EDTA Complex Research Articles

The effect of different extractants on lead desorption from a natural mineral

Natural minerals, such as quartz, clinoptilolite and calcite, are useful as sorbents for various applications, but their content of heavy metals ions is the most problematic obstacle to their application. Before their (re)use, the minerals must be purified. In this work, the subject was desorption of lead from a natural multi-component mineral sample consisting of a mixture of silicates (mainly quartz and clinoptilolite) and calcite formations. Besides deionized water, different extraction solutions were tested: NaCl, KCl, CaCl2, MgCl2, HCl, HNO3, EDTA, EDTA/HCl, EDTA/NaOAc–HOAc, HOAc, NaOAc and NaOAc–HOAc. Several parameters were varied in order to obtain the optimal conditions for the desorption process: the concentration of the extraction solution, the ratio of the mass of the sample and volume of the extractant, and the pH value of the suspension. The best purification effect in one desorption cycle was obtained when 0.1M EDTA, at a pH value of 3.5 (0.2M EDTA was mixed with 0.01M acetic buffer, at pH value 3.0, in ratio 1:1) was applied. Sequential extraction (5 consecutive iterations) was performed to provide a more efficient purification process. The lead content (58.20mg/kg) was decreased by: 20% (using HOAc), 21% (using EDTA) and by more than 50% (using EDTA/NaOAc–HOAc). The pH value and conductivity were measured at all critical points to clarify the mechanism of the desorption process. The formation of Pb–EDTA complex is the result of two parallel phenomena, complexing and ion-exchange. An enhanced adsorption capacity and an improved microelement profile for the purified samples were also attained. The mineralogical and radiochemical performances of the sample were determined by the X-ray diffraction and gamma spectrometry techniques. Microelement analyses of the native and purified samples were performed by inductively coupled plasma optical emission spectroscopy (ICP-OES).

Assessment of the Fe<sup>3+</sup>-EDTA Complex in UV-Fenton-Like Processes: The Degradation of Methylene Blue

This study investigated the effect of ultraviolet (UV) enhancement and the Fe3+-EDTA Complex on the degradation of methylene blue (MB) in Fenton-like system. By studying different variables including H2O2concentration, Fe3+-EDTA concentration and pH value，and using MB as a model pollutant, the best experimental conditions was to investigated. Experimental results showed that it is possible to degrade MB wastewater effectively by modified UV-Fenton with Fe3+-EDTA at neutral pH. Besides, optimality condition (pH= 7, [Fe3+-EDTA] = 2 mmol/L, [H2O2] = 10 mmol/L) which were used in the modified UV-Fenton that achieves a removal of over 95% of the MB in 60 min reaction time. Therefore, this new modified Fenton system is an effective treatment for MB wastewater.

Applied Kinetics Aspects of Ferric EDTA Complex Reduction with Metal Powder

Nitrogen and sulfur oxides (NOx and SOx) emitted from fossil-fuel-fired facilities can be simultaneously absorbed into aqueous mixed solutions of sulfite and FeIIL, a ferrous ion coordinated to a ligand L (a chelate compound). Usually, the ligand L represents an anion of ethylenediaminetetraacetic acid (EDTA or edta). Nitrogen oxide (NO) sparingly soluble in water is promptly bound to the [FeII(edta)(H2O)]2– complex to form the [FeII(edta)(NO]2–compound. However, [FeII(edta)(H2O]2– chelate is oxidized to form [FeIII(edta)(H2O)]− by NO, NO2, and O2, normally coexisting in flue gases. Because the ferric complex does not react with NO, the suppression of these undesired oxidation processes is a very important technological problem to be overcome. Thus, in this work, the reduction kinetics of ferric ion by metal was discussed on the basis of the kinetic data regarding the ferric ion reduction in aqueous solutions of [FeIII(edta)(H2O)]− containing such pulverized metals as aluminum, tin, and zinc. The rate exp...

Secrets of solid state and aqueous solution structures of [Ni(tmdta)](2-).

