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Yulin Ren - One of the best experts on this subject based on the ideXlab platform.
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radial basis function networks combined with genetic algorithm applied to nondestructive determination of compound Erythromycin Ethylsuccinate powder
Chemometrics and Intelligent Laboratory Systems, 2008Co-Authors: Lihua Wang, Ying Dou, Mingchao Zhu, Yulin RenAbstract:A new assay method for the nondestructive determination of pharmaceutical samples with different concentrations on the basis of the near-infrared (NIR) spectral data is presented in this paper. By the proposed method, powerful radial basis function (RBF) networks can be produced based on a genetic algorithm (GA), which is applied for auto-configuring the structure of the networks and obtaining the optimal network parameters. The Akaike's information criterion (AIC) is used to evaluate the fitness of individual networks. Therefore, the genetic algorithm-radial basis function (GA-RBF) networks have a better generalization performance and simpler network structure. Four different GA-RBF network models based on pretreated spectra (multiplicative scatter correction MSC, standard normal variate SNV, first-derivative and second-derivative spectra) have been established and compared. The obtained GA-RBF networks can give robust and satisfactory prediction and the optimal GA-RBF networks after the SNV treatment is found to provide the best results. It is demonstrated that the proposed GA-RBF method based on NIR spectral data is a valuable tool for quantitative analysis.
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nondestructive quantitative analysis of Erythromycin Ethylsuccinate powder drug via short wave near infrared spectroscopy combined with radial basis function neural networks
European Journal of Pharmaceutical Sciences, 2007Co-Authors: Ying Dou, Ye Guo, Yulin RenAbstract:A new assay method for the nondestructive determination of Erythromycin Ethylsuccinate powder drug via short-wave near-infrared spectroscopy (NIR) combined with radial basis function (RBF) neural networks is investigated. The modern near-infrared spectroscopy analysis technique is efficient, simple and nondestructive, which has been used in chemical analysis in diverse fields. Short-wave NIR is a more rapid, flexible, and cost-effective method to control product concentration in pharmaceutical industry. The RBF neural networks are local approximation networks that have superiorities in function approximation and learning speed. In addition, the structure of RBF networks is simple. Estimate and calibration of the sample concentration via short-wave NIR are made with the aid of RBF models based on conventional spectra, standard normal variate (SNV), multiplicative scatter correction (MSC) and the first-derivative spectra. Various optimum models of them are established and compared. Experiment results show that the models of SNV spectra can give better performance, and the optimized RBF neural network model after SNV treatment were given, by which the root-mean-square-errors (RMSE) for calibration set and test set were 0.3266% and 0.5244%, respectively and the correlation coefficients (R) for calibration set and test set were 0.9942 and 0.9852, respectively. The proposed RBF method based on short-wave NIR is more valuable and economical for quantitative analysis than traditional methods such as partial least squares (PLS).
Andrzej Bobrowski - One of the best experts on this subject based on the ideXlab platform.
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voltammetric behavior of Erythromycin Ethylsuccinate at a renewable silver amalgam film electrode and its determination in urine and in a pharmaceutical preparation
Electrochimica Acta, 2016Co-Authors: Olga Vajdle, Valeria Guzsvany, Dusan Skoric, Jasmina Anojcic, Pavle Jovanov, Milka Avramovivic, Janos Csanadi, Zoltan Konya, Slobodan Petrovic, Andrzej BobrowskiAbstract:Abstract Erythromycin, a macrolide antibiotic, has similar antimicrobial spectrum to penicillin and it is widely used, especially in the treatment of patients who are allergic to penicillin. In this work, the application of a renewable silver-amalgam film electrode (Hg(Ag)FE) for the characterization and determination of Erythromycin Ethylsuccinate (EES), a widely used esterified form of this antibiotic, by means of cyclic voltammetry (CV) and square wave voltammetry (SWV) is presented. In the aqueous Britton-Robinson buffer (pH 5.0–9.0) that served as the supporting electrolyte, one reduction peak of EES was observed in the investigated potential range between −0.75 V and −1.80 V vs SCE, with peak potential maxima ranging from −1.59 V to −1.70 V, which strongly depended on the applied pH, as did the peak shape. For the analytical purposes the pH of 7.0 was selected, since in this electrolyte the EES peak was well-shaped and separated from the background current of the supporting electrolyte in both cases; in the direct cathodic SWV and in the case of square wave adsorptive stripping voltammetry (SW-AdSV). It was established, by the E p -pH correlation, that protons strongly influenced the electrochemical reduction of EES. The CVs recorded between 0.025–0.50 V s −1 at pH 7.0 confirmed that the electrode reaction is adsorption-controlled. Based on the series of 1 H NMR measurements it is proved that the tertiary amino group of EES is mainly in its protonated form at pH 7.0 which may lead, at appropriate accumulation potential and time, to the favored adsorption of the target ionic form of the analyte improving on such way the sensitivity of the SW-AdSV method. The optimized procedures resulted in stable SWV responses with good linear correlation in the EES concentration range from 4.53 to 29.8 μg mL −1 (LOD = 1.36 μg mL −1 ), and from 0.69 μg mL −1 to 2.44 μg mL −1 (LOD 0.21 μg mL −1 ) in the case of optimized SW-AdSV. The relative standard deviation is below 1.5%. The reliability of the elaborated procedures and thus the accuracy of the obtained results were validated by comparing them with those obtained by means of HPLC-DAD measurements. The direct cathodic SWV method was successfully applied for the determination of EES in the pharmaceutical preparation Eritromicin ® , while SW-AdSV was applied in the case of the spiked urine sample. In both cases, the standard addition method was used.
