Ethylenediaminetetraacetic Acid Research Articles

Microbial challenges and solutions in root canal therapy

Root canal therapy (RCT) faces significant challenges due to microbial invasion and biofilm formation within the root canal system. The intricate anatomy of root canals, including isthmuses, lateral canals, and apical deltas, provides a conducive environment for pathogenic microorganisms, complicating effective disinfection. Key pathogens such as Enterococcus faecalis and Candida albicans are highly resilient, capable of forming biofilms that protect them from antimicrobial agents and host defences. Current antimicrobial strategies in endodontics combine mechanical instrumentation with chemical disinfection. Mechanical debridement, though essential, often falls short of thoroughly cleaning the complex root canal anatomy. Sodium hypochlorite (NaOCl), the gold standard irrigant, exhibits broad-spectrum antimicrobial properties but struggles to penetrate biofilms and dentinal tubules fully. Adjunctive solutions like chlorhexidine (CHX) and ethylenediaminetetraacetic acid (EDTA) enhance the antimicrobial efficacy of NaOCl by providing prolonged action and removing the smear layer, respectively. Intracanal medicaments, such as calcium hydroxide (Ca(OH)2), are utilized to maintain antimicrobial activity between treatment sessions. Despite its high pH and effectiveness against a wide range of bacteria, Ca(OH)2 shows limited efficacy against biofilm-forming bacteria like Enterococcus faecalis. Innovations in irrigation techniques, such as passive ultrasonic irrigation (PUI) and laser-activated irrigation (LAI), have improved the delivery and activation of irrigants, enhancing their ability to disrupt biofilms and penetrate the root canal system. Nanoparticle-based irrigants and medicaments represent a promising advancement in endodontic disinfection. Their small size and large surface area allow for better penetration and interaction with bacterial cells, significantly reducing bacterial load in the root canal system. Combining traditional and advanced antimicrobial strategies is essential for overcoming the limitations of current methods and improving the success rates of endodontic therapy. Understanding the mechanisms of microbial invasion and biofilm formation, along with integrating emerging technologies, can lead to more effective disinfection protocols. This approach aims to enhance treatment outcomes and ultimately ensure the longevity of endodontically treated teeth.

The effect of two different contemporary chelating agents on vital pulp therapy in mature permanent teeth with irreversible pulpitis using bioceramic material: randomized clinical trial.

Vital pulp therapy maintained functionality, vitality, and asymptomatic teeth. Compared to normal root canal treatment, pulpotomy was more helpful for irreversible pulpitis in adult permanent teeth. The research was aimed to assess effectiveness of vital pulp therapy using mineral trioxide aggregate with Apple Vinegar and Ethylene diamine tetra acetic acid (17%) for five minutes in adult carious exposed pulp of permanent teeth. Forty patients between 18 and 50 years old with a clinical diagnosis of symptomatic irreversible pulpitis but no periapical radiolucency were then divided randomly into two groups based on the irrigation method; ethylene diamine tetraacetic acid or apple vinegar. If pulpal bleeding could not be managed in less than six minutes, the assigned procedure was abandoned. After mineral trioxide aggregate application as a pulpotomy agent, glass ionomer and composite restoration were placed. Using a visual analogue scale, the pre and post-operative pain were recorded after 2,6,24,48, and 72h. Success was assessed using radiographic and clinical examination data at three, six, and twelve months. The success rate was discovered to be non-statistically significant in both groups after a year follow-up. Apple vinegar had a lower mean value than ethylene diamine tetra acetic acid at the preoperative baseline pain level, which was significant.Postoperatively, the ethylene diamine tetraacetic acid group reported the greatest mean value after two hours while Apple vinegar group reported the lowest mean values after 48h (P < 0.05). After 72h, pain level recorded insignificant difference. Apple vinegar yielded a marginally successful outcome but substantially improved pain alleviation. The trial was registered in Clinical trials.gov with this identifier NCT05970536 on 23/7/2023.

The phytosiderophore analogue proline-2′-deoxymugineic acid is more efficient than conventional chelators for improving iron nutrition in maize

