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The aim of this study was to prepare sodium glycocholate liposomes (SGC-Lip) encapsulating semaglutide (Sml) to improve oral bioavailability and better exert hypoglycemic effect. In this paper, SGC-Lip was prepared by reverse-phase evaporation method with particle size around 140 nm, potential around -27 mV, rounded morphology and better stability. The hypoglycemic and intestinal uptake effects of SGC-Lip and cholesterol-containing liposomes (CH-Lip) were comparatively investigated in rats, and the oral safety of SGC-Lip was examined by cytotoxicity assay. The results indicate that SGC-Lip can achieve a hypoglycemic effect of 40% of the initial value within 12 hours, and the AAC 0-12h is approximately six times that of CH-Lip without sodium glycocholate. The results of the cytotoxicity tests indicate that SGC-Lip has good oral safety. SGC-Lip enhances the absorption of semaglutide in the small intestinal villi via an apical sodium-dependent bile acid transporter (ASBT)-mediated pathway with the highest penetration at the ileal site. In summary, the oral bioavailability of semaglutide can be improved by encapsulating semaglutide in SGC-Lip and utilizing the stabilizing and permeation-promoting effects of SGC on liposomes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The aim of this study was to prepare and evaluate simvastatin (SIM) loaded elastic provesicular systems for effective topical wound management. SIM provesicles were prepared using the non-ionic surfactant Span 40, cholesterol and three edge activators i.e. Span 80, Tween 80 and sodium cholate. The vesicles revealed high SIM encapsulation efficiency ranging from 87.25 to 98.15%, whereas vesicle sizes ranged from 462.3 to 801.5 nm. Vesicle sizes decreased with increasing the concentration of the edge activator. High negative zeta potential values were observed, revealing good stability of the vesicular formulations. The release of SIM from hydrated provesicular carriers was biphasic in nature. The selected SIM provesicular elastic carrier exerted approximately two-fold increase in the amount of SIM permeated through rat skin, compared to the free drug. Evaluation of wound healing activity of the selected provesicular formulation revealed significant reduction in wound size in rats, fourteen days post-wounding. These results were further confirmed by a significant increase in expression of vascular endothelial growth factor and collagen type I compared to the free drug. These results indicate that provesicular carriers could be a promising drug delivery system for encapsulating SIM and enhancing its wound healing efficacy., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Lipoamino acid-based micelles have been developed as delivery vehicles for the hydrophobic drug amphotericin B (AmB). The micellar solubilisation of AmB by a gemini lipoamino acid (LAA) derived from cysteine and its equimolar mixtures with the bile salts sodium cholate (NaC) and sodium deoxycholate (NaDC), as well as the aggregation sate of the drug in the micellar systems, was studied under biomimetic conditions (phosphate buffered-saline, pH 7.4) using UV-vis spectroscopy. Pure surfactant systems and equimolar mixtures were characterized by tensiometry and important parameters were determined, such as critical micelle concentration (CMC), surface tension at the CMC (γCMC), maximum surface excess concentration (Γmax), and minimum area occupied per molecule at the water/air interface (Amin). Rheological behaviour from viscosity measurements at different shear rates was also addressed. Solubilisation capacity was quantified in terms of molar solubilisation ratio (χ), micelle-water partition coefficient (KM) and Gibbs energy of solubilisation (ΔGs°). Formulations of AmB in micellar media were compared in terms of drug loading, encapsulation efficiency, aggregation state of AmB and in vitro antifungal activity against Candida albicans. The LAA-containing micellar systems solubilise AmB in its monomeric and less toxic form and exhibit in vitro antifungal activity comparable to that of the commercial formulation Fungizone., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Ciprofloxacin is a synthetic fluoroquinolone antibiotic that has been used for systemic treatment of otitis media in adults. It was approved for topical treatment of otorrhea in children with tympanostomy tubes. The aim of this work was to enhance the local non-invasive delivery of ciprofloxacin to the middle ear across an intact tympanic membrane (TM) in an attempt to treat acute otitis media (AOM) ototopically. In order to achieve this goal, ciprofloxacin nano-transfersomal vesicles were prepared by thin film hydration (TFH) technique, using several edge activators (EAs) of varying hydrophilic-lipophilic balance (HLB) values. A full factorial design was employed for the optimization of formulation variables using Design-Expert(®) software. The optimal formulation was subjected to stability testing, ex-vivo permeation studies (through ear skin and TM of rabbits), and in-vivo evaluation. Results revealed that the optimal formulation (composed of phospholipid and sodium cholate as an EA at a molar ratio of 5:1) exhibited enhanced ex-vivo drug flux through ear skin and TM when compared with the commercial product (Ciprocin(®) drops). It demonstrated a greater extent of in-vivo drug deposition in the TM of albino rabbits relative to Ciprocin(®). Consequently, transfersomes could be promising for the non-invasive trans-tympanic delivery of ciprofloxacin., (Copyright © 2014 Elsevier B.V. All rights reserved.)