The molecular structures of Li2[Ni(tmdta)]·5H2O (1a, tmdta = trimethylenediaminetetraacetate), {C(NH2)3}2[Ni(tmdta)]·6H2O (1b), and {Ni(H2O)6}[Ni(tmdta)]·2H2O (2a) have been determined. The central trimethylenediamine chelate ring shows half-chair (hc) geometries in 1a and 1b, while a twist-boat (tb) conformation is encountered in 2a. The coexistence of tb and hc forms in the solid state prompted us to elucidate the existence of a tb ⇌ hc equilibrium in aqueous solution. Evaluation of the data from solid state vibrational spectra (Raman and IR) for the hc and tb forms showed excellent agreement with simulated spectra obtained with DFT computations (TPSSh/TZVP). This outstanding matching between theory and experiment enabled us to build composite spectra with varying hc:tb ratios. Comparison of these results with Raman and IR spectra recorded for [Ni(tmdta)](2-) in aqueous solution revealed that simulated Raman and IR spectra with a hc:tb ratio = 2:3 match the solution spectra in an accurate way. This equilibrium ratio enabled us to compute (13)C NMR sifts for the paramagnetic solution spectrum of [Ni(tmdta)](2-) based on the relative contributions by hc and tb fractions. This leads to computed shifts that agree closely with the experimental ones. Also, the kinetics of the skeleton dynamics could be estimated quantitatively by temperature-dependent (13)C NMR spectroscopic measurements. An interesting effect encountered for the very first time here concerns a drastic intensity difference of the 10Dq band ((3)A2g → (3)T2g(F) transition) in solid state electronic spectra of tb vs hc isomers, where the intensity of this band in the case of the hc form is much lower than that of the tb conformer and thus more similar to the case of the usual Ni(II) chromophore in octahedral environment. The equilibrium constants for complex formation and protonation of Ni(II)-tmdta at low pH have been estimated by pH-dependent UV-vis titration experiments. Correlation of these data with those of Ni(II)-edta and related 3d M(II) edta and tmdta complexes allow important conclusions on the consequences resulting from extending the central diamine ring in the ligand by one methylene group in terms of both complex and protolytic stability for edta vs tmdta complexes.

Identification of proteinaceous binding media for the polychrome terracotta army of Emperor Qin Shihuang by MALDI-TOF-MS

A proteinaceous binding media for the polychrome terracotta army of Emperor Qin Shihuang has been identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Methods for the preparation of the model samples and the elimination of interferences have been evaluated, as well as ageing processes. A method involving the complexation of EDTA in combination with dialysis was used to eliminate any interference in the polychrome layers taken from the historical samples. The model samples were aged by being buried in loess to replicate the ageing process of the historical samples as closely as possible. The optimum conditions for the extraction and subsequent enzymatic hydrolysis of the extracted protein were investigated. Under the optimized conditions, the "peptide mass fingerprints" of the proteinaceous binding media from the historical and model samples were determined by MALDITOF-MS. The results revealed that animal glue was used as the binding media for the polychrome layers of Emperor Qin Shihuang's terracotta army. It also shows that animal glue used as binding media has a long history in China.

Novel active carbon/crown ether derivative hybrid material for the selective removal of Cu(II) ions: The crucial role of the surface chemical functions

The selective elimination of metal ions from solution is a subject of large interest from both theoretical and practical points of view. For this purpose it is desirable to have solid materials having specific functions able of capturing the ions. This paper reports the preparation of a crown ether derivative/active carbon hybrid material and the application for the selective elimination of Cu(II). The hybrid material has been prepared by adsorption of the crown ether derivative N-2-(4-amino-1,6-dihydro-1-methyl-5-nitroso-6-oxopyrimidinyl)-15-crown-5 (HL) onto an activated carbon (Merck). This adsorption process is not dependent on the pH and it is highly irreversible due to strong π–π interactions between the arene centers of the activated carbon and the pyrimidine moiety of HL. This means that the pyrimidine groups of HL are blocked on the surface of the activated carbon due to the adsorption while the 15-crown-5 ether functions remain ready for coordination of metal ions. Thus, the Merck/HL hybrid has a much larger adsorption capacity of Cu(II) than this of the unfunctionalized activated carbon. In addition, the adsorption of Cu(II) ions in the presence of K(I) and Ca(II) is highly selective. It is shown that this selectivity for Cu(II) is related to the size of the 15-crown-5 ether cavity is very appropriate to house this ion. The desorption of Cu(II) from the loaded Merck/HL hybrid material in the presence of EDTA allows the regeneration of most of the actives sites of the hybrid due to the formation of the more stable Cu(II)–EDTA complex. This paper also reports the preparation of HL, its behavior in aqueous solution, its complexing behavior and its adsorption on the active carbon. These studies are the cornerstones to explain the behavior of the Merck/HL hybrid material in the adsorption of Cu(II).