ABSTRACT Iron (Fe) is an essential nutrient but has poor bioavailability because of its low solubility under conditions of high pH, such as calcareous soils. Previously, we synthesized an analogue of the natural Fe(III) chelator 2′-deoxymugineic acid secreted by graminaceous plants for efficient Fe uptake, designated as proline-2′-deoxymugineic acid (PDMA). Soil application of Fe(III)-PDMA ameliorated symptoms of Fe deficiency in rice. In the present study, we explored the potential of PDMA as Fe nutrition supplement in maize, a major graminaceous crop, and rice for comparison. In calcareous soil pots, Fe deficiency chlorosis of maize was efficiently recovered by a single application of Fe(III)-PDMA. In contrast, maize plants treated with conventional Fe(III)-chelator complexes, such as Fe(III)-ethylenediaminetetraacetic acid (EDTA) or Fe(III)-N,N′-di(2-hydroxybenzyl)ethylenediamine-N,N′-diacetic acid monohydrochloride (HBED), showed little or no recovery. Similarly, rice Fe chlorosis in calcareous soil pots was efficiently recovered by a single application of Fe(III)-PDMA, but not by other conventional Fe(III)-chelator complexes. Application of Fe(III)-PDMA was also effective in ameliorating Fe deficiency chlorosis in hydroponically grown maize seedlings; other Fe(III)-chelator complexes showed minimal or no efficacy. Addition of low concentrations of metal-free PDMA recovered Fe chlorosis of maize or rice in the presence of Fe(III)-EDTA, suggesting possible ligand exchange from EDTA to PDMA for subsequent Fe(III)-PDMA uptake by ZmYS1 and OsYSL15 transporters. Similar effects were observed with Fe(III)-HBED, which has a higher stability constant, but to a lesser extent than Fe(III)-EDTA, suggesting that ligand exchange from HBED to PDMA might be less prone to occur than for chelators with moderate stability constants, such as EDTA. Ferric-chelate reductase assays of maize roots showed substantial reduction of Fe(III)-PDMA, but this reduction activity was not increased under Fe-deficient condition. These results suggested that PDMA is an efficient reagent for improvement of Fe nutrition in graminaceous crops, including maize, because of suitability of Fe(III)-PDMA as a substrate for chelation-based Fe uptake systems.

HIV Diagnostic Algorithms in A Resource-Limited Setting: A Comparative Study

Background: Adoption of appropriate HIV testing algorithm is essential for quality HIV diagnostic results. Whether rapid enzyme immunoassay (rEIA) or combination of rapid enzyme immunoassay and enzyme-linked immunosorbent assay (rEIA-ELISA) alternative confirmatory algorithm is enough to make accurate HIV diagnosis has been a subject of controversies. Recent evaluation of national algorithm for HIV testing presented some discrepancies in results. Again, current guideline prescribed discontinuity of Western blot supplemental test and its replacement with Geenius HIV-1/ HIV-2 differentiation test followed by nucleic acid testing. The objective of this study is to compare HIV-1 testing algorithms using ELISA-NAT algorithm as the gold standard for HIV-1 diagnosis, and rEIA-Western blot and ELISA-Western blot as alternative confirmatory algorithms for HIV-2 diagnosis. Methods: This is a comparative study involving a cohort of 173 (98.9%) HIV-positive subjects and two (1.1%) HIV-negative subjects initially diagnosed on the basis of rEIA algorithm. Plasma samples separated from ethylene diamine tetra-acetic acid anticoagulated blood were used for further analyses. Fourth generation HIV antigen-antibody kit was used for further testing to make up rEIA-ELISA algorithm. Analyses with Western blot 1 and 2 assays were done as supplemental tests to make up alternative rEIA-Western blot and ELISA-Western blot confirmatory algorithms. Research subjects were further tested for HIV-RNA under PEPFAR plan. The sensitivity, specificity, positive predictive value and negative predictive value of algorithms were compared using the descriptive statistics of the SPSS version 17. Results: The HIV testing analyses showed 100% sensitivity, specificity, positive predictive value and negative predictive value from algorithm to algorithm especially for HIV-1 diagnosis. Use of combined ELISA-NAT confirmatory algorithm validated outcomes of rEIA-Western blot and ELISA-Western blot alternative confirmatory algorithms for HIV-1 diagnosis. Among HIV-1 positive samples tested, 50.0-60.7% HIV-2 Western blot indeterminate result was obtained and 7.1-10.7% HIV-1/HIV-2 co-infections were observed. Conclusion: The rEIA or national algorithm and its combination with enzyme-linked immunosorbent assay are reliable alternative confirmatory algorithms for the diagnosis of established HIV-1infection in resource-limited settings but not for HIV-2. Diagnosing acute HIV infection with current algorithm is limited and still require further review.

In-situ electrochemical mapping of local activity on Zn and Zn-Al alloy electrodes by scanning electrochemical microscopy

Alternating-current scanning electrochemical microscopy (AC-SECM) is introduced to monitor the local activity of Zn and Zn-10Al alloy electrodes. In-situ AC-SECM maps at potentials near the open circuit potential (OCP) in 2 M NaCl (pH 10) indicate that the surfaces of Zn and Zn-10Al alloy electrodes are covered with the passivation layer. When the electrolyte is exchanged with a 0.1 M ethylenediaminetetraacetic acid (EDTA) containing electrolyte, AC-SECM maps at the potential near the OCP clearly reveal the active Zn and the distinct difference between Al- and Zn-rich phases. Thereby, it is demonstrated that EDTA enhances the electrochemical activities of Zn and Zn-10Al alloy electrodes. With shifting the potential to anodic potential of −1.0 V in 0.1 M EDTA containing electrolyte, the interfacial difference between Al- and Zn-rich phases slowly disappears in AC-SECM maps, confirming that the local activity of the surface observed by AC-SECM is only attributed to the metal-EDTA complex. It is noteworthy that the hindered diffusion at the confined space between the tip and the substrate (∼ 10 µm) certainly influences on the local activities of Zn and Zn-10Al alloy electrodes. Additionally, AFM results indicate that the slightly different interactions of EDTA with Al- and Zn-rich phases cause the roughness contrast.

