South African Journal of Chemistry-Suid-Afrikaanse Tydskrif Vir Chemie最新文献_第2页

Removal of heavy metals from aqueous solutions by adsorption using natural and ammonium carbonate modified kaolinite clays 天然和碳酸铵改性高岭石粘土吸附去除水中重金属的研究

IF 1.5 4区化学 Q4 CHEMISTRY, MULTIDISCIPLINARY

South African Journal of Chemistry-Suid-Afrikaanse Tydskrif Vir Chemie

Pub Date : 2023-01-01 DOI: 10.17159/0379-4350/2023/v77a09

J. Lawal, E. Odebunmi, F. A. Adekola

Natural kaolinite obtained from Share, Nigeria was treated with ammonium carbonate to enhance the adsorption capacity. The optimum operating conditions for the adsorption of metal ions on the natural clay (SK clay) were employed on the ammonium carbonate-treated clay (SK-AC clay). The adsorption data were analysed using adsorption isotherm and kinetic models. The statistical p-values were less than 0.05, indicating that the model terms are significant for the adsorption of the metal ions. The pseudo-second-order kinetic model best describes the metal ions adsorption mechanism. The activation energy values less than 40 kJ mol-1 obtained indicated physisorption. Langmuir adsorption isotherm model fitted the adsorption data for Fe2+, Zn2+ and Cr6+ ions while the Freundlich model fitted Pb2+ ions adsorption. Analysis of thermodynamic parameters shows the adsorption is spontaneous and endothermic. The ammonium carbonate-modified clay exhibited an increase in adsorption capacity from 10.74 to 13.60 mg g-1, 16.48 to 17.38 mg g-1 and 11. 96 to 13.8 mg g-1 for Fe2+, Pb2+ and Zn2+ ions while uptake of Cr6+ decreased from 8.75 to 7.25 mg g-1. The results showed that the adsorption of Fe2+, Pb2+ and Zn2+ ions onto kaolin-containing cowlesite can be enhanced by treating it with ammonium carbonate.

采用碳酸铵处理尼日利亚Share天然高岭石，提高其吸附能力。将天然黏土(SK黏土)吸附金属离子的最佳操作条件应用于碳酸铵处理的黏土(SK- ac黏土)。采用吸附等温线和动力学模型对吸附数据进行了分析。统计p值小于0.05，表明模型项对金属离子的吸附是显著的。拟二级动力学模型最能描述金属离子的吸附机理。得到的活化能小于40 kJ mol-1，表明存在物理吸附。Langmuir吸附等温线模型拟合Fe2+、Zn2+和Cr6+离子的吸附数据，Freundlich模型拟合Pb2+离子的吸附数据。热力学参数分析表明，吸附是自发的吸热吸附。碳酸铵改性粘土的吸附量分别从10.74 ~ 13.60 mg g-1、16.48 ~ 17.38 mg g-1和11增加。Fe2+、Pb2+和Zn2+的吸收量为96 ~ 13.8 mg g-1, Cr6+的吸收量为8.75 ~ 7.25 mg g-1。结果表明，碳酸铵处理可增强含高岭土对Fe2+、Pb2+和Zn2+离子的吸附。

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引用次数: 0

Recyclable polymeric ionic liquids applied as metal-free transfer hydrogenation catalysts 可回收聚合物离子液体用作无金属转移加氢催化剂

IF 1.5 4区化学 Q4 CHEMISTRY, MULTIDISCIPLINARY

South African Journal of Chemistry-Suid-Afrikaanse Tydskrif Vir Chemie

Pub Date : 2022-12-01 DOI: 10.17159/0379-4350/2022/v76a17

G. Dhimba, M. Bala

A new methodology for immobilizing a triazolium salt onto polyethylene glycols (PEG) was developed. The immobilization is a two-step reaction, involving the tosylation of PEGs followed by a neat reaction between the PEG tosylates and the triazole. It is a high-yielding reaction conducted under mild conditions with a simple workup procedure. Hence, the salt 1-benzyl-4-phenyl-1H-1,2,3-triazolium iodide was immobilised onto PEGs of varying chain lengths (PEG300_8000) to yield various polymeric ionic liquids (PILs). All the PIL compounds were characterised by spectroscopic analysis and utilised as homogeneous metal-free organocatalysts for the transfer hydrogenation of ketones to alcohols in isopropanol as solvent and hydrogen source. The metal-free PIL catalysts showed activity for transforming acetophenone to 1-phenyl alcohol at up to 87% conversion. The representative PEG600 system was recycled three times with minimal loss in activity. The mechanism of a possible catalyst leaching was investigated using computational calculations. The results reveal that the promoter, isopropanol, also promotes the leaching of the triazole from the PEG backbone.

