Cephalexin Concentration Research Articles

Evaluation of the recovery effects of antibiotic-resistant Lactiplantibacillus plantarum subsp. plantarum ATCC14917 on the antibiotic-disturbed intestinal microbiota using a mice model.

Supplementing Lactobacillus alongside antibiotic treatment was a curative strategy to modulate gut microbiota and alleviate antibiotic-associated dysbiosis. But the lactobacilli that are used as probiotics are sensitive or have a low level of resistance to antibiotics, so they usually cannot achieve their beneficial effect, since they are killed by the applied antibiotics. This work aimed to develop the highly resistant Lactiplantibacillus plantarum subsp. plantarum ATCC14917 to cephalexin and evaluate its recovery effects of antibiotic-resistant L. plantarum on the antibiotic-disturbed intestinal microbiota using a mice model. After successive growth in lactic acid bacteria susceptibility medium broth containing a gradually increasing concentration of cephalexin for 70 days, the minimum inhibitory concentration (MIC) of L. plantarum ATCC14917 to cephalexin significantly increased from 16 to 8192 μg ml-1, but stabilized at 4096 μg ml-1. After sequencing and sequence analysis, no mutated genes were detected on mobile elements, showing that horizontal transfer of mutated genes could not occur. Compared to the control group (Con), feeding mice with cephalexin (1mg ml-1; Cep) led to a decrease in alpha diversity. However, concurrently used cephalexin and L. plantarum (Cep+LpR) increased the alpha diversity in both microbial richness and diversity. The Cep+LpR group showed a lower distance with the Con group than either Cep or Cep+LpS groups, suggesting that resistant L. plantarum treatment was more effective than the original strain for the recovery of intestinal microbiota. Compared to the cephalexin-treated group, concurrent ingestion of cephalexin together with resistant L. plantarum significantly increased the proportion of beneficial bacteria and decreased Firmicutes/Bacteroidetes ratio and abundance of potential pathogens. The use of antibiotic-resistant L. plantarum ATCC14917 contributed to a much faster and richer recovery of the gut microbiota disturbed by antibiotic treatment compared to the original strain.

P-1222. Oral Cephalexin Population Pharmacokinetics and Target Attainment Analysis in Infants 0-60 Days Old

Abstract Background Transitioning from intravenous (IV) to oral (PO) antibiotics is uncommon practice in young infants due to a lack of pharmacokinetic (PK) or pharmacodynamic (PD) data to guide effective PO doses. Cephalexin is a promising PO treatment option against common neonatal pathogens, but rapid renal and intestinal maturation during the first months of life hinder extrapolation of dosing from older populations. In this study, we describe cephalexin’s PK in infants ≤ 60 days old and evaluate dosing regimens to achieve desired PD targets. Methods A prospective, single-center, open-label study was conducted to define cephalexin PK parameters in admitted infants 0-60 days old who were either receiving cephalexin clinically or were given a single oral study dose of cephalexin (25 mg/kg). Cephalexin plasma concentrations, quantified using liquid chromatography-mass spectrometry, were used for nonlinear mixed-effects modeling. Monte Carlo simulations were performed to assess the probability of various cephalexin dosing regimens to attain PD targets of free concentrations above the MIC (fT > MIC) for 40% and 70% of the day for MICs up to 8 mg/L (assuming 15% protein binding). Results The final analysis included 114 cephalexin concentrations obtained from 27 infants [median age: 31 days (range 9-56), gestational age: 37 wks (range 31-41)]. The data were best described using a one-compartment PK model with first order absorption and an absorption lag time. The covariates included in the final PK model were weight on apparent volume of distribution and apparent clearance (CL/F) using standard allometric scaling, post-natal age on absorption rate, and eGFR on CL/F. Cephalexin doses were simulated in 8 cohorts of virtual infants in weekly intervals from 1-8 weeks old assigned normal weights-for-age and eGFRs based on reference values. Conventional cephalexin dosing (25 mg/kg/dose q6 hrs) achieved a 40% fT > MIC PD target for every cohort and MIC range, and a 70% fT > MIC target in the 1, 2, and 3-week-old cohorts. Higher dosing was needed to achieve 70% fT > MIC in infants 4-8 weeks old. Conclusion Among infants ≤ 60 days, oral cephalexin can achieve high PD targets for efficacy against common neonatal pathogens with MIC ≤ 8 mg/L. These results provide dosing guidance to facilitate IV to PO transition in young infants. Disclosures Marc H. Scheetz, PharmD, MSc, Abbvie: Advisor/Consultant|Basilea: Advisor/Consultant|Cidara: Advisor/Consultant|DoseMe: Advisor/Consultant|Entasis: Advisor/Consultant|F2G: Advisor/Consultant|GSK: Advisor/Consultant|Lykos: Advisor/Consultant|Roche: Advisor/Consultant|Third Pole Therapeutics: Advisor/Consultant|Xelia: Advisor/Consultant Daniel Gonzalez, PharmD, PhD, Melinta Therapeutics, LLC: Advisor/Consultant|Nabriva Therapeutics plc: Grant/Research Support|Simulations Plus, Inc.: Advisor/Consultant Sonya Tang-Girdwood, MD, PhD, Kaizen Biosciences: Advisor/Consultant|Kaizen Biosciences: Grant/Research Support|Pfizer: Grant/Research Support Peter Anderson, PharmD, Gilead: Grant/Research Support

