Trace determination of 10 β-lactam antibiotics in environmental and food samples by capillary liquid chromatography

Pen direct writing of SERRS-based lateral flow assays for detection of penicillin G in milk

Direct pen writing offers versatile opportunities for development of low-cost tests for point-of-care applications. In this work a lateral flow immunoassay (LFIA) test was fabricated by hand "writing" immunoprobes onto hand-cut nitrocellulose strips with a commercial fountain pen. The qualitative capabilities of the test were extended by addition of a Raman reporter and consequent design and fabrication of a Surface Enhanced Resonant Raman Scattering (SERRS)-LFIA test. As proof-of-concept, dual detection of penicillin G was achieved in milk with a visual LOD of 20 ppm and a dynamic range of 0.03-97.5 ppm. Evaluation against equivalent tests performed with conventionally prepared LFIA strips showed comparable results, thus demonstrating the validity of the test. These results demonstrate the potential for further decrease in cost and consequent broader use of LFIA tests in remote regions and resource-limited environments.

Green Multiplex Chromatographic Determination of Nine Penicillin Antibiotics Residues in Industrial Air Dust and Wastewater Environmental Samples

Determination of penicillin residues in different industrial effluents including wastewater and air samples is important to prevent exposure to residual amounts of penicillin and the development of antibiotic resistance. A green high performance liquid chromatography (HPLC) method coupled with diode array detection has been developed and validated for multiplex determination of nine penicillin antibiotics in the industrial air dust and wastewater environmental samples of penicillin facility in addition to the monitoring of facility surface cleaning. Separation was performed on C18 column with gradient elution of methanol and phosphate buffer (pH 4) at a flow rate of 1.5 mL min-1 and ultra violet (UV) detection at 220 nm. Low limits of detection were achieved (0.1-0.3 μg mL-1) indicating good sensitivity of the proposed. The method was applied for ensuring the efficiency of cleaning validation after worst-case selection. Recovery studies of the studied penicillins from fortified stainless steel and polycarbonate surfaces and swabs were between 91.91 and 100.22% with relative standard deviation 0.11-1.79%. The presence of any of the studied penicillins in wastewater samples from penicillin plant drainage was checked. Also, total air dust concentration (mg m-3) and % of penicillin active material residues in air dust were calculated from the area of the exposed group in suspension, tablet and vial production lines. The proposed method can be recommended for routine analysis of air and wastewater environmental samples for the detection of penicillin antibiotics at low levels as well as monitoring of facility surface cleaning with high accuracy and precision.

Simultaneous determination of six antibiotics belonging to four different classes in chicken meat BY HPLC/DAD and verification BY LC-MS/MS

The hypothesis of this study was to develop an extraction method allowing side-by-side extraction of six antibiotics belonging to four different classes and an HPLC/DAD method for the determination of their residues in chicken breast meat. The validation data showed that this hypothesis was achieved. The results were then confirmed by LC-MS/MS method. Sample preparation was based on the classical solid-liquid extraction with methanolic citric acid. The average recoveries were satisfactory and ranged from 75.68 to 101.3%. The linearity of the developed HPLC/DAD method was very high in the concentration range studied (R² > 0.9969). The accuracy and precision of the analytical method were between -10.8 and 12.0% relative error and 0.82 to 10.1% relative standard deviation, respectively. The LODs for five antibiotics ranged from 0.6 to 2.7 µg kg^-1 and LOQs ranged from 2.0 to 8.9 µg kg^-1. For penicillin G, the LOD was 0.16 and LOQ was 0.52 mg kg^-1.