Mechanism of the oxidation of thiosulfate with hydrogen peroxide catalyzed by aqua-ethylenediaminetetraacetatoruthenium(III)

Catalytic ability of [RuIII(edta)(H2O)]− (edta4−=ethylenediaminetetraacetate) complex toward oxidation of thiosulfate (S2O32−) in presence of H2O2 has been explored in the present work. The kinetics of the catalytic oxidation of thiosulfate (S2O32−) has been studied spectrophotometrically as a function of [RuIII(edta)], [H2O2], [S2O32−] and pH. Spectral analyses and kinetic data indicate a catalytic pathway involving activation of both substrate (S2O32−) and oxidant (H2O2). Substrate activation pathway involves the formation of a red [RuIII(edta)(S2O3)]3− species through the reaction of the [RuIII(edta)(H2O)]− catalyst complex and the substrate (S2O32−). Hydrogen peroxide reacts directly with thiosulfate coordinated to the RuIII(edta) complex to yield sulfite as immediate oxidation product. Peroxide activation pathway is governed by the formation of [RuV(edta)(O)]− catalytic intermediate which oxidize thiosulfate, however, at slower rate (kox2=0.012 M−1 s−1 at 25°C) as compared to the rate of oxidation of the coordinated thiosulfate (kox1=0.93 M−1 s−1 at 25°C). Sulfite and sulfate were found to be the oxidation products of the above described catalytic oxidation process. A detailed mechanism in agreement with the spectral and kinetic data is presented.

Nanoscale zero-valent iron for the removal of Zn2 +, Zn(II)–EDTA and Zn(II)–citrate from aqueous solutions

The parameters which influence the removal of different zinc (Zn) species: Zn2+, Zn(II)–EDTA and Zn(II)–citrate from aqueous solutions by nanoparticles of zero-valent iron (nZVI) were investigated at environmental relevant pH values. Untreated, surface modified and silica-fume supported nZVI were applied at different iron loads and contact times to Zn solutions, which were buffered to pH5.3, 6.0 and 7.0. The results revealed that pH, the type of nZVI, the iron load, the contact time, and the Zn species all had a significant influence on the efficiency of removal. Zn2+, Zn(II)–EDTA and Zn(II)–citrate were the most effectively removed from aqueous solutions by untreated nZVI. Zn2+ removal was governed mainly by adsorption onto precipitated iron oxides. Complete removal of Zn2+ and Zn(II)–citrate was obtained at all pH values investigated. The removal of strong Zn(II)–EDTA complex was successful only at acidic pH, which favored degradation of Zn(II)–EDTA. Consequently, the released Zn2+ was completely removed from the solution by adsorption onto iron oxides.

DEVELOPMENT OF A FLOW INJECTION ANALYSIS SYSTEM EMPLOYNG ALTERNATIVE AND LOW-COST MATERIALS FOR DIDACTIC PURPOSES

This work describes a simple and inexpensive flow injection analysis system in which gravity force provides fluid propulsion while needles for insulin administration or metallic wires act as electrodes for amperometric detection. The proposed system was able to demonstrate the influence of several operational parameters on the transient signals. Moreover, this system was successfully used to evaluate both the stoichiometry of Cu2+-EDTA complex and the effect of pH on the kinetics of the reaction between ferricyanide and ascorbic acid. Therefore, the proposed system can be regarded as an efficient and accessible didactic tool for the teaching of FIA principles.

Investigating Pseudomonas putida–Candida humicola Interactions as Affected by Chelate Fe(III) in Soil

Microcalorimetric technique was applied to assess the toxic effect of EDTA-chelated trivalent iron on Pseudomonas putida (P. putida) (bacterium), Candida humicola (C. humicola) (fungus) and their mixture in sterilized soil. Microbial growth rate constant k, total heat evolution Q T, metabolic enthalpy ∆H met, mass specific heat rate J Q/S, microbial biomass C and inhibitory ratio I were calculated. Results showed that microcalorimetric indexes decreased with the increasing Fe(III)-EDTA complex concentration. Comparing the single and mixed strains, the effect of Fe(III) on bacterium-fungus interaction was dominant at lower dose, whereas, the metal toxicity at high dose of Fe was the main factor affecting P. putida and C. humicola activity. Thus, the mixture had moderate tolerance to the iron overload, and exhibit synergistic interaction in exponential growth phase (0-0.3 mg g(-1)). The results of glucose degradation showed that glucose was consumed totally at the end of exponential phase of microbial growth.

