Antibacterial properties and release kinetics of chlorhexidine diacetate from montmorillonite and palygorskite clays

2019 ◽  
Vol 34 (8) ◽  
pp. 1052-1058
Author(s):  
Héctor A Lobato-Aguilar ◽  
Gabriel Lizama-Uc ◽  
Jorge A Uribe-Calderon ◽  
Juan Cauich-Rodriguez ◽  
Nayeli Rodriguez-Fuentes ◽  
...  

Organoclays were prepared by means of cation-exchange reactions using different concentrations of chlorhexidine diacetate and two different types of clays: montmorillonite and palygorskite. The antibacterial activity against Escherichia coli was evaluated by means of disk diffusion tests as well as through bacterial growth inhibition (monitored by optical density measurements) in Luria broth media. Results indicate that modified palygorskites showed a greater antibacterial activity than those exhibited by modified montmorillonite, as latter only displayed antibacterial properties at the highest chlorhexidine diacetate loading. Modeling of chlorhexidine release was also performed and the models best described the drug release phenomena depended on the type of clay; being the Higuchi model and Korsemeyer–Peppas model for montmorillonite, whereas the zero-order model and Korsemeyer–Peppas model for palygorskite.

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Claudio Poggio ◽  
Carla Renata Arciola ◽  
Riccardo Beltrami ◽  
Annachiara Monaco ◽  
Alberto Dagna ◽  
...  

The aim of this study was to evaluate and compare the antimicrobial activity and cytocompatibility of six different pulp-capping materials: Dycal (Dentsply), Calcicur (Voco), Calcimol LC (Voco), TheraCal LC (Bisco), MTA Angelus (Angelus), and Biodentine (Septodont). To evaluate antimicrobial activity, materials were challengedin vitrowithStreptococcus mutans,Streptococcus salivarius, andStreptococcus sanguisin the agar disc diffusion test. Cytocompatibility of the assayed materials towards rat MDPC-23 cells was evaluated at different times by both MTT and apoptosis assays. Results significantly differed among the different materials tested. Both bacterial growth inhibition halos and cytocompatibility performances were significantly different among materials with different composition. MTA-based products showed lower cytotoxicity and valuable antibacterial activity, different from calcium hydroxide-based materials, which exhibited not only higher antibacterial activity but also higher cytotoxicity.


Author(s):  
Adil Patel ◽  
Ami Kalsariya ◽  
Srushti Patel ◽  
Chandni Patel ◽  
Shreya Patel

The aim of present work is to determine and analyse the kinetics of drug release from the fast dissolving sublingual by employing various mathematical models. A study was done with Cyanocobalamine fast dissolving sublingual films, 1.5 mg/film by employing solvent casting technique using dehydrated banana starch and Gelatin. The in-vitro drug release profile was carried out in pH 6.8 phosphate buffer (900 mL) using USP dissolution apparatus I (Basket) at 50 rpm for 20 mins. The drug release data was obtained, quantitatively correlated and interpreted with various mathematical models viz. Zero order model, first order model, Higuchi model, Hixson-Crowell model and Korsmeyer-Peppas model and evaluated to understand the kinetics of drug release. The criterion for the most suitable model was based on the high degree of coefficient of correlation of drug release profile of Cyanocobalamine fast dissolving sublingual films.


2021 ◽  
Vol 11 (19) ◽  
pp. 9311
Author(s):  
Michelina Catauro ◽  
Ylenia D’Errico ◽  
Antonio D’Angelo ◽  
Ronald J. Clarke ◽  
Ignazio Blanco

The aim of this work was the synthesis of hybrid materials of iron (II)-based therapeutic systems via the sol-gel method. Increasing amounts of polyethylene glycol (PEG 6, 12, 24, 50 wt%) were added to SiO2/Fe20 wt% to modulate the release kinetics of the drug from the systems. Fourier-transform infrared (FTIR) spectroscopy was used to study the interactions between different components in the hybrid materials. The release kinetics in a simulated body fluid (SBF) were investigated, and the amount of Fe2+ released was detected via ultraviolet-visible spectroscopy (UV-Vis) after reaction with ortho-phenanthroline. Furthermore, biological characterization was carried out. The bioactivity of the synthesized hybrid materials was evaluated via the formation of a layer of hydroxyapatite on the surface of samples soaked in SBF using spectroscopy. Finally, the potential antibacterial properties of seven different materials against two different bacteria—E. coli and S. aureus—were investigated.


2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Y. Santhosh Kumar ◽  
Langeswaran Kulanthaivel ◽  
G. S. Hikku ◽  
R. Saravanan ◽  
Thangavelu Lakshmi ◽  
...  

Kaempferol and combretastatin are polyphenolic compounds derived from plant sources which are known for their antibacterial activity. However, owing to their large size and water insolubility, their antibacterial activity is limited. In this context, the present study focused on the nanoformulation of kaempferol (NF-k) and combretastatin (NF-c) and their influence on water solubility and antibacterial properties. The NF-k and NF-c were prepared using the solvent evaporation method and were thoroughly characterized for evaluating the morphology, molecular vibrations, size, etc. Based on the results, it is observed that the pristine forms of kaempferol and combretastatin drugs get nanoformulated and completely soluble in water. Using particle size analyzer, the particle sizes of NF-k and NF-c were estimated as 334 nm and 260 nm, respectively, which are very fine compared to pristine kaempferol and combretastatin (5193 nm and 1217 nm, respectively). The molecular vibrations that exist in NF-k and NF-c were confirmed by the Fourier transform infrared spectra, where the nanoformulated drug showed lower intensities than the pristine form of kaempferol and combretastatin. The drug release kinetics of the nanoformulated drugs were carried out using the dialysis membrane method and were compared with their pristine forms. Owing to the size effect, the NF-k and NF-c release up to 50% of the drug in a sustained manner till 50 h showing twofold higher concentration than the control where it released 25%. The antibacterial activity was assessed by measuring the optical density at 600 nm using UV-vis spectrophotometer and displayed significant activity against gram-positive Staphylococcus aureus strain. The mechanisms behind the antibacterial activity of NF-k and NF-c were discussed in detail. The activation of ATP-dependent efflux pump system and the blockage of porin channels could be the cause for the bactericidal activity. Our understanding of efflux pumps and their role in antibacterial activity is still in its early stages. No studies have been performed to date using nanoformulations of kaempferol and combretastatin to investigate their roles. This complicates the determination of the exact mechanisms acting against bacterial growth when using nanoformulation drugs. Our increasing knowledge of water-soluble nanoformulation drugs and their roles in reduced bacterial activity will pave the way to developing effective treatments in the future.