A validated new RP-HPLC method for simultaneous determination of amoxicillin, ampicillin and cloxacillin in pharmaceutical formulations

As per the World Health Organization, 10% of medicines in low- and middle-income nations are of poor quality and pose a huge public health risk. The development and implementation of cost-effective, efficient and quick analytical methods to control the quality of these medicines is one of the immediate strategies to avoid such a situation. Hence, the main goal of this study was to develop and validate a simple, specific and precise new RP–HPLC method for simultaneous analysis of amoxicillin, ampicillin and cloxacillin in pharmaceutical formulations. The chromatographic analysis was achieved using Shodex C18 (250 × 4.6 mm, 5 μm) column with UV detection at 225 nm. The mobile phase was a gradient mixture of 30 mM phosphate buffer, pH 4.0 (mobile phase A) and acetonitrile (mobile phase B). Efficient separation of the three drugs was obtained using the final optimized chromatographic conditions. The developed method was validated for its specificity, linearity, precision, accuracy and robustness as per the ICH guidelines. The validation results showed that the method was specific, linear, precise, accurate and robust for the simultaneous determination of the three drugs. The developed method was applied to determine the content of the three drugs in pharmaceutical formulations. The assay results of the preparations showed that their drug content was within the pharmacopeial limit stipulated for each drug product. It can be concluded that the proposed method is suitable for simultaneous determination of amoxicillin, ampicillin and cloxacillin in pharmaceutical formulations in industries and regulatory laboratories.

Selective and fast removal and determination of β-lactam antibiotics in aqueous solution using multiple templates imprinted polymers based on magnetic hybrid carbon material

Selective and fast adsorption of five broad-spectrum β-lactam antibiotics included amoxicillin, cephalexin, cefazolin, penicillin G and oxacillin was achieved by novel surface molecular imprinting polymers (MIPs) with magnetic hybrid carbon material as the substrate. The characteristics of MIPs were studied by scanning electron microscope, Fourier transform infrared spectrometer, thermogravimetric analysis, etc. And through a series of adsorption experiments to examine the kinetics, isotherms, thermodynamics, selectivity and reusability for sorption of β-lactam antibiotics onto the MIPs. The adsorption equilibriums were accomplished in about 60 min with adsorption capacities of 4.57-24.55 mg g^-1, while the adsorption process was preferably fitted with pseudo-second-order kinetic model and Freundlich model. The imprinting factors ranged from 1.88 to 9.94 indicated the MIPs possessed excellent recognition ability, and its good reusability was demonstrated after five times adsorption-desorption cycles without a large drop in adsorption capacity. Furthermore, a new detection method was developed by combining of MIPs with solid phase extraction and high performance liquid chromatography (MIPs-SPE-HPLC). Under the optimal SPE conditions, the limits of detection (LODs) for the five BLAs were 0.24-0.56 µg L^-1, with RSDs of 0.76-5.39%. The synthesized MIPs and the proposed MIPs-SPE-HPLC method can be applied for the efficient, simultaneous separation and detection of BLAs.

A sensitive and high-throughput quantitative liquid chromatography high-resolution mass spectrometry method for therapeutic drug monitoring of 10 β-lactam antibiotics, linezolid and two β-lactamase inhibitors in human plasma

An ultra-high pressure liquid chromatography high-resolution mass spectrometric (UHPLC-HRMS) method was developed for the simultaneous and sensitive quantification of 10 β-lactam antibiotics (cefepime, meropenem, amoxicillin, cefazolin, benzylpenicillin, ceftazidime, piperacillin, flucloxacillin, cefuroxime and aztreonam), linezolid and β-lactamase inhibitors tazobactam and clavulanic acid in human plasma. Validation according to the EMA guidelines showed excellent within- and between-run accuracy and precision (i.e. between 1.1 and 8.5%) and high sensitivity (i.e. lower limit of quantification between 0.25 and 1 mg/L). The UHPLC-HRMS method enables a short turnaround time and high sensitivity and needs only a small amount of plasma, allowing appropriate routine therapeutic drug monitoring. The short turnaround time is obtained by speeding up the protocol on multiple levels, i.e. fast and workload-efficient sample preparation (i.e. protein precipitation and dilution), short (4 min) instrument run time, simultaneous measurement of all relevant β-lactam antibiotics used in the intensive care unit and the use of the same instrument, column and mobile phases as for the other routine methods in our laboratory.