B Rouveix - One of the best experts on this subject based on the ideXlab platform.
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effect of a single oral dose of two Erythromycin Ethylsuccinate formulations on gastric emptying in healthy volunteers a scintigraphic study
Fundamental & Clinical Pharmacology, 1998Co-Authors: F Delatour, Le D Guludec, F Caron, Francois Faurisson, J C Torlotin, B RouveixAbstract:Macrolides are potential gastrokinetic agents. The purpose of this study was to assess the effect of a single oral dose of two Erythromycin formulations on gastric emptying of the solid and liquid phases in twelve healthy volunteers and to seek a correlation between pharmacokinetic parameters and changes in gastric emptying. The gastric emptying times of liquids and solids were measured simultaneously by means of a scintigraphic technique after a single oral administration of amorphous Erythromycin Ethylsuccinate (500 mg), crystalline Erythromycin Ethylsuccinate (1000 mg) or a placebo, in a double-blind crossover study in three separate weeks. Blood samples were obtained for Erythromycin assay. The two oral formulations induced a similar acceleration of gastric emptying. When compared to the placebo, both Erythromycin preparations significantly shortened the gastric transit time of solids and liquids (respectively 30% and 20% on average, p < 0.01). The incidence of gastrointestinal side-effects was similar with the two Erythromycin forms and the placebo. No correlation was found between the peak serum Erythromycin concentrations and the solid or liquid gastric half-lives. With the amorphous formulation, the area under the plasma time-concentration curves was small and solid and liquid gastric emptying were strongly accelerated, pointing to a direct effect on the gastrointestinal smooth muscle.
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effects of two oral Erythromycin Ethylsuccinate formulations on the motility of the small intestine in human beings
Antimicrobial Agents and Chemotherapy, 1996Co-Authors: F Caron, F Delatour, J C Torlotin, M Bouaniche, P Ducrotte, P Denis, G Humbert, B RouveixAbstract:Fourteen-membered macrolides are known to produce alterations in digestive tract motor activity; these include the induction of strong gastric contractions and a decrease in the motility of the small intestine. The aim of the study was to compare the effects of two different formulations of Erythromycin Ethylsuccinate (EE) on duodenojejunal motility. Compared with the more commonly used crystalline formulation of EE (CEE), the amorphous formulation (AEE) has previously been described to have greater bioavailability and to induce significantly fewer gastrointestinal side effects when given at therapeutic and what have been considered to be equivalent oral doses (i.e., CEE, 1,000 mg every 12 h; AEE, 500 mg every 12 h). In a crossover double-blind study, duodenojejunal manometric recordings were performed for 10 volunteers treated with placebo, CEE at 1,000 mg, or AEE at 500 mg. Recordings for each volunteer were obtained for a fed period after a standard dinner and then for a nocturnal fasting period. When compared with the placebo, CEE significantly decreased the motility index of the duodenum during the 30 min after the peak serum Erythromycin concentrations, shortened the duration of the fed state, and had no effect during the fasting state. In contrast, AEE did not significantly modify any motility parameter. Because AEE produced significantly lower concentrations in serum than CEE, these results do not necessarily imply that the two formulations of EE act differently on the motility of the small intestine.
Gilles Guibaud - One of the best experts on this subject based on the ideXlab platform.
