Ion-exchange resins improve the analysis of metal nanoparticles in wastewater using single-particle inductively coupled plasma-mass spectrometry.

Improved measurement and analysis technologies are needed for investigating nanoparticle generation characteristics in sewage treatment plants. Single-particle inductively coupled plasma-mass spectrometry (spICP-MS) can be used to analyze metal nanoparticle characteristics. However, during spICP-MS analysis of environmental samples, high concentrations of ionic materials obscure the signals of particulate materials by increasing background signals. This can increase the threshold value for separating background and particle signals and increase the background-equivalent diameter (BED). In this study, particle size distributions in influent and effluent collected from sewage treatment plants were investigated using an improved spICP-MS method combining spICP-MS with ion-exchange resin (IER) column pretreatment. The ion removal effect of the IER column was first examined using a synthetic mixture of Ag nanoparticles (AgNPs) and ions. The method was then applied to wastewater from six different sewage treatment plants using an optimal IER packing of 5 g. The ion removal efficiency for samples containing a proper mixture of AgNPs and Ag ions was 99.98%, and the BED significantly decreased from 73.0 ± 1.0 to 6.1 ± 0.3 nm. Particle size distributions measured in the treatment plant influent and effluent ranged from 28.5 nm (Co) to 220.3 nm (Mg) and from 26.8 nm (Co) to 291.8 nm (Mg), respectively. spICP-MS/IER enabled the detection of smaller particles by removing ions from the sample and significantly decreasing the size detection limit. The results of this study offer a reference for developing predictive models for removing metal nanoparticles during sewage/wastewater treatment.

Impact of seasonality and forest stand age on ion deposition in rehabilitated forests.

This study examines the critical interaction between seasonal precipitation variability and forest maturity in determining ion deposition patterns in rehabilitated forest ecosystems. This research was conducted in rehabilitated forest sites in Bintulu, Sarawak, Malaysia that had ecologically similar plant distribution, species, and age in each planting area. This facilitated the standardization of rainfall deposition in the different study plots which streamlined the study of these specific facets of ecosystem dynamics. The goal is to understand how seasonal changes and the age of the forest influence the chemical composition of the flux that relates to the movement and deposition of nutrients through the forest ecosystem. This flux is a key factor in the health of the forest ecosystem and nutrient cycling. Using ion exchange resin (IER) samplers, we accurately measured and compared the deposition of different ions (Ca2+, Na+, Fe2+, Cu2+, NO3 -, NH4 + and SO4 2-) across different seasons and forest ages. The deposition of Ca2+ and NH4+ was significantly lower in the low-precipitation season than in the high-precipitation season in all forest stands, regardless of the year they were established (1996, 1999, 2002, 2005, and 2009). In contrast, ions such as Na+, Fe2+, Cu2+, NO3 - and SO4 2- showed no clear seasonal fluctuations. In addition, the study shows that through-fall in forest stands from 2002, 2005 and 2009 had higher concentrations of Ca2+ in both seasons than in 1996 and 1999. Interestingly, forest stands from 2009 and 2002 had elevated levels of Na+ and SO42- in seasons with low precipitation, while stands from 1996 had higher levels in seasons with high precipitation. Our results emphasize the crucial role of precipitation amount and canopy age in determining ion deposition in forest ecosystems. By demonstrating the significant influence of precipitation seasonality and forest maturity on the chemical composition of throughfall, this study contributes to a deeper understanding of nutrient dynamics in developing forest landscapes and provides valuable insights for ecological restoration measures.

Separation and purification of nylon 54 salts from fermentation broth by an integrated process involving microfiltration, ultrafiltration, and ion exchange.

