Loading Capacity Of Resin Research Articles

SpyFixer enables efficient site-specific immobilization for protein-protein interaction analysis and antibody purification.

Traditional methods of protein immobilization often result in activity loss due to random coupling. This study introduces SpyFixer, a variant of SpyCatcher that achieves over 99 % efficient site-specific protein immobilization. We applied SpyFixer on two platforms: bio-layer interferometry (BLI) for protein-protein interaction analysis and epoxy agarose resin for antibody purification. Using human growth hormone (hGH) and the Z domain of Protein A as model proteins, we demonstrated that SpyFixer enables efficient, site-specific immobilization on BLI sensors, yielding reproducible kinetic data with lower variability than conventional methods. Additionally, we developed a cost-effective strategy for antibody purification utilizing SpyFixer-modified resin, which exhibited remarkable capture efficiencies exceeding 90 %, elution efficiencies over 70 %, and purities over 90 % for human immunoglobulin G (hIgG) from complex samples, including bacterial lysates, human serum, and recombinant fermentation broth. The resin's loading capacity surpassed 200 mg/mL, and no significant activity loss was observed after 20 regeneration cycles. This study further advances the potential of Spy chemistry in biotechnological applications.

Xanthone- and benzophenone-enriched nutraceutical: Development of a scalable fractionation process and effect of batch-to-batch variation of the raw material (Cyclopia genistoides)

Extracts of honeybush (Cyclopia genistoides) containing glucosylated xanthones and benzophenones inhibit α-glucosidases, a group of key glycolytic enzymes and drug targets in the treatment of type 2 diabetes mellitus. Ultrafiltered C. genistoides extract was used as the starting material for the development of an optimized protocol to produce xanthone- and benzophenone-enriched fractions (XEFs and BEFs, respectively) by macroporous adsorbent resin chromatography. Static sorption experiments were performed to determine resin loading capacity. Adsorption isotherm data were fitted to the Langmuir and Freundlich models. A fractionation protocol using step-wise gradient elution with 0–30% EtOH-water mixtures was developed, based on the results of dynamic sorption experiments. All XEFs contained 3-β-D-glucopyranosyliriflophenone due to co-elution with the xanthones, mangiferin and isomangiferin, whereas BEFs contained zero or trace amounts of xanthones. Phenolic variation between different batches of the raw material (n = 10) manifested as variation in the composition and degree of enrichment of BEFs and XEFs. This scalable, eco-friendly enrichment strategy should find application for the preparation of enriched fractions from other herbal plants containing the target compound.

Treatment of monazite processed effluent to recover rare earth metals (REMs)

Improper disposal of effluent generated in rare earth mining areas and ore processing industries results in loss of REMs and miserably affects the ecosystem. Thus, their appropriate treatment is required, which can be achieved via environmentally feasible processes. In this connection, systematic scientific adsorption studies were carried out to separate REMs using cationic resin, Amberlite IR120 Na from the effluent generated during monazite processing for REMs recovery. To optimize feasible conditions for REMs recovery, bench scale studies were carried out varying different process parameters viz. pH, contact time, resin dose, etc. It was observed that adsorption of 92.63% La, 92.79% Ce, 91.45% Nd, 90.95% Pr and 95.09% Sm was achieved at aqueous/ resin (A/R) ratio 25 mL/g, pH 1.3 and contact time 10 min. Loading capacity of resin was found to hold 48.57 mg REMs/g resin. The adsorption data followed the second order reaction ((t/q) = (1/h) + (1/qe)(t)) and Langmuir adsorption isotherm (1/q = [(1/k1 qm)(1/Ce)] + (1/qm)). The loaded REMs was effectively eluted using 15% H2SO4 in 10 min. The REMs enriched solution was treated to get pure REM oxides as precipitate. This technical application will be useful for REMs recovery as well as to mitigate environmental pollution.

