Enhanced Antimicrobial Action of Chlorhexidine Loaded in Shellac Nanoparticles with Cationic Surface Functionality

We report on an active nanocarrier for chlorhexidine (CHX) based on sterically stabilized shellac nanoparticles (NPs) with dual surface functionalization, which greatly enhances the antimicrobial action of CHX. The fabrication process for the CHX nanocarrier is based on pH-induced co-precipitation of CHX-DG from an aqueous solution of ammonium shellac and Poloxamer 407 (P407), which serves as a steric stabilizing agent. This is followed by further surface modification with octadecyl trimethyl ammonium bromide (ODTAB) through a solvent change to yield cationic surface functionality. In this study, we assessed the encapsulation efficiency and release kinetics of the novel nanocarrier for CHX. We further examined the antimicrobial effects of the CHX nanocarriers and their individual components in order to gain better insight into how they work, to improve their design and to explore the impacts of their dual functionalization. The antimicrobial actions of CHX loaded in shellac NPs were examined on three different proxy microorganisms: a Gram-negative bacterium (E. coli), a yeast (S. cerevisiae) and a microalgae (C. reinhardtii). The antimicrobial actions of free CHX and CHX-loaded shellac NPs were compared over the same CHX concentration range. We found that the non-coated shellac NPs loaded with CHX showed inferior action compared with free CHX due to their negative surface charge; however, the ODTAB-coated, CHX-loaded shellac NPs strongly amplified the antimicrobial action of the CHX for the tested microorganisms. The enhancement of the CHX antimicrobial action was thought to be due to the increased electrostatic adhesion between the cationic surface of the ODTAB-coated, CHX-loaded shellac NPs and the anionic surface of the cell walls of the microorganisms, ensuring direct delivery of CHX with a high concentration locally on the cell membrane. The novel CHX nanocarriers with enhanced antimicrobial action may potentially find applications in dentistry for the development of more efficient formulations against conditions such as gingivitis, periodontitis and other oral infections, as well as enabling formulations to have lower CHX concentrations.

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Soft Malleable Vesicles: versatile carriers for efficient topical delivery of fungal therapeutics

Drug Research ◽

10.1055/a-1286-5750 ◽

2020 ◽

Author(s):

Preeti Gupta ◽

Antesh Kumar Jha ◽

Mahesh Prasad ◽

Poonam Kushwaha

Keyword(s):

Topical Treatment ◽

Healthcare Professionals ◽

Fungal Infections ◽

Topical Delivery ◽

Systemic Circulation ◽

Skin Permeability ◽

Low Permeability ◽

The Novel ◽

High Concentration ◽

Efficient Delivery

AbstractFungal infections have become a subject of great concern and the incidence of fungal infections is increasing, presenting an enormous challenge to healthcare professionals. Since most of the fungal infections are occurring over the skin, the treatment option of these infections always involves topical application. However, in topical delivery drug reaches into systemic circulation through different barriers of skin. Nevertheless, due to the low permeability, skin restricts the movement of many drugs. Hence, a delivery system is required, which deliver the medicament into the skin layers or through the skin and into the systemic circulation. Ethosomes or Soft malleable vesicles are the novel lipid vesicular carrier that offer improved skin permeability and efficient delivery due to their structure and composition. They contain high concentration of ethanol, which increases the fluidity of the skin. Therefore, in the present paper, we have explored the utility of ethosomal systems in the topical treatment of fungal infections. Structure, compositions types, mechanism and techniques of preparation of ethosome also discussed in the paper.

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Preparation of Porous Hydroxyapatite Using Cetyl Trimethyl Ammonium Bromide as Surfactant for the Removal of Lead Ions from Aquatic Solutions

Polymers ◽

10.3390/polym13101617 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1617

Author(s):

Silviu-Adrian Predoi ◽

Carmen Steluta Ciobanu ◽

Mikael Motelica-Heino ◽

Mariana Carmen Chifiriuc ◽

Monica Luminita Badea ◽

...

