Separation Of Tetracycline Research Articles

Fabrication of magnetic molecularly imprinted polymers based on aptamers and β-cyclodextrin for synergistic recognition and separation of tetracycline

Tetracycline is extensively used as an antibiotic in animal husbandry, and there arose an increase in antibiotic resistance genes in the environment, posing a threat to human health. Motivated by this, a magnetic molecularly imprinted material based on synergistic recognition (1 + 1>2) was constructed and coupled with high-performance liquid chromatography to detect ultra-trace tetracycline in complicated samples. In this case, the molecularly imprinted polymers were synthesized via a “one-pot” method and acted as recognition elements on the surface of silica-coated ferroferric oxide particles. Aptamers and β-cyclodextrin, as functional monomers, had a synergistic effect on the recognition of tetracycline and the synergistic recognition factor was 1.7. Meanwhile, the material exhibited high selectivity to tetracycline with an imprinting factor of 7.6. In addition, compared to being modified on the surface, the stability of the aptamers was effectively improved by cross-linking in the molecularly imprinted polymer framework. Relevant experimental conditions, such as buffers, concentration of magnesium ions and adsorption time, were optimized. As a result, the method showed a limit of detection of 1.0 μg L−1 and the linearity range of 0.005–0.5 mg L−1, as well as certain reproducibility and stability. Furthermore, when applied for the analysis of animal feed samples, a significant reduction of matrix interference was observed with satisfactory recoveries (85.0–111.5%), which emphasized the good accuracy and practicability of the established method. For these advantages, the proposed method represents a versatile and powerful tool for the separation and detection of small molecule compounds in complicated real samples.

Biomass-Based Synthesis of Green and Biodegradable Molecularly Imprinted Membranes for Selective Recognition and Separation of Tetracycline

Aggravating environmental problems have driven the unprecedented development of sustainable materials. Treatments of environmental pollutants with biomass-based sustainable materials are catching attention of more researchers. In the present work, a biomass-based strategy was developed to prepare sustainable molecularly imprinted nanocomposite membranes (S-MINMs). Based on this strategy, biomass-activated carbon nanoparticles (ACNPs) as the porous filler were integrated into the porous cellulose acetate (CA)/chitosan (CS) hybrid membranes to synthesize renewable and easy degradable basal membranes. The specific recognition sites were fabricated from simple free radical polymerization method, and using methacrylic acid (MAA) and acrylamide (Am) as functional monomers, we obtain improved adsorption capacity on tetracycline (TC, template molecule). Performance of S-MINMs was evaluated by adsorption isotherm, adsorption kinetics, perm-selectivity, reusability and biodegradability. Results indicated that the as-prepared S-MINMs not only exhibited desirable biodegradability, but also possess superior adsorption and separation performance toward TC (15.99[Formula: see text]mg g[Formula: see text] for adsorption capacity and 4.91 for perms-selectivity factor). The method developed here shows great potential for development of sustainable membranes for selective separation of various pollutants.

Separation of tetracycline from wastewater using forward osmosis process with thin film composite membrane – Implications for antibiotics recovery

Abstract To minimize the risk of antibiotic wastewater generated by the pharmaceutical industries, the potential separation efficacy of tetracycline (TC) from aqueous solution using forward osmosis (FO) process with thin film composite membrane was systematically studied. First, the microstructure and transport properties of TFC membrane were characterized. Then, the effects of membrane orientation, feed velocity and solution pH on the behavior of the FO process for TC separation were studied. Finally, the performance of TFC membrane for TC separation in a long-term FO mode operation was investigated. The results showed that the membrane performance in FO mode (active layer facing the feed solution) and PRO mode (active layer facing the draw solution) was highly affected by solute resistivity ( K ) value. The water flux and TC rejection achieved over 20 LMH and 99.0% in FO mode, respectively. High TC concentration factor (CF) of 2.6 was obtained in FO mode, indicating the concentrated TC solution could be harnessed to recover the TC by conventional crystallization. However, severe water flux decline accompanied with low tetracycline CF was found in PRO mode, which was mainly attributed to serious fouling and high K value occurred in the porous support. With the flow velocity rising, the shear stress and mass transfer coefficient ( k ) on the membrane surface increased, alleviating the membrane fouling. Acidic environment would favor the separation due to the change of TC speciation and TFC membrane properties. A long-term testing demonstrated that more than 97% TC rejection and 74% water flux recovery were well maintained with simple hydraulic cleaning after 5 cycles FO mode operation. This work implied that the FO based technology could be developed as an effective alternative for the treatment of tetracycline antibiotic wastewater as well as the recovery of antibiotics from the wastewater.