Stability of adrenocorticotropic hormone in whole blood samples: effects of storage conditions.

Adrenocorticotropic hormone (ACTH) is a peptide secreted by pituitary gland that plays an important role in regulating cortisol secretion. Its determination is difficult because of instability in whole blood. Several factors that influence ACTH stability in blood before analysis have been identified: temperature, hemolysis, time to centrifugation and presence of protease inhibitors. Published results on ACTH whole blood stability seem contradictory. We performed a stability study in 10 healthy volunteers. Three different conditions were tested: ethylenediaminetetraacetic acid (EDTA) at 4 °C, EDTA + aprotinin at 4 °C, EDTA + aprotinin at room temperature. Stability was evaluated for 8 hours. Adrenocorticotropic hormone measurements and hemolysis index were performed respectively on Cobas e602 and c701 (Roche Diagnostics, Mannheim, Germany). We compared percentage deviations with total change limit using a threshold of 7.5%. We showed that ACTH is stable 8 hours with EDTA at 4 °C, 4 hours with EDTA + aprotinin at 4 °C and 2 hours with EDTA + aprotinin at 22 °C. Aprotinin does not appear to give ACTH greater stability but can be used without exceeding 4 hours at 4 °C. Refrigerated pouch transport also seems to be more appropriate for ACTH in whole blood.

Assessment of the Effectiveness of Desensitizing Dentifrices on Management of Dental Hypersensitivity: An In Vitro Study.

The current study aimed to assess the efficiency of two desensitizing dentifrices on the management of dental hypersensitivity. For the purpose of this investigation, 60 extracted human sound premolar teeth that were removed for orthodontic purposes were collected. On the buccal cervical areas, an inverted-cone bur was used to create cavities that were 2 mm deep and 3 mm wide. The blocks were submerged in 17% ethylenediaminetetraacetic acid (EDTA) for 40 minutes in order to ensure the complete dentin tubule opening. Following preparation, all samples were split into three groups, each containing 20 samples, Group A: Control, Group B: Dentifrice containing calcium sodium phosphosilicate, Group C: Dentifrice containing casein phosphopeptide-amorphous calcium phosphate (CPP-ACP). Scanning electron microscopy (SEM) was used to assess the occlusion of dentinal tubules. One-way analysis of variance (ANOVA) was used to assess the desensitization efficacy of dentifrices. At a p-value less than 0.05, statistical significance was determined. Before application of different dentifrices, the maximum dentinal tubules opened in dentifrice containing CPP-ACP group (4.24 ± 0.10) followed by control group (4.18 ± 0.01) and dentifrice containing calcium sodium phosphosilicate (4.12 ± 0.06). And there was no significant difference between the different dentifrice groups (p > 0.001). After application of different dentifrices, the highest occlusion of dentinal tubules found in dentifrice containing CPP-ACP group (2.50 ± 0.05) followed by dentifrice containing calcium sodium phosphosilicate (2.84 ± 0.10) and control group (4.02 ± 0.07) and there was a highly significant difference between the different dentifrice groups (p < 0.001). On conclusion, dentifrice containing CPP-ACP exhibited the highest level of dentinal tubule occlusion in comparison to the control group and dentifrice containing calcium sodium phosphosilicate. Dentinal hypersensitivity (DH) is a condition that is frequently experienced. With variable outcomes, a number of products are utilized in the management of DH. Need is felt in dentistry for a material that chemically reacts, physically occludes and adheres intimately to dentinal tubules to reduce the possibility of its recurrence. How to cite this article: Pulipaka S, Ramanna PK, Samson A, et al. Assessment of the Effectiveness of Desensitizing Dentifrices on Management of Dental Hypersensitivity: An In Vitro Study. J Contemp Dent Pract 2024;25(5):494-497.

Enhanced Removal of Cd(II) Ions from Aqueous Media via Adsorption on Facilely Synthesized Copper Ferrite Nanoparticles.

In this study, magnetic copper ferrite (CuFe2O4) nanoparticles were synthesized via the Pechini sol-gel method and evaluated for the removal of Cd(II) ions from aqueous solutions. PF600 and PF800 refer to the samples that were synthesized at 600 °C and 800 °C, respectively. Comprehensive characterization using FTIR, XRD, FE-SEM, HR-TEM, and EDX confirmed the successful formation of CuFe2O4 spinel structures, with crystallite sizes of 22.64 nm (PF600) and 30.13 nm (PF800). FE-SEM analysis revealed particle diameters of 154.98 nm (PF600) and 230.05 nm (PF800), exhibiting spherical and irregular shapes. HR-TEM analysis further confirmed the presence of aggregated nanoparticles with average diameters of 52.26 nm (PF600) and 98.32 nm (PF800). The PF600 and PF800 nanoparticles exhibited exceptional adsorption capacities of 377.36 mg/g and 322.58 mg/g, respectively, significantly outperforming many materials reported in the literature. Adsorption followed the Langmuir isotherm model and pseudo-second-order kinetics, indicating monolayer adsorption and strong physisorption. The process was spontaneous, exothermic, and predominantly physical. Reusability tests demonstrated high adsorption efficiency across multiple cycles when desorbed with a 0.5 M ethylenediaminetetraacetic acid (EDTA) solution, emphasizing the practical applicability of these nanoparticles. The inherent magnetic properties of CuFe2O4 facilitated easy separation from the aqueous medium using a magnet, enabling efficient and cost-effective recovery of the adsorbent. These findings highlight the potential of CuFe2O4 nanoparticles, particularly PF600, for the effective and sustainable removal of Cd(II) ions from water.

