A review of green techniques for the synthesis of size-controlled starch-based nanoparticles and their applications as nanodelivery systems

Background: Due to their small size, fine biological compatibility, and environmental friendliness, starch-based nanoparticles (SNPs) are a promising biomaterial for novel applications in foods, medicines, cosmetics, as well as various fields. SNPs can be utilized as platforms for interaction with bioactive molecules, cells, and tissues in living organisms according to the size of SNPs. As the field matures, it is important to comprehend the challenges associated with nanoparticle commercial development to establish an efficient method to precisely control the particle size. Scope and approach: In the most recent studies, some new green techniques have been tried out to prepare size-controlled SNPs. This paper provides an overview of the most up-to-date information regarding SNPs with controllable particle sizes, including the preparation process, formation mechanism, particle-size control theory, and the structural and physicochemical characteristics. Additionally, applying SNPs as effective nanocarriers for delivering bioactive ingredients or drugs to enhance their absorption and bioavailability will be also summarized in this review. Key findings and conclusions: The SNPs provide new solutions in the development of functional foods, in particular the inclusion of bioactive compounds without affecting the sensory perception of the consumer and improving the uptake of certain components. The size of nano-sized materials is critical for their various properties and applications. The SNPs may serve as effective nanocarriers by delivering bioactive ingredients or drugs to enhance their absorption in the gastrointestinal tract by active endocytosis or to improve bioactivities in body circulation by specific targeting according to their sizes.