A novel label-free photoelectrochemical aptasensor for the sensitive detection of ampicillin based on carbon-coated Bi2S3 nanorods

The prepared Bi2S3@C nanorods with remarkable photoelectrochemical properties served as a PEC sensor platform for the ultrasensitive analysis of ampicillin.

Miniaturized liquid chromatography applied to the analysis of residues and contaminants in food: A review

The humankind is pretty dependent on food to control several biological processes into the organism. As the world population increases, the demand for foodstuffs follows the same trend claiming for a high food production situation. For this reason, a substantial amount of chemicals is used in agriculture and livestock husbandries every year, enhancing the likelihood of contaminated foodstuffs being commercialized. This outlook becomes a public health concern; thus, the governmental regulatory agencies impose laws to control the residues and contaminants in food matrices. Currently, one of the most important analytical techniques to perform it is LC. Despite its already recognized effectiveness, it is often time consuming and requires significant volumes of reagents, which are transformed into toxic waste. In this context, miniaturized LC modes emerge as a greener and more effective analytical technique. They have remarkable advantages, including higher sensitivity, lower sample amount, solvent and stationary phase requirements, and more natural coupling to MS. In this review, most of the critical characteristics of them are discussed, focusing on the benchtop instruments and their related analytical columns. Additionally, a discussion regarding the last 10 years of publications reporting miniaturized LC application for the analysis of natural and industrial food samples is categorized. The main chemical classes as applied in the crops are highlighted, including pesticides, veterinary drugs, and mycotoxins.

Graphene Oxide-Based Dispersive-Solid Phase Extraction for Preconcentration and Determination of Ampicillin Sodium and Clindamycin Hydrochloride Antibiotics in Environmental Water Samples Followed by HPLC-UV Detection

In this work, a reusable graphene oxide (GO) based dispersive-solid phase extraction (d-SPE) was synthesized and used for the analysis of trace ampicillin sodium (AMP) and clindamycin hydrochloride (CLI) in water samples followed by high performance liquid chromatography-UV detection (HPLC-UV). Batch experiments were conducted to investigate the effects of pH and volume of the sample solution, contact time, adsorption isotherms, temperature, and desorption conditions. The maximum adsorption capacities of AMP and CLI on GO nanosheets were found to be 33.33 mg g^-1 and 47 mg g^-1, respectively. The adsorption isotherm data can be well fitted by Temkin (AMP and CLI) and Freundlich (AMP), and the adsorption process followed the pseudo-second-order model. The thermodynamic parameters were calculated, indicated that the adsorption process of both analytes were spontaneous and exothermic. In addition, the d-SPE following HPLC analyses showed good linearity in the range of 0.5-200 ng mL^-1 (R²= 0.999) for AMP and 1-200 ng mL^-1 (R²= 0.999) for CLI, with LOD of 0.04 and 0.24 ng mL^-1 for AMP and CLI, respectively. The percent of extraction recoveries, intra and inter-day precisions (expressed as RSD %, n = 3) were in the range of 96.4-101.6%, 2.2-3.0, and 3.7-4.7 for AMP as well as 94.2-98.6%, 2.2-3.8, and 3.5-4.6 for CLI, respectively. The preconcentration factor of 20 was achieved for both analytes. From these results, it can be concluded that the validated method is a simple, cost-effective and repeatable method for analysis of AMP and CLI in water samples and provide a new platform for antibiotics decontamination.

