by Keyword: Dextrin

Vukomanovic, M, Gazvoda, L, Kurtjak, M, Hrescak, J, Jaklic, B, Moya-Anderico, L, Cendra, MD, Torrents, E, (2022). Development of a ternary cyclodextrin-arginine-ciprofloxacin antimicrobial complex with enhanced stability Commun Biol 5, 1234

Designing useful functionalities in clinically validated, old antibiotics holds promise to provide the most economical solution for the global lack of effective antibiotics, as undoubtedly a serious health threat. Here we show that using the surface chemistry of the cyclodextrin (beta CD) cycle and arginine (arg) as a linker, provides more stable ternary antibiotic complex (beta CD-arg-cpx). In contrast to classical less stable inclusion complexes, which only modify antibiotic solubility, here-presented ternary complex is more stable and controls drug release. The components of the complex intensify interactions with bacterial membranes and increase the drug's availability inside bacterial cells, thereby improving its antimicrobial efficacy and safety profile. Multifunctional antibiotics, formulated as drug delivery systems per se, that take the drug to the site of action, maximize its efficacy, and provide optical detectability are envisaged as the future in fighting against infections. Their role as a tool against multiresistant strains remains as interesting challenge open for further research.; Ternary cyclodextrin- arginine- ciprofloxacin complexes show improved stability and increased efficacy against P. aeruginosa in Galleria mellonella worms.

JTD Keywords: Antibiotic-resistance, Beta-cyclodextrin, Dissolution, Drugs, Salts

Perra, M, Manca, ML, Tuberoso, CIG, Caddeo, C, Marongiu, F, Peris, JE, Orru, G, Ibba, A, Fernandez-Busquets, X, Fattouch, S, Bacchetta, G, Manconi, M, (2022). A green and cost-effective approach for the efficient conversion of grape byproducts into innovative delivery systems tailored to ensure intestinal protection and gut microbiota fortification Innovative Food Science & Emerging Technologies 80, 103103

According to circular economy, wine-making by-products represent a fascinating biomass, which can be used for the sustainable exploitation of polyphenols and the development of new nanotechnological health-promoting products. In this study, polyphenols contained in the grape pomace were extracted by maceration with ethanol in an easy and low dissipative way. The obtained extract, rich in malvidin-3-glucoside, quercetin, pro-cyanidin B2 and gallic acid, was incorporated into phospholipid vesicles tailored for intestinal delivery. To improve their performances, vesicles were enriched with gelatine or a maltodextrin (Nutriose (R)), or their com-bination (gelatine-liposomes, nutriosomes and gelatine-nutriosomes). The small (-147 nm) and negatively charged (--50mV) vesicles were stable at different pH values mimicking saliva (6.75), gastric (1.20) and intestinal (7.00) environments. Vesicles effectively protected intestinal cells (Caco-2) from the oxidative stress and promoted the biofilm formation by probiotic bacteria. A preliminary evaluation of the vesicle feasibility at industrial levels was also performed, analysing the economic and energetic costs needed for their production.

JTD Keywords: Adhesion, Antioxidant activity, Caco-2 cells, Dextrin, Grape pomace extract, Lactobacillus-reuteri, Manufacturing costs, Oxidative stress, Ph, Phospholipid vesicles, Polyphenols, Probiotic bacteria, Protein

Silva, N., Riveros, A., Yutronic, N., Lang, E., Chornik, B., Guerrero, S., Samitier, J., Jara, P., Kogan, M. J., (2018). Photothermally controlled methotrexate release system using β-cyclodextrin and gold nanoparticles Nanomaterials 8, (12), 985

The inclusion compound (IC) of cyclodextrin (CD) containing the antitumor drug Methotrexate (MTX) as a guest molecule was obtained to increase the solubility of MTX and decrease its inherent toxic effects in nonspecific cells. The IC was conjugated with gold nanoparticles (AuNPs), obtained by a chemical method, creating a ternary intelligent delivery system for MTX molecules, based on the plasmonic properties of the AuNPs. Irradiation of the ternary system, with a laser wavelength tunable with the corresponding surface plasmon of AuNPs, causes local energy dissipation, producing the controlled release of the guest from CD cavities. Finally, cell viability was evaluated using MTS assays for β-CD/MTX and AuNPs + β-CD/MTX samples, with and without irradiation, against HeLa tumor cells. The irradiated sample of the ternary system AuNPs + β-CD/MTX produced a diminution in cell viability attributed to the photothermal release of MTX.

JTD Keywords: Cyclodextrin, Delivery system, Gold nanoparticles, Inclusion compound, Irradiation, Laser, Methotrexate, Photothermal release

Silva, N., Muñoz, C., Diaz-Marcos, J., Samitier, J., Yutronic, N., Kogan, M. J., Jara, P., (2016). In situ visualization of the local photothermal effect produced on α-cyclodextrin inclusion compound associated with gold nanoparticles Nanoscale Research Letters 11, 180

Evidence of guest migration in α-cyclodextrin-octylamine (α-CD-OA) inclusion compound (IC) generated via plasmonic heating of gold nanoparticles (AuNPs) has been studied. In this report, we demonstrate local effects generated by laser-mediated irradiation of a sample of AuNPs covered with inclusion compounds on surface-derivatized glass under liquid conditions by atomic force microscopy (AFM). Functionalized AuNPs on the glass and covered by the ICs were monitored by recording images by AFM during 5 h of irradiation, and images showed that after irradiation, a drastic decrease in the height of the AuNPs occurred. The absorption spectrum of the irradiated sample showed a hypsochromic shift from 542 to 536 nm, evidence suggesting that much of the population of nanoparticles lost all of the parts of the overlay of ICs due to the plasmonic heat generated by the irradiation. Mass spectrometry matrix-assisted laser desorption/ionization-time-of-flight (MALDI-TOF) performed on a sample containing a collection of drops obtained from the surface of the functionalized glass provided evidence that the irradiation lead to disintegration of the ICs and therefore exit of the octylamine molecule (the guest) from the cyclodextrin cavity (the matrix).

JTD Keywords: Cyclodextrin inclusion compound, Gold nanoparticles, Guest migration, Plasmonic heating