Development and validation of stability indicating HPLC-DAD assay of adapalene, methylparaben and propylparaben in a cosmeceutical gel matrix with blueness, greenness and whiteness assessment via relative ranking: An ab initio-sub finem juxtaposed non-traditional approaches

Adapalene (ADA) is primarily used as a cosmeceutical gel in the treatment of mild-moderate acne and is also used off-label to treat keratosis pilaris as well as other skin conditions. A stability-indicating fit-for-purpose (FFP) method has been developed for co-determination of ADA, methylparaben (MPN), and propylparaben (PPN) combined in a cosmeceutical gel dosage form. This method was based on a reversed-phase RP-HPLC separation of the cited analytes. It avoided the use of tetrahydrofuran (THF), which is commonly used by both compendial and published procedures for determination of ADA, thus improving method blueness (applicability), greenness and whiteness. The method development and validation followed non-traditional eco-friendly approaches including chemical simulations and empirical modelling. The HPLC separation was performed on an RP Zorbax Eclipse XDB-C8 analytical column [150 × 4.6 mm, 5 µm (80 Å)] with gradient elution system of HPLC grade acetonitrile and 50 mM aqueous sodium dihydrogen phosphate buffer containing 5 mM ethylenediaminetetraacetic acid (EDTA) adjusted to pH 8.0 as the mobile phase at a flow rate of 2.5 mL min−1 and column oven was set at 25 °C. EDTA played an important role for reproducibility of retention time of the three analytes especially for ADA. It controlled deprotonation of the three acidic analytes under study and hence reproduce their ionization, hydrophobicity, and hence retention time. Quantitation was achieved with the photodiode array detection (DAD) at wavelengths of 256 nm for both MPN and PPN and 312 nm for ADA. Target Measurement Uncertainty (TMU) for the three analytes was determined via two approaches; misclassification rates approach employing 100,000 Monte Carlo simulations (MCS) and in-specification probability (ISP) to ascertain fitness-for-purpose of the proposed method. Microsoft Excel workbooks were developed for both TMU calculation approaches in addition to calculation of procedure capability index (Ppk) and sigma level for each analyte and attached in the Supplementary material. Moreover, linearity of the method underwent additional assessment using the previously mentioned TMU and procedure capability determination techniques. The robustness of the method was checked using Plackett-Burman experimental design (PBD) as an empirical modelling technique which was examined thoroughly to detect some interactions. The calibration graphs for each drug were rectilinear in the range of 0.34–7.08, 0.38–7.00 and 0.08–1.75 µg mL−1 for ADA, MPN, and PPN, respectively. The stress testing revealed photostability of the three components and variable degrees of degradation in the other conditions. The proposed HPLC-DAD method was successfully validated and applied for the determination of the investigated analytes in a gel matrix. In addition, method blueness and greenness were comparatively evaluated via very recent approaches of Blue Applicability Grade Index (BAGI), Green Solvents Selection Tool (GSST), Spider Diagram for Assessment of the Green Analytical Index (SDAGI), Analytical Method Greenness Score (AMGS), Carbon Footprint (CF), Modified Complementary Green Analytical Procedure Index (ComplexMoGAPI), and Analytical GREEnness Metric Approach (AGREE). Furthermore, the method whiteness was assessed via Red Green Blue Twelve (RGB 12) model following a relative ranking approach.

Modification of carbapenemase inhibition test and comparison of its performance with NG-Test CARBA 5 for detection of carbapenemase-producing enterobacterales.