Keyword(s):

Cetyl Trimethyl Ammonium Bromide ◽

Morphological Changes ◽

Low Cost ◽

Lead Ions ◽

Ammonium Bromide ◽

Porous Hydroxyapatite ◽

X Ray ◽

Composition And Structure ◽

Cetyl Trimethyl Ammonium ◽

Co Precipitation

In the present study, a new low-cost bioceramic nanocomposite based on porous hydroxyapatite (HAp) and cetyl trimethyl ammonium bromide (CTAB) as surfactant was successfully obtained by a simple chemical co-precipitation. The composition and structure of the HAp-CTAB were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), scanning electron microscope (SEM) equipped with an energy dispersive X-ray (EDX) spectrometer, and N2 adsorption/desorption analysis. The capacity of HAp-CTAB nanocomposites to remove the lead ions from aqueous solutions was studied by adsorption batch experiments and proved by Langmuir and Freundlich models. The Pb2+ removal efficiency of HAp-CTAB biocomposite was also confirmed by non-destructive ultrasound studies. The cytotoxicity assays showed that the HAp-CTAB nanocomposites did not induce any significant morphological changes of HeLa cells after 24 h of incubation or other toxic effects. Taken together, our results suggests that the obtained porous HAp-CTAB powder could be used for the decontamination of water polluted with heavy metals, such as Pb2+.

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Mechanisms and Remediation Technologies of Sulfate Removal from Acid Mine Drainage

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.610-613.3252 ◽

2012 ◽

Vol 610-613 ◽

pp. 3252-3256

Author(s):

Mei Qin Chen ◽

Feng Ji Wu

Keyword(s):

Heavy Metals ◽

Acid Mine Drainage ◽

Mine Drainage ◽

Metal Corrosion ◽

Sulfate Ion ◽

High Concentration ◽

Biological Reduction ◽

Acid Mine ◽

Sulfate Removal ◽

Co Precipitation

Acid mine drainage (AMD) has properties of extreme acidification, quantities of sulfate and elevated levels of soluble heavy metals. It was a widespread environmental problem that caused adverse effects to the qualities of ground water and surface water. In the past decades, most of investigations were focused on the heavy metals as their toxicities for human and animals. As another main constitution of AMD, sulfate ion is nontoxic, yet high concentration of sulfate ion can cause many problems such as soil acidification, metal corrosion and health problems. More attention should be paid on the sulfate ion when people focus on the AMD. In the paper, sulfate removal mechanisms include adsorption, precipitation, co-precipitation and biological reduction were analyzed and summarized. Meanwhile, the remediation technologies, especially the applications of them in China were also presented and discussed.

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Lateral distribution and diffusion of plastocyanin in chloroplast thylakoids.

The Journal of Cell Biology ◽

10.1083/jcb.108.4.1397 ◽

1989 ◽

Vol 108 (4) ◽

pp. 1397-1405 ◽

Cited By ~ 51

Author(s):

W Haehnel ◽

R Ratajczak ◽

H Robenek

Keyword(s):

Photosystem I ◽

Laser Flash ◽

Lateral Distribution ◽

High Time Resolution ◽

High Concentration ◽

Long Distance ◽

Kinetic Measurements ◽

Stroma Lamellae ◽

Negative Surface ◽

Negative Surface Charge

The lateral distribution of plastocyanin in the thylakoid lumen of spinach and pea chloroplasts was studied by combining immunocytochemical localization and kinetic measurements of P700+ reduction at high time resolution. In dark-adapted chloroplasts, the concentration of plastocyanin in the photosystem I containing stroma membranes exceeds that in photosystem II containing grana membranes by a factor of about two. Under these conditions, the reduction of P700+ with a halftime of 12 microseconds after a laser flash of saturating intensity indicates that to greater than 95% of total photosystem I a plastocyanin molecule is bound. An analysis of the labeling densities, the length of the different lumenal regions, and the total amounts of plastocyanin and P700 shows that most of the remaining presumable mobile plastocyanin is found in the granal lumen. This distribution of plastocyanin is consistent with a more negative surface charge density in the stromal than in the granal lumen. During illumination the concentration of plastocyanin in grana increases at the expense of that in stroma lamellae, indicating a light-driven diffusion from stroma to grana regions. Our observations provide evidence that a high concentration of plastocyanin in grana in the light favors the lateral electron transport from cytochrome b6/f complexes in appressed grana across the long distance to photosystem I in nonappressed stroma membranes.

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Cationic and Biocompatible Polymer/Lipid Nanoparticles as Immunoadjuvants

Pharmaceutics ◽

10.3390/pharmaceutics13111859 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1859

Author(s):

Yunys Pérez-Betancourt ◽

Péricles Marques Araujo ◽

Bianca de Carvalho Lins Fernandes Távora ◽

Daniele Rodrigues Pereira ◽

Eliana Lima Faquim-Mauro ◽

...