Investigation of Cephalexin Removal Using Biochar Derived from Nephelium lappaceum Seeds

<p class="MsoNormal" style="line-height:200%;margin-bottom:0cm;mso-layout-grid-align:none;text-align:justify;text-autospace:none;"><span style="font-family:"Times New Roman",serif;font-size:12.0pt;line-height:200%;" lang="EN-US">The improper disposal of drugs into bodies of water has become a severe environmental and health issue. Biochar synthesized from different agro residues could be a potential material for the adsorption of pollutants in aqueous environments. </span><em><i style="mso-bidi-font-style:normal;"><span style="font-family:"Times New Roman",serif;font-size:12.0pt;line-height:200%;" lang="EN-US">Nephelium lappaceum</span></i></em><span style="font-family:"Times New Roman",serif;font-size:12.0pt;line-height:200%;" lang="EN-US"> seeds were pyrolyzed at 600 °C in a pyrolysis reactor incorporating a slow pyrolysis process for carbonization. Fourier-Transform Infrared (FTIR), Scanning Electron Microscope (SEM), and X-ray diffraction (XRD) were used to characterize the biochar before and after adsorption of the pharmaceutical pollutant cephalexin. The effects of several factors, including initial cephalexin concentration, time of contact, dosage of adsorbent, and pH, were considered for the sorption. The findings showed that the Freundlich model offered the greatest fit for adsorption. The better-fitted kinetic model was the pseudo-second-order kinetic. Based on Langmuir isotherm model, the maximum adsorption capacity of cephalexin was obtained as 63.69 mg/g. The adsorption process involves hydrogen bonding, surface complexation, electrostatic and π−π EDA interactions. The current study offers a feasible and optimistic method for using agricultural waste and an alternative adsorbent substance for recovering highly concentrated cephalexin from water-based solutions.<o:p></o:p></span></p>

A hydrodynamic cavitation prototype reactor evaluation for decreasing cephalexin concentration in aqueous solution

A hydrodynamic cavitation prototype reactor evaluation for decreasing cephalexin concentration in aqueous solution

Adsorption of cephalexin from aqueous solutions by MIL-101 (Fe) metal–organic framework

Adsorption of cephalexin from aqueous solutions by MIL-101 (Fe) metal–organic framework

طريقة القياس الطيفي المتزامن لتقدير كل من سيبروفلوكساسين وسيفاليكسين باستخدام طريقة H - point للاضافة المعيارية

