Solid lipid nanocarriers in drug delivery: characterization and design

ABSTRACT

Introduction: Solid lipid nanoparticles are promising drug carriers for systemic circulations as well as local applications. One of the major challenges for drug delivery is designing nanocarriers for efficient delivery of active substances to the target site and facilitating drug absorption.

Areas covered: In this article, the effects of excipients and particle preparation methods on the properties of solid lipid nanocarriers (SLNCs) and their impact on drug absorption and efficacies related to different administration routes are reviewed and discussed.

Expert opinion: SLNCs have special characteristics, making them attractive as drug delivery systems, for parenteral and oral delivery for systemic effects, or ocular, pulmonary and topical delivery to enhance local treatment efficacy and reducing systemic side effects. Both excipients and fabrication methods are crucial for the function and size of nanoparticles and should be considered simultaneously in designing particles to obtain the optimal drug absorption and efficacy, especially for local treatments. Despite the demonstrated advantages by the preclinical studies, further studies on improved understanding of the interactions of SLNCs with biological tissues of the target site is necessary for efficient designing functional nanoparticles for clinical applications.

Abbreviations: DG: diglycerides; FFA: free fatty acids; GMS: glyceryl monostearate; MG: monoglycerides; NLC: nanostructured lipid carriers; PL: phospholipids; SLM: solid lipid microparticles; SLN: solid lipid nanoparticles; SLNC: solid lipid nanocarriers; TG: triglycerides.

KEYWORDS:

• Functional excipients
• lipid-based drug delivery system
• lipids
• oral drug delivery
• physicochemical characterization
• solid lipid nanocarriers
• systemic circulation
• topical delivery

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties

Reviewer Declarations of Interest

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Article highlights

• Polymorphism of lipid excipients and particle fabrication methods affect drug loading capacity and stability of solid lipid nanocarriers.

• Solid lipid nanocarriers can be used to improve drug bioavailability, but SLN is a better carrier to sustain drug delivery.

• The size and surface properties of solid lipid particles are critical factors affecting drug retention and absorption for both systemic circulations and topical applications.

• Triglycerides with long-chain fatty acids result in sustained drug release in vitro and slower elimination in vivo.

• Solid lipid nanocarriers can modify the biodistributions of drug substances.

Additional information

Funding

This paper was not funded.