Predicting drug penetration across the blood-brain barrier: comparison of micellar liquid chromatography and immobilized artificial membrane liquid chromatography

Several in vitro methods have been investigated for mimicking drug penetration across the blood-brain barrier (BBB) into the central nervous system (CNS). Both micellar liquid chromatography (MLC) and immobilized artificial membrane (IAM) liquid chromatography were tested in this contribution in order to construct models for BBB transfer prediction. MLC measurements were performed on a C18-column with sodium dodecyl sulfate (SDS), polyoxyethylene (23) lauryl ether (Brij35) or sodium deoxycholate (SDC) as surfactants in the micellar mobile phase. IAM liquid chromatography measurements were performed with a Dulbecco’s phosphate-buffered saline (DPBS) and a certain percentage of methanol as organic modifier in the mobile phase. This study aimed to obtain a high correlation between in vivo and predicted log BB values (= concentration of the drug molecule in the brain to concentration in the blood)

Predicting drug penetration across the blood-brain barrier: comparison of different stationary phases for immobilized artificial membrane liquid chromatography

Several in vitro methods have been tested for their ability to predict drug penetration across the blood-brain barrier into the central nervous system. In this article, the performance of three stationary phases for immobilized artificial membrane (IAM) liquid chromatographic approaches were compared on a set of 49 compounds. IAM liquid chromatography measurements were performed with Dulbecco’s phosphate-buffered saline and methanol as organic modifier in the mobile phase. Transport across the blood-brain barrier (log BB) was predicted using computed descriptor data and the retention factor of all compounds. All data were correlated with experimental log BB values and the relative performance of the approaches was studied. The IAM.PC.DD2 column proved to be the best suited for prediction of log BB values, although all three columns performed very good

Analysis of glycolipids in vegetable lecithin with HPLC-ELSD

Vegetable lecithins play an important role in the microstructural and macroscopic properties of food and cosmetic products. They are widely used as a natural emulsifier. As lecithin is a by-product of the vegetable oil refining industry, its composition is quite variable and rather complex. Therefore, a more complete view on the chemical composition of lecithin would assist in elucidating its functionality. This study focused on the separation and quantification of several glycolipid classes in lecithin, namely (1) digalactosyldiacylglycerol (DGDG) and monogalactosyldiacylglycerol (MGDG), (2) steryl glucosides, (3) esterified steryl glucosides and (4) cerebrosides, using HPLC-ELSD. MGDG was not detected in soy lecithin

Plasma deposition of antibacterial nano-coatings on polymeric materials

Non-woven textile materials with antimicrobial properties are of high demands for applications ranging from medical dressing to everyday cleaning products. A plasma assisted route to engineer antimicrobial nano-composite coatings is proposed. Nano-particles of Ag, Cu and ZnO are tested as antimicrobial agents with average nano-particle size of 20-50 nm. Nanoparticles are incorporated in between two layers of an organosilicon film. The effect of the barrier coating on nano-particles release is determined by XPS. Antibacterial efficiency of the samples against P. aeruginosa ATCC 9027 and S. aureus M u50 bacteria shows that all treated samples exhibit higher antibacterial efficiency against S. aureus. The antibacterial efficiency of AgNPs and CuNPs is above 90% which is practically interesting for medical application while ZnONPs shows lower antibacterial efficiency.This work is supported by the M.Era-Net project IWT 140812 “PlasmaTex”.info:eu-repo/semantics/publishedVersio

Effect of dispersion solvent on the deposition of PVP-Silver nanoparticles onto DBD plasma-treated polyamide 6,6 fabric and Its antimicrobial efficiency