طريقة سهلة وبسيطة ودقيقة لتقدير السبروفلوكساسين في وجود السيفاليكسين او العكس بالعكس في خليط منهما. طبقت الطريقة المقترحة بطريقة الاضافة القياسية لنقطة بنجاح في تقدير السبروفلوكساسين بوجود السيفاليكسين كمتداخل عند الاطوال الموجية 240-272.3 نانوميتر وبتراكيز مختلفة من السبروفلوكساسين 4-18 مايكروغرام . مل-1 وكذلك تقدير السيفاليكسين بوجود السبروفلوكساسين الذي يتداخل باطوال موجية 262-285.7 نانوميتر وبتراكيز مختلفة من السيفاليكسين 6-18 مايكروغرام . مل-1 في مزيج لهما. اظهرت النتائج عدم وجود اي تداخلات من قبل المواد المضافة التي تحتويها الادوية على هذه المركبات وضمن حدود كشف السبروفلوكساسين يساوي 0.1732 مايكروغرام . مل-1 وعقارالسيفاليكسين يساوي 0.4620 مايكروغرام . مل-1 . الانحراف القياسي النسبي المئوي اقل من 2% . تم تطبيق الطريقة بنجاح لتقدير العقارين في بعض المستحضرات الصيدلانية. تعتبر الطريقة المقترحة من الطرق القليلة التكلفة وعدم حاجتها الى ادخال الادوية في سلسلة من التفاعلات وتثبيت لظروف التفاعل لغرض تقديرها وانما تتم عن طريق تقدير الدواء بعد اذابته مباشرة في الماء المقطر بوجود العقار الاخر معه في مزيج وتعتبر من الطرق الناجحة في التقدير خاصة للادوية المتقاربة في طيف الامتصاص لها والتي من غير الممكن ايجاد طرق لفصل الدوائين وتقديرهما بصورة ادق من هذه الطريقة المقترحة دون التداخل وتاثير احدهما على الاخر. الطريقة المقترحة في هذا البحث كانت ناجحة في تقدير كل من السبروفلوكساسين والسيفاليكسين في مزيج لهما دون تداخل دواء مع الاخر.

Exploration of cephalexin adsorption mechanisms onto bauxite and palygorskite and regeneration of spent adsorbents with cold plasma bubbling

The aim of the present study was the direct comparison of two popular minerals, bauxite and palygorskite, as adsorbents for the removal of cephalexin (CPX) from aqueous solutions and the regeneration of the spent adsorbents through cold atmospheric plasma. Batch kinetics and isotherm studies were carried out to evaluate the effect of contact time, initial CPX concentration, adsorbent dosage, pH and temperature. The adsorbents were characterized by ATR-FTIR, N2 sorption, SEM and XRD, while several isotherm, kinetic and thermodynamic models were evaluated attempting to shed light on the adsorption mechanisms. CPX adsorption on both adsorbents was better described by Langmuir model, with an adsorption capacity of 112.36 mg/g for palygorskite and 11.79 mg/g for bauxite. Thermodynamics revealed the endothermic and the spontaneous character of the process, indicating chemisorption as the main adsorption mechanism for both adsorbents. The pseudo-second-order and the Elovich models fitted satisfactorily the adsorption onto bauxite, while adsorption onto palygorskite was well presented by Weber–Morris model, indicating that pore diffusion is also involved in the process. The adsorption capacity of both minerals decreased significantly after being used for several adsorption cycles and then almost completely recovered (regeneration efficiency was 99.6% and 98% for palygorskite and bauxite, respectively) inside a novel cold plasma microbubble reactor energized by high-voltage nanopulses, revealing the potential of these adsorbents to be reused. In addition to the regeneration of the adsorbents, the cold plasma completely eliminated the CPX transferred from the solid to the aqueous phase during the regeneration process.

A novel Z-scheme heterojunction photocatalyst CeO2@WO3 nanocomposite with enhanced visible-light photocatalytic performance for wastewater treatment by cephalexin antibiotic degradation: Process optimization

A novel Z-scheme heterojunction photocatalyst CeO2@WO3 nanocomposite with enhanced visible-light photocatalytic performance for wastewater treatment by cephalexin antibiotic degradation: Process optimization

Low temperatures do not impair the bacterial plasmid conjugation on poultry meat.

Conjugation plays an important role in the dissemination of antimicrobial resistance genes. Besides, this process is influenced by many biotic and abiotic factors, especially temperature. This study aimed to investigate the effect of different conditions of temperature and storage (time and recipient) of poultry meat, intended for the final consumer, affect the plasmid transfer between pathogenic (harboring the IncB/O-plasmid) and non-pathogenic Escherichia coli organisms. The determination of minimal inhibitory concentrations (MIC) of ampicillin, cephalexin, cefotaxime, and ceftazidime was performed before and after the conjugation assay. It was possible to recover transconjugants in the poultry meat at all the treatments, also these bacteria showed a significant increase of the MIC for all antimicrobials tested. Our results show that a non-pathogenic E. coli can acquire an IncB/O-plasmid through a conjugation process in poultry meat, even stored at low temperatures. Once acquired, the resistance genes endanger public health especially when it is about critically and highly important antimicrobials to human medicine.