Investigation of the Persistence of Penicillin G and Dihydrostreptomycin Residues in Milk of Lactating Buffaloes ( Bubalus bubalis) Using Ultra-High-Performance Liquid Chromatography and Tandem Mass Spectrometry

The purpose of this research was to evaluate the persistence of penicillin G and dihydrostreptomycin in milk of lactating buffaloes following intramuscular injection of procaine penicillin G (200000 IU/mL) and dihydrostreptomycin sulfate (250 mg/mL) every 24 h for 3 days. Milk samples were collected twice daily up to the 13th milking post-treatment and analyzed by ultra-high-performance liquid chromatography coupled to tandem mass spectrometry. The analytical method has been validated according to Commission Decision 2002/657/EC. The highest concentrations of penicillin G (275 μg kg^-1) and dihydrostreptomycin (220.5 μg kg^-1) were detected in the milk of the first milkings post-treatment, and levels were below the maximum residue limit of 4 and 200 μg kg^-1 in all treated buffaloes at milkings 12 and 2, respectively. The results of this study demonstrate that a nine-milking withdrawal time set for bovine milk was not adequate for depletion of penicillin G in lactating buffaloes.

Residues of 2-hydroxy-3-phenylpyrazine, a degradation product of some β-lactam antibiotics, in environmental water in Vietnam

Antibiotic-resistant bacteria have become a serious problem worldwide, caused in part by the excessive use and discharge of antibiotics into the environment. Ampicillin (ABPC) is a widely used antibiotic. However, this chemical rapidly decomposes in water containing divalent cations like Ca²⁺ and Mg²⁺, thus, detection of ABPC in environmental water is difficult. This study was carried out to evaluate the presence of 2-hydroxy-3-phenylpyrazine (HPP), one of the degradation products of ABPC and β-lactam antibiotics with an ABPC substructure, in environmental water. An analytical method for HPP monitoring in environmental water was developed using liquid chromatography/tandem mass spectrometry. The analyte was extracted from water samples and enriched using a solid-phase extraction cartridge. The quantification limit was 1 ng L^-1. The HPP recovery rates from spiked water samples of 25 and 125 ng L^-1 were 84.1 and 86.1%, respectively. The method was then used to determine HPP residue levels in 98 environmental water samples from rivers, household ponds, and aquacultural ponds in Vietnam. HPP residues were detected in 60 samples. The HPP detection rates in rivers and household ponds were 42 and 79%, respectively. HPP was not detected in aquacultural ponds. HPP residue concentrations in the samples ranged from 1.3 to 413.3 ng L^-1. The residue levels in rivers flowing through city centres were higher than levels in other sampling locations. The findings of this study suggest that HPP is a promising marker for assessing the discharge of ABPC and β-lactam antibiotics with an ABPC substructure into the environment around sampling sites.

Selection of DNA aptamers against penicillin G using Capture-SELEX for the development of an impedimetric sensor

This paper describes for the first time the selection of aptamers selective to penicillin. Aptamers were selected using a specific process called Capture-SELEX (Systematic Evolution of Ligands by Exponential Enrichment). This technique is based on the selection of DNA aptamers using penicillin G in solution while the ssDNA library is fixed on a support. One aptamer showing a good affinity to penicillin was finally selected and tested in electrochemical sensor configuration, using electrochemical impedance spectroscopy as detection technique. The developed aptasensor allowed the detection of penicillin in a wide concentration range, comprised between 0.4 and 1000µgL^-1 Such performance was compatible with milk analysis, as the maximum residue limit tolerated in this matrix is 4µgL^-1. The selectivity of the developed sensor was also studied, showing that the sensor was also able to bind other beta-lactam antibiotics, although with a weaker affinity. Finally the sensor was used for detection of penicillin G in milk. It was shown that a simple sample treatment with isopropanol followed by filtration was sufficient to eliminate matrix effects, allowing the determination of penicillin in milk at concentrations compatible with legislation requirements.

Simultaneous determination of amoxicillin and clavulanic acid in pharmaceutical preparations by capillary zone electrophoresis

ABSTRACT Clavulanic acid enhances the antibacterial spectrum of amoxicillin by rendering most β-lactamase producing isolates susceptible to the drug. A fast, simple and efficient capillary electrophoresis method was developed for the simultaneous determination of amoxicillin and clavulanic acid from complex mixtures. Using a 25 mM sodium tetraborate as background electrolyte at a pH of 9.30, + 25 kV applied voltage, 25 °C system temperature, UV determination at 230 nm; we succeeded in simultaneous separation of amoxicillin and clavulanic acid in approximately 2 minutes. The analytical performance of the method was evaluated in terms of reproducibility, precision, accuracy, and linearity. The optimized analytical method was applied for the determination of the two analytes from combined commercial pharmaceutical preparations. This CE method is fast, inexpensive, efficient, and environmentally friendly when compared with the more frequently used high performance liquid chromatography methods described in the literature.

