In the last years the rapid development of Nucleic Acid Based Drugs (NABDs) to be used in gene therapy has had a great impact in the medical field, holding enormous promise, becoming “the latest generation medicine” with the first ever siRNA-lipid based formulation approved by the United States Food and Drug Administration (FDA) for human use, and currently on the market under the trade name Onpattro™. The growth of such powerful biologic therapeutics has gone hand in hand with the progress in delivery systems technology, which is absolutely required to improve their safety and effectiveness. Lipid carrier systems, particularly liposomes, have been proven to be the most suitable vehicles meeting NABDs requirements in the medical healthcare framework, limiting their toxicity, and ensuring their delivery and expression into the target tissues. In this review, after a description of the several kinds of liposomes structures and formulations used for in vitro or in vivo NABDs delivery, the broad range of siRNA-liposomes production techniques are discussed in the light of the latest technological progresses. Then, the current status of siRNA-lipid delivery systems in clinical trials is addressed, offering an updated overview on the clinical goals and the next challenges of this new class of therapeutics which will soon replace traditional drugs.

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Biocompatible polymer blends, such as alginate blends, have a\ud widespread use in pharmaceutical and medical applications due to their specific\ud features, such as biodegradation, adhesiveness, and thermo- and pH sensitivity\ud and that can be obtained from the mixture composition. In this work, the use of\ud alginate blends was tested in a novel production methodology of therapeutic\ud dosage forms based on polymeric chain reticulation phenomena induced by\ud exposure to bivalent ions. Two kinds of sodium alginate were used to obtain gel\ud films (structured films) in blends with Pluronic F127®. The blends were\ud considered for applications in gel paving of drug-eluting stents. Sodium alginate\ud was also used in shell–core particle production (structured particles) to obtain\ud shell-barrier reducing drug release in the preparative steps (see wash operations).\ud Both structures, films and particles, were obtained using Cu2+ and Ca2+ ions,\ud respectively. Film/shell barrier properties were tested in dissolution experiments\ud using vitamin B12 as an active molecule model. Experimental work demonstrated\ud that the alginate composition is a crucial point in defining reticulated structures

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Nucleic Acid Based Drugs (NABDs) constitute a class of promising and powerful therapeutic new agents with limited side effects, potentially useable against a wide range of diseases, including cancer. Among them, the short interfering RNAs (siRNAs), represent very effective molecules. Despite their in vitro efficacy, the major drawback that limits siRNAs usage consists in a difficult delivery due to their very low stability in physiological fluids, and to their limited membrane-permeability through physiological barriers. On the other hand, the liposomes (lipid bilayers closed in vesicles of various sizes) represent interesting drug delivery systems (DDSs) which can be tailored in order to get the best performance in terms of load, vesicle size and transfection yield. In this work, the current state of study in these two fields, and the connections between them, are briefly summarized.

An innovative, simil-microfluidic, nanoliposome-covering method operating continuously with massive production yield overcoming the disadvantages of conventional methods is proposed.

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The use of liposomes in several fields of biotechnology, as well as in pharmaceutical and food sciences is continuously increasing. Liposomes can be used as carriers for drugs and other active molecules. Among other characteristics, one of the main features relevant to their target applications is the liposome size. The size of liposomes, which is determined during the production process, decreases due to the addition of energy. The energy is used to break the lipid bilayer into smaller pieces, then these pieces close themselves in spherical structures. In this work, the mechanisms of rupture of the lipid bilayer and the formation of spheres were modelled, accounting for how the energy, supplied by ultrasonic radiation, is stored within the layers, as the elastic energy due to the curvature and as the tension energy due to the edge, and to account for the kinetics of the bending phenomenon. An algorithm to solve the model equations was designed and the relative calculation code was written. A dedicated preparation protocol, which involves active periods during which the energy is supplied and passive periods during which the energy supply is set to zero, was defined and applied. The model predictions compare well with the experimental results, by using the energy supply rate and the time constant as fitting parameters. Working with liposomes of different sizes as the starting point of the experiments, the key parameter is the ratio between the energy supply rate and the initial surface area.