Nylon 54 is a novel, biodegradable polyamide with excellent thermal resistance and water absorption properties. It can be polymerized using bio-based cadaverine and succinic acid as monomers. Traditional separation methods isolate individual monomers from the fermentation broth through acidification or alkalization, resulting in significant amounts of waste salts; however, synchronous separation of dibasic acids and diamines has not been reported. This study investigated an integrated process for the separation and extraction of nylon 54 salts from a co-fermentation broth without acidification or alkalization. We meticulously optimized the operational parameters of the integrated process to achieve maximum separation efficiency. Following microfiltration, ultrafiltration, and decolorization, the bacterial eliminating rate was ≥99.83%, and the protein concentration was ≤40 mg/L. The absorbance of the decolorized solution was ≤0.021 at 430 nm, and the recovery rate of nylon 54 salt reached 97%. Then, the pretreated solution was passed through sequential chromatographic columns, which effectively removed organic acid by-products (such as acetic acid and lactic acid), SO4 2-, and NH4 + from the fermentation broth, resulting in a cadaverine yield of 98.01% and a succinic acid yield of 89.35%. Finally, by concentrating and crystallizing the eluent, the simulated fermentation broth yielded nylon 54 salt with a purity of 99.16% and a recovery rate of 58%, and the real fermentation broth yielded nylon 54 salt with a purity of 98.10% and a recovery rate of 56.21%. This integrated process offers a sustainable and environmentally friendly pathway for the complete biosynthesis of nylon 54 salt and has the potential to be extended to the preparation of other nylon salts.

Application of ion-exchange dynamic conditions in the recovery of precious metals from refining waste.

The objective of this study was to assess the potential for recovering precious metals from technological solutions using an ion-exchange dynamic method. Precious metals like platinum, palladium, rhodium, and gold are essential materials in various industries such as: automotive, electronics, pharmaceuticals, and jewellery. Due to their limited occurrence in primary sources, there is a growing trend in the market to extract these metals from secondary sources. The research involved conducting sorption and elution tests under different parameters to investigate their impact on the process in dynamic conditions. Additionally, an attempt was made to calculate the operational and total capacity of the resins, which has not been done previously for industrial solutions. The results showed that using Puromet MTS9200, Puromet MTS9850, and Lewatit MonoPlus MP600 resins, the sorption process could be effectively carried out in dynamic conditions with a contact time of 5 min between the technological solution and the resin bed. For optimal elution, the contact time between the eluent solution and the bed should range between 10 and 30 min. To improve rhodium sorption efficiency, it was found that neutralizing the technological solution to a pH of approximately 7 and using Lewatit MonoPlus MP600 resin could be beneficial.

Analytical strategies for sensitive and precise determination of 87Sr/86Sr in olive oil through ion extraction, chromatographic separation, and multicollector inductively-coupled plasma mass-spectrometry.

Several food regulatory bodies regard olive oil as highly susceptible to food fraud, largely due to its substantial economic worth. Precise analytical tools are being developed to uncover these types of fraud. This study examines an innovative approach to extract strontium (Sr) from the olive oil matrix (via EDTA complexation and ion-exchange chromatography) and to determine its isotope composition by MC-ICP-MS. This technique was compared to a commonly used technique (i.e. acid extraction and extraction chromatography), and then validated. Three olive oils that are sold in France were prepared and analyzed by two methods: 1) acid extraction prior to Sr purification by Sr-spec resin and 2) complexation by EDTA prior to Sr purification by AG50W-X8. These methods were applied for the determination of the 87Sr/86Sr isotope ratio of 23 olive oils from various countries. We also demonstrated the feasibility of the method for the detection of olive oil mixtures.

Solid-State NMR Characterization of Mefloquine Resinate Complexes Designed for Taste-Masking Pediatric Formulations.

