Albumin nanostructures as advanced drug delivery systems

ABSTRACT

Introduction: One of the biggest impacts that the nanotechnology has made on medicine and biology, has been in the area of drug delivery systems (DDSs). Many drugs suffer from serious problems concerning insolubility, instability in biological environments, poor uptake into cells and tissues, sub-optimal selectivity for targets and unwanted side effects. Nanocarriers can be designed as DDSs to overcome many of these drawbacks. One of the most versatile building blocks to prepare these nanocarriers is the ubiquitous, readily available and inexpensive protein, serum albumin.

Areas covered: This review covers the use of different types of albumin (human, bovine, rat, and chicken egg) to prepare nanoparticle and microparticle-based structures to bind drugs. Various methods have been used to modify the albumin structure. A range of targeting ligands can be attached to the albumin that can be recognized by specific cell receptors that are expressed on target cells or tissues.

Expert opinion: The particular advantages of albumin used in DDSs include ready availability, ease of chemical modification, good biocompatibility, and low immunogenicity. The regulatory approvals that have been received for several albumin-based therapeutic agents suggest that this approach will continue to be successfully explored.

KEYWORDS:

• Human serum albumin
• bovine serum albumin
• ovalbumin
• nanoparticles
• drug delivery systems

Article highlights

• Albumin (from serum or chicken eggs) is the most investigated protein for preparation of protein based drug delivery nanostructures.

• Advantages include ready availability, natural origin, ease of chemical modification, good biocompatibility, biodegradability, and low immunogenicity.

• Albumin has a range of natural molecular binding sites that can be used for drug delivery.

• Albumin nanostructures can solubilize insoluble drugs, reduce toxicity to surrounding normal cells, and protect nucleic acids from degradation.

• Molecular-recognition ligands can be attached to albumin DDSs to allow targeting to specific cells and tissues including cancer.

• Albumin-based DDSs have already received several regulatory approvals and more can be expected.

This box summarizes key points contained in the article.

Declaration of interest

MR Hamblin was supported by US NIH grant R01A1050875. The authors have no other 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 apart from those disclosed.