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Adsorption of oxytetracycline and ciprofloxacin on carbon-based nanomaterials as affected by pH

Gamoń Filip, Tomaszewski Mariusz, Cema Grzegorz, Ziembińska-Buczyńska Aleksandra

Archives of Environmental Protection

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2022

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Vol. 48, no. 2

34--41

EN

With the increase in use and application of carbon nanomaterials and the frequent presence of fluoroquinolones and tetracyclines antibiotics in the aquatic environment, their interactions have attracted extensive attention. In this study, adsorption of two antibiotics: oxytetracycline (OTC) and ciprofloxacin (CIP) by four carbon-based nanomaterials (graphene oxide, reduced graphene oxide, multiwalled carbon-nanotubes, oxidized multiwalled carbon-nanotubes) affected by pH was investigated. The experiment was performed in two steps: (i) adsorption of OTC and CIP at different pH values, (ii) adsorption isotherm studies of both antibiotics on four carbon-based nanomaterials. Both steps were conducted using the batch equilibration technique. The results showed that the adsorption of both antibiotics on studied adsorbents was highly pH-dependent. The highest adsorption was obtained at pH 7.0, implying the importance of the zwitterionic antibiotics forms to adsorption. Antibiotics adsorption isotherms at three given pH values followed the order of pH 7.0 > 1.0 > 11.0, which confirmed zwitterionic species of OTC and CIP as having the greatest ability to adsorb on carbonaceous nanomaterials. Electrostatic interaction, π-π EDA interaction, hydrophobic interaction for both antibiotics, and additionally hydrogen bond for CIP were possible mechanisms responsible for OTC and CIP adsorption onto studied nanomaterials. These results should be important to understand and assess the fate and interaction of carbon-based nanomaterials in the aquatic environment. This study can also be important for the use of carbon nanomaterials to remove antibiotics from the environment.

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Determination of tetracycline, oxytetracycline and chlortetracycline in milk by TLC and column chromatography using Amberlite XAD-2

Petkovska E., Slaveska-Raicki R., Rafajlovska V.

Chemia Analityczna

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2006

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Vol. 51, No. 2

275-283

EN

In solid biological samples selected cations and anions have been determined by ion chro-matography (1C). Before the analysis, single preparation step has been applied. The proposed procedure allowed one to determine concentration of alkali and alkaline cations (Na+, K+, Mg2+, Ca2+), as well as anions (Cl-, Br-

PL

Zaproponowano procedure przygotowania stałych próbek biologicznych umożliwiającą oznaczanie kationów (Na+, K+ Mg2+, Ca2+) i anionów (Cl-, Br-) w tym samym roztworze metodą wysokosprawnej chromatografii jonowej z detekcjąkonduktomctryczną. Pomiary wykonano używając dwóch kolumn chromatograficznych (z fazami stacjonarnymi zawierającymi grupy sulfonową) trimetyloaminową) oraz trzech eluentów w trybie elucji izokratycznej. Walidację metody przeprowadzono za pomocą analizy certyfikowanego materiału odniesienia (cotton cellulose, IAEA V-9). Metodę zastosowano do analizy próbek różnych gatunków drewna.

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A study on oxytetracycline-human serum albumin interaction based on flow-injection chemiluminescence analysis combined with ultrafiltration sampling

Wang L.

Chemia Analityczna

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2006

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Vol. 51, No. 2

211-219

EN

Binding properties of oxytetracycline (OTC) and human serum albumin (HSA) have been studied in details. This investigation was based on flow injection che m i luminescence (FI-CL) analysis and ultrafiltration (UF) sampling technique. Chemiluminescence (CL) emission was observed during oxidation of OTC with KMnO4 in acidic medium in the presence of formaldehyde as a sensitizer. Coupled with flow injection technique, OTC can be determined in the range of 80x10-7-1,2x10-4mol L-1.Oxytetracycline and HSA weremixed in different molar ratios and incubated at 37š0.5°C. An ultrafiltration probe was introduced to the sample containing unbound drug and the concentration of this free drug was determined by the CL method. The obtained data were analysed applying the Scatchard plot. The binding constant (K) and the number of binding sites (n) were 3.19 x 104(mol L-1 and 1.10. respectively.

PL

Badano zdolność wiązania oksytetracykliny (OTC) przez albuminę osocza ludzkiego (HSA). Badania prowadzono metodą analizy wstrzykowej z detekcją chemiluminescencyjną (FI-CL). a próbki pobierano za pomocą ultrafiltracji. Chemiluminescencję obserwowano w trakcie utleniania OTC za pomocą KMnOsub>4 w obecności formaldehydu jako czynnika zwiększającego czułość reakcji. Metoda pozwala na oznaczanie OTC w zakresie stężeń: 80x10-7-1,2x10-4mol L-1. Oksytetracykline i HSA mieszano w różnych stosunkach molowych i utrzymywano w temperaturze 37š0.5°C. Sondę ultra filtracyjną wprowadzano do próbki zawierającej lek niezwiązany i stężenie tego leku oznaczano metodą CL. Dane analizowano stosując wykres Scatchard'a. Wyznaczono stałą wiązania (K): 3 x 104 (mol L-1 i liczbę miejsc wiązania (n): 1.10.

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Response of enchytraeid community (Oligochaeta, Enchytraeidae) to manipulation of microbial biomass

Nowak E., Piotrowska-Seget Z., Chmielewski K.

Polish Journal of Ecology

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2005

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Vol. 53, nr 1

53-63

EN

The paper describes a field experiment with the application of two biocides: oxytetracycline that reduced bacteria and captan that reduced soil fungi. The purpose of the experiment was to investigate the response of enchytraeid species to the changes of the abundance and activity of the microbial community as part of their food resources. The following variables were recorded: the biomass of microorganisms by the PLFA method, the rate of cellulose decomposition and the numbers and species composition of enchytraeids. No relationship was found betweenenchytraeids and abundance of microorganisms, but numbers of animals were correlated with changes in soil cellulolytic activity. Both biocides, even the non toxic oxytetracycline, reduced the diversity (H') of enchytraeid community by increasing the proportion of dominant species. It is suggested that biocides reduced the functional diversity of microorganisms, and this factor had an effect on the enchytraeid populations. The animals responded to the treatment and their community became predominanted by the species probably with a broad food spectrum.