Unification of medicines and excipients: The roles of natural excipients for promoting drug delivery

ABSTRACT

Introduction

Drug delivery systems (DDSs) formed by natural active compounds be instrumental in developing new green excipients and novel DDS from natural active compounds (NACs). ‘Unification of medicines and excipients’(UME), the special inherent nature of the natural active compounds, provides the inspiration and conduction to achieve this goal.

Areas covered

This review summarizes the typical types of NACs from herbal medicine, such as saponins, flavonoids, polysaccharides, etc. that act as excipients and their main application in DDS. The comparison of the drug delivery systems formed by NACs and common materials and the primary formation mechanisms of these NACs are also introduced to provide a deepened understanding of their performance in DDS.

Expert opinion

Many natural bioactive compounds, such as saponins, polysaccharides, etc. have been used in DDS. Diversity of structure and pharmacological effects of NACs turn out the unique advantages in improving the performance of DDSs like targeting ability, adhesion, encapsulation efficiency(EE), etc. and enhancing the bioavailability of loaded drugs.

KEYWORDS:

• Unification of medicines and excipients
• drug delivery system
• natural excipients
• bioactive materials
• natural drug carriers

Article highlights

• This paper systematically demonstrates the ‘unification of medicines and excipients’ role of natural active compounds in improving drug delivery from the aspect of pharmacological activity and excipients effect in drug delivery systems.

• Natural active compounds can form or assist in the formation of various drug delivery systems like micelles, liposomes, nanoparticles, nano-emulsion, etc., and show advantages in improving encapsulation efficacy and bioavailability, enhancing the stability of drug, targeting, and displaying synergistic and toxicity reduction effects.

• The structural characteristics, physical and chemical properties, and pharmacological activity of natural active compounds and loaded drugs play a pivotal role in designing suitable drug delivery systems.

• The introduced forming mechanisms of main natural active compounds-based-drug delivery systems suggest their self-assembly ability and the main driving force is hydrogen bonding and hydrophobic interaction.

• The diversity of natural active compounds in structure and pharmacological activity allows pharmaceutical researchers to have more choices when designing drug delivery systems.

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 disclosures

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

Additional information

Funding

This work was funded by the National Science Foundation of China (82174093) and the Fundamental Research Funds for the Central Universities (BUCM-2019-JYB-JS-016).