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Glycyrrhiza glabra L. is a native plant of Central and South-Western Asia that is also diffused in the Mediterranean area and contains several bioactive compounds such as: flavonoids, sterols, triterpene and saponins. Glycyrrhizin, containing glycyrrhizic and glycyrrhizinic acids has anti-inflammatory and antiallergic effects that are similar to corticosteroids. Ammonium glycyrrhizinate is a derivative salt of glycyrrhizic acid with similar anti-inflammatory activity that cannot pass through the skin due to its physicochemical properties and molecular weight. Although several nanoformulations, such as ethosomes, are designed to provide a systemic effect through a topical application, there are different limitations to the distribution inside the blood stream. For this reason, ultradeformable liposomes, or transfersomes, are selected to improve the topical delivery of drugs and allow the distribution of payloads in the blood stream because they pass intact through the stratum corneum epidermis barrier, due to the presence of sodium cholate, aqueous cutaneous gradient, and the rapid penetration of transfersomes by cutaneous tight junctions, thus allowing the systemic delivery of different therapeutic cargo in non-occlusive conditions. The aim of this work was the synthesis and physicochemical characterization of the ammonium glycyrrhizinate-loaded ultradeformable liposomes, the evaluation of drug release and permeation through stratum corneum and epidermis barrier. The in vivo anti-inflammatory effect of ammonium glycyrrhizinate-loaded ultradeformable liposomes was tested on human healthy volunteers. The results demonstrated that the ammonium glycyrrhizinate-loaded ultradeformable liposomes decreased the skin inflammation on the human volunteers and the resulting nanoformulations can be used as a potential topical drug delivery system for anti-inflammatory therapy. ☆ Parts of these results were presented as a poster communication at the Recent Developments in Pharmaceutical Analysis 2019 (RDPA 2019), Chieti, Italy., Competing Interests: Declaration of Competing Interest The authors declare no conflict of interest., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The degree to which liposomes are PEGylated is the feature, which most influences the length of the presence of stealth liposomes in the bloodstream. In order to thoroughly investigate the maximum amount of DSPE-PEG 2000 that can be used to stabilize stealth liposomes, these were synthesized at different concentrations of DSPE-PEG 2000 and their physicochemical properties were investigated by using differential scanning calorimetry (DSC). The kinetics of PEGylation and de-PEGylation were performed by incubating non-stealth liposomes in a DSPE-PEG 2000 suspension at different incubation times, and then analyzing the data using DSC and dynamic light scattering (DLS) techniques. The results demonstrated that DSPE-PEG 2000 was self-assembled in the phospholipid bilayers, thus forming stealth liposomes. The different amounts of DSPE-PEG 2000 in the bilayer triggered a de-PEGylation phenomenon, resulting in mixed nanoaggregates, which derived from the detergent-like properties of the PEGylated phospholipids., (Copyright © 2017 Elsevier B.V. All rights reserved.)

All-trans retinoic acid (ATRA) is an anti-tumor compound, exerting different anti-cancer effects on different types of cancer cells. Unfortunately, retinoids are also characterized by certain side effects following systemic administration, such as the burning of skin and general malaise. The highly variable degree of bioavailability of ATRA plus its tendency to induce its own destruction through metabolic degradation following oral treatment necessitate the development of alternative formulations. The aim of this work is to evaluate the physico-chemical properties of unilamellar, ATRA-containing liposomes and to investigate the cytotoxic activity of this potential nanomedicine on human thyroid carcinoma cells. Liposomes made up of DPPC/Chol/DSPE-mPEG2000 (6:3:1 molar ratio), characterized by a mean diameter of ∼200nm, a polydispersity index of 0.1 and a negative surface charge, were used as ATRA-carriers and their antiproliferative efficacy was investigated in comparison with the free drug on three different human thyroid carcinoma cell lines (PTC-1, B-CPAP, and FRO) through MTT-testing. The liposomes protected the ATRA against photodegradation and increased its antiproliferative properties due to the improvement of its cellular uptake. ATRA-loaded liposomes could be a novel formulation useful for the treatment of anaplastic thyroid carcinoma., (Copyright © 2016 Elsevier B.V. All rights reserved.)

A resveratrol/sulfobutylether-β-cyclodextrin inclusion complex was prepared using the freeze-drying method and characterized in solution through UV-vis spectroscopy, solubility phase studies and Job's plot methods. At the solid state it was characterized using the FTIR-ATR technique. Sulfobutylether-β-cyclodextrin has a high affinity for the drug, and forms an inclusion complex with a 1:1 molar ratio both in solution and as a solid sample. It also has a high stability constant (Kc, 10,114 M(-1)). Complexation strongly increases the water solubility of resveratrol (from 0.03 mg/ml to 1.1 mg/ml, at 25 °C) and positively influences its in vitro anticancer activity which was observed on a human breast cancer cell line (MCF-7). In solid phase, FTIR-ATR revealed itself as being a useful technique in elucidating the complexation mechanism, which it did by emphasizing the functional groups involved in the activation of non-covalent "host-guest" interactions., (Copyright © 2013 Elsevier B.V. All rights reserved.)