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The minimum set of parameters that can be used to assess the adsorption capacity of activated carbon (AC) produced from termite bio-waste was determined. Three types of AC were prepared: AC600 at 600 °C, MAC600 at the same temperature and impregnated with FeCl3, and AC800 at 800 °C. The influence of the solution pH on the adsorption, adsorption kinetics, isotherms and thermodynamic parameters was considered to characterize the amoxicillin (AMX) adsorption process. The AC materials had surface areas (m2 g-1) of approximately 248.8 for AC600, 501.6 for AC800 and 269.5 for MAC600, with point of zero charge (pHPZC) values of 8.3, 7.5 and 1.7, respectively. A time period of 30 min was chosen for the adsorption kinetics, which was best represented by the pseudo-first-order model for AC600, the intraparticle diffusion model for AC800 and the pseudo-second-order model for MAC600. Regarding the isotherms, a maximum adsorption of 23.4 mg g-1 was found for AC800. In general, the thermodynamic parameters demonstrated a non-spontaneous process. It seems that the medium conditions, the adsorbate and adsorbent characteristics, and the Gibbs free energy are the most important parameters to be considered in a preliminary assessment of the adsorption efficiency of specific adsorbent/adsorbate pairs.

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Antibiotics are widely used in human medicine and veterinary production. Residues of these compounds reach the water sources through waste or direct application (e.g. aquaculture). The constant input of the parent drugs and their transformation products into the environment leads these pharmaceuticals to be considered as emerging pollutants. For some molecules, the pathway of degradation and formation in products is less known. To assess the impact of these substances in the environment and in the human health, it is necessary to elucidate the transformation products and their kinetic of degradation to evaluate the possible risks. In the present report, the characterization and the degradation kinetic of two widely used ß-lactams antibiotics - amoxicillin and ampicillin - was evaluated. Surface water samples containing these antibiotics were submitted to photolysis and analyzed by liquid chromatography coupled to mass spectrometry with Orbitrap detection in order to establish the profile of degradation and the formation of transformation products. Results showed that the degradation of amoxicillin and ampicillin is almost complete and reach their maximum at 48 h in river water. Moreover, a database containing >65 transformation products of amoxicillin and ampicillin was build and real samples of industrial wastewater were analyzed to investigate the occurrence of amoxicillin, ampicillin and their transformation products.

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Amoxicillin is a useful antibiotic to combat bacterial infections. However, this drug can cause serious problems when discarded in waterways due to its great bioaccumulation potential. This compound can be treated via advanced oxidation processes (AOPs), which are capable of converting amoxicillin into carbon dioxide and water. In this context, the use of ozone as an oxidizer has excelled in amoxicillin degradation. This paper aims at treating a synthetic solution of amoxicillin (0.1 g L-1) in a reactor with ozone bubbling. A Design of Experiment (DoE) with a response surface known as Central Composite Design (CCD) was used to optimize the treatment process. In addition, a Normal Boundary Intersection (NBI) method was used in the construction of a Pareto boundary chart. Results after 1-h treatment showed a reduction of 53% of the initial organic matter from a designed model using factors, such as pH, ozone generator power, and O3 flow. A model was built from the CCD with score of 0.9929. Thus, the model was able to represent the real scenario with confidence.

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We report a new fast method for the simultaneous determination of amoxicillin, clavulanate, and potassium by capillary electrophoresis with capacitively coupled contactless conductivity detection. Samples containing potassium as the cation, and both amoxicillin and clavulanate as anions were determined simultaneously in a single run (in less than 45 s) using 10 mmol/L of both 2-amino-2-hydroxymethyl-propane-1,3-diol and 3-{[2-hydroxy-1,1-bis(hydroxymethyl)ethyl]amino}-1-propanesulfonic acid (pH 8.4) as the background electrolyte. Limits of detection were 25.0, 5.0, and 4.0 µmol/L for amoxicillin, clavulanate, and potassium, respectively. The proposed method is inexpensive, simple, fast (75 injections h-1 ), environment friendly (minimal waste generation), and accurate (recovery values between 98 and 103%). The results obtained with the proposed method were statistically similar (95% confidence level) to those obtained by using high-performance liquid chromatography (amoxicillin and clavulanate) and flame photometry (potassium).