Keyword(s):

Immune Responses ◽

Methyl Methacrylate ◽

Cationic Lipid ◽

Lipid Nanoparticles ◽

Hybrid Nanoparticles ◽

Ammonium Bromide ◽

The Novel ◽

Biocompatible Polymer ◽

Dimethyl Ammonium ◽

Oppositely Charged

Nanostructures have been of paramount importance for developing immunoadjuvants. They must be cationic and non-cytotoxic, easily assembling with usually oppositely charged antigens such as proteins, haptens or nucleic acids for use in vaccines. We obtained optimal hybrid nanoparticles (NPs) from the biocompatible polymer poly(methyl methacrylate) (PMMA) and the cationic lipid dioctadecyl dimethyl ammonium bromide (DODAB) by emulsion polymerization of methyl methacrylate (MMA) in the presence of DODAB. NPs adsorbed ovalbumin (OVA) as a model antigen and we determined their adjuvant properties. Interestingly, they elicited high double immune responses of the cellular and humoral types overcoming the poor biocompatibility of DODAB-based adjuvants of the bilayer type. The results suggested that the novel adjuvant would be possibly of use in a variety of vaccines.

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On how the mechanochemical and co-precipitation synthesis method changes the sensitivity and operating range of the Ba2Mg1-xEuxWO6 optical thermometer

Scientific Reports ◽

10.1038/s41598-021-02309-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Quan T. H. Vu ◽

Bartosz Bondzior ◽

Dagmara Stefańska ◽

Natalia Miniajluk-Gaweł ◽

Maciej J. Winiarski ◽

...

Keyword(s):

Density Functional ◽

Synthesis Method ◽

Double Perovskite ◽

Relative Sensitivity ◽

The Novel ◽

Temperature Detection ◽

The Density Functional Theory ◽

Precision Temperature ◽

Optical Thermometer ◽

Co Precipitation

AbstractThe suitability of Ba2MgWO6 (BMW) double perovskite doped with Eu3+ for the construction of an optical thermometer was tested. It has been shown that by controlling the conditions of BMW synthesis, the sensitivity of the optical thermometer and the useful range of its work can be changed. Pure BMW and doped with Eu3+ samples were prepared using the mechano-chemical and co-precipitation methods. Both the absolute sensitivity and the relative sensitivity in relation to the synthesis route were estimated. The findings proved that the relative sensitivity can be modulated from 1.17%K−1 at 248 K, to 1.5%K−1 at 120 K for the co-precipitation and the mechanochemical samples, respectively. These spectacular results confirm the applicability of the Ba2MgWO6: Eu3+ for the novel luminescent sensors in high-precision temperature detection devices. The density-functional theory was applied to elucidate the origin of the host emission.

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Combined and individual doxorubicin/vancomycin drug loading, release kinetics and apatite formation for the CaO–CuO–P2O5–SiO2–B2O3 mesoporous glasses

RSC Advances ◽

10.1039/c6ra06829d ◽

2016 ◽

Vol 6 (56) ◽

pp. 51046-51056 ◽

Cited By ~ 20

Author(s):

Gurbinder Kaur ◽

O. P. Pandey ◽

K. Singh ◽

Bhupendra Chudasama ◽

V. Kumar

Keyword(s):

Release Kinetics ◽

Drug Loading ◽

Sol Gel ◽

Apatite Formation ◽

The Novel ◽

Gel Technique ◽

Glass Series

The novel mesoporous glass series based on (25 − x)CaO–xCuO–10P2O5–5B2O3–60SiO2 (x = 2.5, 5, 7.5, 10) has been prepared using the sol–gel technique.

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Dual Asymmetric Centrifugation Efficiently Produces a Poloxamer-Based Nanoemulsion Gel for Topical Delivery of Pirfenidone

AAPS PharmSciTech ◽

10.1208/s12249-020-01798-7 ◽

2020 ◽

Vol 21 (7) ◽

Author(s):

Eugene P. Chung ◽

Adrienne R. Wells ◽

Mia Mae Kiamco ◽

Kai P. Leung

Keyword(s):