Supplementary Material: https://www.mdpi.com/2079-4991/10/4/607/s1Polyvinylpyrrolidone-coated silver nanoparticles (PVP-AgNPs) dispersed in ethanol, water and water/alginate were used to functionalize untreated and dielectric barrier discharge (DBD) plasma-treated polyamide 6,6 fabric (PA66). The PVP-AgNPs dispersions were deposited onto PA66 by spray and exhaustion methods. The exhaustion method showed a higher amount of deposited AgNPs. Water and water-alginate dispersions presented similar results. Ethanol amphiphilic character showed more affinity to AgNPs and PA66 fabric, allowing better uniform surface distribution of nanoparticles. Antimicrobial effect in E. coli showed good results in all the samples obtained by exhaustion method but using spray method only the DBD plasma treated samples displayed antimicrobial activity (log reduction of 5). Despite the better distribution achieved using ethanol as a solvent, water dispersion samples with DBD plasma treatment displayed better antimicrobial activity against S. aureus bacteria in both exhaustion (log reduction of 1.9) and spray (methods log reduction of 1.6) due to the different oxidation states of PA66 surface interacting with PVP-AgNPs, as demonstrated by X-Ray Photoelectron Spectroscopy (XPS) analysis. Spray method using the water-suspended PVP-AgNPs onto DBD plasma-treated samples is much faster, less agglomerating and uses 10 times less PVP-AgNPs dispersion than the exhaustion method to obtain an antimicrobial effect in both S. aureus and E. coli.This research was funded by FEDER funds through the Operational Competitiveness Program – COMPETE and by National Funds through Fundação para a Ciênciae Tecnologia (FCT) under the project POCI01-0145-FEDER-007136 and UID/CTM/00264/2019. A. Zille also acknowledges financial support of the FCT project PTDC/CTM-TEX/28295/2017 financed by FCT, FEDER and POCI.Isabel Ribeiro (SFRH/BD/137668/2018) acknowledges FCT, Portugal, for its doctoral grant financial support. A. Zille also acknowledges financial support of the FCT project PTDC/CTM-TEX/28295/2017 financed by FCT, FEDER and POCI

Atmospheric pressure plasma deposition of organosilicon thin films by direct current and radio-frequency plasma jets

Thin film deposition with atmospheric pressure plasmas is highly interesting for industrial demands and scientific interests in the field of biomaterials. However, the engineering of high-quality films by high-pressure plasmas with precise control over morphology and surface chemistry still poses a challenge. The two types of atmospheric-pressure plasma depositions of organosilicon films by the direct and indirect injection of hexamethyldisiloxane (HMDSO) precursor into a plasma region were chosen and compared in terms of the films chemical composition and morphology to address this. Although different methods of plasma excitation were used, the deposition of inorganic films with above 98% of SiO2 content was achieved for both cases. The chemical structure of the films was insignificantly dependent on the substrate type. The deposition in the afterglow of the DC discharge resulted in a soft film with high roughness, whereas RF plasma deposition led to a smoother film. In the case of the RF plasma deposition on polymeric materials resulted in films with delamination and cracks formation. Lastly, despite some material limitations, both deposition methods demonstrated significant potential for SiOx thin-films preparation for a variety of bio-related substrates, including glass, ceramics, metals, and polymers.This research was funded by EU H2020 M.Era-Net “PlasmaTex” project. Funding of the Romanian team was insured by the Romanian Ministry of Research and Innovation under the contract 31/2016/UEFISCDI. This work was funded by the Portuguese Foundation for Science and Technology FCT/MCTES (PIDDAC) and co-financed by European funds (FEDER) through the PT2020 program, research project M-ERA-NET/0006/2014. Slovenian team research was funded through the Ministry of Education, Science and Sport and Slovenian Research Agency (ARRS)

Predicting drug penetration across the blood–brain barrier: comparison of micellar liquid chromatography and immobilized artificial membrane liquid chromatography

Several in vitro methods have been tested for their ability to predict drug penetration across the blood–brain barrier (BBB) into the central nervous system (CNS). In this article, the performance of a variety of micellar liquid chromatographic (MLC) methods and immobilized artificial membrane (IAM) liquid chromatographic approaches were compared for a set of 45 solutes. MLC measurements were performed on a C18 column with sodium dodecyl sulfate (SDS), polyoxyethylene (23) lauryl ether (Brij35), or sodium deoxycholate (SDC) as surfactant in the micellar mobile phase. IAM liquid chromatography measurements were performed with Dulbecco’s phosphate-buffered saline (DPBS) and methanol as organic modifier in the mobile phase. The corresponding retention and computed descriptor data for each solute were used for construction of models to predict transport across the blood–brain barrier (log BB). All data were correlated with experimental log BB values and the relative performance of the models was studied. SDS-based models proved most suitable for prediction of log BB values, followed closely by a simplified IAM method, in which it could be observed that extrapolation of retention data to 0 % modifier in the mobile phase was unnecessary