Syntheses and Characterization of Cephalexin-Chitosan/Natural Rubber network polymer for Slow-Release Fertilizer.

The increase in the world's population has forced the agricultural sector to increase the production of crops to meet food needs. The spread of nutrient deficiencies in the soil led to economic losses, a reduction in nutritional quality, and total grain quantity for humans and livestock. Coating fertilizers with polymers is one of the most important and effective aspects of slow-release fertilizers in the soil. aim this study, the reaction between chitosan and expired cephalexin as a grafted polymer was done and vulcanized with natural rubber in the presence of tetra methyl thiuram disulfide as catalyst to cover the urea fertilizer. The grafted polymer (chitosan/expired cephalexin compound) was prepared by the Schiff base method. The expired medicinal compound of cephalexin is rich in carbon, nitrogen, sulfur, and hydrogen atoms which improved the diffusion of the fertilizer .So the reaction of the validity of the reaction between chitosan and expired Cephalexin was confirmed by infrared (IR) and it was confirmed the presence of new absorption band due to the Azomethine group. The swelling, water retention, slow release of urea, and biodegradation of the NR/chitosan/expired cephalexin compounds were characterized. The rheometer test was carried out under the pressure of 250 bar and temperature of 170°C, The results showed that the Slow release of urea was increased with the increase in the concentration of cephalexin. The highest release percentage in soil media was 2.67 g/l for the C2 blend. The highest swelling ratio was 189.49 % for the C4 blend while the highest water retention was 75.67% for the C2 blend. It was also shown a good biodegradability, where the highest concentration of cephalexin with chitosan gave the highest rate of biodegradation to be 14.61% for C4. The homogeneity of the blends was studied by FE-SEM. It was concluded that the C1-C4 blends were the best for slow-release fertilizer application.

Improving bone regeneration with electrospun antibacterial polycaprolactone/collagen/polyvinyl pyrrolidone scaffolds coated with hydroxyapatite and cephalexin delivery capability

Electrospinning is a facile popular method for the creation of nano-micro fibers tissue engineering scaffolds. Here, polycaprolactone (PCL)/collagen (COL): polyvinyl pyrrolidone (PVP) scaffolds (PCL/COL: PVP) were fabricated for bone regeneration. Various concentrations of Cephalexin (CEF) (0.5, 1, 1.5 wt. %) were added to PCL/COL: PVP scaffold to provide an antibacterial scaffold, and different concentrations of hydroxyapatite (HA) (1, 2, 5 wt. %) was electrospray on the surface of the scaffolds. The PCL/COL: PVP scaffold contained 1.5% CEF and coated with 2% HA was introduced as the best sample and in-vitro tests were performed on this scaffold based on the antibacterial and MTT test results. Morphology observations demonstrated a bead-free uniform combined nano-micro fibrous structure. Fourier transform infrared spectroscopy and X-ray diffraction tests confirmed the successful formation of the scaffolds and the wettability, swelling, and biodegradability evaluations of the scaffolds confirmed the hydrophilicity nature of the scaffold with high swelling properties and suitable biodegradation ratio. The scaffolds supported cell adhesion and represented high alkaline phosphatase activity. CEF loading led to antibacterial properties of the designed scaffolds and showed a suitable sustained release rate within 48 h. It seems that the electrospun PCL/COL: PVP scaffold loaded with 1.5% CEF and coated with 2% HA can be useful for bone regeneration applications that need further evaluation in the near future.

Pharmacokinetic-Pharmacodynamic Analysis of Cephalexin against Streptococcus parauberis in Olive Flounder (Paralichthys olivaceus: Temminck and Schlegel)

Olive flounders are susceptible to annual outbreaks of streptococcosis, which accounts for approximately 10% of all fish farm diseases and is associated with high mortality rates. The development of an antibiotic therapy against streptococcosis is thus necessary. This study determined the therapeutic effects of varying cephalexin concentrations in Streptococcus parauberis-infected olive flounders and evaluated its histopathological toxicity and residual concentration in the fish. Compared with the control group, the 200 and 800 mg/kg cephalexin groups showed significant mean survival rates of approximately 10% and 30%, respectively, and the 400 mg/kg group showed the highest survival rate of approximately 40%. The average residual cephalexin concentration in muscle samples on day 1 post-cephalexin administration was 13.21 µg/kg, showing a rapid decrease. At the optimum water temperature (25°C), cephalexin was rapidly metabolized within 24 hr of its administration being terminated, and most of it was excreted from the bodies of the fish. A histopathological analysis showed that the oral administration of cephalexin did not lead to specific inflammatory lesions, and there were no significant differences between the treatment and control groups. Our novel findings suggest that cephalexin is a promising candidate for treating streptococcosis outbreaks in fish farms.