Adequately and accurately identifying carbapenemase-producing Enterobacterales (CPE) is vital for selecting appropriate antimicrobial therapy and implementing effective infection control measures. This study aims to optimize the phenotypic detection method of carbapenemase for routine diagnostics in clinical microbiology laboratories. Carbapenemase genes in 2665 non-duplicate carbapenem-resistant Enterobacterales (CRE) clinical strains collected from various regions of China were confirmed through whole-genome sequencing (WGS). The carbapenemase inhibition test (CIT) was conducted and interpreted using different methods and breakpoints, then compared with the NG-Test CARBA 5 for carbapenemase detection. The diagnostic performance of the CIT method was optimal when the carbapenemase types were determined by comparing the inhibition zone diameters of the imipenem disc with 3-aminophenylboronic acid (APB) plus ethylenediaminetetraacetic acid (EDTA) to those of the imipenem disc with either APB or EDTA alone, with a breakpoint of 4mm. The overall sensitivities of the current CIT, the modified CIT and NG-Test CARBA 5 were 91.4%, 94.9% and 99.9%, respectively. For detecting isolates co-producing Klebsiella pneumoniae carbapenemase (KPC) and metallo-β-lactamases (MBLs), the modified CIT method had higher sensitivity than the current method (70.0%vs. 53.3%), though this difference was not statistically significant (p=0.063). The NG-Test CARBA 5 showed excellent performance for multi-carbapenemases diagnosis, with sensitivity and specificity of 97.1% and 100%, respectively. Optimizing and standardizing the CIT method for clinical use is necessary. It has certain advantages in diagnosing multi-carbapenemase and rare carbapenemase production. However, for identifying common carbapenemase types, the NG-Test CARBA 5 demonstrated superior performance.

Reversal of heavy arterial calcification in a rat model of chronic kidney disease using targeted ethylene diamine tetraacetic acid-loaded albumin nanoparticles.

Elastin degradation and severe calcification in the medial layer of the vessel wall, known as medial arterial calcification (MAC), is typical in the aging population and patients with metabolic disorders, such as diabetes and chronic kidney disease (CKD). We have previously reported that ethylene diamine tetraacetic acid (EDTA) delivery to the site of calcification can be achieved by tagging nanoparticles with an elastin antibody that recognizes explicitly damaged elastin, and such systemic therapy can remove focal calcium deposits from the calcified arteries in CKD rodent model. The current study aims to test whether heavy calcification seen throughout arterial tree and kidneys in CKD can be reversed with nanoparticle therapy. Thirty healthy male Sprague-Dawley rats weighing approximately 300 g, were placed on an adenine diet for 21 non-consecutive days to induce kidney failure, followed by daily vitamin D3 (VitD3) injections for 4 sequential days to cause severe calcification throughout the cardiovascular system and kidneys. DiR-dye loaded and elastin antibody conjugated albumin nanoparticles were used to confirm the targeting of nanoparticles to the calcification area. The rats were divided into two groups for targeted removal of calcification starting at day 7 of the last doses of VitD3. The experimental group received biweekly IV injections of anti-elastin antibody conjugated EDTA loaded human serum albumin nanoparticles (EDTA-HSA-El-Ab NPs), while the sham controls received blank nanoparticles (Blank-HSA-El-Ab NPs) (5 injections in total). Micro-computed tomography (microCT) was used to analyze the extent of calcification. Reverse transcription polymerase chain reaction (RT-PCR) and immunohistochemistry studies were performed for osteogenic markers, including bone morphogenic protein 2 (BMP2), runt-related transcription factor 2 (RUNX2), and tissue non-specific alkaline phosphatase (TNAP). For comparison, aortic ring organ cultures from healthy rats were treated with high phosphate to induce calcification in vitro, and then they were treated with EDTA. Human calcified femoral arteries were also treated ex vivo with EDTA-HSA-EL-Ab NPs to test if nanoparticles remove heavy calcification. EDTA-loaded nanoparticles that specifically target degraded elastin reversed existing heavy mineral deposits in arteries, as per elemental calcium analysis (124.161±34.410 µg Ca per mg of the dry aorta in Blank-HSA-El-Ab NPs vs. 100.520±19.131 µg in EDTA-HSA-El-Ab NPs group, P=0.04) and microCT (object volume, 129.001±37.785 vs. 29.815±24.169 mm3, P=0.0005). The reversal of aortic calcification was accompanied by a significant reduction of bone-associated mRNA expression of BMP2 and RUNX2 (P=0.01). Immunohistochemistry studies corroborated RT-PCR results, showing a reduction of BMP2 and RUNX2 stains in the vessel wall. The rat aortic ring culture study also showed similar results, where osteogenic genes (BMP2, RUNX2) and proteins (BMP2, RUNX2, TNAP) were suppressed upon reversal of calcification with EDTA (P=0.001). We also show ex vivo reversal of human femoral artery calcification by microCT (calcium intensity: untreated, 57.721±28.551 vs. day 6 of treatment, 5.441±3.615, P=0.01) by EDTA nanoparticle therapy. This is the first study showing the removal of calcium from heavily calcified arteries by using intravenous targeted EDTA therapy. Such therapy also reversed vascular smooth muscle cell osteoblastic transition and apoptosis in the arterial tissue, thereby potentially creating an environment for suitable tissue repair.

Calcium-dependent HLA-DQ epitope revealed by EDTA mediated inhibition of antibody reactions in the Luminex single antigen bead assay.