Recovery of nickel and molybdate from ammoniacal leach liquors of spent HDS catalysts using chelating ion exchange resin

Spent hydrodesulphurization (HDS) catalysts containing valuable Mo and Ni ions are potential source for the recovery of Mo and Ni from the point of commercial, environmental and conservation of natural mineral resources. In the present study, oxidative roasting of spent HDS catalyst followed by ammonia leaching results in the leach liquor with about 15.3 g/L Mo (~85% recovery), ~125 g/L (NH4)2SO4 and ~0.9 g/L Ni as impurity. Therefore Ni separation from this ammoniacal molybdate leach liquor is essentially the first step to obtain high pure molybdate and ammonium sulfate solution. In this study, separation of nickel from ammoniacal molybdate leach liquor was reported using commercial chelating iminodiacetate resin, Lewatit TP207 by batch and column methods. Optimization of process parameters include equilibration time, acidity of leach liquor, aqueous flow rate, metal concentration, loading capacity of resin for Ni during sorption of Ni, desorption of nickel from loaded resin and stability and reuse of resin in continuous column experiments. Feed leach liquor of pH >8.0 is important to achieve clear separation of Ni from Mo. Loading capacity of resin and break through curves are optimized to achieve <10 mg/L Ni in purified Mo leach liquor and further processing results in high grade ammonium octamolybdate (AOM) and ammonium sulfate crystals. Finally, a process flow sheet for the complete separation and recovery of Ni, Mo and ammonium sulphate with material balance from ammoniacal molybdate leach liquor of spent HDS catalyst was demonstrated for possible industrial application.

Preparation of Silica-4-(2-pyridylazo) Resorcinol Chelator for Solid Phase Extraction of Transition Metals from Groundwater

The determination of trace heavy metals in environmental samples requires reliable sample preparation method to improve instrument detectability or minimize matrices effect. Solid phase extraction (SPE) using metal chelators is an attractive approach for the selective extraction of trace metals from aqueous media in various applications. In this work, chelating resin was prepared by chemical attachment of the chelating moiety, 4-(2-pyridylazo)resorcinol(PAR) onto silica gel using an eco-friendly chemical transformation. The successfulness of the chemical modification was confirmed by Fourier transform infrared (FTIR), elemental analysis (EA) and scanning electron microscopy (SEM). The separation/preconcentration conditions of analytes including exchange capacity, effect of pH, adsorption kinetics and isotherm for metal extraction, were investigated.At optimum conditions, the resin loading capacity for the metals Cu2+, Ni2+ and Mn2+were 0.121, 0.132 and 0.124 mmolg-1in that order. The material performance as SPE sorbent for trace metals has been assessed usingCu2+, Ni2+ and Mn2+ in certified reference natural water sample, and real groundwater samples from Almedinah AlMunawarah. The accurate and precise results verify the resin appropriateness for matrix removal/ preconcentration prior to the analysis of heavy metals from this type of matrices.

Novel imino diacetamide styrene divinyl benzene resin for separation of99molybdenum from irradiated uranium–aluminium alloy

Imino diacetamide styrene divinyl benzene (IDAA SDVB) resin was synthesized and evaluated for separation of molybdenum (Mo) from simulated dissolver solution of irradiated uranium–aluminium alloy. Detailed studies were carried out to understand the influence of various parameters on sorption of Mo. The kinetics of Mo sorption is found to be fast and the kinetics data fit well to the pseudo-second order kinetic equation. Sorption of Mo is found to decrease with the increase of feed acidity. The loading capacity of resin is determined to be 30 mg g−1, the sorption isotherm data fit well to the Langmuir model. Batch sorption experiments with simulated dissolver solution showed quantitative uptake of Mo along with some co-extraction of iodine (I). Column runs have demonstrated that co-extracted ‘I’ could be scrubbed easily with solutions of feed acidity. Finally, sorbed Mo could be eluted with 3.0 M HNO3. XAFS and FT-IR studies of Mo sorbed on to IDAA SDVB resin have shown that Mo is sorbed in the +6 oxidation state (in the form of MoO42−), wherein the complex attains octahedral geometry with contribution from four oxygen atoms of the molybdate anion and two oxygen atoms of the amidic moiety of the imino-diacetamide ligand.

