Optimization of arsenite removal by adsorption onto organically modified montmorillonite clay: Experimental & theoretical approaches

Arsenic is a critical contaminant for aqueous environments as it poses harmful health risks. To meet the stringent regulations regarding the presence of arsenic in aqueous solutions, the feasibility of montmorillonite clay modified with hexadecyltrimethyl ammonium chloride as the adsorbent was tested for the removal of arsenic ions from aqueous solutions. A scanning electron microscopy (SEM) study confirmed that the organically modified nanoclay (ONC) adsorbent had a porous structure with a vast adsorbent surface.The x-ray fluorescence (XRF) analysis proved the presence of carbon in the structure of the modified nanoclay that can be evidence for the creation of ONC. The x-ray diffraction (XRD) analysis results confirm the existence of four main groups of minerals, carbonate (Calcite), clay (Askmtyt and Kandyt), silicate (Quartz), and phyllosilicate (Kaolinite), in the ONC structure.The influence of various parameters such as solution pH, adsorbent dosage, initial arsenite concentration, and contact time on arsenic adsorption onto ONC was investigated. A 2(5) full factorial central composite experimental design was applied. A central composite design under response surface methodology (RSM) was employed to investigate the effects of independent variables on arsenite removal and to determine the optimum condition. The experimental values were in a good fit with the ones predicted by the model. The optimal operating points (adsorbent dosage: 3.7 g L-1, surfactant dosage: 3 g L-1 and the contact time: 37.2min) giving maximum arsenite removal (95.95) were found using Solver "Add-ins" in Microsoft Excel 2010

Anal tuberculosis: A non–Healing anal lesion

Anal tuberculosis is an extremely rare extrapulmonary presentation of tuberculosis (TB). Less than 1% of the individuals who contract TB manifests as gastrointestinal TB, and anoperineal TB is much less frequently encountered, 1% of the TB cases of the digestive tract. A rare case of anal tuberculosis is reported in a 37-year-old male patient with a recent anal fistula surgery and relapsing anal lesions. AFB were detected by biopsy and culture. In total, the treatment course lasted 6 months and the patient showed signs of recovery in the early stages of the treatment (after 2 weeks), and complete remission was achieved. In conclusion, it is recommended that in case of encountering Non-healing and recurrent anal lesions, especially in regions endemic for TB, should be evaluated for tuberculosis. Keywords: Anal, Tuberculosis, Fistula surger

Potentiometric sensing of lamotrigine based on molecularly imprinted polymers

In the present work a novel potentiometric sensor, based on a noncovalent imprinted polymer, was developed for determination of Lamotrigine (LTG). At optimized conditions the electrode exhibited a Nernstian response (30.8±1.0mV decade-1) in a concentration range of 1�10-6 to 1�10-3M with a detection limit of 8�10-7mol L-1. The potential response of the electrode was constant in the pH range of 1.0-5.0. The electrode demonstrated a response time of ~30s. The selectivity coefficient of the sensor toward a number of different drugs with molecular similarities and some metal ions was evaluated. The electrode was examined for determination of LTG in real samples. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Synthesis and characterization of novel antibacterial PdDA/ honey nanofiber against Gram-positive and Gram-negative bacteria

Nanomaterials are increasingly used to the targeting of gram-positive and gram-negative bacteria as an alternative to antibiotics. Bacterial infections are a major cause of chronic infections and mortality. People requirement for new materials for pathogenic bacteria treatment. It seems that nanomaterial-based strategies can be resolving this problem. In this research, improved antibacterial nanofibrous material using the synthesis of novel blend nanofibers by electrospinning method against gram-positive and gram-negative bacteria. First, Honey as a natural, biocompatible and antimicrobial compound (with different percentages) was added to the PDDA solution and the influence of processing parameters on the morphology of the electrospun blend nanofibers were investigated. The results showed that a bead-free morphology of nanofibers with uniform diameter achieved at the concentration ratio of 40/60 (PDDA/honey), the flow rate of 0.8 mL/h and the high voltage of 17kV. The sample with optimum morphology was cross-linked by glutaraldehyde at different crosslinking times. Evaluation of the water absorption property of nanofibers showed the absorption capacity of 4.9 g/g. Then, the in-vitro antibacterial activity of nanofiber investigated against gram-positive and gram-negative strains, Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). Afterward, novel nanofiber antibacterial activity studied against pathogenic Pseudomonas aeruginosa (P. aeruginosa). The MIC values indicated that the ratio of 40/60 PDDA/honey nanofiber induced about 99.9 bacterial death for both strains. Moreover, the novel PDDA/honey nanofibers showed suitable antibacterial activity (98.89 ) against pathogenic Pseudomonas aeruginosa. Moreover, the results showed a large reduction of bacterial numbers and evidently presented novel nanofibers as new antimicrobial agents. © 2020 Nanomedicine Research Journal. All rights reserved

Drug penetration enhancement techniques in ablative fractional laser assisted cutaneous delivery of indocyanine green

Background and Objectives: Topical drug delivery can be increased by pretreatment of the skin with ablative fractional laser (AFXL). Several physical penetration enhancement techniques have been investigated to further improve AFXL-assisted drug delivery. This study investigated the influence of three of these techniques, namely massage, acoustic pressure wave treatment, and pressure vacuum alterations (PVP) on the distribution of the fluorescent drug indocyanine green (ICG) at different depths in the skin after topical application on AFXL pretreated skin. Materials and Methods: In ex vivo human skin, test regions were pretreated with AFXL (10,600 nm, channel depth 300 μm, channel width 120 μm, density 15%). Subsequently, ICG was applied, followed by massage, acoustic pressure wave treatment or PVP. ICG fluorescence intensity (FI) was assessed after 1, 3, and 24 hours at several depths using fluorescence photography. Results: FI was higher when using enhancement techniques compared to control (AFXL-only) up to 3 hours application time (P < 0.05). After 3 hours, mean surface FI was highest after acoustic pressure wave treatment (61.5 arbitrary units; AU), followed by massage (57.5AU) and PVP (46.9AU), respectively (for comparison: AFXL-only 31.6AU, no pretreatment 14.9AU). Comparable or higher FI was achieved already after 1 hour with enhancement techniques compared to 3–24 hours application time without. After 24 hours, no significant differences between enhancement techniques and AFXL-only were observed (P = 0.31). Conclusion: Penetration enhancement techniques, especially acoustic pressure wave treatment and massage, result in improved drug accumulation in AFXL-pretreated skin and reduce the application time needed. Lasers Surg. Med. © 2019 The Authors. Lasers in Surgery and Medicine Published by Wiley Periodicals, Inc