A sustainable system for decontamination of cephalexin antibiotic using electrocoagulation technology and response surface methodology

AbstractThe emergence of synthetic micropollutants in wastewater due to domestic and industrial use has presented new challenges for treatment processes. Among these pollutants, pharmaceutical and personal care products (PPCPs) are considered emerging contaminants due to their potential to enter drinking water sources. Antibiotics, in particular, are of significant concern due to their high consumption in veterinary and human applications. In this study, the electrocoagulation (EC) process is used as an efficient technique for the removal of cephalexin (CFX) from pharmaceutical wastewater. The study aims to explore the ability of the EC process to remove CFX and optimize its performance using the response surface method based on Central Composite Design (RSM‐CCD). The effects of initial CFX concentration, electrolysis time, initial pH, and electrode type (non‐insulated and insulated) were considered in the optimization process. This research is distinct as it examines the influence of key factors on the elimination of CFX. The results showed that electrolysis time had the most significant effect on CFX removal using the EC process. The analysis of variance (ANOVA) test was used to evaluate the importance of independent variables and their interaction. The optimal operating conditions for maximum removal efficiency (86.53%) were an initial CFX concentration, reaction time, and initial pH of 34 mg/L, 34.35 min, and 6.5, respectively, using an insulated electrode. Under these optimal conditions, predicted CFX removal was 93.54%. These findings demonstrate that RSM‐CCD is a useful tool for optimizing electrochemical removal processes for micropollutants such as CFX from wastewater streams. The study highlights the importance of considering electrode type in optimizing EC processes for micropollutant removal from wastewater.

Nanofiltration membrane with CM-β-CD tailored polyamide layer for high concentration cephalexin solution separation

Nanofiltration membrane with CM-β-CD tailored polyamide layer for high concentration cephalexin solution separation

Comparative Study on Photocatalytic Performance of TiO2 Doped with Different Amino Acids in Degradation of Antibiotics

In this study, three different reusable photocatalysts containing different amino acids as a source of non-metals, including L-Arginine, L-Proline, and L-Methionine, have been synthesized for the first time. Using a kinetic study and degradation efficiency test, these visible driven photocatalysts were investigated for their photocatalytic activity in removing antibiotics, including metronidazole (MNZ) and cephalexin (CEX). The morphology, structure and optical properties of the fabricated catalysts were characterized by X-ray Powder Diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive Spectrometry (EDS)/mapping, Fourier-Transform Infrared Spectroscopy (FTIR), Photoluminescence Spectroscopy (PL) and UV-Vis Diffuse Reflectance Spectroscopy (DRS) analyses. Based on the results of the PL analysis, it was confirmed that doping TiO2 with amino acids containing C, N, and S inhibited the recombination of induced electrons and holes. Among the three catalysts, L-Arginine-TiO2 demonstrated the highest photocatalytic activity for antibiotic degradation, followed by L-Proline-TiO2. According to the response surface methodology (RSM), the optimum operating conditions were a concentration of 50 mg/L MNZ, pH = 4, and catalyst concentration = 1.5 g/L under 90 min of irradiation time. At this condition, 99.9% of MNZ and 81% of TOC were removed. In addition, 97.2% of CEX and 75% TOC were eliminated at the optimum conditions of 1g/L catalyst concentration, 50 mg/L CEX concentration, at neutral pH, and after 120 min irradiation. L-Arginine (1 wt.%)-TiO2 was tested for stability and reusability, and it showed that after five cycles, 10% of its performance had been lost. The role of reactive species in photocatalysis was identified and •OH had the most significant impacts on MNZ and CEX photodegradation. Antibiotic degradation efficiency was adversely affected by the presence of anions and humic acid, but this reduction was not significant for inorganic anions, as only 13% of degradation was lost.

Potentiodynamic Poly(resorcinol)-Modified Glassy Carbon Electrode as a Voltammetric Sensor for Determining Cephalexin and Cefadroxil Simultaneously in Pharmaceutical Formulation and Biological Fluid Samples.