Poly(styrene-co-divinylbenzene)-PAMAM-IDA chelating resin: Synthesis, characterization and application for Ni(II) removal in aqueous

PS-PAMAM-IDA chelating resins were prepared by low-generations of polyamidoamine (PAMAM) and then chloroacetic acid functionalizing commercially available ammoniated polystyrene matrix, to preconcentrate Ni2+ from synthetic aqueous samples. Different generations of PAMAM were used to obtain different chelating resins, PS-IDA, PS-1.0G PAMAM-IDA and PS-2.0G PAMAM-IDA. The synthesized resins were characterized by FTIR and elemental analysis. The effect of solution pH, kinetic studies, resin loading capacity, matrix effects etc., on metal ion adsorption to adsorbent phase, were studied by batch method. The PS-1.0G PAMAM-IDA resin was the most excellent adsorbents, with a maximum adsorption capacity of (24.09±1.79) mg/g for Ni2+ ion at pH=7. The interpretation of the equilibrium data was given by Langmuir isotherms model, and the correlation coefficient values for PS-IDA, PS-1.0G PAMAM-IDA and PS-2.0G PAMAM-IDA resins were 0.992, 0.994 and 0.987, respectively.

Adsorption of gold(III) from waste rinse water of semiconductor manufacturing industries using Amberlite XAD-7HP resin

Advanced hydrometallurgical separation processes are gaining significant importance for the recovery of gold from the aqueous solutions viz. leach liquor of waste electronics, plating material solutions, and waste wash water from electronic industries. In the present investigation, gold adsorption from the waste rinse water of semiconductor manufacturing industries is reported using Amberlite XAD-7HP. For experimental purposes, chloride waste rinse water that contained primarily Au (281 mg/ L) with trace amounts of Cu, Ni, Zn, Sn etc was used. Batch studies were carried out to optimize various process parameters, including contact time, acidity of solution, and resin dosage for the adsorption of gold from the above waste effluent. Adsorption of 92.25% gold was found from the waste solution within a contact time of 30 minutes at an aqueous to resin (A/R) ratio of 25 mL/g and an equilibrium pH of 0.63. In optimal conditions, the loading capacity of resin for gold was observed to be 58.82 mg of gold/g of resin. The gold adsorption phenomena were confirmed by the comparative FT-IR spectroscopic characterization studies of fresh resin and gold loaded resin. Elution tests were carried out for the elution of gold from the gold loaded resin using various ratio mixtures of acetone and 1.0 M HCl. An elution efficiency of 96.96% gold was achieved at an acetone-to-acid ratio of 9. In this condition, gold-enriched solution containing 7,240 mg gold/ L was obtained. The maximum elution of gold was found to be 99.33% using pure acetone in a contact time of 30 minutes. The data obtained will be useful to simulate the continuous gold adsorption process within a column.

Steric hindrance effect on adsorption of metal–organic complexes onto aminophosphonate chelating resin

Recovery of nickel and cobalt from organic acid complexes generated by bioleaching of nickel laterite ores with heterotrophic organism and their metabolites were conducted by ion-exchange. This study investigated specifically the adsorption of nickel and cobalt complexed with citrate, malate and lactate on chelating aminophosphonate Purolite S950 and the possible steric hindrance imposed by the larger bulky metal species on the resin loading capacity. Equilibrium adsorption tests of various concentrations of metal complexes were measured and analysed by fitting the experimental adsorption data to two empirical isotherm models: Langmuir and Freundlich. The distribution of nickel and cobalt speciation estimated from the stability and formation quotient constants of these metal complexes were used in examining the roles of steric hindrance in the adsorption of metal complexes on S950. Analysis of the mechanism of adsorption of these complexes suggests the size and the nature of the metal species have a significant influence on the metal uptake. In general the metal loading capacity of the resin increased as the size of the metal complexes decreased. The type and the number of anions which coordinated with the metal as ligands dictated the size of the complexes. An interesting outcome of this study, however, is the generally higher uptake of the weakly acidic lactate complex in comparison to the smaller hydrous nickel ion; thus suggesting the important roles of both physical and chemical properties of the metal species in their adsorption on resins. In general the order of the uptake of metal species on S950 is: lactate > metal ion > malate > citrate.