提出了一种三唑盐在聚乙二醇(PEG)上固定的新方法。固定化是一个两步反应，包括聚乙二醇的甲酰基化，然后是聚乙二醇甲酰基酸酯和三唑之间的整齐反应。这是一个在温和条件下进行的高收率反应，后处理程序简单。因此，将1-苄基-4-苯基- 1h -1,2,3-碘化三唑盐固定在不同链长的聚乙二醇(PEG300_8000)上，得到各种聚合物离子液体(PILs)。所有的PIL化合物都通过光谱分析进行了表征，并用作均相无金属有机催化剂，用于在异丙醇作为溶剂和氢源的情况下酮类转化为醇的氢化反应。无金属PIL催化剂将苯乙酮转化为1-苯醇的转化率高达87%。具有代表性的PEG600体系回收了三次，活动损失最小。用计算方法研究了一种可能的催化剂浸出机理。结果表明，促进剂异丙醇也能促进三唑从PEG主链中浸出。

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引用次数: 0

A detailed investigation of the structural stability, ionic conductivity and in situ δ-phase formation of YxBi2xO3 YxBi2xO3的结构稳定性、离子电导率和原位δ相形成的详细研究

IF 1.5 4区化学 Q4 CHEMISTRY, MULTIDISCIPLINARY

South African Journal of Chemistry-Suid-Afrikaanse Tydskrif Vir Chemie

Pub Date : 2022-12-01 DOI: 10.17159/0379-4350/2022/v76a16

M. Kiefer, C. Billing, R. Erasmu, W. Mogodi, D. Billing

The in situ δ-phase formation for a series of yttrium-doped Bi2O3 materials was studied by Raman spectroscopy and high resolution X-ray diffraction under variable temperature conditions. Contrary to previous reports, for dopant concentrations less than 25%, the cubic ô-phase was not fully stabilized at room temperature - tetragonal phase content was evident in both Raman spectra and powder diffractograms. Arrhenius plots also showed evidence of a phase transformation by the distinct large step change in conductivity in the temperature region where the tetragonal-cubic phase transformation was noted. Both the thermal expansion and ionic conductivity of the cubic phase decreased with increasing dopant content.

利用拉曼光谱和高分辨率x射线衍射研究了一系列掺钇Bi2O3材料在变温度条件下的原位δ相形成。与之前的报道相反，当掺杂浓度低于25%时，立方体ô-phase在室温下没有完全稳定-拉曼光谱和粉末衍射图中都明显存在四方相含量。Arrhenius图也显示了相变的证据，在注意到四方立方相变的温度区域，电导率明显的大阶跃变化。随着掺杂量的增加，立方相的热膨胀率和离子电导率均降低。

引用次数: 0

Pollution assessment of antimony in shooting range soils 射击场土壤中锑污染评价

IF 1.5 4区化学 Q4 CHEMISTRY, MULTIDISCIPLINARY

South African Journal of Chemistry-Suid-Afrikaanse Tydskrif Vir Chemie

Pub Date : 2022-12-01 DOI: 10.17159/0379-4350/2022/v76a11

Pogisego Dinake, S. Mokgosi, Rosemary Kelebemang, T. T. Kereeditse, Obakeng Motswetla

