沉淀聚合法制备磺胺二甲嘧啶分子印迹聚合物

以磺胺二甲嘧啶为模板分子,采用沉淀聚合法制备了分子印迹聚合物,并对其选择性和吸附性能进行了研究.等温静态平衡实验结果表明,该印迹聚合物与相应的空白聚合物相比具有高的选择性和亲和性;Scatchard模型分析结果表明,该印迹聚合物对印迹分子存在一种均匀的结合位点,最大表观结合量为31.866 mg/g.     

In vitro solubilization of antibiotic drug sulfamethazine: An investigation on drug–micelle aggregate formation by spectroscopic and scattering techniques

Micellar solubilization has been used extensively for the dissolution of sparingly soluble drugs for effective drug delivery. Apart from improving the solubility and bioavailability, micelles can help reduce toxicity and improve permeability in the system. In this article, solubilization of a well-known antibiotic, sulfamethazine (SMZ) upon micellization, is studied by employing various spectroscopic and scattering techniques like, ultraviolet–visible, fluorescence, small angle neutron scattering (SANS), and zeta potential (ZP) studies. The size(s) and charge(s) of the micelles were monitored by SANS and ZP. A positively charged/cationic surfactant, cetyl trimethyl ammonium bromide (CTAB) and a negatively charged/anionic surfactant, sodium dodecyl sulfate (SDS) are used for micelle formation. Regardless of the surfactant type, the solubility of SMZ increases linearly with the increase in the surfactant concentration, as a result of association between the drug and micelles. However, the solubility of SMZ is found to be better with CTAB than SDS. Upon interaction with SMZ, we observed that the critical micelle concentration of CTAB occurred at a lower concentration than that of SDS surfactant. As fitted in the ellipsoidal core–shell model, SANS results also show the formation of charged micelles. This comparative study can help us to select an appropriate medium for SMZ solubilization to improve selective drug delivery in biomedical applications.     

Development of a Monoclonal Antibody-based ELISA for Detection of Sulfamethazine and N4−acetyl Sulfamethazine in Chicken Breast Muscle Tissue

ABSTRACT: An anti-sulfamethazine monoclonal antibody was developed in a BALB/c mouse immunized with sulfamethazine (SM₂) -human serum albumin (HSA). Using this monoclonal antibody, an indirect competitive enzyme-linked immunosorbent assay (cELISA) was developed to detect SM₂ and its metabolites in chicken breast muscle tissue. The 50% inhibition value (IC₅₀) was 9.3 ng/mL. When SM₂ was spiked at levels of 20 to 200 ng/g, recoveries ranged from 81.3% to 104.2% with coefficients of variation (CVs) of 4.3% to 19.3%. The metabolite N⁴−acetyl SM₂ was also evaluated by the same assay. When it was fortified atlevels of 20 to 200 ng/g, recoveries ranged from 80.4% to 100.8% with CVs of 3.0% to 14.2%. The results were confirmed with analysis by high-performance liquid chromatography (HPLC). In an actual residue study, the results obtained by cELISA did not correlate well with those obtained by HPLC ( P < 0.05). This might be due to the coextraction of cross-reactive SM₂-related residues that were not quantified by the HPLC method. The study indicated that the presence of residues should be anticipated when considering the maximum residue limit of SM₂ residue.     

磺胺二甲嘧啶人工抗原的合成与鉴定

采用重氮化法将磺胺二甲嘧啶(SM2)与牛血清白蛋白(BSA)和卵清蛋白(OVA)交联合成人工抗原SM2-BSA与SM2-OVA,并通过紫外扫描、SDS-PAGE电泳、凝胶层析和红外光谱等方法扫描进一步检测合成效果.紫外扫描检测结果显示,SM2与BSA、OVA偶联成功,SM2-BSA与SM2-OVA的特征波长分别为2762、77 nm;经计算SM2-BSA与SM2-OVA的分子结合比例分别为5.3∶1和18.4∶1;SDS-PAGE电泳迁移率、凝胶层析出峰时间和红外光谱曲线特征均显示SM2与BSA、OVA偶联成功.     

UASB-SBR工艺去除生活污水中磺胺二甲基嘧啶的试验研究

研究了UASB-SBR工艺对生活污水中磺胺二甲基嘧啶(SM2)的去除特性,并且在兼顾去除SM2和脱氮除磷的基础上,对工艺参数进行了优化。试验结果表明,UASB-SBR工艺对SM2有较好的去除效果,当温度为20℃,UASB反应器水力停留时间(HRT)为8 h,COD容积负荷为0.5～1.2 kg.m-.3d-1,进水pH在7.0～8.0时,COD、SM2平均去除率分别为70%、35%。在氮磷及SM2去除效果不佳的情况下,后续SBR反应器,当曝气时间为3 h,污泥龄(SRT)为20 d时,COD、TN、TP出水浓度均达到城镇污水处理厂污染物排放标准(GB 18918-2002)中的一级标准,SM2出水质量浓度为5～8μg·L-1,SM2总去除率为90%。厌氧段和好氧段对SM2的平均去除率分别为35%和55%,这说明SM2在好氧条件下更容易被降解。     

Oxidative degradation of sulfamethazine in aqueous solution by the activation of Na2S2O8 over vinasse-derived N,S-codoped mesoporous carbon

N,S-codoped mesoporous carbon (S/NMC) as an effective catalyst toward the catalytic persulfate oxidation of sulfamethazine (SMZ) was fabricated conveniently using vinasse as the C/N source, Na₂S as the S precursor and nano-SiO₂ as the template, respectively. The effect of S precursor dosage on the textural properties and surface chemistry of S/NMCs were characterized by N₂ adsorption/desorption, Raman spectra, X-ray diffractometer (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). It was found that more S precursor dosage presented an enhanced SMZ degradation performance due to the significant role of more S precursor dosage: (i) larger specific surface area and (ii) more active surface groups including pyridine N, graphite N, quinone-like O and thiophene-like S. In addition, quenching experiments showed that free radical and nonradical oxidation processes are the main processes of SMZ degradation. The findings provided a new idea for the resource utilization of vinasse and the development of catalytic persulfate oxidation of organic pollution.