A method has been developed for the synthesis of intercalated layered double hydroxide (LDH) nanohybrids of the charge-neutral and poorly water-soluble anticancer drug camptothecin (CPT) using a coassembly route. For this route, CPT molecules were initially incorporated into the micelles of a biocompatible surfactant, such as sodium cholate (SCh) or sodium deoxycholate (SDC). The resulting negatively charged CPT-loaded micelles and the positively charged LDH nanosheets were then coassembled together into the CPT intercalated LDH nanohybrids. The resulting nanohybrids were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) and elemental analyses. The results revealed that the loading of CPT in the nanohybrids could reach as high as 13%, indicating that this route could be used to achieve the effective intercalation of charge-neutral and poorly water-soluble drugs into the LDH gallery. The in vitro release of CPT from the nanohybrids was examined, and the results showed that the release was a diffusion-controlled process and that the diffusion process through the LDH particles was the rate-limiting step. The parabolic diffusion equation effectively described the kinetic process associated with the release of CPT from the nanohybrids., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Growing attention has been given to the potential of pulmonary route as an alternative for non-invasive systemic delivery of therapeutic agents. In this study, novel nebulizer-compatible solid lipid nanoparticles (SLNs) for pulmonary drug delivery of insulin were developed by reverse micelle-double emulsion method. The influences of the amount of sodium cholate (SC) and soybean phosphatidylcholine (SPC) on the deposition properties of the nanoparticles were investigated. Under optimal conditions, the entrapment delivery (ED), respirable fraction (RF) and nebulization efficiency (NE) of SLNs could reach 96.53, 82.11 and 63.28%, respectively, and Ins-SLNs remained stable during nebulization. Fasting plasma glucose level was reduced to 39.41% and insulin level was increased to approximately 170 microIU/ml 4h after pulmonary administration of 20 IU/kg Ins-SLNs. A pharmacological bioavailability of 24.33% and a relative bioavailability of 22.33% were obtained using subcutaneous injection as a reference. Incorporating fluorescent-labelled insulin into SLNs, we found that the SLNs were effectively and homogeneously distributed in the lung alveoli. These findings suggested that SLNs could be used as a potential carrier for pulmonary delivery of insulin by improving both in vitro and in vivo stability as well as prolonging hypoglycemic effect, which inevitably resulted in enhanced bioavailability.

Solid lipid nanoparticles (SLNs) loaded with insulin-mixed micelles (Ins-MMs) were prepared by a novel reverse micelle-double emulsion method, in which sodium cholate (SC) and soybean phosphatidylcholine (SPC) were employed to improve the liposolubility of insulin, and the mixture of stearic acid and palmitic acid were employed to prepare insulin loaded solid lipid nanoparticles (Ins-MM-SLNs). Some of the formulation parameters were optimized to obtain high quality nanoparticles. The particle size and zeta potential measured by photon correlation spectroscopy (PCS) were 114.7+/-4.68 nm and -51.36+/-2.04 mV, respectively. Nanospheres observed by transmission electron microscopy (TEM) and scanning electron microscopy (SEM) showed extremely spherical shape. The entrapment efficiency (EE%) and drug loading capacity (DL%) determined with high performance liquid chromatogram (HPLC) by modified ultracentrifuge method were 97.78+/-0.37% and 18.92+/-0.07%, respectively. Differential scanning calorimetry (DSC) of Ins-MM-SLNs indicated no tendency of recrystallisation. The core-shell drug loading pattern of the SLNs was confirmed by fluorescence spectra and polyacrylamide gel electrophoresis (PAGE) which also proved the integrity of insulin after being incorporated into lipid carrier. The drug release behavior was studied by in situ and externally sink method and the release pattern of drug was found to follow Weibull and Higuchi equations. Results of stability evaluation showed a relatively long-term stability after storage at 4 degrees C for 6 months. In conclusion, SLNs with small particle size, excellent physical stability, high entrapment efficiency, good loading capacity for protein drug can be produced by this novel reverse micelle-double emulsion method in present study.