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The aim of this study was to prepare molecularly imprinted polymers (MIPs) with ampicillin (AMP) and to evaluate the feasibility of these materials for being used as solid phase extraction sorbent for the selective preconcentration and determination of AMP in cow milk samples. MIPs were synthesized by bulk polymerization using methacrylic acid or methyl methacrylate as monomer and ethylene glycol dimethacrylate as cross-linker at different ratios. Characterization of the MIPs were carried out by Fourier-transform infrared spectrometry. The variables affecting the molecularly imprinted solid-phase extraction (MISPE) procedure were optimized. AMP recoveries were higher than 98%, and RSD less than 7%. A preconcentration factor of 20 was reached, which was sufficient to determine AMP at levels allowed by the EU (4µgkg-1) in cow milk. The selectivity of the AMP-MIP was evaluated in presence of other structurally related ß-lactam antibiotics (amoxicillin, oxacillin, penicillin G).

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Bacterial infections are the second leading cause of global mortality. Considering this fact, it is extremely important studying the antimicrobial agents. Amoxicillin is an antimicrobial agent that belongs to the class of penicillins; it has bactericidal activity and is widely used in the Brazilian health system. In literature, some analytical methods are found for the identification and quantification of this penicillin, which are essential for its quality control, which ensures maintaining the product characteristics, therapeutic efficacy and patient's safety. Thus, this study presents a brief literature review on amoxicillin and the analytical methods developed for the analysis of this drug in official and scientific papers. The major analytical methods found were high-performance liquid chromatography (HPLC), ultra-performance liquid chromatography (U-HPLC), capillary electrophoresis and iodometry and diffuse reflectance infrared Fourier transform. It is essential to note that most of the developed methods used toxic and hazardous solvents, which makes necessary industries and researchers choose to develop environmental-friendly techniques to provide enhanced benefits to environment and staff.

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Amoxicillin is a synthetic penicillin used in the hospital, residential and veterinary surroundings. The indiscriminate use of such medication may cause social and environmental damages. This study aims at determining the amoxicillin contents in water of two rivers located in State of Bahia, the Água Fria and Verruga rivers. An analytical method was developed, optimized and validated for determining the amoxicillin residue, by using the high performance liquid chromatography coupled with UV-Visible detector (HPLC-UV). The study was performed according to the chromatographic parameters validation. Considering that the maximum acceptable values of amoxicillin for drinking water were nonexistent, the found results might be considered as an indicator of contamination by this substance. The occurrence of this antibiotic in the two rivers analyzed in this study indicated a heavy contamination in the urban areas where the increased surface water runoffs occur; and their concentrations were higher than 11 mg.L-1. The validation parameters indicated that the method showed the capacity for detecting low values of quantification limits (2.7 mg.L-1) and of detection (0.7 mg.L-1), good precision (DSR 7 %) and accuracy (96.75 %), thus it turned to be an important tool for assessing amoxicillin contents.(AU)

A amoxicilina é penicilina sintética de uso em ambiente hospitalar, residencial e veterinário. O uso indiscriminado deste medicamento pode acarretar prejuízos sociais e ambientais. O presente trabalho determinou os níveis de amoxicilina em dois rios localizados no sudoeste do estado da Bahia, rios Água Fria e Verruga. Uma metodologia analítica foi desenvolvida, otimizada e validada para efetuar a determinação de resíduos de amoxicilina, empregando-se a cromatografia líquida de alta eficiência acoplada ao detector UV-visível (CLAE-UV). A avaliação do mérito do método foi baseada nos parâmetros cromatográficos de validação: linearidade, limites de detecção e quantificação, precisão, exatidão e seletividade. Devido à inexistência de valores máximos de amoxicilina aceitáveis para a água de consumo, os resultados obtidos podem constituir um indicativo dos níveis de contaminação dos recursos hídricos por este medicamento. As maiores concentrações, superiores a 11 mg.L-1 deste antibiótico, foram detectadas nas zonas onde recebem aportes dos deflúvios urbanos. Os parâmetros de validação demonstraram que o método apresentou capacidade de detecção de baixos valores dos limites de quantificação (2,7 mg.L-1) e de detecção (0,7 mg.L-1), boa precisão (DPR 7 %) e exatidão (96,75 %), constituindo-se em uma importante ferramenta na avaliação de teores de amoxicilina.(AU)

