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The growing interest in high-energy emulsification is a result of its scalability, which is important from an industrial perspective and allows for a more reproducible and efficient production of pharmaceutical formulations. The aim of this study was to evaluate the effect of composition, mainly a fixed surfactant/cosurfactant (Smix) ratio, their concentration, and the parameters of high-pressure homogenization (HPH) processing on the quality and stability of ophthalmic fluconazole-loaded nanoemulsions. After a physicochemical analysis of nanoemulsions containing 20% w/w of oil, as optimal conditions for the HPH process, three cycles at a pressure of 1000 bar were established, obtaining formulations with an average droplet diameter size in the range of 80.63–129.68 nm and PDI values below 0.25. While it was expected that an increasing cosurfactant concentration decreased the droplet size, in the case of formulations containing Tween 20 and 10% w/w of cosurfactants, “over-processing” was observed, identified by the droplet size and polydispersity index increase. Consecutively, the selected formulations were evaluated for in vitro drug release in Franz’s cell, antifungal activity, and 30-day stability using NMR spectroscopy. An antifungal activity test showed no significant difference in the antifungal activity between optimal fluconazole-loaded nanoemulsions and a 0.3% aqueous drug solution, but previously, research showed that prepared formulations were characterized by a higher viscosity and satisfactory prolonged release compared to a control. In a 30-day stability study, it was observed that higher HLB values of the used surfactants decreased the stability of the formulations in the following order: Kolliphor EL, Tween 80, Tween 20. The NMR spectra confirmed that Kolliphor EL-based formulations ensured the higher stability of the nanoemulsion composition in comparison to Tween 80 and a better stabilizing effect of propylene glycol as a cosurfactant in comparison to PEG 200. Therefore, the optimization of HPH technology should be focused on the selection of Smix and the Smix:oil ratio in order to prepare stable formulations of high quality.

Targeted anticancer therapies using nanomaterial-based systems enable the delivery of therapeutic substances directly to the cancer cell. Unfortunately, cellular uptake of anticancer drugs is often low and the used active substances are poorly soluble or chemically or physically unstable. Another challenge comes with the limited selectivity of anticancer drugs which translates into their systemic toxicity and the occurrence of many dangerous side effects, significantly hindering the patient's quality of life. The potential solution is to encapsulate the drug in a carrier that could selectively bind to the receptor on the cancer cell. Recently, major advancements can be observed in drug delivery technology using various nanocarriers. This has resulted in an increased demand for materials with stable chemical, physical and mechanical properties. Mesoporous Silica Nanoparticles (MSN) are promising materials with potential application for targeted drug delivery. MSN are porous materials with a size of about 100 nm, high specific surface area and permeability to liquids and gases. Their properties - morphology, particle size, porosity - can be controlled by changing the reactants, their molar ratios or synthesis conditions. All of this makes them ideal candidates as drug carriers. Drug loading may be carried out using an array of methods with physical adsorption from solution being the most commonly used. Controlled surface area and pore size allow to achieve high drug concentration inside the MSN. By attaching specific ligands to the surface of the nanoparticles the carriers can be targeted to a selected receptor located on the membrane of the cancer cell while limiting the effect on neighbouring healthy cells. There is increasing number of reports on the MSN development for biomedical applications. Despite the large number of studies on the biodistribution and biocompatibility of these materials, their behaviour in the body is still not fully understood which significantly limits their development towards clinical applications. This review summarizes and discusses the current state of knowledge about mesoporous silica nanoparticles. The first part of the manuscript discusses the synthesis and functionalization of silica nanoparticles and the influence of various factors on these processes. The second part of the manuscript is summarizes selected examples of MSN as drug delivery systems and discuss their behaviour in the body.