Biological Activity ◽

Transforming Growth Factor Beta ◽

Transforming Growth Factor ◽

Release Kinetics ◽

Dermal Fibroblasts ◽

Poloxamer 407 ◽

Batch Size ◽

Formulation Development ◽

Relative Standard ◽

Nanoemulsion Gel

Abstract This study used dual asymmetric centrifugation (DAC) to produce a topical vehicle for Pirfenidone (Pf; 5-methyl-1-phenyl-2[1H]-pyridone)—a Food and Drug Administration-approved antifibrotic drug indicated for idiopathic fibrosis treatment. Pf was loaded (8 wt%) in a poloxamer nanoemulsion gel (PNG) formulation consisting of water (47.8 wt%), triacetin (27.6 wt%), poloxamer 407 (P407, 13.8 wt%), polysorbate 80 (1.8 wt%), and benzyl alcohol (0.9 wt%). To our knowledge, poloxamer gels are typically processed with either high-shear methods or temperature regulation and have not been emulsified using DAC. Using a single-step emulsification process, 2 min mixed at 2500 RPM resulted in the lowest Pf loading variability with a relative standard deviation (RSD) of 0.96% for a 1.5 g batch size. Batch sizes of 15 g and 100 g yield higher RSD of 4.18% and 3.05%, respectively, but still in compliance with USP guidelines. Ex vivo permeation in full thickness porcine skin after 24 h showed total Pf permeation of 404.90 ± 67.07 μg/cm2. Tested in vitro on human dermal fibroblasts stimulated with transforming growth factor-beta 1 (TGF-β1), Pf-PNG resulted in a > 2 fold decrease in α-SMA expression over vehicle control demonstrating that formulated Pf retained its biological activity. One-month stability testing at 25°C/60% relative humidity (RH) and 40°C/75% RH showed that % drug content, release kinetics, and biological activity were largely unchanged for both conditions; however, pH decreased from 6.7 to 5.5 (25°C/60% RH) and 4.5 (40°C/75% RH) after 1 month. Overall, these data demonstrate the utility of DAC to rapidly and reproducibly prepare lab-scale batches of emulsified gels for pharmaceutical formulation development.

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Synthesis of Uniform Barium Ferrite Powders by Co-Precipitation Method

Materials Science Forum ◽

10.4028/www.scientific.net/msf.898.1649 ◽

2017 ◽

Vol 898 ◽

pp. 1649-1654 ◽

Cited By ~ 1

Author(s):

Min Chen ◽

Run Hua Fan ◽

Zi Dong Zhang ◽

Yan Sheng Yin ◽

Li Hua Dong

Keyword(s):

Calcination Temperature ◽

Barium Ferrite ◽

Water Bath ◽

Precipitation Method ◽

Ammonium Bromide ◽

Barium Ferrites ◽

Hexagonal Barium Ferrite ◽

Crystallite Sizes ◽

Co Precipitation ◽

Hexadecyltrimethyl Ammonium Bromide

The uniform hexagonal barium ferrite powders were synthesized by co-precipitation method using metal chloride. The effects of the amount of hexadecyltrimethyl ammonium bromide (CTAB), the water bath and calcination temperature on the phase formation, microstructure and density of barium ferrites were systematically investigated. The results showed that the formation of uniform hexagonal barium ferrite powders was significantly influenced by the amount of CTAB and the water bath could lead to the larger grain size and density. The SEM demonstrated that the BaFe12O19 powders had plate-like shape with crystallite sizes varing from 150 to 200 nm. When the amount of CTAB was 0.2g/100ml and the calcination temperature was 850 °C, the barium ferrite powders were uniform which indicated that the amount of surfactant and calcination temperature were very optimum.

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Synthesis of Fe3O4 Nanoparticles Prepared by Various Surfactants and Studying their Characterizations

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.273-276.22 ◽

2008 ◽

Vol 273-276 ◽

pp. 22-27 ◽

Cited By ~ 1

Author(s):

Ali Shokuhfar ◽

S. Alibeigi ◽

Mohammad Reza Vaezi ◽

Sayed Khatiboleslam Sadrnezhaad

Keyword(s):

Fe3o4 Nanoparticles ◽

Cetyl Trimethyl Ammonium Bromide ◽

Precipitation Method ◽

Ammonium Bromide ◽

X Ray Diffraction ◽

Mixed Salt ◽

Magnetite Fe3o4 ◽

Cetyl Trimethyl Ammonium ◽

Size And Morphology ◽

Co Precipitation

Magnetite (Fe3O4) nanoparticles were prepared simply by the reverse co-precipitation method from the solution of ferrous/ferric mixed salt in the presence of cationic surfactant (cetyl trimethyl ammonium bromide, CTAB) and nonionic surfactant (Polyethylene glycol, PEG) in two concentrations. Meanwhile, Fe3O4 nanoparticles without surfactant are also synthesized under the same condition for comparison. In addition via the reverse co-precipitation method, the pH which is an important factor in synthesis of magnetite was controlled at high values easily. The experimental results reveal that addition of surfactants affected on the size and morphology of the nanoparticles based on the X-ray diffraction (XRD) and scanning electron microscope (SEM) characterizations.

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