Mefloquine (MQ) is an antimalarial medication prescribed to treat or malaria prevention.. When taken by children, vomiting usually occurs, and new doses of medication frequently need to be taken. So, developing pediatric medicines using taste-masked antimalarial drug complexes is mandatory for the success of mefloquine administration. The hypothesis that binding mefloquine to an ion-exchange resin (R) could circumvent the drug's bitter taste problem was proposed, and solid-state 13C cross-polarization magic angle spinning (CPMAS) NMR was able to follow MQ-R mixtures through chemical shift and relaxation measurements. The nature of MQ-R complex formation could then be determined. Impedimetric electronic tongue equipment also verified the resinate taste-masking efficiency in vitro. Variations in chemical shifts and structure dynamics measured by proton relaxation properties (e.g., T1ρH) were used as probes to follow the extension of mixing and specific interactions that would be present in MQ-R. A significant decrease in T1ρH values was observed for MQ carbons in MQ-R complexes, compared to the ones in MQ (from 100-200 ms in MQ to 20-50 ms in an MQ-R complex). The results evidenced that the cationic resin interacts strongly with mefloquine molecules in the formulation of a 1:1 ratio complex. Thus, 13C CPMAS NMR allowed the confirmation of the presence of a binding between mefloquine and polacrilin in the MQ-R formulation studied.

Efficiency enhancement of electrocoagulation, ion-exchange resin and reverse osmosis (RO) membrane filtration by prior organic precipitation for treatment of anaerobically-treated palm oil mill effluent.

Anaerobically-treated palm oil mill effluent (POME) still has unacceptable properties for water recycling and reuse, with an unpleasant appearance due to the brownish color caused by tannins and phenolic compounds. This study proposes an approach for treating anaerobically-treated POME for water recycling by combining organic precipitation, electrocoagulation (EC), and ion-exchange resin, followed by reverse osmosis (RO) membrane filtration in series. The results indicated that the organic precipitation enhanced the efficiency of EC treatment in reducing the concentrations of tannins, color, and chemical oxygen demand (COD) of the anaerobically-treated POME effluent, with reductions of 95.73%, 96.31%, and 93.96% for tannin, color, and COD, respectively. Moreover, organic precipitation affected the effectiveness of Ca2+ and Mg2+ ion removal using ion exchange resin and RO membrane filtration. Without prior organic precipitation, the ion-exchange resin process required a longer contact time, and the RO membrane filtration treatment was hardly effective in removing total dissolved solids (TDS). The combined process gave a water quality that meets the criteria set by the Thailand Ministry of Industry for industrial boiler use (COD 88 mg/L, TDS <0.001 mg/L, water hardness <5 mg-CaCO3/L, and pH 6.9).

Perfluoroalkyl acid adsorption by styrenic ß-cyclodextrin polymers, anion-exchange resins, and activated carbon is inhibited by matrix constituents in different ways.

Perfluoroalkyl acids (PFAAs) are ubiquitous environmental contaminants of global concern, and adsorption processes are the most widely used technologies to remove PFAAs from water. However, there remains little data on the ways that specific water matrix constituents inhibit the adsorption of PFAAs on different adsorbents. In this study, we evaluated the adsorption of 13 PFAAs on two styrene-functionalized ß-cyclodextrin (StyDex) polymers, an activated carbon (AC), and an anion-exchange resin (AER) in the absence and presence of specific water matrix constituents (16 unique water matrices) in batch experiments. All four adsorbents exhibited some extent of adsorption inhibition in the presence of inorganic ions and/or humic acid (HA) added as a surrogate for natural organic matter. Two PFAAs (C5-C6 perfluorocarboxylic acids (PFCAs)) were found to exhibit relatively weak adsorption and five PFAAs (C6-C8 perfluorosulfonic acids (PFSAs) and C9-C10 PFCAs) were found to exhibit relatively strong adsorption on all four adsorbents across all matrices. Adsorption inhibition was the greatest in the presence of Ca2+ (direct site competition) and HA (direct site competition and pore blockage) for AC, NO3- (direct site competition) and Ca2+ (chemical complexation) for the AER, and SO42- (compression of the double layer) for the StyDex polymers. The pattern of adsorption inhibition of both StyDex polymers were similar to each other but different from AC and AER, which demonstrates the distinctive PFAA adsorption mechanism on StyDex polymers. The unique performance of each type of adsorbent confirms unique adsorption mechanisms that result in unique patterns of adsorption inhibition in the presence of matrix constituents. These insights could be used to develop models to predict the performance of these adsorbents in real water matrices and afford rational selection of adsorbents based on water chemistry for specific applications.

