P showed excellent affinity and colorimetric response towards aqueous fluoride ion in presence of Ni2+ ion. The methodology is validated with UV–Vis spectroscopy and Differential pulse voltammetry (DPV) technique. Probe molecule P in presence of Ni2+ ion showed limit of detection values 0.60 ppm and 0.57 ppm w.r.t. UV–Visible spectroscopy and DPV technique respectively. Furthermore, the efficiency of the methodology w.r.t. P was tested with real samples collected from the fluoride affected areas of Assam, India and found that the data corroborates well with the results of ion selective electrode. This methodology can provide a new dimension in the development of a low cost method for routine sensing of fluoride ion with organic probe molecules in drinking water for low resource world.

The effects of microplastics on ionoregulatory processes in the gills of freshwater fish and invertebrates: A prospective review

From review of the very few topical studies to date, we conclude that while effects are variable, microplastics can induce direct ionoregulatory disturbances in freshwater fish and invertebrates. However, the intensity depends on microplastic type, size, concentration, and exposure regime. More numerous are studies where indirect inferences about possible ionoregulatory effects can be drawn; these indicate increased mucus production, altered breathing, histopathological effects on gill structure, oxidative stress, and alterations in molecular pathways. All of these could have negative effects on ionoregulatory homeostasis. However, previous research has suffered from a lack of standardized reporting of microplastic characteristics and exposure conditions. Often overlooked is the fact that microplastics are dynamic contaminants, changing over time through degradation and fragmentation and subsequently exhibiting altered surface chemistry, notably an increased presence and diversity of functional groups. The same functional groups characterized on microplastics are also present in dissolved organic matter, often termed dissolved organic carbon (DOC), a class of substances for which we have a far greater understanding of their ionoregulatory actions. We highlight instances in which the effects of microplastic exposure resemble those of DOC exposure. We propose that in future microplastic investigations, in vivo techniques that have proven useful in understanding the ionoregulatory effects of DOC should be used including measurements of transepithelial potential, net and unidirectional radio-isotopic ion flux rates, and concentration kinetic analyses of uptake transport. More sophisticated in vitro approaches using cultured gill epithelia, Ussing chamber experiments on gill surrogate membranes, and scanning ion selective electrode techniques (SIET) may also prove useful. Finally, in future studies we advocate for minimum reporting requirements of microplastic properties and experimental conditions to help advance this important emerging field.

Sequestration of cyanide ions from aqueous medium by physio-chemically fabricated biochar of peels of banana and grape fruit in ecofriendly way

Pakistan is an agricultural country producing plenty of fruits, like: mango, banana, apple, peaches, grapes, plums, variety of citrus fruits including lemon, grapefruit, and oranges. So far the peels of most of the fruits are usually wasted and not properly utilized anywhere. In this work, the peels of banana and grapefruit are converted into biochar by slow pyrolysis under controlled supply of air and used for sequestering cyanide ions from aqueous medium after chemical modification with ZnCl2 and sodium dodecyl sulfate (SDS). The modified biochar was characterized by various instrumental techniques, like: SEM, FTIR, TGA, and CHNS. Different parameters, like: time, temperature, pH, and dose of adsorbent affecting the adsorption of cyanide ions, onto prepared biochar were optimized and to understand the adsorption phenomenon, kinetic and thermodynamic studies were performed. Concentration of cyanide ions was estimated by employing standard ion selective electrode system and it is found that Sodium Dodecyl Sulfate treated biochar of banana peels shown more adsorption capacity, i.e.,: 17.080 mg/g as compared to all samples. Present work revealed that the biochar produced from the fruit waste has sufficient potential to eliminate trace quantities of cyanide from water, especially after treatment with sodium dodecyl sulfate.

The chemical and optical stability evaluation of injectable restorative materials under wet challenge

ObjectivesTo investigate and compare the chemical and optical stability of four restorative composite materials: two injectable resins, one flowable resin and one compomer. MethodsTwo injectable nano-filled composite resins: G-aenial Universal (GU) and Beautifil Injectable XSL (BI), a flowable composite resin: Filtek Supreme Flowable (FS) and a compomer: Dyract Flow (DF), in A2 shade were tested and compared. Water sorption and solubility were conducted according to ISO4049:2019 standard; ICP-OES and F-ion selective electrode were used to test the elemental release; Degree of conversion (DC) was obtained by using FTIR; water contact angle was obtained by static sessile drop method, and a spectrophotometer was used for optical properties (ΔE⁎, ΔL⁎ and TP). SPSS 28.0 was used for statistical analysis and the significant level was pre-set as α = 0.05. ResultsGU performed the best in water sorption and solubility, FS had the lowest elemental release, the best colour stability, and the highest DCIM and DC24-h. DF, the compomer had the lowest, and GU and BI, the injectable composites had the largest water contact angle, respectively. Correlations were found between water sorption and water solubility. ConclusionsThe four composite restorative materials showed different chemical and optical behaviours. Overall, composite resins performed better than compomer, while additional laboratory and in vivo tests are necessary to obtain a more comprehensive comparison between injectable and flowable composite resins. Wsp and Wsl are influenced by many common factors, and the values are highly positively related. Clinical SignificanceA comprehensive understanding of materials is crucial before selecting materials for clinical practice. Composite resins rather than compomers are recommended because of their exceptional properties, which make them eligible for a wide range of clinical applications and an elongated lifespan.

