Lipid-based Nanocarriers for Drug Delivery and Targeting: a Patent Survey of Methods of Production and Characterization

Abstract

Among the colloidal vectors proposed for the controlled delivery and targeting of drugs and other biologically active compounds, lipid-based nanocarriers are acquiring an increasing role due to a number of peculiar technological and physical features. Solid lipid nanoparticles, lipid nanocapsules, nanostructured lipid carriers, and drug-lipid conjugates are all examples of how it can be possible to combine the properties of the more acknowledged liposomal systems, such as biocompatibility and biodegradability, with the stability and compositional flexibility, distinctive of polymeric nanosystems. This article introduces recent patents, filed in years 2007-2013, that deal with novel or amended methods of production of the various types of lipid-based nanocarriers. Although a significant gap still remains between basic research and patenting activity in this field, many of the proposed methods can attain an industrial value. Furthermore, the critical analysis of these patents further supports the position that a general revision of patenting systems at an international level would be necessary for nanosized pharmaceutical systems.

Lipid Nano- and Microparticles: An Overview of Patent-Related Research

“…These data highlight a general trend in the patenting activity of lipid particles; in the 1990s, the scientific community, especially in Europe, showed increased interest in innovative preparation techniques for lipid nanoparticles, while, from the beginning of the new millennium, patenting activity shifted mainly towards drug delivery applications, and researchers from Emerging Countries became progressively more involved. Some small and medium industries (SMEs) and spin-off companies that dedicate their core business to lipid nanoparticles have also arisen: Italian Nanovector Srl, Russian Nanosystem Ltd., German PharmaSol GmbH, Spanish Lipotec SA, Indian Transgene Biotek Ltd., and Korean AmorePacific Corp are some examples [189,190]. In fact, SMEs can be seen to be the main driving force for innovation in this field, even more so than large companies [182].…”

“…However, there is a large gap between the number of literature articles and patents despite the increasing interest in lipid carriers [189,190]. Furthermore, an evaluation of the status of existing patents reveals that only a few have reached the granted status, while the remainder are still classified as applications.…”

Development of Solid Lipid Nanoparticles by Cold Dilution of Microemulsions: Curcumin Loading, Preliminary In Vitro Studies, and Biodistribution

“…Moreover, SLNs represent an alternative option to the traditional colloidal drug delivery systems, such as emulsions, liposomes, and polymeric micro and nanoparticles, because the problems related to industrial production scale-up, sterilization, and mid-term storage are reduced [11]. SLNs are composed of a solid lipid matrix often covered with a surfactant or phospholipid layer; indeed, their main advantage in drug delivery is related to their nanometric size (below 1000 nm) and to the presence of physiological or biocompatible lipids or lipid molecules, solid at room conditions, with a history of safe use in therapy.…”

A Method for Efficient Loading of Ciprofloxacin Hydrochloride in Cationic Solid Lipid Nanoparticles: Formulation and Microbiological Evaluation

“…The main advantages of SLN versus other colloidal drug carriers include the possibility of achieving a controlled drug release, while increasing the physicochemical stability of loaded drugs, both lipophilic and hydrophilic compounds [ 20 ]. Additionally, problems related to industrial production scale-up, sterilization, and mid-term storage are reduced with respect to liposomes and polymeric nanocarriers [ 21 , 22 , 23 , 24 ].…”