Effect of EDTA on the diffusion behavior of 99TcO4 − and ReO4 − in GMZ bentonite

Polyaminopolycarboxylate EDTA with powerful metal-binding property, which often presents in low and intermediate-level waste, can enhance the radionuclide migration. The effect of EDTA on the diffusion behavior of 99TcO4 − and ReO4 − in Gaomiaozi (GMZ) bentonite was investigated by using through-diffusion method. For 99TcO4 − in present of EDTA, the D e values was (1.2 ± 0.1) × 10−11 m2/s, which was 4 times higher than that in absent of EDTA. It can be explained that the complexation between 99TcO4 − and EDTA might be formed. By contrast, the D e values of ReO4 − remained unchanged in present or absent of EDTA, indicating that ReO4 − could not complex with EDTA. However, the diffusion of ReO4 − could be increased in present of EDTA, the D a value was found to be increased from 1.8 × 10−10 to 5.4 × 10−10 m2/s. It demonstrated that ReO4 − need more drastic conditions to form the Re(VII)–EDTA complexes than those used for 99TcO4 −. For both ReO4 − and 99TcO4 −, the rock capacity factor α is less than the total porosity e tot, indicating that they has little retention/sorption on the surface of bentonite.

The influence of homogeneous electrolyte composition on microplasma synthesis and characteristics of Fe-containing coatings on A1050 alloy

In this study the influence of the iron complexes and sodium metasilicate concentrations on the microstructure, thickness and total iron content in the microplasma coatings are reported. The microplasma synthesis of iron containing coatings on A1050 aluminum alloy at the alternative current is able to be controlled by the electrolyte composition variation. The coatings were obtained in electrolytes within the range of concentrations 0–0.05M for sodium metasilicate and 0.01–0.04M for iron EDTA complexes. The synthesis process was studied by the analysis of the anodic and cathodic voltage–time curves behavior, chemical composition of the coatings, their thickness and phase composition.

Modeling of the effect of EDTA on copper(II) biosorption onto Posidonia oceanica waste in batch and fixed-bed systems

The performance of Posidonia oceanica for copper(II) biosorption in the presence of EDTA was investigated in batch and column experiments. In batch mode, copper(II) uptake in the presence of EDTA was lower than in its absence for the pH range 1.5–6.0. The decrease in the copper(II) uptake, attributed to the change in the chemical speciation of copper(II) with EDTA in solution, was from 71.7 to 58.8mg/g in the absence and presence of EDTA respectively at pH 6. Column experiments were carried out at 5 and 20mg Cu(II)/dm3 and different doses of EDTA. Constant copper(II) leaks were detected in the effluent of the columns. Leak concentrations matched the copper(II)-EDTA complexes’ concentration in the feed solution. Copper(II)-EDTA complexes were retained in neither batch nor continuous mode. A technological approach to solve this limitation was adopted: a dual biosorption system with P. oceanica and Scharlau AC in serial column configuration was investigated with promising results. Final effluent free of copper(II) was obtained since the copper(II)-EDTA leak was removed by the Scharlau AC. Copper(II) biosorption dynamics in fixed-bed column in the presence of EDTA were modeled by coupling the mass transport process with the chemical equilibrium between copper(II) and EDTA.

Valve based on novel hydrogels: From synthesis to application

New hydrogels as materials with potential application in the area of actuators have been developed. Hydrogel synthesis was performed using tris[(hydroxymethyl) methyl]acrylamide (NAT) and itaconic acid (ITA) as monomers and (+)N,N′-diallyltartradiamide (DAT) as crosslinker. The hydrogels NAT–ITA were prepared using different molar fraction of monomers and characterized by FTIR-ATR, rheology, swelling properties and mechanical force. The hydrogel prepared with 80% and 20% of NAT and ITA, respectively, has the lowest equilibrium swelling ratio (ESR=16) in water but the highest elastic modulus (10±1kPa) and strength (2.2±0.1Nh−1). The gel strength increased 0.5N in a half hour, while the volume increased 4 times when passed from an acid medium to a basic medium. This hydrogel was chosen to prepare a pH-sensitive valve to control the flux in a capillary tube. The valve was tested using a system to control the formation of Fe3+–EDTA complex. The response time was 3 and 15min to open and close the valve, respectively. The flow of the solution through the valve was 11μLmin−1. The pressure of the solution during the closing of the valve was 10kPa. The continuous opening and closing of the valve involves repetitive expansion and collapse of the network that could damage the structure of the network. However, the valve produced a reproducible and stable response. The dynamic hydrogen bonding existing in the polymeric chains of NAT–ITA products could assist in the reversible process when the hydrogels were subjected to repetitive work. The mechanical properties of the gels and self-healing capacity of the networks indicated that the products could be applicable in the development of systems for controlled drug release.