Touch–based potentiometric sensors for simultaneous detection of urea and ammonium from fingertip sweat

Urea is a biomarker for diagnosis and management of multiple disorders. The measurement of urea could help in the diagnosis of patients with kidney dysfunction. Despite their attractive analytical performances, the existing urea measurement methods are still limited to sophisticated and time–consuming or require invasive blood sampling. Herein, a reliable noninvasive, simple, and disposable touch–based potentiometric sensor is fabricated for rapid monitoring of fingertip sweat urea. Novel touch–based urea detection relies on immobilized urease recognition and a solid–contact ammonium–ion–selective electrode, along with a screen–printed carbon working electrode modified carboxylated carbon nanotubes for enhancing sensor’s sensitivity. The fingertip sweat under sedentary rest conditions can be instantaneously collected on customized porous polyvinyl alcohol hydrogel transporting sweat to working electrode surface where the hydrolysis of urea is catalyzed, generating bicarbonate and ammonium. The resulting ammonium can be detected with ion–selective transducer, enabling indirect monitoring of sweat urea. Potential interference from co–existing ammonium in human sweat is addressed by developing a dual disposable potentiometric sensor, consisting of urea and ammonium sensors on a single strip platform allowing for simultaneous touch–based detection of sweat urea and ammonium. The resulting dual disposable sensing system offers rapid urea and ammonium monitoring within a group of healthy human subjects, along with a good correlation with R2 = 0.974 between the sweat urea and capillary blood urea levels. Additional confirmation among a broad sample of individuals along with the validation of sensor data through centralized laboratory tests will establish the practicality of simultaneously monitoring urea and ammonium levels.

Green Electrochemical Sensing: Novel Ion-Selective Electrode Method for Precise Determination of Dimenhydrinate and its Metabolite along with Cinnarizine in Pharmaceutical and Plasma Samples

Green and sustainable scientific research is crucial for health and environmental improvement. Electrochemical analysis simplifies complex processes, saving time and cost. Ion selective electrode method, a key in green analytical chemistry, was utilized. A highly selective solid contact sensor was developed for two applications, detecting cinnarizine (CIN) and dimenhydrinate (DMH) in pharmaceuticals, and identifying CIN and diphenhydramine (DIP) in human plasma. Careful selection of ionophores ensured accurate detection. Multi-wall carbon-nanotubes (MWCNTs) facilitate rapid and precise measurement. The concentration range for CIN, DMH, and DIP was 1 × 10−6 M to 1 × 10−2 M, with mean recovery% of 100.07 ± 0.80, 100.12 ± 0.76, and 100.07 ± 0.53, respectively. Validation parameters exhibited accuracy and precision, with accuracy results of 100.87 ± 0.89, 99.96 ± 0.42, and 99.82 ± 0.31, and LODs of 0.5 × 10−6, 1.0 × 10−7, and 0.2 × 10−6 for CIN, DMH, and DIP, respectively. The study highlighted benefits like speed, economy, and sustainability, emphasizing the electrode’s reusability. SWOT analysis and environmental assessments further underscored its advantages, promising applications in pharmaceutical analysis and quality control.

The Relationship Between Potassium And Ureum Levels Of New Drugs In Drug Resistant Tuberculosis Patients

The use of new types of drugs in RO TB patients will cause disturbances in the body's electrolytes, especially potassium levels, as well as disturbances in urea levels caused by the excretion of urea that is retained in the body. Continuous increases in urea in the body result in the kidneys not being able to work optimally. The aim of this study was to determine the relationship between potassium levels and urea levels on new types of drugs in RO TB patients. The research method used is analytical observational with a cross sectional approach. This research was conducted on 16 February – 16 March 2023 with research subjects being RO TB patients who received treatment with a new type of drug at the Lung Hospital dr. Ario Wirawan Salatiga as many as 21 respondents using a sampling technique that is the total population. Potassium levels were measured using the ISE (Ion Selective Electrode) method and urea levels used the enzymatic UV test method. The data was then processed using the Shapiro-Wilk normality test, then continued with prerequisite tests (crosstab test and homogeneity test) then continued with hypothesis testing, because my data scale was ratio and nominal, the alternative test used was the Chi-Square Test. The equipment test results obtained a homogeneity test with a P value of 0.698 and 0.610 (0.05), meaning the data was homogeneous. The test results for the relationship between potassium and urea levels on new types of drugs for RO TB patients were Chi-Square hypothesis test results with a P value of 0.152 and 0.384 ( 0.05) means there is no relationship between potassium levels and urea levels on new types of drugs in RO TB patients. The results show that the TB drugs bedaquiline and delamanid do not cause kidney function disorders so that RO TB patients can consume these TB drugs regularly.

