Phosphonomethyl Iminodiacetic Acid Research Articles

Surface-modified cobalt oxide nanoparticles: new opportunities for anti-cancer drug development.

The development of smart nanoparticles that can exhibit the anti-cancer activity, introduces better efficacy and lower toxicity for treatment. The present study was aimed to evaluate the anti-cancer activity of surface functionalized CoO nanoparticles against Jurkat (T-cell lymphoma) and KB (oral carcinoma) cell lines. The nano-sized cobalt oxide nanoparticles (CoO) was prepared by thermal decomposition method followed by surface modification using phosphonomethyl iminodiacetic acid (PMIDA). The PMIDA-coated CoO nanoparticle was characterized by X-ray diffraction, dynamic light scattering, and transmission electron microscopy; and the conjugation was analyzed by Fourier transform infrared spectroscopy. The resultant nanoparticles with an average size less than 100 nm measured by dynamic light scattering and transmission electron microscopy. Cytotoxicity study, flow cytometric analysis and scanning electron micrographs have been revealed that PMIDA-coated nanoparticles significantly enhances the cellular uptake of the nanoparticle and thus facilitates apoptosis of cancer cell (Jurkat and KB). For the application of PMIDA-coated CoO nanoparticles in the medical field, doxorubicin, a potent anti-cancer drug, has been used in similar fashion in this experimental design and all these effects or patterns were observed.

COOH-functionalisation of silica particles

In this study COOH-functionalised silica is synthesised using phosphonate N-(phosphonomethyl)iminodiacetic acid (PMIDA) in an aqueous solution. The presence of PMIDA on the silica particles was verified using Fourier Transform Infrared Spectroscopy, X-ray Photoelectron Spectroscopy and titration. Experimentally, surface concentrations of COOH functional groups of up to about 3 mmol/g silica were achieved, whereas theoretical calculation of the maximum COOH functional group concentration gave about 1 mmol/g silica. The discrepancy may be caused by PMIDA multilayer formation on the particle.

A novel method for the immobilization of urease on phosphonate grafted iron oxide nanoparticle

The development of simple and reliable technique for the immobilization of enzymes is an important part of biotechnology. We demonstrate herein the modification of magnetic nanoparticles and its use in the immobilization of the urease enzyme. Magnetite particles were prepared by simple co-precipitation method in aqueous medium and then subsequently coated with phosphonomethyl iminodiacetic acid. Urease was immobilized on the magnetic nanoparticles through a carbodiimide reaction. Surface functional groups and surface composition were analyzed by Fourier transform infrared (FTIR) spectroscopy and thermo gravimetric analysis (TGA), respectively. The structural characteristics of the powders were studied by XRD. These modified nanoparticles were characterized by dynamic light scattering (DLS) and high resolution transmission electron microscopy (HRTEM). Vibration sample magnetometry (VSM) measurements showed the superparamagnetic nature of the particles at room temperature. The catalytic activity of the immobilized urease was comparable to that of the free enzyme in solution. The immobilized urease exhibited excellent catalytic activity over six times successive reuse as well as the stability. By using immobilization technique on this magnetic nanoparticle it is easy to isolate product from reaction mixture enabling to control the reaction and simultaneously lowers the cost of enzyme.

Single step surface modification of highly stable magnetic nanoparticles for purification of His-tag proteins

The aim of this study was to develop a simple, cheap, and rapid method for purification of His-tag recombinant proteins with high yields. The new immobilized metal ion affinity adsorbent containing superparamagnetic nanoparticles and hydrophilic resins are proposed here to improve the purification of His-tagged recombinant proteins. In this report, we have described the preparation of nanosized superparamagnetic nanoparticles (Fe3O4) which were prepared by chemical precipitation method followed by surface modification using phosphonomethyl iminodiacetic acid. The stable surface functionalized nanoparticles were further linked with Ni2+ for purification of 6× His-tagged proteins. The phosphonate group of the N-phosphonomethyl iminodiacetic acid ligand acts as a surface anchoring agent on magnetite nanoparticles and the remaining free –COOH groups outside for binding with Ni2+ ions. The nanoparticles were approximately 6–8 nm in size and were stable and had negligible non-specific binding for protein. The proteins were purified within 1 h and observed on sodium dodecyl sulfate-polyacrylamide electrophoresis gel.

Novel aqueous chelating agents for catalytic oxidation of hydrogen sulfide to sulfur by air

Six phosphorus-containing analogues of nitrilotriacetic acid (NTA) or ethylenedinitrilotetraacetic acid (EDTA) form stable Fe(III) complexes which have been tested as catalysts for the oxidation of hydrogen sulfide. Ligand 4, phosphonomethyliminodiacetic acid (NTAP), was found to be comparable with NTA in efficiency of catalytic activity such as the conversion of hydrogen sulfide to sulfur, half-life of ligand, consumption of ligand per kg of sulfur product. A quantitative analytical method of phosphorus-containing ligand in the absorbed solution has been successfully established by applying 31P-{1H} NMR.