Soil samples collected from the berm at Thebephatshwa (TAB) shooting range found in Botswana showed variable total concentrations of antimony in the range 38±1 to 283±12 mg/kg. Total antimony concentrations found in the soils were higher than the set regulatory levels by the World Health Organization (36 mg/kg) and the United States Protection Agency (31 mg/kg). The upper berm showed elevated levels of antimony (283±12 mg/kg) due, in part, to the highest density of spent projectiles found in this part of the berm. Sequential extraction studies established that antimony was partitioned mostly in the organic and residual fractions of the soil. Environmental pollution risk assessment based on geoaccumulation index (Igeo), contamination factor (CF) and enrichment factor (EF) indicated all four sections of the berm posed high risk to the environment. The upper berm exhibited extreme pollution from antimony (Igeo ~9), very high contamination (CF ~744) and extreme antimony enrichment (EF ~506) compared to the other three sections studied. Elevated levels of antimony at TAB shooting range call for best shooting range management practices, soil remediation and reclamation methods to be carried out at this shooting range to minimize the mobility and bioavailability of antimony.

从博茨瓦纳Thebephatshwa (TAB)射靶场的护坡上采集的土壤样本显示，锑的总浓度在38±1至283±12毫克/公斤之间。土壤中发现的总锑浓度高于世界卫生组织(36毫克/公斤)和美国保护署(31毫克/公斤)规定的管制水平。上护堤显示锑水平升高(283±12毫克/公斤)，部分原因是在这部分护堤中发现的废弹密度最高。序贯提取研究表明，锑主要分布在土壤的有机组分和残余组分中。基于地质累积指数(Igeo)、污染因子(CF)和富集因子(EF)的环境污染风险评价表明，4个断面均存在较高的环境污染风险。与其他3个断面相比，上滩表现出严重的锑污染(Igeo ~9)，非常高的污染(CF ~744)和严重的锑富集(EF ~506)。TAB射击场锑含量升高，需要在该射击场实施最佳射击场管理措施、土壤修复和开垦方法，以尽量减少锑的流动性和生物利用度。

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引用次数: 1

Effect of a Hands-On Chemistry Intervention on the behavioural and effective attitudes of learners from low socio-economic high schools 动手化学干预对低社会经济高中学生行为和有效态度的影响

IF 1.5 4区化学 Q4 CHEMISTRY, MULTIDISCIPLINARY

South African Journal of Chemistry-Suid-Afrikaanse Tydskrif Vir Chemie

Pub Date : 2022-12-01 DOI: 10.17159/0379-4350/2022/v76a15

T. Swartbooi, G. Rubidge, M. Gibbs, E. Ferg

This research focused on the effect that three easily accessible, cost-effective, and hands-on chemistry experiments which are aligned to Curriculum Assessment Policy Statements (CAPS), had on Grade 9 learners from low socio-economic high schools. These experiments were conducted in an after-school science club format at two quintile-1 high schools situated in Gqeberha, South Africa. The learners' behavioural and affective attitudes were examined using group interviews (n = 6) and a survey (n = 61). The findings from this study showed that learners wanted to share knowledge with their peers and community after learning new scientific skills at the science-club. Learners also recognized the economic and practical importance of science related careers. Responses revealed that learners lose interest if the science does not actively connect or engage with their current circumstances. This study also showed that learners were further motivated to pursue studies in Physical Science in Grades 10 to 12.

这项研究的重点是三个容易获得、成本效益高、动手操作的化学实验，这些实验与课程评估政策声明（CAPS）相一致，对来自低社会经济水平高中的九年级学生产生了影响。这些实验是在位于南非Gqeberha的两所五年级一高中以课后科学俱乐部的形式进行的。学习者的行为和情感态度通过小组访谈（n=6）和调查（n=61）进行了检查。这项研究的结果表明，学习者在科学俱乐部学习新的科学技能后，希望与同龄人和社区分享知识。学习者还认识到与科学相关的职业在经济和实践方面的重要性。回答显示，如果科学不积极联系或参与他们当前的环境，学习者就会失去兴趣。这项研究还表明，学习者在10至12年级进一步有动力学习物理科学。

引用次数: 0

Effervescence assisted dispersive liquid-liquid microextraction for spectrophotometry determination of chromium (VI) in water, tannery effluent, milk, and orange juice samples 泡腾辅助分散液-液微萃取分光光度法测定水、制革废水、牛奶和橙汁样品中的铬（VI）