Determinative and confirmatory method for residues of tetracyclines in honey by LC-MS/MS

A limited number of substances are authorised for the treatment of bees. Maximum residue limits (MRLs) are set for tetracyclines in several matrices, but not for honey. Nevertheless, tetracycline antibiotics may be used in order to prevent bacterial diseases and the loss of honey bee populations. In this study, a sensitive multi-residue LC-MS/MS method was developed and optimised for the quantitative and qualitative determination of tetracycline residues in honey. Homogenisation of samples under acidic conditions was performed and solid-phase extraction was carried out. The eluate was evaporated under nitrogen and dissolved in an aqueous methanol solution prior to filtration. A mobile phase composed of acetic acid–water and acetic acid–acetonitrile was used. Separation of tetracycline, oxytetracycline, chlortetracycline and doxytetracycline was achieved by using gradient elution on a C18 chromatography column. The analytical method was validated according to Commission Decision 2002/657/EC by the analysis of spiked samples around the recommended concentration of 20 μg kg−1 by EURL Guidance Paper, December 2007. A matrix effect was observed, so quantification was based on an external matrix calibration curve. Calculated decision limits (CCα) were lower than 10 μg kg–1 for all tetracyclines. Good linearity, repeatability and within-laboratory reproducibility were achieved.

Finding an Alternative Column for the Separation of Antibiotics on XTerra RP using a Column Classification System

A project to develop a test procedure to characterize reversed‐phase liquid chromatographic C18 columns was started earlier and resulted in a fast, simple, repeatable, and reproducible test procedure. In this paper, the separations of two antibiotics (erythromycin and tetracycline) from their respective impurities were examined. Both methods were developed on XTerra RP, a hybrid column. The performance of the column classification system was evaluated by finding an alternative column for the XTerra RP column. The column classification system was helpful in the selection of a suitable column for the separation of erythromycin, but also showed its limitations towards the separation of tetracycline. The addition of an efficiency parameter and/or omission of one of the original parameters did not improve the results.

Separation of tetracycline and its potential impurities by liquid chromatography on XTerra RP-18

A linear gradient elution method is described for the separation of tetracycline, its fermentation impurities, and its degradation products. This method uses XTerra RP-18, 5 μm (25 cm×4.6 mm ID), a silica-based stationary phase with reduced silanol activity. Gradient elution with mobile phases containing acetonitrile, 0.3 M tetrabutylammonium hydrogen sulfate pH 7.5, 0.3 M ethylenediaminetetraacetic acid pH 7.5, water was used at a flow rate of 1.0 mL/min. The column temperature was set at 40°C. The UV detection was performed at 280 nm. A central composite experimental design was performed to optimize the separation. The method permits a good separation of TC and its impurities. Some of these were not reported before and have now been identified for the first time. Some unidentified impurities were also separated.

Separation of tetracycline and its related substances: comparison of liquid chromatography, capillary electrophoresis and capillary electrochromatography

Separation of tetracycline and its related substances: comparison of liquid chromatography, capillary electrophoresis and capillary electrochromatography

Separation of tetracycline and its related substances: comparison of liquid chromatography, capillary electrophoresis and capillary electrochromatography

Separation of tetracycline and its related substances: comparison of liquid chromatography, capillary electrophoresis and capillary electrochromatography

Determination of impurities in tetracycline hydrochloride by non-aqueous capillary electrophoresis

A highly selective method for quantitative determination of impurities in tetracycline antibiotics based on non-aqueous capillary electrophoresis has been developed. In tetracycline hydrochloride the degradation products 4-epitetracycline, anhydrotetracycline and 4-epianhydrotetracycline can be determined with limits of detection corresponding to 0.06%, 0.04% and 0.02% of the drug substance, respectively. The relative standard deviations were about 4% at the 0.1% level of impurity in tetracycline hydrochloride. Furthermore, it is possible to detect desmethyltetracycline as well as a number of unknown impurities within 10 min. The separation of tetracycline, oxytetracycline, doxycycline and chlortetracycline by non-aqueous capillary electrophoresis is also demonstrated. The nature of the solvents and electrolytes in the electrophoresis medium exhibit a major influence on the separation selectivity. Solvents such as methanol and acetonitrile are more volatile than water and its is demonstrated that evaporation of the solvent from sample as well as from the electrophoresis medium may cause severe problems in some capillary electrophoresis instruments.