Hydrothermal Destruction and Defluorination of Trifluoroacetic Acid (TFA).

Per- and polyfluoroalkyl substances (PFAS) have received increased attention due to their environmental prevalence and threat to public health. Trifluoroacetic acid (TFA) is an ultrashort-chain PFAS and the simplest perfluorocarboxylic acid (PFCA). While the US EPA does not currently regulate TFA, its chemical similarity to other PFCAs and its simple molecular structure make it a suitable model compound for studying the transformation of PFAS. We show that hydrothermal processing in compressed liquid water transforms TFA at relatively mild conditions (T = 150-250 °C, P < 30 MPa), initially yielding gaseous products, such as CHF3 and CO2, that naturally aspirate from the solution. Alkali amendment (e.g., NaOH) promotes the mineralization of CHF3, yielding dissolved fluoride, formate, and carbonate species as final products. Fluorine and carbon balances are closed using Raman spectroscopy and fluoride ion selective electrode measurements for experiments performed at alkaline conditions, where gas yields are negligible. Qualitative FTIR gas analysis allows for establishing the transformation pathways; however, the F-balance could not be quantitatively closed for experiments without NaOH amendment. The kinetics of TFA transformation under hydrothermal conditions are measured, showing little to no dependency on NaOH concentration, indicating that the thermal decarboxylation is a rate-limiting step. A proposed TFA transformation mechanism motivates additional work to generalize the hydrothermal reaction pathways to other PFCAs.

Ammonia transport in the excretory system of mosquito larvae (Aedes aegypti): Rh protein expression and the transcriptome of the rectum

The role of the mosquito excretory organs (Malpighian tubules, MT and hindgut, HG) in ammonia transport as well as expression and function of the Rhesus (Rh protein) ammonia transporters within these organs was examined in Aedes aegypti larvae and adult females. Immunohistological examination revealed that the Rh proteins are co-localized with V-type H+-ATPase (VA) to the apical membranes of MT and HG epithelia of both larvae and adult females. Of the two Rh transporter genes present in A. aegypti, AeRh50-1 and AeRh50-2, we show using quantitative real-time PCR (qPCR) and an RNA in-situ hybridization (ISH) assay that AeRh50-1 is the predominant Rh protein expressed in the excretory organs of larvae and adult females. Further assessment of AeRh50-1 function in larvae and adults using RNAi (i.e. dsRNA-mediated knockdown) revealed significantly decreased [NH4+] (mmoll-1) levels in the secreted fluid of larval MT which does not affect overall NH4+ transport rates, as well as significantly decreased NH4+ flux rates across the HG (haemolymph to lumen) of adult females. We also used RNA sequencing to identify the expression of ion transporters and enzymes within the rectum of larvae, of which limited information currently exists for this important osmoregulatory organ. Of the ammonia transporters in A. aegypti, AeRh50-1 transcript is most abundant in the rectum thus validating our immunohistochemical and RNA ISH findings. In addition to enriched VA transcript (subunits A and d1) in the rectum, we also identified high Na+-K+-ATPase transcript (α subunit) expression which becomes significantly elevated in response to HEA, and we also found enriched carbonic anhydrase 9, inwardly rectifying K+ channel Kir2a, and Na+-coupled cation-chloride (Cl-) co-transporter CCC2 transcripts. Finally, the modulation in excretory organ function and/or Rh protein expression was examined in relation to high ammonia challenge, specifically high environmental ammonia (HEA) rearing of larvae. NH4+ flux measurements using the scanning-ion selective electrode (SIET) technique revealed no significant differences in NH4+ transport across organs comprising the alimentary canal of larvae reared in HEA vs freshwater. Further, significantly increased VA activity, but not NKA, was observed in the MT of HEA-reared larvae. Relatively high Rh protein immunostaining persists within the hindgut epithelium, as well as the ovary, of females at 24-48h post blood meal corresponding with previously demonstrated peak levels of ammonia formation. These data provide new insight into the role of the excretory organs in ammonia transport physiology and the contribution of Rh proteins in mediating ammonia movement across the epithelia of the MT and HG, and the first comprehensive examination of ion transporter and channel expression in the mosquito rectum.