This study covers the development of a fast, selective, sensitive, and stable method for the simultaneous determination of cephalosporins (cephalexin (CLN) and cefadroxil (CFL)) in biological fluids and tablet samples using potentiodynamic fabrication of a poly(resorcinol)-modified glassy carbon electrode (poly(reso)/GCE). The results of cyclic voltammetry and electrochemical impedance spectroscopy supported the modification of the GCE by a polymer layer that raised the electrode surface area and conductivity. At the poly(reso)/GCE, an irreversible oxidative peak with four- and fivefold current enhancement for CLN and CFL, respectively, at a substantially lower potential demonstrated the catalytic action of the modifier. Under optimized solution and parameters, the peak current response at the poly(reso)/GCE revealed a linear dependence on the concentration of CLN and CFL within the range 0.1–300 and 0.5–300 μM, respectively, with a limit of detection (LoD) of 3.12 and 8.7 nM, respectively. The levels of CLN in four selected tablet brands and CFL in two tablet brands were in the vicinity of 91.00–103.65% and 97.7–98.83%, respectively, of their nominal values. The recovery results for CLN in pharmaceutical samples were in the range of 99.00–100.67% and for CFL 97.9–99.75% and for blood serum and urine samples 99.55–100.55% and 99.33–100.34% for CLN and 97.13–100.60% and 96.73–102.50% for CFL, respectively. Interference recovery results with errors less than 4.81%, lower LoD, wider dynamic range, excellent recovery results, and good stability of the modifier compared to those for the previously reported methods validated the use of the poly(reso)/GCE for determining CLN and CFL simultaneously in various real samples.

WO3/Ag/ZnO S-scheme heterostructure thin film spinning disc photoreactor for intensified photodegradation of cephalexin antibiotic

The presence of antibiotics in wastes and drinking water has led to serious environmental and health concerns, further necessitating the development of an advanced sustainable strategy to eliminate antibiotics from aquatic media. In this context, the present research reports the successful fabrication of a spinning disc photoreactor (SDPR) supported ZnO/Ag/WO3 S-scheme visible-light-driven thin-film photocatalyst to study the degradation of cephalexin (CPX) as a target pollutant under blue light irradiation. The optical, electrochemical and physicochemical characterization of the as-prepared thin-film samples were carried out by XRD, top-view FE-SEM, EDS-mapping, UV-Vis-DRS, contact angle, EIS, transient photocurrent, mott Schottky and AFM techniques. The rod shape morphology of the samples with moderate surface roughness, desirable hydrophobicity, low bandgap and remarkable band structure alignment confirmed the applicability of as-prepared thin-film with an average photon flux of 1.94×10-4-8.61×10-5E's m-2 s-1. The use of a rotating catalytic disc impressively declined the photon propagation distance, decremented the probability of light absorption by the solution, and intensified the mass transfer rate. The maximum throughputs of 98.8% efficiencies for CPX degradation were achieved at a rotational speed of 180rpm, the solution flow rate of 1.0Lmin-1, the light intensity of 11mWcm-2, and initial CPX concentration of 40mgL-1, illumination time of 80min, and pH of 6. Damkohler number (Da) value was found to be 1.23×10-2at the optimum conditions, indicating the negligibility of the external mass transfer resistance in the SDPR. The photocatalytic mechanism was elucidated for finding the most operative radical species, suggesting the crucial role of ·O2- in photodegradation of CPX and a drastic improvement of the charge separation by S-scheme heterostructure and facilitation by Ag mediator. Findings indicated that the developed reusable and robust SDPR benefited from an s-scheme photocatalyst can be a promising technology for degradation of the organic compounds.

