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Facile Chemical Fabrication of Designer Biofunctionalized Nanomaterials
Published in Vineet Kumar, Praveen Guleria, Nandita Dasgupta, Shivendu Ranjan, Functionalized Nanomaterials I, 2020
In immunoassays for the detection of antigens, antibodies are conjugated on the nanoparticle surface. Immunoglobulin G is immobilized on the nanoparticle surface for the specific in vitro recognition of antigenic protein G present on the cell surface of staphylococcus bacteria. Similarly, protein tags are employed in purifying proteins, expressing an additional fusion protein or short amino acid sequence modified by a genetic engineering technique which acts like a tag. A well-known example is the polyhistidine tag where six or more histidine residues are tagged at any one terminus of protein. These his-tagged proteins bind specifically and strongly to nitrilotriacetic acid (NTA) or iminodiacetic acid (IDA) via a chelation complex with Ni2+ or other bivalent metal ions (Li et al., 2007). The resins (sepharose or agarose) functionalized with Ni-NTA or Ni-IDA are packed in the column and used for the purification of proteins containing the ‘his’ tag. Due to the strong affinity of he timidazole group of histidine with the NTA complex, this strategy is used for the purification of proteins.
Adsorption and Ion-Exchange Processes
Published in Thomas E. Carleson, Nathan A. Chipman, Chien M. Wai, Separation Techniques in Nuclear Waste Management, 2017
These types of ion-exchange resins are typically commercially produced. However, there have been a large number of resins produced in small quantities by various researchers. The synthesis and use of this type of resin has been reviewed, both by Millar and coworkers35 and by Eccles and Greenwood.36 The use of chelating resins for analytical chemistry purposes was reviewed by Myasoedova, Savvin, and Vernadsky in 1986.37 There are a number of desirable properties that form the basis for the synthesis of this type of resin. The major properties are high metal capacity, high selectivity, fast kinetics, and high mechanical strength. There are basically four groups of commercial resins available today, each containing one of the following groups: iminodiacetic acid, aminophosphonic acid, amidoxime, or thiol.36 Typical commercial resins with these functional groups are Amberlite IRC-718 or Chelex-100®, which contain iminodiacetic acid groups (Chelex is supplied by Bio-Rad Chemical Division), Duolite C-467 with aminophosphonic acid groups, Duolite C-346, which contains amidoxime groups, and Purolite® S-920 or Duolite GT-73 with thiol groups.35 (Duolite is a trademark of DISA Limited, U.K. and Purolite is carried by Rohm and Haas Co.; resins are from Purolite Co.) The cost of synthesizing these types of resins is substantially higher than that of ordinary ion-exchange resins. Perhaps it is this higher cost that limits the number of different commercial chelating resins currently available.
Polymers in Special Uses
Published in Manas Chanda, Plastics Technology Handbook, 2017
Some polystyrene resins (cross-linked with DVB) are specially modified to have chelating functional groups bound to the matrix so as to make them selective towards certain ions. Such resins with iminodiacetic acid groups are marketed under the trade names Dowex A-1 (Dow Chemical) and Chelex 100 (Bio-Rad Laboratories). The complex (XXVI) formation constants with metal ions of the chelating resin are so large that the resin absorbs metal ions equivalent to the iminodiacetic acid groups (used in sodium salt form), i.e., the efficiency of metal ion adsorption is near 100%. A particular metal ion can be removed by controlling the pH of aqueous solution. For example, at pH 2, mercury and copper ions are preferentially adsorbed, while zinc, cobalt, and cadmium ions are little adsorbed.
Review: Recent advances of one-dimensional coordination polymers as catalysts
Published in Journal of Coordination Chemistry, 2018
Edward Loukopoulos, George E. Kostakis
Despite the success and popularity of salen-based coordination compounds in this reaction, suitable compounds based on other ligands have also been proposed. A Mn(II) 1-D CP with the ligand N-(4-carboxybenzyl) iminodiacetic acid (H3cia) was reported in 2014 by Lymperopoulou [69] and co-workers, also showing catalytic activity in the epoxidation of alkenes. The compound, formulated as [Mn(Hcia)(H2O)] (7), forms 1-D ladder-like chains with the ligand being only partially deprotonated (Figure 6), as the benzoic group remains intact and participates in H-bonding interactions. Catalysis-wise, 7 promotes the epoxidation of a large range of olefins when hydrogen peroxide and ammonium acetate were added, respectively, as oxidant and additive (Scheme 4). Typically the reactions proceeded at room temperature and were completed in 6 h, providing epoxide products with moderate to high conversions (up to 81%) and excellent selectivities (up to 100%).
Selective Removal of Transient Metal Ions from Acid Mine Drainage and the Possibility of Metallic Copper Recovery with Electrolysis
Published in Solvent Extraction and Ion Exchange, 2023
Jelena Toropitsyna, Luděk Jelinek, Ross Wilson, Martin Paidar
Vecino et al.[31] studied two types of resins (Lewatit VP OC 1026, containing Bis-2-ethylhexylphosphoric acid (DEHPA) and Lewatit TP 207 – the cation ion exchange resin containing an iminodiacetic acid (IDA) group) for the sequential extraction of Cu(II) and Zn(II) from AMD (batch and column experiments). The best extraction of Zn(II) was obtained using resin with DEHPA – VP1026, being higher than 96% (pH = 2.6–2.8), whereas resin containing an iminodiacetic acid group – TP 207 was optimal for Cu(II) extraction (>99%) at pH = 3–4. In dynamic experiments, it was possible to separate and concentrate Zn(II) and Cu(II) using both resins.
Synthesis, characterization, and quantum chemical study of cobalt(II) chelates with N-phenethyl-iminodiacetate(2-)-like ligands. Influence of p-(R)-phenethyl group on crystal pattern
Published in Journal of Coordination Chemistry, 2022
Dheerendra Kumar Patel, Alicia Domínguez-Martín, Duane Choquesillo-Lazarte, Josefa María González-Pérez, Juan Niclós-Gutiérrez
The acid form of tridentate chelating ligand H2MOpheida was obtained as previously reported for N-phenethyl-iminodiacetic acid (H2pheida) [4], but using 4-methoxy-phenethylamine instead of N-phenethylamine. The amine was purchased from Aldrich and used without purification. Cobalt(II) basic carbonate [(CoCO3·Co(OH)2·2H2O), Merck, Co 47%] was used as received. In order to determine accurately the amount of Co(II) required as a source of metal for synthesis, elemental micro-analysis and thermo gravimetric analysis is encouraged.