Complement mediated interference with the detection of antibodies targeting HLA is a known limitation of the single antigen bead (SAB) Luminex assay. Ethylenediaminetetraacetic acid (EDTA) is currently the serum treatment of choice in most histocompatibility laboratories to block complement activation by chelating calcium. The purpose of this study was to investigate a serum with an antibody reactivity to HLA-DQ6, 7, 8 and 9 molecules, in the Luminex SAB assay, that was inhibited by treatment with EDTA. Serum was from a 55-year-old highly sensitised female renal transplant candidate that contained, among others, antibodies to an epitope containing the 74EL eplet, shared by HLA-DQ6, DQ7, DQ8 and DQ9 molecules. Serum samples were treated with EDTA, dithiothreitol (DTT), or heat prior to testing by SAB assay. EDTA-treated serum was also tested after the addition of calcium chloride (CaCl2). HLA-DQ-specific antibodies were isolated by adsorption/elution method using three informative donor cells and were tested in the absence or presence of EDTA. The antibody reactivity against HLA-DQ6, DQ7, DQ8 and DQ9 in the SAB assay was significantly inhibited by treating serum and eluates with EDTA and was restored by addition of CaCl2. The study represents the first description of a calcium-dependent epitope in HLA molecules. The relevance of this finding is that the treatment of sera with EDTA could lead to false-negative reactions in the SAB assay, which may compromise virtual crossmatching.

Lewis-base ligand-reshaped interfacial hydrogen-bond network boosts CO2 electrolysis.

Both the catalyst and electrolyte strongly impact the performance of CO2 electrolysis. Despite substantial progress in catalysts, it remains highly challenging to tailor electrolyte compositions and understand their functions at the catalyst interface. Here, we report that the ethylenediaminetetraacetic acid (EDTA) and its analogs, featuring strong Lewis acid-base interaction with metal cations, are selected as electrolyte additives to reshape the catalyst-electrolyte interface for promoting CO2 electrolysis. Mechanistic studies reveal that EDTA molecules are dynamically assembled toward interface regions in response to bias potential due to strong Lewis acid-base interaction of EDTA4--K+. As a result, the original hydrogen-bond network among interfacial H2O is disrupted, and a hydrogen-bond gap layer at the electrified interface is established. The EDTA-reshaped K+ solvation structure promotes the protonation of *CO2 to *COOH and suppressing *H2O dissociation to *H, thereby boosting the co-electrolysis of CO2 and H2O toward carbon-based products. In particular, when 5mM of EDTA is added into the electrolytes, the Faradaic efficiency of CO on the commercial Ag nanoparticle catalyst is increased from 57.0% to 90.0% at an industry-relevant current density of 500mA cm-2. More importantly, the Lewis-base ligand-reshaped interface allows a range of catalysts (Ag, Zn, Pd, Bi, Sn, and Cu) to deliver substantially increased selectivity of carbon-based products in both H-type and flow-type electrolysis cells.

Seroprevalence of Hepatitis B Infection Among Blood Donors in a Tribal-Preponderant State of India: A Seven-Year Retrospective Observational Study.

Background Blood transfusion is an essential and lifesaving procedure for many acute and chronic diseases. Though saving millions of lives, it carries the risk of transfusion of transfusion-transmitted infections (TTIs), including hepatitis B. Detection of this infection prior to transfusion saves potentially vulnerable patients from an additional burden andprevents the further spread of disease. Aim and objectives Our present study aimed to determine the seroprevalence of hepatitis B virus (HBV) in blood donors at the Rajendra Institute of Medical Sciences(RIMS) in Jharkhand, a tribal-preponderant state of India. Materials and methods After obtaining approval from the institutional ethics committee, a retrospective observational study was conducted amongthe eligible blood donors visiting RIMS from April 2016 to March 2023. A total of 195,507 subjects were included in the study. All blood donation samples collected in ethylenediaminetetraacetic acid (EDTA) vials were tested for five TTIs: human immunodeficiency virus 1 and 2, HBV, hepatitis C virus (HCV),malaria and syphilis. HBV testing was conducted via chemiluminescence technique to check f or the presence of hepatitis B surface antigen (HBsAg) in plasma. Results Among the study sample of 195,507 donors, theprevalence of HBsAg positivity was 0.87%. Among all the TTIs, more than 50% (51.93%) were HBsAg positive. The positivity percentage was higher in male donors and HBsAg positivity rose with an increase in replacement donors. Conclusions HBV is a major health concern in developing countries such as India due to its high endemicity. Therefore, early detection of HBV carriers in the blood donor population helps in curbing the spread of further infection and it also helps policymakers to develop different health programs to reduce further incidence ofthe infection in the general population.