Characterisation of Ternary Complex Formation Between [RuIII(edta)]– and Various Bidentate Ligands

AbstractSpeciations of ruthenium(III)‐edta complexes of bidentate (O, O) (N, O) and (S, O) donor type ligands were determined by pH‐potentiometry and UV/Vis spectrophotometry in aqueous solution. Complexes of [RuIII(edtaHx)L]2– (x = 0, 1, 2 and 3) stoichiometry were only formed and the fully deprotonated species dominate at the physiological pH 7.4. Protonation occurs at the free carboxylate arms of edta; when x = 3 one of the coordination positions of the RuIII becomes free. Formation of protonated ternary complexes are more characteristic for ligands with (N, O) and (S, O) donor sets where the complex formation started (ligands with (N, O) donor set) or completed (ligands with (S, O) donor set) already at pH 2. In acidic conditions the stability order of the complexes follows the (O, O) < (N, O) < (S, O) sequence, which changes slightly for the physiological pH 7.4: (O, O) ≈ (N, O) < (S, O). The complexes formed were characterised also by LNT EPR spectroscopy. The kinetics of the ligand exchange between ternary complexes at pH 6 was found to be dissociative. The reaction rate follows basically the stability order: (O, O) < (N, O) < (S, O). No side reactions were found when the ligands replaced had (O, O) donor set; but formation of [RuIII(edta)(L1),(L2)]3– was hypothesised in the case of ligands with (N, O) or (S, O) donor sets.

Evaluation of the double‐disk synergy test for New Delhi metallo‐β‐lactamase‐1 and other metallo‐β‐lactamase producing gram‐negative bacteria by using metal‐ethylenediaminetetraacetic acid complexes

New Delhi metallo-β-lactamase-1 (NDM-1), one of the metallo-β-lactamases (MBLs), has been identified from clinical isolates worldwide. Rapid detection of NDM-1 producers is necessary to prevent their dissemination. Seven types of EDTA complexes were evaluated as MBL inhibitors in double-disk synergy tests (DDSTs), resulting in detection of the first isolate of NDM-1-producing Escherichia coli (NDM-1 Dok01) in Japan. NDM-1 Dok01 was detected when EDTA magnesium disodium salt tetrahydrate (Mg-EDTA), EDTA calcium disodium salt dihydrate, EDTA cobalt disodium salt tetrahydrate and EDTA copper disodium salt tetrahydrate were used as MBL inhibitors. The sensitivity and specificity of DDSTs using Mg-EDTA for 75 MBL producers and 25 non-MBL producers were 96.0% and 100%, respectively. These findings indicate that the DDST method using Mg-EDTA can detect MBL-producing strains, including NDM-1 producers.

Binding of aquo-ethylenediaminetetraacetatoruthenium(III) to apo-transferrin. Fluorescence, antiproliferative and in silico studies

The interaction of a RuIII(edta) complex (edta4−=ethylenediaminetetraacetate) with human apo-transferrin (apo-hTf) has been investigated using fluorescence spectroscopic techniques. The results of fluorescence spectral studies point towards static quenching involving binding of RuIII(edta) with apo-hTf. The value of the apparent binding constant (KA) estimated at physiological buffer is 4.72×104M−1. Antiproliferative activity of RuIII(edta) in MCF-7 (breast carcinoma) cells was evidened by microculture tetrazolium test (MTT). Our results taken together are suggestive of the fact that the RuIII(edta) complex can bind to apo-hTf, and induce cell death by inhibiting NF-κB activation. The results of the computational based in silico analysis studies further suggest that the RuIII(edta) that binds apo-hTf to form the [Ru-edta-hTf] complex, for which the binding of [Ru-edta-hTf] complex with transfrrin receptor (TfR) takes place not at the usual binding domain, but in the other domain of the receptor. The alteration of the binding domain of transferrin with its receptor may inactivate the observed transferrin-transferrin receptor mediated biological functions.