Incorporation of spent ion exchange resin simulate into cement composites.

Solidification/Stabilization (S/S) of spent radioactive ion exchange resins (IER) is one of many critical problems facing developing nuclear industries all over the world. Immobilization technology using Ordinary Portland Cement (OPC) as an inert matrix, has been widely applied for the solidification/stabilization of spent ion exchange resin. In this study incorporation of simulated IER into cement matrix and characterization of the final solid waste form (FWF) had been searched practically in laboratory scale experiments. Factors that can affect the properties of the FWF including the water/cement (w/c) ratios and the resin concentration were studied systematically. Mechanical integrities, thermal analysis, and mass loss during hardening and curing for 28 days were evaluated for FWF hard blocks. Scanning Electron Microscope (SEM) and X-Ray Diffraction (X-RD) examinations were performed to investigate the internal architecture of the FWF. Moreover, the heat of cement hydration reactions was recorded during the IER solidification process. Based on the experimental results obtained, it is worth to state that according to its acceptable characteristics and advantages of cement as an inert matrix, it can be suggested safely for the immobilization of untreated spent radioactive ion exchange resins.

Construction and in vitro/in vivo evaluation of menantine hydrochloride oral liquid sustained-release drug delivery system.

OBJECTIVE: The purpose of the present study was to formulate a menantine hydrochloride (MH) sustained-release suspension. METHODS: Menantine hydrochloride drug resin complex (MH-DRC) was prepared with strong acid cation exchange resin as carrier using water bath method. The MH-DRC was characterized using scanning electron microscopy, X-ray diffraction and infrared spectroscopy. The MH-coated microcapsule (MH-CM) with optimized formulation was further dispersed in a suitable medium to obtain a sustained-release suspension. The rats were given both the MH sustained-release suspension and the commercial MH sustained-release capsule by intragastric administration. The plasma concentration-time curves and related pharmacokinetic parameters were also investigated using a non-atrioventricular model. RESULTS: MH and ion-exchange resin were ionically bonded. AmberliteIRP®69 had a higher affinity for MH at the initial concentration of 5 mg·mL-1 and a reaction temperature of 25.0 ± 0.5 °C. In vitro drug release profile showed that both the drug resin complex and the coated microcapsules had a certain level of sustained-release effect. The t1/2 of MH sustained-release suspension was extended from 68.44 h to 72.79 h with the peak blood concentration being decreased to 3.56 µg·mL-1 and the Tmax extended to 12 h compared with the commercial MH sustained-release capsule. The concentration-time curve of the self-made MH sustained-release suspension was flattened and the average relative bioavailability (Fr) was 116.65% compared with the commercial MH sustained-release capsules. CONCLUSIONS: The findings showed that the MH sustained-release suspension was successfully formulated with acceptable pharmacokinetic indices for effective treatment of Alzheimer's disease.

Assessing Abuse-Deterrent formulations utilizing Ion-Exchange resin complexation processed via Twin-Screw granulation for improved safety and effectiveness.

Opioid misuse is a public health crisis in the United States. In response, the FDA has approved drug products with abuse-deterrent features to reduce the risk of prescription opioid abuse. Abuse-deterrent formulations (ADFs) typically employ physical or chemical barriers or incorporate agonist-antagonist combinations as mechanisms to deter misuse. This study aims to assess the impact of abuse-deterrent properties, specifically ion-exchange resin complexation as a chemical barrier, on a model drug, promethazine hydrochloride (PMZ) tablets. Various formulations were developed through twin-screw wet granulation (TSWG) followed by twin-screw melt granulation (TSMG). In the TSWG process, the drug interacts with the resin through an exchange reaction, forming a drug-resin complex. Additionally, the study explored factors influencing the complex formation between the drug and resin, using the drug loading status as an indicator. DSC and ATR studies were carried out to confirm the formation of the drug-resin complex. Subsequently, hot melt granulation was employed to create a matrix tablet incorporating Kollidon® SR and Kollicoat® MAE 100P, thereby enabling sustained release properties. The drug-resin complex embedded in the matrix effectively deters abuse through methods like smoking, snorting, or parenteral injection, unless the drug can be extracted. In order to assess this, solvent extraction studies were conducted using an FDA-recommended solvents, determining the potential for abuse. Further investigations involved dissolution tests in change-over media, confirming the extended-release properties of the formulation. Results from dissolution studies comparing the ground and intact tablets provided positive evidence of the formulation's effectiveness in deterring abuse. Finally, alcohol-induced dose-dumping studies were conducted in compliance with FDA guidelines, concluding that the formulation successfully mitigates dose dumping in the presence of alcohol.