IF 1.5 4区化学 Q4 CHEMISTRY, MULTIDISCIPLINARY

South African Journal of Chemistry-Suid-Afrikaanse Tydskrif Vir Chemie

Pub Date : 2022-12-01 DOI: 10.17159/0379-4350/2022/v76a18

A. Kebede, G. Tilachew, G. Chirfa, A. Gure

In this paper, effervescence-assisted dispersive liquid-liquid microextraction was proposed for selective extraction and preconcentration of Cr (VI) prior to its quantitative determination by UV-Vis spectrophotometry. Before employing the method, Cr (VI) ions available in the samples were complexed with 1,5-diphenylcarbazide in an acidic medium. Experimental parameters influencing the performances of the method including pH, the concentration of the complexing agent, type and volume of both extraction solvent and effervescent agent, stability of the complex, and effect of extraction time were thoroughly studied and optimized. Calibration curve plotted from 0.005-2.0 mg L-1 demonstrated good linearity (R2 = 0.9992). The limits of detection and quantification of the method were 0.001 and 0.005 mg L-1, respectively. The method provided an enrichment factor of 21.4. Precision studies in terms of repeatability, intermediate precision, and reproducibility were conducted at three concentration levels and their RSD values were <6.2. The ruggedness of the method studied at different wavelengths (535-545 nm) had RSD values <3.3. The recoveries of the method were from 83.0-117.6%. Finally, the proposed method was successfully applied for the determination of Cr (VI) from various matrices including tap, well, and river water; tannery effluent; milk; and orange juice samples.

本文提出了在紫外-可见分光光度法定量测定Cr（VI）之前，采用泡腾辅助分散液-液微萃取法对Cr进行选择性萃取和预富集。在采用该方法之前，将样品中可用的Cr（VI）离子与1，5-二苯基咔唑在酸性介质中络合。对影响该方法性能的实验参数，包括pH、络合剂浓度、萃取溶剂和泡腾剂的类型和体积、络合物的稳定性以及萃取时间的影响进行了深入的研究和优化。在0.005-2.0 mg L-1范围内绘制的校准曲线显示出良好的线性（R2=0.992）。该方法的检测限和定量限分别为0.001和0.005 mg L-1。该方法提供了21.4的富集因子。在三个浓度水平下进行了重复性、中间精密度和再现性方面的精密度研究，其RSD值<6.2。在不同波长（535-545nm）下研究的方法的稳健性的RSD值<3.3。该方法的回收率为83.0-117.6%。最后，该方法成功地应用于自来水、井水和河水等各种基质中Cr（VI）的测定；制革废水；牛奶和橙汁样品。

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引用次数: 0

Patient Medication Preferences for Managing Dry Eye Disease: The Importance of Medication Side Effects. 患者对治疗干眼症药物的偏好：药物副作用的重要性。

4区化学 Q4 CHEMISTRY, MULTIDISCIPLINARY

South African Journal of Chemistry-Suid-Afrikaanse Tydskrif Vir Chemie

Pub Date : 2022-11-01 Epub Date: 2022-06-14 DOI: 10.1007/s40271-022-00586-8

Semra Ozdemir, Sharon Wan Jie Yeo, Jia Jia Lee, Adithya Bhaskar, Eric Finkelstein, Louis Tong

Objectives: The side effects of dry eye medications can lead to medication non-adherence and, eventually, to poor outcomes. This study aimed to quantify to what extent the side effects of dry eye disease (DED) medications (burning/stinging sensation and blurring) are important to patients compared to medication benefits or costs.

Methods: Patients diagnosed with DED were recruited at a referral eye center in Singapore (n = 139). This study utilized a Discrete Choice Experiment where patients were presented with 10 choice tasks where they were asked to choose between their current medication (or no medication), and two hypothetical medications that varied based on five attributes: duration of burning/stinging, duration of blurring, time to medication effectiveness, medication frequency, and out-of-pocket cost. The main outcomes were relative attribute importance and predicted uptake.

Results: Latent class logistic regressions found two groups with distinct preferences. For both classes, duration of burning/stinging (Class 1 = 23%, Class 2 = 29%) and cost (Class 1 = 24%, Class 2 = 27%) were the most important attributes while duration of blurring (Class 1 = 15%, Class 2 = 9%) was the least important. The predicted uptake of a medication increased 18 percentage-points when burning/stinging duration decreased from 2 h to a few minutes. The predicted uptake for new medications was lowest for those on medication with well-controlled symptoms and highest for those who were not on medication and could not control their symptoms effectively.