Ion chromatography-pulsed amperometry method for determination of trace hydrogen sulfide in air

Hydrogen sulfide (H2S) is a pervasive gaseous pollutant that emits the characteristic odor of rotten gas, even at low concentrations. It is generated during various industrial processes, including petroleum and natural gas refining, mining operations, wastewater treatment activities, and refuse disposal practices. According to statistics from the World Health Organization (WHO), over 70 occupations are exposed to H2S, rendering it a key monitoring factor in occupational disease detection. Although H2S has legitimate uses in the chemical, medical, and other fields, prolonged exposure to this gas can cause severe damage to the respiratory and central nervous systems, as well as other organs in the human body. Moreover, the substantial release of H2S into the environment can lead to significant pollution. This noxious substance has the potential to impair soil, water, and air quality, while disrupting the equilibrium of the surrounding ecosystems. Therefore, sulfide has become one of the most commonly measured substances for environmental monitoring worldwide. Achieving the stable enrichment and accurate detection of low-level H2S is of great significance. Common methods for detecting this gas include spectrophotometry, chemical analysis, gas chromatography, rapid field detection, and ion chromatography. Although these methods provide relatively reliable results, they suffer from limitations such as high detection cost, low recovery, lack of environmental friendliness, and imprecise quantification of low-concentration H2S. Furthermore, the sampling processes involved in these methods are complex and require specialized equipment and electrical devices. Additionally, approximately 20% of the sulfides in a sample are lost after 2 h in a conventional alkaline sodium hydroxide solution, causing difficulties in preservation and detection. In this study, an accurate, efficient, and cost-saving method based on ion chromatography-pulse amperometry was developed for H2S determination. A conventional IonPac AS7 (250 mm×4 mm) anion-exchange column was employed, and a new eluent based on sodium hydroxide and sodium oxalate was used to replace the original sodium hydroxide-sodium acetate eluent. The main factors influencing the separation and detection performance of the proposed method, including the pulse amperage detection potential parameters and integration time, as well as the type and content of additives in the stabilizing solution, were optimized. The results showed that the proposed method had a good linear relationship between 10 and 3000 μg/L, with correlation coefficients (r2) of up to 0.999. The limits of detection (S/N=3) and quantification (S/N=10) were 1.53 and 5.10 μg/L, respectively. The relative standard deviations (RSDs) of the peak area and retention time of sulfides were less than 0.2% (n=6). The new method exhibited excellent stability, with up to 90% reduction in reagent costs. Compared with conventional ion chromatography-pulse amperometry, this method is more suitable for detecting low concentrations of sulfides in actual samples. Sulfides in a 250 mmol/L sodium hydroxide-0.8% (mass fraction) ethylenediaminetetraacetic acid disodium salt solution were effectively maintained for over 10 h. The new stabilizer significantly improved the reliability of both large-scale and long-term detection. The recovery of the proposed method was investigated by combining the system with a badge-type passive sampler. This sampling method requires no power devices; it is inexpensive, simple to operate, and can realize long-term sampling without the need for skilled personnel. Moreover, it can overcome the influence of short-term changes in pollutant concentration. The sampling results have high reference value for large-scale intervention-less pollutant monitoring in ultraclean rooms, museum counters, and other places. The results demonstrated that the recovery of the proposed method was greater than 95% for the blank sample and 80% for the sample plus standard solution. Finally, the newly established method was applied to determine H2S levels in air samples collected via passive sampling at school garbage stations. The measured results did not exceed the national limit.

N-Formylation of Carbon Dioxide and Amines with EDTA as a Recyclable Catalyst under Ambient Conditions

The reduction of CO2 is an important method to produce chemicals such as methanol, formic acid, formaldehyde, etc. In general, the reduction of CO2 is carried out at high temperatures and pressures with precious metals as catalysts, which is not favorable for industrial procedures. Thus, it will be very useful if researchers can find cost-effective catalysts for industrial application in CO2 reduction. In this work, commercially available ethylenediaminetetraacetic acid (EDTA) was tested as a cheap, non-toxic, and recyclable catalyst to initiate the N-carbonylation reaction of CO2 with amines. After screening various reaction parameters, including temperature, pressure, time, solvent, and reducing agent, the optimal reaction conditions were obtained: 80 °C, 2 MPa, 6 h, 50 mmol% catalyst dosage, 1 mL DMSO, and 1:1 molar ratio of amine to reducing agent. Notably, further studies confirmed that EDTA could also be effective for N-formylation even under ambient conditions (0.1 MPa and room temperature). The suitability of the catalyst for 26 kinds of substrates (including aliphatic amines, aromatic amines, and alicyclic amines) and its reusability were also investigated, with satisfactory results. Scale-up research has been performed effectively with a high conversion of amine (83%) to obtain the mono-formylated product selectively. Finally, the mechanism of the reaction between amine and CO2 has been proposed via control experiments and compared with results in the literature.

