Electrospining: Preparation of fast-disintegrating oral nanofiber mats of astaxanthin by emulsion electrospinning

Background

With the development of modernization, functional foods with health-promoting effects have begun to be considered as an integral part of disease prevention and restorative health care. In recent years, astaxanthin (AST) has shown excellent efficacy in clinical trials for anti-inflammatory, anti-tumor, anti-cancer, anti-obesity, gastroprotective and neuroprotective effects. Its health-promoting properties include quenching singlet oxygen and capturing free radicals. However, poor physicochemical stability, water solubility and bioavailability have become the main limitations of AST in food applications. Therefore, developing efficient food delivery systems to improve the stability, water solubility and bioaccessibility of AST is of practical significance for the development of functional foods.

The main point of this paper

Advantages of electrospinning technology:

As a non-thermal process, electrospinning technology avoids thermal oxidation of heat-sensitive substances. The prepared nanofibers have the advantages of adjustable size and morphology, light weight, and excellent mechanical properties, making them ideal carriers of bioactive ingredients.

Mainstream strategies and their limitations:

Currently, the mainstream strategies for encapsulating bioactive ingredients include co-blended electrospinning and coaxial electrospinning. They have certain advantages in application, but there are still limitations that cannot be ignored, such as the use of organic solvents and incomplete encapsulation will reduce the activity of bioactive ingredients, and the coaxial electrospinning technology is low in efficiency and complex in operation.

Emulsion electrospinning technology:

Emulsion electrospinning technology is considered to be a promising new method. It can prepare core-shell fibers without any organic solvent using only a single-axis spinneret, thereby encapsulating bioactive ingredients.

Application of starch-based stable emulsions:

Starch, as a natural polymer abundant in the food industry, has the advantages of low cost, biodegradability, non-toxicity, and tastelessness, making it an ideal choice for traditional emulsifiers. OSAS (octenyl succinate starch sodium)-based stable emulsion is an ideal precursor for preparing food-grade emulsion electrospun nanofibers for AST delivery system

OSAS/PVA/AST core-shell nanofiber mats:

A green, efficient and scalable method is demonstrated to construct OSAS/polyvinyl alcohol (PVA)/AST core-shell nanofiber mats with starch-based stable emulsions. This method proposes the hypothesis that starch-based emulsion electrospun nanofibers can encapsulate and deliver water-insoluble AST and validates the potential of core-shell nanofibers for oral nutrient delivery

Starch-based nanofiber mats enable green and efficient delivery of astaxanthin via emulsion electrospinning

Demand for green and efficient delivery systems:

The food industry continues to demand the development of green and efficient delivery systems to improve the bioavailability of bioactive ingredients.

Application of emulsion electrospinning technology:

Using emulsion electrospinning technology, AST-loaded starch-based core-shell structured instant nanofibers were prepared without the use of organic solvents.

Preparation process and encapsulation efficiency:

Using OSAS/PVA polymer as an emulsifier, AST-loaded nanoemulsions with high encapsulation efficiency (91.54%) were prepared as precursors for emulsion electrospinning.

Characteristics of nanofibers:

Transmission electron microscopy (TEM) showed that the nanofibers had a core-shell structure with an average diameter of 509.58 nm, and AST was effectively encapsulated in the core layer.

Storage stability and bioaccessibility:

The nanofiber mats had high encapsulation efficiency (85.11%) and good 7-day storage stability, and the amorphous transformation of AST improved its water solubility, bioaccessibility and antioxidant properties.

Summarize

In this study, a green, efficient, low-cost, and non-toxic oral rapid drug delivery system based on OSAS/PVA/AST was obtained by using emulsion electrospinning technology and applied to human dietary supplements. AST was encapsulated in the inner core layer of the OPSA series fibers, completed the amorphous transformation process, and had good solubility in water systems. On the other hand, high levels of OSAS/PVA aggregates helped to obtain core-shell nanofibers with more uniform morphology, lower crystallinity, higher EE, better storage stability, and faster release process, which are required for oral nutrient delivery systems. It is worth noting that the OSAS/PVA/AST emulsion electrospinning system eliminates the potential health hazards of traditional surfactants, avoids the use of organic solvents and thermal oxidation of AST in the traditional encapsulation process, and maintains high antioxidant activity of AST in the fibers. These results indicate that OSAS/PVA/AST emulsion electrospun nanofibers have broad application prospects in the field of oral nutrient delivery. However, poor mechanical properties have been the main limitation for the widespread commercialization of starch-based oral rapid disintegration electrospun nanofiber mats. The preparation of starch-based nanofibers with good mechanical properties is an urgent problem that needs to be solved. Improving the mechanical properties of starch-based nanofiber mats and enhancing their practicality through strategies such as cross-linking technology and adding suitable nanofillers may be the main development direction of starch-based nanofiber mats in the future.