Adsorption of [N-(Phosphonomethyl)imino]diacetic Acid and Iminodiacetic Acid on Poly(4-vinylpyridine)

[N-(Phosphonomethyl)imino]diacetic acid (PMIDA) and iminodiacetic acid (IDA) are two structurally similar amino acid derivatives found prevalently in a highly concentrated NaCl solution in the waste stream from the synthesis of the herbicide Roundup. Because IDA is biodegradable and PMIDA is not, it is important to be able to separate the two acids. In this work, it is shown that PMIDA and IDA have very different affinities for the basic polymer adsorbent poly(4-vinylpyridine), while NaCl has a negligible affinity. The adsorbent has been found to be robust as well as chemically and thermally regenerable. Single- and multiple-frontal column tests are used to determine equilibrium adsorption isotherms and mass-transfer parameters at temperatures between 23 and 85 °C. An Arrhenius temperature dependence is used to correlate the equilibrium adsorption data. A parallel pore and surface diffusion model can accurately describe the breakthrough and elution behavior of the high-affinity solutes, PMIDA and IDA, while a pore diffusion model can accurately describe the behavior of the nonretained solute NaCl. The models can accurately describe breakthrough behavior at temperatures between 23 and 85 °C. The data obtained in this work form the backbone for subsequent studies on batch and continuous processes for separating NaCl, IDA, and PMIDA.

A phosphate–phosphonate of titanium(IV) prepared from phosphonomethyliminodiacetic acid: characterisation, n-alkylamine intercalation and proton conductivity

A titanium(IV) phosphate–phosphonate has been prepared from phosphonomethyliminodiacetic acid [H 2O 3PCH 2N(CH 2CO 2H) 2, H 4PMIDA]. It is poorly crystalline and can be formulated as [Ti 2(PO 4)(H 2PMIDA)(HPMIDA)(H 2O)]· nH 2O, Ti(PMIDA) [P:Ti = 1.5:1; n varies with relative humidity, RH]. Carboxylic acid groups are present in the interlayer region. Sorptiometry shows the material to be non-porous. Ti(PMIDA) reacts with n-alkylamines to form intercalates and is a proton conductor with conductivity strongly dependent on RH and temperature. Observed conductivities span nine orders of magnitude ( σ 360 K =8×10 −1 S cm −1 for RH=100%).

Biodegradation of N-phosphonomethyliminodiacetic acid by microorganisms from industrial activated sludge

A microbial population that biodegraded N-phosphonomethyliminodiacetic acid (PIA), a key component of glyphosate (N-phosphonomethylglycine) process waste, was established. The stoichiometric conversion of PIA to aminomethylphosphonic acid (AMPA) was observed in a laboratory sequencing batch reactor (SBR) containing activated sludge from a glyphosate-manufacturing facility and PIA as sole source of carbon. PIA degradation was determined by high-performance liquid chromatography and confirmed by radiolabeled studies. Greater than 90% of the [carboxymethyl-2-14C]-label of PIA was released as 14CO2 in 7 days using samples of sludge from the SBR. The cycle time required to biodegrade up to 7.5 mM PIA in SBRs was reduced from 21 to < 3 days. PIA biodegradation was also established in an immobilized bacteria column inoculated with mixed liquor from a SBR; > 99% PIA removal was achieved at an influent concentration of 2.2 mM and a hydraulic retention time of < 10 h. A pure bacterial culture was isolated from a SBR by streaking samples of sludge on solid media with PIA as sole carbon source. The isolate was identified as Xanthomonas maltophilia. In liquid culture, X. maltophilia degraded up to 4.4 mM PIA within 10 days and produced stoichiometric amounts of AMPA. The results demonstrate the biodegradation of PIA and suggest the potential for its treatment in industrial biological treatment systems.

Binding of phosphonate chelating agents and pyrophosphate to apotransferrin.

Difference ultraviolet spectroscopy has been used to monitor the binding of a series of phosphonate ligands to human apotransferrin. The ligands consist of pyrophosphate as well as the phosphonic acids (aminomethyl)phosphonic acid (AMPA), (hydroxymethyl)phosphonic acid (HMP), (phosphonomethyl)-iminodiacetic acid (PIDA), N,N-bis(phosphonomethyl)glycine (DPG), and nitrilotris(methylenephosphonic acid) (NTP). Equilibrium constants have been measured for the sequential binding of two ligands per molecule of apotransferrin. In addition, site-specific equilibrium constants have been measured for the binding of AMPA, HMP, and PIDA to the vacant binding site of both forms of monoferric transferrin. Since titrations of diferric transferrin produce no difference UV spectrum, it is proposed that the primary binding site for phosphonic acids includes the protein groups that bind the synergistic bicarbonate anion that is required for formation of a stable ferric transferrin complex. It is further proposed that those ligands with two phosphonate groups can simultaneously bind to cationic amino acid side chains that extend into the cleft between the two domains of each lobe of transferrin. From an inspection of the ferric transferrin crystal structure, the most likely anion binding residues in the cleft are Arg-632 and Lys-534 in the C-terminal lobe and Lys-206 and Lys-296 in the N-terminal lobe.

Homogeneous catalysts for selective molecular oxygen driven oxidative decarboxylations

Cobalt (II) ion has been found to catalyze the molecular oxygen driven oxidation of N-(phosphonomethyl)iminodiacetic acid (PMIDA) to N-(phosphonomethyl) glycine (PMG) in aqueous solution. This homogeneous catalytic conversion is novel and represents, in effect, an oxidative dealkylation of one carboxymethyl moiety yielding the N-substituted glycine. The reaction is selective to the desired product PMG when carried out at the natural pH of the free acid substrate (∼1-2) and when carried out at substrate loadings less than 5% by weight. In addition, the catalytic system is selective for the PMIDA substrate; i.e., other closely related ligands show no reactivity, e.g., NTA, EDTA, etc. The results of kinetic and mechanistic studies on dilute systems are presented and discussed with special emphasis on how an understanding of the mechanism can make it possible to generate a catalyst system that gives high yields even with high substrate loadings

Titration of phosphonic acid derivatives in mixtures

An analytical procedure is described for the determination of the weak acids phosphonomethyliminodiacetic acid and phosphonomethyliminoacetic acid in their mixtures, and the dissociation constants of phosphonomethyliminoacetic acid are reported.