Preparation of azithromycin-ion exchange resin complexes for taste-masking and controlled drug release / 中国药科大学学报

@#In order to mask the bitterness of azithromycin (AZI) and individually regulate the drug release rate to reduce gastrointestinal irritation, immediate-release AZI-AmberliteTM IRP64/HPC and delayed-release AZI-AmberliteTM IRP69/RS100 were prepared by modifying with hydroxypropyl cellulose (HPC) and Eudragit RS100, respectively, and further combined to achieve controlled release.The drug loading and drug utilization rate of AZI-ion exchange resin complexes were measured; the structure of AZI-ion exchange resin complexes was characterized by differential scanning calorimetry and X-ray diffraction; and the wetting humidity, odor masking effects, in vitro dissolution and release behaviors were determined.The results showed that the formation of AZI-ion exchange resin complexes changed the original crystallization state of the drug, that the 2.5% HPC-modified AZI-AmberliteTM IRP64/HPC and the 0.5% RS100-modified AZI-AmberliteTM IRP69/RS100 demonstrated good taste masking effect, and that their combination in the drug content ratio of 13∶67 achieved the expected drug release behavior, i.e.rapid release of AZI in the first 10 min and smooth release in the later 6 h.These results indicated that the AZI-ion exchange resin complexes prepared by surface modification and their composites could mask the bitterness of AZI and realize the flexible adjustment of drug release rate, which lays the foundation for the research and development of new AZI preparations.

Lactic acid separation and recovery from fermentation broth by ion-exchange resin: A review.

Lactic acid has become one of the most important chemical substances used in various sectors. Its global market demand has significantly increased in recent years, with a CAGR of 18.7% from 2019 to 2025. Fermentation has been considered the preferred method for producing high-purity lactic acid in the industry over chemical synthesis. However, the recovery and separation of lactic acid from microbial fermentation media are relatively complicated and expensive, especially in the process relating to second-generation (2G) lactic acid recovery. This article reviews the development and progress related to lactic acid separation and recovery from fermentation broth. Various aspects are discussed thoroughly, such as the mechanism of lactic acid production through fermentation, the crucial factors that influence the fermentation process, and the separation and recovery process of conventional and advanced lactic acid separation methods. This review's highlight is the recovery of lactic acid by adsorption technique using ion-exchange resins with a brief focus on the potential of in-site separation strategies alongside the important factors that influenced the lactic acid recovery process by ion exchange. Apart from that, other lactic acid separation techniques, such as chemical neutralization, liquid-liquid extraction, membrane separation, and distillation, are also thoroughly reviewed.

Analysis of technical difficulties and new strategies of oral liquid pharmaceutical preparation for children / 药学学报

With the implementation of the two-child policy and the growing demand for child health, pediatric medication has been arousing widespread social concern. To develop the drugs suitable for children, including new compounds, new specifications and new dosage forms, is urgently required for pharmaceutical researchers. In this review, several technical bottlenecks for pediatric oral liquid preparations, as well as the novel strategies involved in drug nanocrystals, self-microemulsion, ion exchange resin and Pickering emulsion were discussed, which may be benefit to play a theoretical guiding role in the research and development of children's oral liquid formulation.