Conclusion: This study showed that duration of burning/stinging was an important factor when choosing medications. Incorporating patient preferences in medication decisions can potentially improve patient acceptance of a treatment regimen.

目的：干眼症药物的副作用会导致患者不坚持用药，最终导致不良后果。本研究旨在量化干眼症（DED）药物的副作用（灼热/刺痛感和模糊）与药物疗效或成本相比，对患者的重要程度：在新加坡的一家眼科转诊中心招募了被诊断为干眼症的患者（n = 139）。本研究采用了离散选择实验，向患者展示了 10 个选择任务，要求他们在当前药物（或不用药）和两种假设药物中做出选择，这两种药物根据以下五个属性而有所不同：灼热/刺痛感持续时间、模糊持续时间、药物起效时间、用药频率和自付费用。主要结果是相对属性重要性和预测服用量：结果：潜类逻辑回归发现有两组人具有不同的偏好。对于这两类人来说，灼热/刺痛持续时间（1 类 = 23%，2 类 = 29%）和费用（1 类 = 24%，2 类 = 27%）是最重要的属性，而模糊持续时间（1 类 = 15%，2 类 = 9%）则是最不重要的属性。当灼烧/刺痛持续时间从 2 小时缩短到几分钟时，预测的药物吸收率增加了 18 个百分点。正在服药且症状控制良好的患者对新药的预测接受率最低，而未服药且无法有效控制症状的患者对新药的预测接受率最高：本研究表明，灼热/刺痛持续时间是选择药物时的一个重要因素。将患者的偏好纳入用药决策中可能会提高患者对治疗方案的接受度。

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引用次数: 0

The analysis of alcohol content in hand sanitisers (in the Durban region) using gas chromatography-mass spectrometry during the COVID-19 pandemic 在COVID-19大流行期间使用气相色谱-质谱法分析(德班地区)洗手液中的酒精含量

IF 1.5 4区化学 Q4 CHEMISTRY, MULTIDISCIPLINARY

South African Journal of Chemistry-Suid-Afrikaanse Tydskrif Vir Chemie

Pub Date : 2022-01-01 DOI: 10.17159/0379-4350/2022/v76a04

Kamini Govender, Sipho Mdanda, S. Baijnath, H. Kruger, T. Govender, Tricia Naicker

ABSTRACT The COVID-19 pandemic has resulted in an unprecedented surge in the demand for alcohol-based hand sanitisers (ABHS). The Centre for Disease Control (CDC) and World Health Organisation (WHO) recommend alcohol, i.e., isopropanol or ethanol, at a 60-95% concentration in ABHS for sufficient antiviral protection. Consumers need to be vigilant of substandard hand sanitisers being marketed to the public. The frequent exposure of microorganisms to alcohol concentrations below the recommended range for infection prevention may lead to resistant mutations, and above the range may be ineffective. Therefore, this study aimed to verify the stated alcohol content in hand sanitisers from their respective labels. We analysed 50 hand sanitiser samples available to our region in Durban, KwaZulu-Natal, South Africa, using a Shimadzu GC-MS-QP2010 Ultra equipped with a Zebron ZB-wax capillary column. The hand sanitisers analysed had a range of 44-93% alcohol content. The data from our study also revealed that 32% (16) of hand sanitisers did not adhere to the stated alcohol indicated on their labels. 16% (8) contained >80% and 12% (6) contained <60%, while 6% (3) of the ABHS contained 1-propanol and ethyl acetate as contaminants, respectively. This study clearly emphasises manufacturers' exploitation of the pandemic and the need for stricter guidelines and regulations for consistency amongst ABHS manufacturers. The public should also be more alert to the % alcohol stated (ideal range 60-80%) on the sanitizer bottle and note one needs to rub their hands together until it feels dry. Keywords: alcohol-content, ethanol, gas chromatography-mass spectrometry, hand sanitiser, 2-propanol (isopropanol)