Separation of tetracycline and its related substances by capillary zone electrophoresis

AbstractTetracycline was separated from its main impurities 4‐epitetracycline, anhydrotetracycline, 4‐epianhydrotetracycline, chlortetracycline, and demethyltetracycline by capillary electrophoresis. Systematic method development was performed in which following parameters were consecutively optimized: type and pH of the buffer, buffer concentration, type and concentration of organic modifier, voltage and temperature. Qualitative and quantitative aspects of the method are compared with liquid chromatography.

Separation of tetracycline and its degradation products by capillary zone electrophoresis

The capillary zone electrophoresis of tetracycline and its degradation products is described. Various substances, including surfactants and metal ions, were employed as additives in the running electrolyte to improve the resolution. Using disodium ethylenediaminetetraacetate as an additive in phosphate buffer solution, tetracycline and its degradation products were completely separated from each other. The baseline separation obtained completely meets the needs for determining the contents of tetracycline, 4-epitetracycline, anhydrotetracycline (ATC) and 4-epianhydrotetracycline (EATC) in tetracycline samples. Further, two unknown substances co-existing with ATC and EATC were separated that had not been mentioned or separated before. Further investigations using other techniques are needed to determine the structures of these two unknown substances. The pH dependence of the migration behaviour of tetracycline and its degradation products was also explored. The migration behaviour of zwitterionic substances is so depending on the pH of the buffer than the elution order may be changed with change in pH. The pH dependence of electroosmotic flow over the pH range 4–11 was also determined.

TLC separation of certain tetracycline and amino glycopeptide antibiotics.

The separation of tetracycline and amino glycopeptide antibiotics was achieved on silica gel thin layers. Tetracycline antibiotics were resolved on a Co+2 (1.0%) impregnated silica gel layer using ethanol:acetic acid:water (10:6:6, v/v/v) as the mobile phase. Amino glycopeptide antibiotics were separated on an untreated silica gel layer using the mobile phase n-butanol:formic acid:water (6:5:7, v/v/v). The spots of these antibiotics were located by exposing the chromatoplate to iodine vapours.

Analysis of tetracycline antibiotics and their common impurities by high-performance liquid chromatography using a polymeric column

The chromatographic separation of tetracycline, oxytetracycline, 6-demethyl-chlortetracycline, methacycline and minocycline, and the common impurities of tetracycline, oxytetracycline and chlortetracycline has been optimised on a Hamilton PRP-1 column using citrate-phosphate buffer with propan-2-ol and tetrahydrofuran as organic modifiers. Column efficiency was approximately doubled by the inclusion of 1% v/v dichloromethane in the mobile phase.

Separation and quantitative determination of tetracycline, epitetracycline, epianhydrotetracycline and anhydrotetracycline by high-performance liquid chromatography

A high-performance liquid chromatography (HPLC) separation of tetracycline and its degradation products on a C 18-reversed phase column with the mobile phase water—acetonitrile—perchloric acid in two steps with varying amounts of acetonitrile, is dascribed. Six different tetracycline preparations analyzed contain these impurities from undetectable to 7.78%. The detection limit was found to be about 5 μg/ml and the relative standard deviation of the method is between ±0.8% and 3.7%.

Separation of tetracyclines by high-speed liquid chromatography

The separation of tetracycline and its four common impurities has been studied by high-speed liquid chromatography. A preliminary study of the effectiveness of ion-exchange, adsorption, liquid—liquid partition and reversed-phase ion-pair chromatography indicated that only the last method showed promise. By developing special hydrocarbon-bonded stationary phases a rapid and complete resolution of all five tetracyclines has been obtained within 10 min. Plate heights using a derivatised 18-μm Partisil are in the range 0.15–0.3 mm. The method can be used to quantify the impurities in tetracycline at around the 1% level.