Preparation, characterization and in vitro release of berberine hydrochloride resin complex / 药学学报

The object of this study is to preparate the berberine hydrochloride (BBH) resin compound with taste masking effect. We took the BBH as the model drug and Amberlite IRP69 as the drug carriers, uncovered the curve of solubility of BBH in different cosolvent with a certain range of temperature, and then used it to calculate the parameters during the preparation of the complex such as adding quantity of BBH and the reaction temperature. Afterwards, the characteristic and in vitro release experiments were studied to verify the formation and predict the in vivo release behavior of the complex. The results showed that in the condition of using 60% ethanol as a cosolvent and stirring at 50 ℃ for 1 h, the drug loading and drug availability of the complex are at about 35% and 64%, respectively, and has a better taste-masking effect. In this study, a method was provided for preparing a taste-masking preparation of BBH.

Study on Separation and Purification Technology of Sanguinarine from the Extract of Macleaya cordata by Ion Exchange Resin / 中国药房

OBJECTIVE： To establish the separation and purification technology of sanguinarine from the extract of Macleaya cordata with ion exchang resin. METHODS： The content of sanguinarine from the extract of M. cordata was determined by HPLC， with  Cosmosil C18-R-Ⅱ column （250 mm×4.6 mm，5 μm）， mobile phase of acetonitrile-0.2％ acetic acid solution （25 ∶ 75，V/V）， the flow rate of 1 mL/min， detection wavelength of 270 nm， column temperature of 30 ℃， and sample size of 20 μL. Static adsorption and desorption tests were carried out to compare the adsorption and desorption properties of 8 ion exchange resins for sanguinarine. The optimum concentration of sample solution， pH value and volume of sample were investigated by optimum ion exchange resin. APPS 10D liquid phase preparation system was used to investigate the dynamic elution conditions and obtain M. cordata refined extract solution. The refined purified product of M. cordata was obtained by desalination， elution on a reversed-phase （RP） C18 column and drying.  The purity of the purified product was analyzed by HPLC. The structure of the purified product was confirmed by HPLC， UV spectrophotometry， MS and NMR. RESULTS： CM-FF resin was screened for the separation and purification of sanguinarine from M. cordata extract. It was eluted with 20 mmol/L ammonium acetate solution 100 mL containing 20％ methanol and 0.25 mol/L sodium chloride. The optimal dynamic absorption condition included that the concentration of sample was 6.0 mg/mL at pH 5.0，and the loading amount was 25 mL； after desalination and refinement， for the eluted refined extract， the purified product with 97％ purity （purified yield  of 71％） was obtained， and its structure was confirmed to be sanguinarine. CONCLUSIONS： The optimal separation and purification technology by ion exchange resin is green， safe， efficient and easy to operate， which can be used for the separation and purification of sanguinarine from M. cordata extract and is suitable for industrial production.

Purification of macroporous adsorption resin and decolorization of ion exchange resin of total saponins of Panax japonicus / 中草药

Objective: To establish a simple and effective extraction method for the preparation of total saponins of Panax japonicas (TSPJ). Methods: Combination of macroporous adsorption and ion exchange resin chromatography was adopted in the present study. For quality evaluation, chikusetsusaponin IVa was used as reference, and vanillin-perchloric acid was applied as chromogenic reagent to determine total saponin content at 545 nm. Results: X-5 macrophous resin offered better adsorption and desorption capacities for TSPJ than other macrophous resins. The optimum purification process was confirmed as follows: The sample solution concentration was 0.2 mg/L; The sample volume was 10 g/g, and eluting with 5 mL of 70% aqueous ethanol solutions on 1 g wet macrophous resin column. Followed this step, decoloring of TSPJ was studied and the decoloring capacity of two different types of ion exchange resins was evaluated. The result showed that 732-type cation exchange resin was the better resin for decolorization of the TSPJ. The total saponin products with higher purity and quality were obtained, with the mass fraction more than 85.0%, and the transfer rate of TSPJ was more than 70.0%. Conclusion: The results show that the total saponins can be separated and purified effectively from P. japonicus. The preparation method is simple, effective, and efficient for large-scale preparation of TSPJ.