Four pharmaceutically active molecules, each representing a different class of antibiotic, were intercalated in layered double hydroxides. Two of them, gramicidin and amphotericin B, are hydrophobic, surface active drugs that were incorporated in artificial membranes formed in the interlayer of the inorganic host. The other two, ampicillin and nalidixic acid, are water soluble, commonly used antibiotics that were directly intercalated by using simple ion exchange reactions. The synthetic nanohybrid materials were characterized by various methods, as X-ray diffraction, infrared spectroscopy and ultraviolet-visible spectroscopy that verified the successful intercalation of the antibiotics and provided information regarding the interlayer structure of the nanohybrids. The reversible interaction of the antibiotic molecules with the inorganic host leads to release of the active drugs under the appropriate conditions. The release studies showed that the synthetic nanohybrids can successfully serve as controlled release systems for different kinds of antibiotics.

Polysaccharide-coated liposomes have been studied for their potential use for peptide drug delivery by the oral route because they are able to minimize the disruptive influences on peptide drugs of gastrointestinal fluids. The aim of this work was to synthesize and characterize a modified polysaccharide, O-palmitoylscleroglucan (PSCG), and to coat unilamellar liposomes for oral delivery of peptide drugs. To better evaluate the coating efficiency of PSCG, also scleroglucan (SCG)-coated liposomes were prepared. We studied the surface modification of liposomes and the SCG- and PSCG-coated liposomes were characterized in terms of size, shape, zeta potential, influence of polymer coating on bilayer fluidity, stability in serum, in simulated gastric and intestinal fluids and against sodium cholate and pancreatin. Leuprolide, a synthetic superpotent agonist of luteinizing hormone releasing hormone (LHRH) receptor, was chosen as a model peptide drug. After polymer coating the vesicle dimensions increased and the zeta potential shifted to less negative values. These results indicate that both SCG- and PSCG-coated liposomes surface and DSC results showed that PSCG was anchored on the liposomal surface. The stability of coated-liposomes in SGF, sodium cholate solution and pancreatin solution was increased. From this preliminary in vitro studies, it seems that PSCG-coated liposomes could be considered as a potential carrier for oral administration.

The prodrug 5'-octanoyl-CPA (Oct-CPA) of the antiischemic N6-cyclopentyladenosine (CPA) has been encapsulated by nanoprecipitation in poly(lactic acid) nanoparticles, which have been recovered by gel-filtration, ultra-centrifugation or dialysis. We have analysed how different surfactants and purification methods can influence the nanoparticle characteristics. The particle sizes have been obtained by scanning electron microscope, whereas a SdFFF system was employed to detect their distributions. The Oct-CPA release from nanoparticles and stabilities in human blood of free and encapsulated prodrug have been analysed by HPLC techniques. The effects of nanoparticles on CPA interaction toward adenosine A1 receptor (its action site) have been analysed using radiolabelled drugs. The smallest nanoparticles and the best degree of homogeneity have been obtained using sodium cholate; the best recovery has been achieved by dialysis, whereas gel-filtration and ultra-centrifugation have induced the greatest removal of surfactants. The release of Oct-CPA was better controlled from the nanoparticles obtained using Pluronic F68 and purified by gel-filtration or ultra-centrifugation. Similarly, these nanoparticles better increased the stability of the prodrug in human blood. In particular, the nanoparticles purified by ultra-centrifugation induced a strong stability to a fraction of the encapsulated Oct-CPA. Any interference by unloaded nanoparticles has been registered for CPA-adenosine A1 receptor interaction.

The aims of this study were to refine ultradeformable liposomes for oestradiol skin delivery and to evaluate Span 80 and Tween 80 as edge activators compared with sodium cholate. Vesicles containing phosphatidylcholine (PC) mixed with edge activators and oestradiol were prepared. Entrapment efficiency and vesicle size were determined. Interactions between activators and vesicles were investigated using differential scanning calorimetry. Transepidermal permeation of oestradiol from vesicles was studied compared to saturated aqueous control in vitro. The maximum flux (J(max)) and its time (T(max)) were calculated from the flux curves and skin deposition was assessed. The compositions of refined formulations were predicted, liposomes prepared, and tested against control. Entrapment efficiency depended on PC concentration with some contribution from sodium cholate and Tween 80. Vesicle sizes ranged from 124 to 135 nm. Edge activators interacted with lipid bilayers and disrupted packing. The refined edge activator concentrations in PC vesicles were 14.0, 13.3 and 15.5% w/w for sodium cholate, Span 80 and Tween 80, respectively; they increased J(max) by 18, 16 and 15-fold and skin deposition by 8, 7 and 8-fold compared with control. Ultradeformable vesicles thus improved skin delivery of oestradiol compared to control and Span 80 and Tween 80 were equivalent to sodium cholate as edge-activators.