2019冠状病毒病大流行导致对含酒精洗手液(ABHS)的需求空前激增。疾病控制中心(CDC)和世界卫生组织(WHO)建议使用酒精，即异丙醇或乙醇，在ABHS中浓度为60-95%，以获得足够的抗病毒保护。消费者需要警惕销售给公众的不合格洗手液。经常将微生物暴露于低于预防感染建议范围的酒精浓度可能导致耐药突变，高于该范围可能无效。因此，本研究旨在验证洗手液各自标签中所述的酒精含量。我们使用配备Zebron zb蜡毛细管柱的岛津GC-MS-QP2010 Ultra分析了南非夸祖鲁-纳塔尔省德班地区可获得的50份洗手液样本。被分析的洗手液酒精含量在44-93%之间。我们的研究数据还显示，32%(16)的洗手液不符合其标签上注明的酒精含量。16%(8)和12%(6)的ABHS污染物含量<60%，6%(3)的ABHS污染物分别为1-丙醇和乙酸乙酯。这项研究明确强调了制造商利用大流行的情况，以及需要制定更严格的指导方针和法规，以确保ABHS制造商之间的一致性。公众也应该更加警惕洗手液瓶子上的酒精含量(理想范围为60-80%)，并注意人们需要相互摩擦双手直到感觉干燥。关键词:醇含量，乙醇，气相色谱-质谱法，洗手液，2-丙醇(异丙醇)

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引用次数: 3

Potentiometrie and spectroscopic study of isoniazid - an anti-tubercular drug 抗结核药物异烟肼的电位及光谱研究

IF 1.5 4区化学 Q4 CHEMISTRY, MULTIDISCIPLINARY

South African Journal of Chemistry-Suid-Afrikaanse Tydskrif Vir Chemie

Pub Date : 2022-01-01 DOI: 10.17159/0379-4350/2022/v76a10

D. Tolulope, G. Jackson, M. Caira, A. Hammouda

The copper, nickel and zinc complexes of isoniazid (ISO, isonicotinic acid hydrazide), an anti-tubercular drug, have been investigated to determine whether these metal-ions improve the permeability and bioavailability of the drug. Since such properties of isonazid depend on its solution speciation, the latter was investigated by determining the equilibrium constants for the reaction of H+, Cu(II), Ni(II) and Zn(II) with isonazid in aqueous solution at 25.00 ± 0.01 °C and 0.15 M (NaCl), using glass electrode potentiometry. The structure of the copper complex of isoniazid was investigated using ultraviolet-visible spectroscopy. The results support the structures postulated from the potentiometric data. This study also considered membrane permeability using a Franz cell and octanol/water distribution coefficients. Distribution coefficient studies showed that ISO and its metal complexes are hydrophilic. The incorporation of a metal-ion improves the hydrophilicity of the ligand. The presence of a metal ion greatly enhanced the permeation of ISO through an artificial membrane in the order Cu(II) > Ni(II) > Zn(II) > ISO at pH 2 and Zn(II) > Ni(II) > ISO > Cu(II) at pH 4.

本文研究了抗结核药物异烟肼(ISO，异烟酸肼)的铜、镍和锌配合物，以确定这些金属离子是否能改善药物的渗透性和生物利用度。由于异烟肼的这些性质取决于其溶液形态，因此采用玻璃电极电位法测定了H+、Cu(II)、Ni(II)和Zn(II)与异烟肼在25.00±0.01℃和0.15 M (NaCl)水溶液中的反应平衡常数。用紫外-可见光谱法研究了异烟肼铜配合物的结构。结果支持了电位数据所假设的结构。本研究还考虑了使用Franz细胞和辛醇/水分布系数的膜通透性。分布系数研究表明，ISO及其金属配合物具有亲水性。金属离子的掺入提高了配体的亲水性。金属离子的存在极大地增强了ISO通过人工膜的渗透，在pH为2时，其渗透顺序为Cu(II) > Ni(II) > Zn(II) > ISO，在pH为4时，其渗透顺序为Zn(II) > Ni(II) > ISO > Cu(II)。