Development of an optimized HPLC method for the simultaneous determination of six compounds containing β-lactam ring in human plasma and urine using experimental design methodology

β-Lactam antibiotics are commonly prescribed with β-lactamase inhibitors to patients, for that it is necessary to develop an optimized chromatographic method which determine them simultaneously in biological fluids.

A novel fluorescence polarization assay for determination of penicillin G in milk

Detection of penicillin G in milk is of interest because of the wide use of this antibiotic in livestock. Current analytical methods used to quantify the penicillin G in milk are based on HPLC, mass spectrometry and electrophoresis. These methodologies are time-consuming and require trained personnel. In addition, it is not easy to envisage the development of a portable device for in situ analyses based on these methods. We present a novel sensing approach for detecting the presence of penicillin G in milk. The proposed method is based penicillin G conjugate labeled with red-emitting dye with properly produced anti-penicillin G antibodies. The results obtained suggest our method could be applied directly in milk without interference from other substances. The limit of detection of the method was 1.0 nmol/L, which is much less than the required MRL in EU regulations (12.0 nmol/L).

Piezoelectric immunosensors for the detection of individual antibiotics and the total content of penicillin antibiotics in foodstuffs

Piezoelectric immunosensors on the basis of homologous and group-specificantibodies have been developed for detecting penicillin G, ampicillin, and the total content of penicillin antibiotics. The receptor coating of the sensor was obtained by the immobilization of penicillin G or ampicillin hapten-protein conjugates on the polypyrrole film obtained by electropolymerization and activated by glutaraldehyde. The affinity constants and the cross reactivity coefficients have been calculated. This made it possible to estimate the affinity and specificity of the polyclonal and monoclonal antibodies used. The calibration curves are linear in the range of concentrations 2.5-250.0 ng ml(-1) (penicillin G), 2.5-500.0 ng ml(-1) (ampicillin), and 1-500 ng ml(-1) (group of penicillin). The limits of detection are 0.8 ng ml(-1), 3.9 ng ml(-1), which are lower than MRL, established for penicillin antibiotics. The sensors were tested in detecting penicillins in milk, pork, beef, liver.

LC/UV determination of cefradine, cefuroxime, and cefotaxime in dairy milk, human serum and wastewater samples

Cephalosporins type antibiotics are widely used to treat infectious diseases. Their determination is not only important in blood/serum of patients under treatment but also in diverse matrices like wastewaters, milk etc. as contaminant. Keeping in view the need, a new high performance liquid chromatographic method for the determination of three cephalosporins (cefradine, cefuroxime and cefotaxime) has been developed. Separation was performed on an ODS column with binary solvent elution of aqueous formic acid (0.05%) and methanol in the ratio of 45: 55 (v/v) at a flow rate of 1 mL min^-1 and UV detection at 260 nm. Under optimised conditions, all three cephalosporins were baseline separated within 5 min. Linear responses for cefradine 5–20 μg mL^-1, cefuroxime 0.5-15 μg mL^-1 and cefotaxime 1.0-20 μg mL^-1 were established. LOD of 0.05-0.25 μg mL^-1 after preconcentration was achieved. The method was applied to serum samples of patients under treatment with these antibiotics and to screen the selected cephalosporins from hospital wastewater and milk samples. Moreover, method was applied to study stability of aqueous solutions and acid/base induced degradation of all three drugs.

