With the emergence of the industrial age, the growing concern over environmental pollution has been to drug resistance in humans due to the use of antibiotics and their discharge in environment. The aim of this work was to synthesis of a carbon ceramic composite based on molecular imprinted polymers (MIP) particles via non-covalent procedure as selective adsorbent for removal of Cloxacillin (CLO) antibiotic from aqueous and biological media (MILK). The effect of operational parameters includes pH (3-10), contact time (1-120 min), MIP (0.1 – 5.0 %wt) and adsorbent dosage (0.1- 2.0 g/L) was studied for optimization of CLO removal condition. The synthesized MIP particles and fabricated carbon composites were characterized using scanning electron microscopy and nitrogen absorption/desorption (BET). The results showed that the removal efficiency was highest in neutral conditions and increased as amount of MIP particles increased. The optimum conditions for removal of CLO (94%) were determined at pH = 6.5, 87 minutes as contact time and the 1.6 g/L carbon composite contain 3.1 % wt MIP. The performance of the synthesized composites was evaluated for Cloxacillin removal from the milk sample. The performance of the MIP particles for the Cloxacillin removal of milk samples supplied from livestock showed that these adsorbents can help to effectively reduce the residues of drug contamination in dairy samples. تفاصيل المقالة

In this study, we tried to present an efficient method for removal of Reactive red 241 (RR241) from aqueous media, using a modified carbon composite with GO sheets. The prepared nanocomposites were then charcterizded by commonly identical techniques involve FESEM, BET and FT-IR. In removal studies, various parameters affecting the adsorption process including pH, time, adsorbent dose, temperature as well as the amount of GO in the constraction of composite were studied by respond surface method. The optimum conditions for removal of 100 mg/L of dye was pH of 5.0, time of 75 minutes and the adsorbent dose of 1.47 g/L containing 4.15 wt.% of GO. The maximum removal of 96% was also achieved under optimum conditions. Experiments showed that the adsorption was more consistent with the Langmuir equations and the maximum adsorption under this model was 160 mg/g. The results of the removal experiments showed that the amount of the adsorbent, GO content and pH had a significant effect on RR241 removal. BET analysis indicated that the addition of GO to the carbon composite structure improved the pore size, total pore volume, and effective surface area of the composite. Also, isotherms, kinetics and thermodynamic studies of adsorption were depicted that Langmuir isotherm model, pseudo-second-order kinetic model and self-adsorption are suitable models for RR241dye adsorption. تفاصيل المقالة

پادزیست‌ها از نظر مصرف وسعت جهانی داشته و پس از استفاده به شیوه‌های متفاوتی به منابع آبی راه می‌یابند. وجود مقادیر کم از این ترکیبات در آب و پساب می‌تواند باعث برهم‌زدن نظم دگرگشتی بدن جانداران ساکن در بوم‌سازگان شود. درنتیجه شناسایی و تشخیص مقادیر بسیار کم این ماده از اهمیت بالایی برخوردار است. در این پژوهش، یک حسگر الکتروشیمیایی برپایه بسپار قالب مولکولی و نانولوله‌های کربنی چنددیواره برای شناسایی و اندازه‌گیری پازیست مترونیدازول (MTN) در نمونه‌های حقیقی طراحی و ساخته شد. در طی این بررسی، اثر عوامل متفاوت شامل زمان اقامت حسگر در محلول پیش‌تغلیظ و pH آن بررسی شد. همچنین، تأثیر مقدار بسپار قالب‌مولکولی و مقدار نانولوله‌های کربنی چنددیواره در ساخت حسگر مورد بررسی قرار گرفت. شرایط عملیاتی بهینه برای ساخت حسگر شامل 105/0گرم بسپار قالب‌مولکولی، 0033/0 گرم نانولوله‌های کربنی چنددیواره، pH محلول پیش‌تغلیظ برابر با 0/8 و مدت فرایند پیش‌تغلیظ MTN در سطح الکترود خمیر کربن اصلاح‌شده با بسپار قالب‌مولکولی برابر با 26 دقیقه تعیین شد. حد تعیین nM 6/55 و گستره خطی 50 تا nM 1200 برای اندازه‌گیری مترونیدازول در سطح الکترود ساخته‌شده به‌دست آمد. الکترود اصلاح‌شده با بسپار قالب‌مولکولی و نانولوله‌های کربنی به صورت موفقیت‌آمیز برای جداسازی و سنجش MTN در نمونه‌های حقیقی مورداستفاده قرار گرفت. تفاصيل المقالة