Preparation, Characterization, In Vitro Release and Taste-masking Effect of Paroxetine Resinate / 中国药学杂志

OBJECTIVE: To prepare and characterize paroxetine resinate, and evaluate the in vitro drug release rate and taste-masking effect. METHODS: A full factorial design was first conceived and applied to screen some process and formulation parameters (reaction temperature, stirring speed, drug concentration in solution and the ratio of resin to drug) on the key responses of resinationprocess, such as drug utilization ratio, drug loading and complexation constant. The paroxetine resinate was then characterized and evaluated by scanning electronic microscope (SEM), differential scanning calorimetry (DSC), in vitro drug release test and panel test of taste-masking. RESULTS: The resin/drug ratio and reaction temperature were identified as the most important factors on paroxetine resinate preparation.The drug-resin complex was successfully formed via ion exchange mechanism rather than physical absorption with complete in vitro drug release (>96%) in acidic or salt solution and good taste-masking effect. CONCLUSION: Paroxetine resinate with good performance can be prepared via optimization of process and formulation parameters, which will facilitate the development of generic paroxetine suspension.

Preparation and quality assessment of high-purity ginseng total saponins by ion exchange resin combined with macroporous adsorption resin separation / 中国天然药物

AIM@#To prepare high-purity ginseng total saponins from a water decoction of Chinese ginseng root.@*METHOD@#Total saponins were efficiently purified by dynamic anion-cation exchange following the removal of hydrophilic impurities by macroporous resin D101. For quality control, ultrahigh-performance liquid chromatography with a charged aerosol detector (CAD) was applied to quantify marker components. The total saponin content was estimated by a colorimetric method using a vanillin-vitriol system and CAD response.@*RESULTS@#D201, which consisted of a cross-linked polystyrene matrix and -N(+)(CH3)3 functional groups, was the best of the four anion exchange resins tested. However, no significant difference in cation exchange ability was observed between D001 (strong acid) and D113 (weak acid), although they have different functional groups and matrices. After purification in combination with D101, D201, and D113, the estimated contents of total saponins were 107% and 90% according to the colorimetric method and CAD response, respectively. The total amount of representative ginsenosides Re, Rd, Rg1, and compound K was approximately 22% based on ultrahigh-performance liquid chromatography-CAD quantitative analysis.@*CONCLUSION@#These findings suggest that an ion exchange resin, combined with macroporous adsorption resin separation, is a promising and feasible purification procedure for neutral natural polar components.

Isolation and purification of 5-hydroxytryptophan in extract from seeds of Griffonia simplicifolia by ion-exchange resin / 中草药

Objective: To research the adsortpion and separation function of ion-exchange resin on 5-hydroxytryptophan (5-HTP) in extract from the seeds of Griffonia simplicifolia and to screen the ion-exchange resin with high selective adsorption. Methods: The static adsorptive properties of eight different types of ion-exchange resins were evaluated using adsorptive content, desorption rate, adsorption rate, and adsorption temperature as indexes in order to optimize the resin. And the effects of different pH values, injection rates, injection concentration, eluent concentration, and elution rates on adsorptive properties of resins were investigated. Results: The 001 × 7 cation exchange resin showed the best comprehensive adsorption property. The loading solution concentration was 10.8 mg/mL, the pH value was 3.5, the flow rate of loading solution was 4.0 mL/min, and 3BV 7.0% ammonia water solution in 3.0 mL/min velocity was used to elute. In this process, the product was obtained with the 5-HTP purity of greater than 99.0% and the ash content of less than 1.0%, product average yield was 7.95% and the product quality could meet the market demand. Conclusion: The 001 × 7 cation exchange resin shows a better comprehensive adsorption property. It could be used to isolate and purify the 5-HTP for scale production.