Assessing Micronutrients in Soil with a New Chemical Extractant Using Isotopic Dilution Techniques: Linkages to Labile Fractions in Soil

ABSTRACT With the purpose of economizing the routine soil testing for micronutrients and avoiding the use of multiple soil extraction procedures, a laboratory investigation was attempted to evaluate a new chemical extractant for assessing the availability of common micronutrients (Fe, Cu, Mn, Zn, Mo, and B) in soils of widely varying properties (n = 32). The new extractant designated as OM-MES-VERA# contained 0.01 M oxalic acid, 0.02 M maleic acid, 0.02 M 2-(N-Morpholino) ethane sulfonic acid (MES), 0.0025 M ethylene diamine tetraacetic acid di-sodium salt, 0.02 M acetic acid, and 0.1% polyacrylamide (final pH adjusted to 6.0). OM-MES-VERA extracted significantly higher amounts of micronutrient cations and B from soils compared to the conventional diethylene triamine pentaacetic acid (DTPA, pH 7.3) extractable micronutrient cations and hot water soluble B, respectively, but lesser amount of Mo compared to Mehlich-3 universal extractant. Soil test values by both OM-MES-VERA- and conventional extractants were correlated with soil properties. The labile (E and L) values of micronutrient cations and Mo estimated by isotopic dilution method, ammonium bicarbonate-DTPA, pH 7.6 extractable soil B (as an estimate of E for B) and B concentration in maize (as an estimate of L for B) were successfully regressed on soil test values of micronutrients by OM-MES-VERA and conventional soil extractants except in the case of DTPA (pH 7.3) for E-value of Fe and L-value of Mn. The OM-MES-VERA extractant can be considered to assess the availability of common micronutrients in soils of diverse soil properties.

Accelerated de-chelation of EDTA-metal complexes: A novel and versatile approach for wastewater and solid waste remediation

Industrial waste, including wastewater and solid waste, often contains toxic heavy metals that necessitate extraction and separation prior to safe disposal or reusing them. Sewage sludge incineration ash (SSIA), a non-incinerable waste, holds significant amounts of heavy metals such as iron, zinc, copper, nickel, chromium, and lead. Recovery and reuse of heavy metals from SSIA and further application of treated SSIA sludge remain challenging. Ethylenediaminetetraacetic acid (EDTA) is widely used for heavy metals chelation in different applications. While its chelation with heavy metals is rapid and easy to achieve, the de-chelation of the metal complexes is otherwise slow (∼3 days) and challenging due to their high stability constants. In this study, we investigate the recovery of heavy metals from SSIA through chelation using EDTA, and develop, for the first time, a method to rapidly de-chelate the EDTA-metal complexes through the facile chilling process (1 – 3 h) that accelerates the separation of EDTA and metal ions. A sequential precipitation of high-purity heavy metals from the EDTA-metal complexes was demonstrated with and without de-chelation. This novel and versatile method allows the separation of many valuable compounds from the treated SSIA, including regenerated EDTA, potassium hexafluorosilicate, iron phosphate, iron(III) hydroxide, iron silicate, titanium phosphate, calcium phosphate, copper(I) thiocyanate, nickel bis(dimethylglyoximate), lead(II) sulfate, and zinc sulfide. This approach opens doors for more sustainable waste management and the recovery of valuable resources from industrial waste.

Serial Nitrogen-Doped Metal/Carbon Composites Derived from Organic Salts for Superior Electromagnetic Wave Absorption and Supercapacitor Electrode.

The present study provides a facile one-pot pyrolysis strategy to prepare serial nitrogen-doped (N-doped) metal/carbon composites derived from six types of metal ethylenediaminetetraacetic acid (EDTA-M, M = Co, Cu, Mn, Fe, Mg, and Ca). N-doped Co/C composite integrated carbonaceous with magnetic components to attain dielectric-magnetic double loss mechanisms. The minimum reflection loss and effective absorption bandwidth reached -57.6 dB at 1.75 mm and 4.64 GHz at 1.52 mm, respectively. The electromagnetic simulation further confirms that the dissipation ability increases with the improvement of carbonization temperature. Results show that altering the metal species of precursors can significantly improve the electrochemical performance of the composites using the identical strategy. N-doped Cu/C composite performed a maximum specific capacitance of 2383.3 F g-1 at 0.5 A g-1 -1, and maintained 86.3% cycling stability at 20 A g-1 after 5000 cycles. The energy density of a symmetrical two-electrode configuration achieved 350.13 Wh kg-1 at a power density of 4000.04 W kg-1. Density functional theory calculations indicate that nitrogen dopants cause faster ion transport and stronger adsorption capacity. Moreover, the bifunctionality of other composites types are also systematically characterized.

Optimising Bioprinting Nozzles through Computational Modelling and Design of Experiments.

3D bioprinting is a promising technique for creating artificial tissues and organs. One of the main challenges of bioprinting is cell damage, due to high pressures and tensions. During the biofabrication process, extrusion bioprinting usually results in low cell viability, typically ranging from 40% to 80%, although better printing performance with higher cell viability can be achieved by optimising the experimental design and operating conditions, with nozzle geometry being a key factor. This article presents a review of studies that have used computational fluid dynamics (CFD) to optimise nozzle geometry. They show that the optimal ranges for diameter and length are 0.2 mm to 1 mm and 8 mm to 10 mm, respectively. In addition, it is recommended that the nozzle should have an internal angle of 20 to 30 degrees, an internal coating of ethylenediaminetetraacetic acid (EDTA), and a shear stress of less than 10 kPa. In addition, a design of experiments technique to obtain an optimal 3D bioprinting configuration for a bioink is also presented. This experimental design would identify bioprinting conditions that minimise cell damage and improve the viability of the printed cells.