Polymer–Lipid Pharmaceutical Nanocarriers: Innovations by New Formulations and Production Technologies

In this article, a concise overview of the potential of lipid–polymer hybrid nanocarriers was presented. Examples of improved characteristics in terms of functional activity of polymer–lipid nanostructures discussed in the literature were reported. The recent techniques adopted in the production of hybrid nanoparticles were briefly described, underlining the shortcomings still present (limited output volumes, low productivity being bulk techniques, high energy consumption, expensive configuration, long process times) to make the translation of the production of these intelligent particles from the laboratory to the market be sustainable, easy, and fast.

The current scenario on the topic of hybrid nanoparticles reveals a powerful potential of these conceptualized vectors—their uses can range from cancer treatments to nutraceutical, cosmeceutical purposes and diagnostic applications.

From a formulation point of view, research is conducting a careful selection of biocompatible polymer–lipid combinations through more extensive in vivo experiments (about 100 articles have been published on this topic in the last decade—source: Web of Science, Core Collection 2000–2021 query search: “biocompatible polymer–lipid AND in vivo”, last access 19 January 2021).

From a general production point of view, specific impasses in the production of LPHNs are linked to their stability and manipulation. Liquid suspensions are the most diffuse form of the hybrid nanoparticle preparations; otherwise a solid state can be achieved but often after further preparative steps such as, for example, lyophilization. Liquid suspension status often can constitute a limitation for stability and manipulation issues (undesired aggregation and microbiological contamination effects, storage at low or very low temperature, loss of ingredient effectiveness by oxidation phenomena, etc.). To this aim, processes such as concentration (by solvent evaporation unit operation), liquid–solid separation (by mechanical operations), and drying (freeze drying, spray drying—the latter of which is also a main preparative process, as discussed in this work) are currently under investigation. Of course, the features of these post-treatments also must fall in the needs to have sustainable (technologically and in terms of resources) processes for the pharmaceutical industry modernization.