Analysis of proteinaceous binding media used in Tang Dynasty polychrome pottery by MALDI-TOF-MS

The proteinaceous binding media used in Tang Dynasty polychrome pottery was determined using matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS). The optimum conditions for the extraction and subsequent enzymatic hydrolysis of the protein sample were established, and applied to the pretreatment of model and historical samples. Complexation of EDTA in combination with dialysis was determined to be the most effective method for eliminating interferences in polychrome layers taken from historical samples. Model samples were aged by burial in loess so as to more closely replicate the ageing process of the historical samples. Using the aforementioned optimized conditions, the “peptide mass fingerprint” of the binding media of historical and model samples was determined by MALDI-TOF-MS. Comparisons between the “peptide mass fingerprint” obtained for the historical sample and those of the model samples proved that animal glue was used as the binding media for the Tang Dynasty polychrome pottery. It also shows that animal glue used as binding media enjoys a long history in China.

Indirect Competitive Immunoassay for Mercury Ion Determination Using Polyclonal Antibody Against the Hg-GSH Complex

Hg is a highly toxic heavy metal in the environment. Detection and quantification of Hg plays an important role in the study of environmental contamination with this metal. A polyclonal antibody that recognizes Hg-ethylenediamine-N,N,N′,N′-tetraacetic acid (EDTA) was produced by immunizing the New Zealand white rabbit with Hg conjugated to bovine serum albumin (BSA) via a bifunctional chelator, glutathione (GSH), and the resulting antiserum was screened through indirect noncompetitive enzyme-linked immunosorbent assay (ELISA) using GSH-ovalbumin (OVA) and Hg-GSH-OVA. The polyclonal antibody displayed high levels for the relative Hg-GSH-OVA conjugate. The concentration of Hg2+was quantified based on the ability of its EDTA complexes to inhibit the binding of the goat anti-rabbit IgG conjugated with horseradish peroxidase and, subsequently, color formation in the assay. The indirect competitive ELISA was specific to Hg2+, with the lowest detection limit reaching 9.55 ng/mL. Cross-reactivities with other metals were less than 0.001% except for Cd2+, which showed a slight cross-reactivity in indirect competitive ELISA. The recoveries from deionized water were in the range of 90% to 102%. Results indicated that the ELISA based on polyclonal antibody could be a very promising analytical tool for rapid (3 to 5 hr) and sensitive determination of Hg and other metal ions in the environment. Additionally, the indirect competitive ELISA can potentially be applied in environmental forensics studies, as a sensitive and inexpensive monitoring method for environments polluted with Hg and possibly other metal ions.

High sensitive gold-nanoparticle based lateral flow Immunodevice for Cd2+ detection in drinking waters

In this work for first time a lateral flow immunosensor device (LFID) for Cd2+ determination in drinking and tap waters using the Cd–EDTA–BSA–AuNP conjugate as signal producer tool is introduced. The principle of working is based on competitive reaction between the Cd–EDTA–BSA–AuNP conjugate deposited on the conjugation pad strip and the Cd–EDTA complex formed in the analysis sample for the same binding sites of the 2A81G5 monoclonal antibody, specific to Cd–EDTA but not Cd2+ free, which is immobilized onto the test line. The device has a large response range within 0.4–2000ppb, being the linear response between 0.4 and 10ppb. The quantification and detection limits of 0.4 and 0.1ppb, respectively, represent the lowest ones reported so far for paper based metal sensors. The obtained detection limit is 50 times lower than the maximum contamination level required for drinking water. Here we also show a new option for increasing the sensibility in the LFDs with competitive format, through the decreasing in concentrations of the Cd–EDTA–BSA–AuNP conjugate deposited in the conjugation strip and the mAbs deposited in the test and control zones until to reach optimized concentrations. It is an important result take into account that the increase in sensibility is one of the challenges in the field of LFD sensors, where are focused many of the ongoing researches. In addition, a specificity study of the device for several metal interferences, where potential metal interferences are masked with the use of the EDTA and OVA optimized concentrations, is presented too.