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O objetivo foi avaliar a eficácia da amoxicilina em diferentes periodos (3 e 7 dias) no tratamento coadjuvante de abscessos dentoalveolares após realização de drenagem. Foram avaliados 20 voluntários divididos em 2 grupos (n=10): G1 - 19 de amoxicilina, antes do procedimento de drenagem e 500mg de 8/8h por 3 dias; G2 - 1 9 de amoxicilina antes do procedimento e 500mg de 8/8h por 7 dias. Foram avaliados o edema, dor, febre, supuração e trismo, e os voluntários tiveram acompanhamento clínico diário. O edema foi avaliado em duas medidas (Tragus a Asa do Nariz e Tragus a Comissura Labial). A abertura bucal e o edema foram avaliados antes da drenagem, 1, 2, 3 e 7 dias após. Para a avaliação de dor foi utilizada a escala analógica visual (EAV) antes e nos intervalos O, 1 h, 2h, 4h, 12h, 1 dia, 2 dias, 3 dias e 1 semana após. Os resultados fora m su bmetidos à a ná I ise estatística (Kruska II-Wa II is), com n ivel de sig n ificâ ncia de 5%. Quanto aos parâmetros clínicos avaliados, não foram observadas diferenças estatisticamente significantes entre os grupos [p>0,05), e nenhum dos voluntários apresentou complicações no período do pós-atendimento. Concluiu-se que, após a intervenção clínica, a eficácia da amoxicilina nos períodos avaliados foi similar na amostra avaliada

The aim of this study was to compare the use of amoxicillin for different time intervals (3 and 7 days) for treatment of acute dentoalveolar abscesses after performing drainage. Twenty volunteers were divided into two groups (n = 10): G 1 - The volunteers received 1 9 of amoxicillin before the drainage procedure, and 500mg of amoxicillin every 8 hours for 3 days; G2 - The volunteers received 19 of amoxicillin before the drainage procedure, and 500mg of amoxicillin every 8 hours for 7 days. For each patient followed-up, acute infectious conditions were investigated, and pain, edema, fever, suppuration and trismus were evaluated. To evaluate pain was used a visual analog scale [VAS) in the intervals O, 1 h, 2h , 4h , 12 h , 1,2 and 3 days and 1 week after the drainage. The results were submmited to statistical analysis [Kruskal - Wallisl. with a significance levei of 5 %. There was no statistically significant difference between the groups considering the parameters evaluated [p>0.05). None of the volunteers had complications in the post clinical care assessed. It was concluded that after clinical intervention, the effectiveness of the use of amoxicillin in periods of 3 and 7 days was similar in the evaluated volunteers

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This paper proposes a new method for determination of amoxicillin in pharmaceutical suspension formulations, based on transflectance near infrared (NIR) measurements and partial least squares (PLS) multivariate calibration. A complete methodology was implemented for developing the proposed method, including an experimental design, data preprocessing by using multiple scatter correction (MSC) and outlier detection based on high values of leverage, and X and Y residuals. The best PLS model was obtained with seven latent variables in the range from 40.0 to 65.0 mg mL(-1) of amoxicillin, providing a root mean square error of prediction (RMSEP) of 1.6 mg mL(-1). The method was validated in accordance with Brazilian and international guidelines, through the estimate of figures of merit, such as linearity, precision, accuracy, robustness, selectivity, analytical sensitivity, limits of detection and quantitation, and bias. The results for determinations in four commercial pharmaceutical formulations were in agreement with the official high performance liquid chromatographic (HPLC) method at the 99% confidence level. A pseudo-univariate calibration curve was also obtained based on the net analyte signal (NAS). The proposed chemometric method presented the advantages of rapidity, simplicity, low cost, and no use of solvents, compared to the principal alternative methods based on HPLC.

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A new method for the simultaneous determination of amoxicillin trihydrate (AMT) and sodium diclofenac (DIC) in pharmaceutical formulations is proposed. The resolution of binary mixtures of these drugs has been accomplished by using partial least squares (PLS) regression analysis. The model was obtained from UV spectral data and validated by internal cross-validation; it was used to find the concentration of analytes in some commercial samples. The method was applied in the concentration ranges of 0-120.0 mg L(-1) for AMT and 0-16.0 mg L(-1) for DIC, allowing a rapid, accurate and precise simultaneous estimation of the concentration of both analytes of interest in the presence of small amounts of different, unmodelled, absorbing excipients, in spite of their important spectral overlapping. The accuracy, precision and figures of merit (FOM) for AMT and DIC were calculated. This new method proved to be useful for a fast and simultaneous determination of AMT and DIC in pharmaceutical formulations.

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