Origin and evolution of antibiotic resistance: the common mechanisms of emergence and spread in water bodies

The environment, and especially freshwater, constitutes a reactor where the evolution and the rise of new resistances occur. In water bodies such as waste water effluents, lakes, and rivers or streams, bacteria from different sources, e.g., urban, industrial, and agricultural waste, probably selected by intensive antibiotic usage, are collected and mixed with environmental species. This may cause two effects on the development of antibiotic resistances: first, the contamination of water by antibiotics or other pollutants lead to the rise of resistances due to selection processes, for instance, of strains over-expressing broad range defensive mechanisms, such as efflux pumps. Second, since environmental species are provided with intrinsic antibiotic resistance mechanisms, the mixture with allochthonous species is likely to cause genetic exchange. In this context, the role of phages and integrons for the spread of resistance mechanisms appears significant. Allochthonous species could acquire new resistances from environmental donors and introduce the newly acquired resistance mechanisms into the clinics. This is illustrated by clinically relevant resistance mechanisms, such as the fluoroquinolones resistance genes qnr. Freshwater appears to play an important role in the emergence and in the spread of antibiotic resistances, highlighting the necessity for strategies of water quality improvement. We assume that further knowledge is needed to better understand the role of the environment as reservoir of antibiotic resistances and to elucidate the link between environmental pollution by anthropogenic pressures and emergence of antibiotic resistances. Only an integrated vision of these two aspects can provide elements to assess the risk of spread of antibiotic resistances via water bodies and suggest, in this context, solutions for this urgent health issue.

Simultaneous determination of 12 beta-lactam antibiotics in human plasma by high-performance liquid chromatography with UV detection: application to therapeutic drug monitoring

A rapid and specific high-performance liquid chromatography method with UV detection (HPLC-UV) for the simultaneous determination of 12 beta-lactam antibiotics (amoxicillin, cefepime, cefotaxime, ceftazidime, ceftriaxone, cloxacillin, imipenem, meropenem, oxacillin, penicillin G, piperacillin, and ticarcillin) in small samples of human plasma is described. Extraction consisted of protein precipitation by acetonitrile. An Atlantis T3 analytical column with a linear gradient of acetonitrile and a pH 2 phosphoric acid solution was used for separation. Wavelength photodiode array detection was set either at 210 nm, 230 nm, or 298 nm according to the compound. This method is accurate and reproducible (coefficient of variation [CV] < 8%), allowing quantification of beta-lactam plasma levels from 5 to 250 μg/ml without interference with other common drugs. This technique is easy to use in routine therapeutic drug monitoring of beta-lactam antibiotics.

Application of a liquid chromatographic procedure for the analysis of penicillin antibiotics in biological fluids and pharmaceutical formulations using sodium dodecyl sulphate/propanol mobile phases and direct injection

A direct injection liquid chromatography procedure was developed for the simultaneous determination of four penicillin antibiotics (amoxicillin, ampicillin, cloxacillin and dicloxacillin) in pharmaceutical formulations and physiological fluids (urine) using hybrid micellar mobile phases. These antimicrobials are used to treat gastrointestinal and systemic infections. The four penicillins were analysed using a Zorbax C18 reversed-phase column and detected at 210 nm. These antibiotics were separated by an interpretive optimisation procedure based on the accurate description of the retention and shape of the chromatographic peaks. Antibiotics were eluted in less than 16 min with no interference by the urine protein band or endogenous compounds using the mobile phase 0.11 M sodium dodecyl sulphate-6% propanol-0.01 M NaH(2)PO(4) buffered at pH 3. The method was validated according to the Food and Drug Administration guideline, including analytical parameters such as linearity (R(2)>0.993), intra- and inter-day precisions (RSD, %: 0.1-4.4 and 1.2-5.9, respectively), and robustness for the four compounds. This method is sensitive enough for the routine analysis of penicillins at therapeutic urine levels, with limits of detection in the 1.5-15 ng mL(-1) range and limits of quantification of 50 ng mL(-1). Recoveries in a micellar medium and a spiked urine matrix were in the 92.4-108.2% and 96-110% ranges, respectively. Finally, the method was successfully applied to determine these antibiotics in urine samples and pharmaceutical formulations.