Evaluation of cephalexin-loaded PHBV nanofibers for MRSA-infected diabetic foot ulcers treatment

The delayed and compromised diabetic foot ulcers (DFUs) healing due to methicillin resistance staphylococcus aureus (MRSA) is an emerging threat to human health and life. Developing new strategies to clear bacteria from ulcerative regions can be helpful to treat DFUs. The current study was designed to fabricate poly (3-hydroxy butyric acid-co-3-hydroxy valeric acid, (PHBV)), nanofibers (PHBV NFs) loaded with cephalexin (CPL) by electrospining technique to improve the bioavailability of CPL at the wound site to inhibit the bacterial growth and trigger the ulcer healing process. Morphological analysis shown that the electrospun nanofibers exhibited smooth surface morphology with an average diameter ranges from 205 ± 25 to 450 ± 55 nm, depending on the cephalexin concentration. The prepared nanofibers showed an enhanced drug loading capacity (LC) and entrapment efficiency (EE) of about 12.1 ± 1.6% and 75.3 ± 2%, respectively. The successful drug loading was also confirmed by FTIR analysis. Moreover, the CPL-loaded PHBV NFs exhibited high water uptake and biodegradation rate compared to blank PHBV NFs. The drug-loaded NFs initially showed a burst drug release followed by a sustained drug release profile with a constant rate up to 48 h. In-vitro studies show that CPL-loaded PHBV NFs exhibited an enhanced antibacterial activity against MRSA strains and have no visible toxic effect against keratinocytes, L929 and HEK293T cell lines. Further, CPL-loaded PHBV NFs showed the enhanced in-vivo bacterial clearance from DFUs using NcZ10 diabetic mice model compared to free CPL. Collectively, our results demonstrated that CPL-loaded PHBV NFs can be applied as a favorable dressing material to treat MRSA-infected chronic DFUs.

A high-performance microreactor integrated with chitosan/ Bi2WO6/CNT/TiO2 nanofibers for adsorptive/photocatalytic removal of cephalexin from aqueous solution

A Z-scheme Bi2WO6/CNT/TiO2 photocatalyst was synthesized hydrothermally and loaded on chitosan nanofibers with different mass percentages using the electrospinning process. The batch adsorption experiments for chitosan nanofibrous samples containing Bi2WO6/CNT/TiO2 revealed that the adsorption process and its kinetic followed the Langmuir isotherm and pseudo-second-order model, respectively. A planar microreactor with a reusable plate-type configuration was fabricated employing an inexpensive micromachining technique and integrated with chitosan/Bi2WO6/CNT/TiO2 nanofibers. The synergistic effect of the adsorption and photocatalysis was assessed for removing cephalexin under simulated sunlight irradiation in a continuous flow microreactor. The nanofibers containing 15wt% of Bi2WO6/CNT/TiO2 exhibited the most removal efficiency. The effects of operational variables were investigated in the microreactor and optimized using response surface methodology as light intensity=17.45W/m2, retention time=256s, pH=4.8, and initial cephalexin concentration=29mg/L. At this condition, cephalexin and TOC removal efficiencies reached 99.2% and 92.4%, respectively. The kinetic of disappearance of cephalexin under optimal conditions followed the Langmuir-Hinshelwood model. The adsorption equilibrium constant deduced from this model was similar to that one calculated from the Langmuir isotherm model. At the optimum condition, cephalexin removal efficiency reduced to 80% after 1500min of microreactor operation and the nanofibers revealed appropriate stability and reusability.

Applications of Computational and Statistical Models for Optimizing the Electrochemical Removal of Cephalexin Antibiotic from Water

One of the most serious effects of micropollutants in the environment is biological magnification, which causes adverse effects on humans and the ecosystem. Among all of the micro-pollutants, antibiotics are commonly present in the aquatic environment due to their wide use in treating or preventing various diseases and infections for humans, plants, and animals. Therefore, an aluminum-based electrocoagulation unit has been used in this study to remove cephalexin antibiotics, as a model of the antibiotics, from water. Computational and statistical models were used to optimize the effects of key parameters on the electrochemical removal of cephalexin, including the initial cephalexin concentration (15–55 mg/L), initial pH (3–11), electrolysis time (20–40 min), and electrode type (insulated and non-insulated). The response surface methodology-central composite design (RSM-CCD) was used to investigate the dependency of the studied variables, while the artificial neural network (ANN) and adaptive neuro-fuzzy inference system (ANFIS) methods were applied for predicting the experimental training data. The results showed that the best experimental and predicted removals of cephalexin (CEX) were 88.21% and 93.87%, respectively, which were obtained at a pH of 6.14 and electrolysis time of 34.26 min. The results also showed that the ANFIS model predicts and interprets the experimental results better than the ANN and RSM-CCD models. Sensitivity analysis using the Garson method showed the comparative significance of the variables as follows: pH (30%) > electrode type (27%) > initial CEX concentration (24%) > electrolysis time (19%).