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interaction of Erythromycin Ethylsuccinate and acetaminophen with protein fraction of extracellular polymeric substances eps from various bacterial aggregates
Environmental Science and Pollution Research, 2013Co-Authors: Romain Metivier, Isabelle Bourven, Jerome Labanowski, Gilles GuibaudAbstract:Extracellular polymeric substances (EPS) are, along with microbial cells, the main components of the biological sludges used in wastewater treatment and natural biofilms. EPS play a major role in removing pollutants from water by means of sorption. The ability of soluble EPS (S-EPS) and bound EPS (B-EPS) derived from various bacterial aggregates (flocs, granules, biofilms) to bind at pH 7.0 ± 0.1 to two pharmaceutical substances, acetaminophen (ACE) and Erythromycin Ethylsuccinate (ERY), has been investigated using the fluorescence quenching method. Two intense fluorescence peaks, A (Ex/Em range, 200–250/275–380 nm) and B (Ex/Em range, 260–320/275–360 nm), corresponding respectively to the aromatic protein region and soluble microbial by-product-like region, were identified in a three-dimensional excitation-emission matrix of EPS samples. The fluorescence peak, which corresponds to humic-like substances, was also identified though at low intensity. The ability of EPS to bind ACE was found to exceed that for ERY. The aromatic protein fraction of EPS displays a slightly higher affinity for drugs than that shown by the soluble microbial by-product-like fraction. The S-EPS and B-EPS present the same affinity for ACE and ERY. The effective quenching constants (log K) derived from the Stern–Volmer Equation equaled at peak A (with S-EPS): 3.7 ± 0.2 to 4.0 ± 0.1 for ACE and 2.1 ± 0.3 to 2.7 ± 0.1 for ERY. With B-EPS, these values were 3.9 ± 0.1 to 4.0 ± 0.1 for ACE and 2.0 ± 0.2 to 2.6 ± 0.1 for ERY. Our results suggest that the weaker EPS affinity for ERY than for ACE serves to partially explain why only about 50–80 % of ERY is removed from wastewater at the treatment plant. Moreover, this work demonstrates that EPS from natural river biofilms are able to bind drugs, which in turn may limit the mobility of drugs in natural waters.
Olga Vajdle - One of the best experts on this subject based on the ideXlab platform.
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voltammetric behavior of Erythromycin Ethylsuccinate at a renewable silver amalgam film electrode and its determination in urine and in a pharmaceutical preparation
Electrochimica Acta, 2016Co-Authors: Olga Vajdle, Valeria Guzsvany, Dusan Skoric, Jasmina Anojcic, Pavle Jovanov, Milka Avramovivic, Janos Csanadi, Zoltan Konya, Slobodan Petrovic, Andrzej BobrowskiAbstract:Abstract Erythromycin, a macrolide antibiotic, has similar antimicrobial spectrum to penicillin and it is widely used, especially in the treatment of patients who are allergic to penicillin. In this work, the application of a renewable silver-amalgam film electrode (Hg(Ag)FE) for the characterization and determination of Erythromycin Ethylsuccinate (EES), a widely used esterified form of this antibiotic, by means of cyclic voltammetry (CV) and square wave voltammetry (SWV) is presented. In the aqueous Britton-Robinson buffer (pH 5.0–9.0) that served as the supporting electrolyte, one reduction peak of EES was observed in the investigated potential range between −0.75 V and −1.80 V vs SCE, with peak potential maxima ranging from −1.59 V to −1.70 V, which strongly depended on the applied pH, as did the peak shape. For the analytical purposes the pH of 7.0 was selected, since in this electrolyte the EES peak was well-shaped and separated from the background current of the supporting electrolyte in both cases; in the direct cathodic SWV and in the case of square wave adsorptive stripping voltammetry (SW-AdSV). It was established, by the E p -pH correlation, that protons strongly influenced the electrochemical reduction of EES. The CVs recorded between 0.025–0.50 V s −1 at pH 7.0 confirmed that the electrode reaction is adsorption-controlled. Based on the series of 1 H NMR measurements it is proved that the tertiary amino group of EES is mainly in its protonated form at pH 7.0 which may lead, at appropriate accumulation potential and time, to the favored adsorption of the target ionic form of the analyte improving on such way the sensitivity of the SW-AdSV method. The optimized procedures resulted in stable SWV responses with good linear correlation in the EES concentration range from 4.53 to 29.8 μg mL −1 (LOD = 1.36 μg mL −1 ), and from 0.69 μg mL −1 to 2.44 μg mL −1 (LOD 0.21 μg mL −1 ) in the case of optimized SW-AdSV. The relative standard deviation is below 1.5%. The reliability of the elaborated procedures and thus the accuracy of the obtained results were validated by comparing them with those obtained by means of HPLC-DAD measurements. The direct cathodic SWV method was successfully applied for the determination of EES in the pharmaceutical preparation Eritromicin ® , while SW-AdSV was applied in the case of the spiked urine sample. In both cases, the standard addition method was used.