2017 ◽  
Vol 2017 ◽  
pp. 1-11 ◽  
Author(s):  
Erika Adomavičiūtė ◽  
Solveiga Pupkevičiūtė ◽  
Vaida Juškaitė ◽  
Modestas Žilius ◽  
Sigitas Stanys ◽  
...  

An electrospun hydrophilic non-water-soluble biocompatible polylactic acid (PLA) nonwoven material was used as a delivery system for propolis ethanolic extract (PEE) and silver nanoparticles (AgNPs) that are known for their established antiseptic and antimicrobial activity. Combination of PEE and AgNPs in a single product should provide efficient antimicrobial protection and improved wound healing. Evaluations of PEE and AgNPs on morphology of electrospun materials, release kinetics of AgNPs and phenolic compounds, antibacterial properties, and cytotoxicity of electrospun PLA materials were performed. The presence of PEE or/and AgNPs resulted in denser mats formed by thicker PLA fibers. The average diameter of PLA microfibers was 168±29 nm. The average diameter of microfibers increased to 318±40 and 370±30 nm when 10 wt% and 20 wt% ethanol were added, respectively. Addition of 10 wt% or 20 wt% PEE increased the diameter to 282±25 and 371±25 nm, respectively. Suspension of AgNPs also caused the formation of thicker microfibers with 254±25 nm diameter. Electrospun PLA microfibers with PEE maintained viability of HaCaT cells. Testing of antimicrobial activity confirmed the ability of AgNPs containing PLA electrospun materials to inhibit the growth of microorganisms.


2020 ◽  
Vol 2 (1) ◽  
pp. 25

Nanocarriers can be used to carry different types of materials, for instance, drugs, and play a major role in therapy. In this study, gum was collected and subjected to water extract, used for various bioactive studies. It was purified and characterized. The purified gum was used for nanocarrier synthesis, where sodium trimetaphosphate (STMP) was utilized to synthesize nanocarriers. The gum extract was observed to have antioxidant and antibacterial properties. UV-Vis, SEM, AFM, zeta potential, and FTIR analysis were performed. By these analyses, the nanocarriers were found to be stable for the delivery of the drug. The best antibacterial activity was observed in the loaded nanocarriers.


1985 ◽  
Vol 227 (2) ◽  
pp. 373-378 ◽  
Author(s):  
U Jönsson ◽  
M Malmqvist ◽  
I Rönnberg

The kinetics of, and the influence of ionic strength on, the immobilization of rabbit immunoglobulin G (IgG) on different types of well-characterized silica surfaces were investigated. Adsorptive immobilization was compared with covalent attachment via thiol-disulphide exchange reactions. The amount of immobilized IgG on five different types of silica surfaces as a function of IgG concentration, at two different ionic strengths, was determined. The IgG-solid-surface interaction involved different types of interaction forces, depending on the surface chemistry of the solid surface. The solid-surface chemistry is an important parameter determining the immobilized amount of IgG. When conditions for covalent attachment of IgG to the surfaces were fulfilled, the IgG showed high affinity and the immobilized amount of IgG showed a fast saturation. Changes in ionic strength showed no significant influence on the kinetics of immobilization on these surfaces. The amount of covalently attached IgG was partially ionic-strength-dependent, indicating that adsorptive interactions were involved. The results are of fundamental interest for the development of new immunosensors based on surface-concentration-measuring devices.


2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Shivaraj Ninganagouda ◽  
Vandana Rathod ◽  
Dattu Singh ◽  
Jyoti Hiremath ◽  
Ashish Kumar Singh ◽  
...  

Silver Nanoparticles (AgNPs), the real silver bullet, are known to have good antibacterial properties against pathogenic microorganisms. In the present study AgNPs were prepared from extracellular filtrate ofAspergillus niger. Characterization of AgNPs by UV-Vis spectrum reveals specific surface plasmon resonance at peak 416 nm; TEM photographs revealed the size of the AgNPs to be 20–55 nm. Average diameter of the produced AgNPs was found to be 73 nm with a zeta potential that was −24 mV using Malvern Zetasizer. SEM micrographs showed AgNPs to be spherical with smooth morphology. EDS revealed the presence of pure metallic AgNPs along with carbon and oxygen signatures. Of the different concentrations (0, 2.5, 5, 10, and 15 μg/mL) used 10 μg/mL were sufficient to inhibit 107 CFU/mL ofE. coli. ROS production was measured using DCFH-DA method and the the free radical generation effect of AgNPs on bacterial growth inhibition was investigated by ESR spectroscopy. This paper not only deals with the damage inflicted on microorganisms by AgNPs but also induces cell death through the production of ROS released by AgNPs and also growth kinetics ofE. colisupplemented with AgNPs produced byA. niger.


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