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引用次数: 0

Synthesis, characterisation and optimisation of bulk molecularly imprinted polymers from nonsteroidal anti-inflammatory drugs 非甾体抗炎药分子印迹聚合物的合成、表征和优化

IF 1.5 4区化学 Q4 CHEMISTRY, MULTIDISCIPLINARY

South African Journal of Chemistry-Suid-Afrikaanse Tydskrif Vir Chemie

Pub Date : 2022-01-01 DOI: 10.17159/0379-4350/2022/v76a09

S. Nkosi, P. Mahlambi, L. Chimuka

The scope of this study was to synthesise and characterise the multi-template molecularly imprinted polymer (MIP) and to use target compounds, naproxen, ibuprofen, diclofenac, fenoprofen and gemfibrozil as templates so as to achieve all maximum extraction efficiency for all compounds. These compounds are a class of nonsteroidal anti-inflammatory drugs (NSAIDs) generally used by humans, as they have pain-relieving activities. MIPs are cross-linked polymeric materials that display high binding capacity and selectivity towards templates of interest. The synthesis consisted of a bulk polymerisation process at 60 °C by using NSAIDs as multi-templates, ethylene glycol dimethacrylate (EGDMA), 2-vinyl pyridine (2VP) and toluene as cross-linker, functional monomer and porogen, respectively. Nonimprinted polymer (NIP) was synthesised in a similar manner with the omission of the templates. Characteristics of the polymers were analysed using Scanning Electron Microscopy (SEM), Fourier Transformed Infrared Spectroscopy (FTIR), Solid State Nuclear Magnetic Resonance Spectroscopy (NMR) and Thermal Gravimetric Analysis (TGA). An adsorption method of NSAIDs using the bulk polymerised MIP was investigated under various pH, mass, concentration and time conditions. Other parameters included adsorption kinetics and adsorption isotherms. Uptake of NSAIDs from an aqueous medium was achieved with 40 mg of MIP at pH 4.0 within 10 min of contact time. The extraction efficiencies achieved for NSAIDs in aqueous solutions ranged from 90–98% for all compounds tested. The adsorption capacity obtained for MIP ranged from 1.230–1.249 mg g−1 and 0.90–1.136 mg g−1 for NIP, whereas the selectivity values ranged from 1.12–2.4. A kinetic study revealed that adsorption obeys a second-order rate, and the Langmuir model explains adsorption isotherm data. This work showed that the multi-template approach for all the target compounds has the potential to give maximum extraction efficiencies in MIP extraction systems from aqueous samples.

本研究的范围是合成和表征多模板分子印迹聚合物(MIP)，并以目标化合物萘普生、布洛芬、双氯芬酸、非诺洛芬和吉非罗齐为模板，以达到所有化合物的最大提取效率。这些化合物是一类非甾体类抗炎药(NSAIDs)，通常被人类使用，因为它们具有缓解疼痛的活性。mip是一种交联聚合物材料，对感兴趣的模板具有高的结合能力和选择性。以非甾体抗炎药为多模板剂，乙二醇二甲基丙烯酸酯(EGDMA)、2-乙烯基吡啶(2VP)和甲苯为交联剂、功能单体和多孔剂，在60℃下进行本体聚合。非印迹聚合物(NIP)以类似的方式合成，省略模板。采用扫描电子显微镜(SEM)、傅里叶变换红外光谱(FTIR)、固体核磁共振光谱(NMR)和热重分析(TGA)分析了聚合物的特征。在不同的pH、质量、浓度和时间条件下，研究了本体聚合MIP吸附非甾体抗炎药的方法。其他参数包括吸附动力学和吸附等温线。在接触时间10分钟内，在pH 4.0条件下，用40 mg MIP从水介质中摄取非甾体抗炎药。非甾体抗炎药在水溶液中的萃取效率在90-98%之间。MIP的吸附量为1.230 ~ 1.249 mg g−1,NIP的吸附量为0.90 ~ 1.136 mg g−1，选择性为1.12 ~ 2.4。动力学研究表明，吸附服从二阶速率，Langmuir模型解释了吸附等温线数据。这项工作表明，对所有目标化合物的多模板方法有可能在MIP萃取系统中从水样品中获得最大的萃取效率。

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引用次数: 2