Treatment of wastewater containing Pb and Fe using ion‐exchange techniques

AbstractTreatment of wastewater containing lead and iron was examined using two different ion‐exchange resins namely Duolite ES 467 (containing amino‐phosphonic functional groups) and a chelating ion‐exchange resin (containing hydroxamic acid functional groups). Initially different sorption parameters such as contact time, pH, concentrations of sorbent, sorbate and chloride ion were studied. The sorption kinetics was observed to be fast and equilibrium could be reached within 30 min. Lead sorption efficiency increased with increase in pH whereas the opposite trend was observed with iron. The presence of chloride ions greatly reduced the Pb sorption efficiency in the case of Duolite ES 467. Column studies were carried out to recover Pb and Fe individually using Duolite ES 467 resin. The maximum uptake of Pb at pH 2 and 3 was observed to be 11.63 and 33.96 g dm−3 of resin respectively. Similarly, for Fe at pH 2 and 3 the uptake was observed to be 10.07 and 6.96 g dm−3 of resin respectively. In the presence of chloride ions, column studies were carried out using Duolite ES 467 for iron and chelating ion‐exchange resin containing hydroxamic acid functional groups for lead sorption. Hydroxamic acid resin's loading capacity remains constant for at least up to 20 cycles. Copyright © 2005 Society of Chemical Industry

A column system for the selective extraction of U(VI) and Th(IV) using a new chelating sorbent

A new method has been developed using (bis-3,4-dihydroxy benzyl) p-phenylene diamine functionalized to XAD-16 (a polystyrene divinyl benzene copolymer) matrix, to preconcentrate mainly U(VI) and Th(IV) from synthetic and real samples. The developed method is free from matrix interference due to alkali and alkaline metal ions and preconcentrates the actinides with a high degree of selectivity, with consistent trace recoveries. The new chelating resin provides dramatic improvement in metal exchange rate, with half value saturation time ( t 1/2) of less than 1.6 min. The developed method was superior in its metal loading capacity for U(VI) and Th(IV), with values of 0.666 and 0.664 mmol g −1, respectively. Various physio-chemical properties like effect of solution pH, kinetic studies, resin loading capacity, sample breakthrough volume, matrix effects etc., on metal ion sorption to sorbent phase, were studied using both batch and column method. The new chelatogen was applied to extract U(VI) from near neutral real water samples. Preconcentration and separation of metal ions were possible through pH variation and also by varying the eluant concentration. A high preconcentration factor value of 350 with a lower limit of detection of 20 and 30 ng cm −3 was obtained for U(VI) and Th(IV), respectively. The practical applicability of the developed resin was examined using synthetic and real samples such as sea/well water samples. The method provides low relative standard deviation values of <3.5% for all analytical measurements, reflecting on the reproducibility and accuracy of the developed method. The new resin is quite durable with recycling time >35 cycles, without any major change in its quantitative metal uptake nature.

Studies on a Dithiane-Protected Benzoin Photolabile Safety Catch Linker for Solid-Phase Synthesis.

Substituted benzoinyl systems 8a-g, differing either in the substitution pattern, type of resin matrix used, or resin loading capacity, were prepared and the kinetics of their photolytic cleavage of Fmoc-beta-alanine examined on resin. The linker systems 6a-g were assembled in near-quantitative yield using Corey-Seebach dithiane addition. The dithiane group that serves as a safety catch against premature photoreaction was removed by either oxidation or alkylation. Analytical methods that include FTIR and (13)C gel-phase NMR spectroscopy were used for rapid reaction monitoring and sample characterization on resin. A survey of different substituted systems 8c-f for releasing Fmoc-beta-alanine confirmed that the 3-alkoxybenzoin linker photocleaves most rapidly to give the highest yield (tau(1/2) = 6.7 min; 98% yield). Lowering the resin loading from 0.59 mmol/g in 8a to 0.26 mmol/g in 8b improved the cleavage kinetics to tau(1/2) = 2.6 min, 92% yield. Tentagel resin 8g exhibits similar photocleavage kinetics in both organic and aqueous media and when compared to the polystyrene counterpart, 8a. The 3-alkoxybenzoin linker 6a was also loaded with aryl carboxylic acids (12h,i) and hindered Fmoc-protected amino acids (12j-l) with varying degrees of success (57-100%) and dithiane deprotected (70-80%, 13h-l) followed by photocleavage with comparable efficiencies (89-93% after 60 min).