Conventional methods of mass-production of drugs cannot fulfill all the key characteristics that affect the efficacy of pharmacotherapy. Considering that genetic factors and environmental conditions of the individual patient can affect the effectiveness of the therapy formulation of personalized medicines can successfully enhance the quality of life of the patients as well as reduce the risk of side effects. This is particularly important for the pediatric population due to the diversity of the group, especially because of the significant physical and developmental disparities between newborns and teenagers. Following the approval of the first 3D printed tablets by the U.S. Food and Drug Administration in 2015, 3D printing of drug formulations became a promising tool for preparing personalized medicines. Favorable price aspect, ability to manufacture drugs on a small scale, customization of dose, shape, and release profile have given 3D printing a great chance to revolutionize the pharmaceutical market. Fused Deposition Modeling (FDM) uses thermoplastic polymers forced through the printer nozzle at a temperature above melting or softening of the polymer filaments enabling an operator to control both the shape, size, and internal structure of the printed object. On the other hand, the biggest challenge for the implementation of this method in the pharmaceutical environment is the lack of commercially available pharmaceutical-grade filaments. To overcome such an obstacle a Hot-Melt Extrusion process (HME) can be applied providing drug-incorporated filaments of pharmaceutical quality. The findings indicate that FDM 3D printing coupled with HME is a feasible option for manufacturing new drug formulations in a variety of shapes and doses, and that this technique could advance the development of tailored pediatric medicines. This manuscript summarizes and addresses the current state of knowledge, as well as the critical aspects that must be considered, in order to expand the application of FDM 3D printing as a viable manufacturing option for pediatric drugs.

Electrospraying and electrospinning are electrohydrodynamic techniques that are applicable to the production of both capsules and fibers on a micro scale. Electrical forces are applied to the surface of the polymer solution to form a charged jet that stretches towards the collector with simultaneous solvent evaporation, forming beads (microcapsules) or microfibers with polymer coating; the morphology heavily influenced by the stability of the jet. These methods can be used to achieve carriers for biologically active hydrophobic substances, such as oils, fatty acids, and oil-soluble substances due to the fact that they do not require the use of high temperatures or toxic solvents. They enable the encapsulation of liquids in polymeric structures and limit possible oxidative degeneration of sensitive compounds. A potential application for electrosprayed microcapsules and electrospun microfibers is functional food production. Careful selection of polymers of various sources and solvents, as well as process parameters, allows for sealing the oil in the shell. The obtained products show more favorable properties in comparison with oils in the bulk, as well as capsules produced using other common encapsulation techniques. Several properties of the solutions such as their viscosity, surface tension, conductivity, and the degree of polymer chain entanglement directly influence bead or fiber formation. One of the strategies for encapsulation of oils is to disperse it in the polymer solution and use the obtained w/o emulsion as the spraying liquid. Multiple emitters are also used, in the so-called coaxial (or multiaxial) electrospraying/electrospinning. This review discusses the fundamental principles of the electrohydrodynamic processes, as well as various parameters of those techniques (related to solution properties, polymer and solvent selection, the equipment used, and the methods applied to product analysis in terms of its morphology, encapsulation efficiency, and oxidation).

Cocrystals can be defined as crystalline solids composed of at least two compounds in a stoichiometric ratio which interact nonionically. While one of the components is an active pharmaceutical ingredient (API) the term ‘pharmaceutical cocrystal’ could be applied. These are the subject of interest in academic and industrial research as they offer better control over physicochemical, mechanical and pharmacokinetic properties of API while its therapeutic activity remains intact. Commercial success of this approach can be confirmed by the number of marketed pharmaceutical cocrystal drug forms. Despite the range of cocrystallization methods introduced, it is challenging to propose a technique meeting industrial requirements such as scalability or continuousness of the process with respect to ‘green chemistry’ principles being reduction of solvents use. This paper covers the criteria of cocrystallization method selection and presents techniques potentially applicable for large-scale purposes such as Hot Melt Extrusion, Matrix Assisted Cocrystallization and spray congealing with advantages and limitations of those. Within mechanochemical methods of obtaining cocrystals, Matrix Assisted Cocrystallization (MAC) is a promising candidate for industrial-scale use as it is a continuous, one-step, solvent-free technique offering high control over process parameters (e.g. temperature, feed rate, screw speed, screw configuration, extruder type) in order to increase the efficiency of the synthesis and provide high quality product. The addition of polymer facilitates the extrusion and enables conducting the process at lower temperature to prevent degradation of thermolabile substances. Furthermore, cocrystals embedded in polymeric matrix can exhibit the improvement of dissolution rate or compressibility. Additionally, the MAC can be coupled with Process Analytical Technology (PAT) tools to provide real-time data for manufacturing process monitoring and control of product quality.