the biological membrane (Qian et al. 2012a; Yang and McClements 2013). Such

micelles with comparatively large dimension of nonpolar chains also facilitate

loading of large hydrophobic bioactives and capable to transport these large

hydrphobic molecules across the biological membrane. Some of the oils like

tocopherols have antioxidant property which can be utilized for imparting the

stability to bioactives which are sensitive to oxidation such as carotenoids.

Ethylenediaminetetraacetic acid and ascorbic acid are some other water-soluble

examples of antioxidants which are commonly utilized in nanoemulsions for

providing chemical stability to sensitive bioactives (Qian et al. 2012b). Herbal

bioactives like resveratrol with short half-life in water and susceptible to aqueous

degradation can be formulated as nanoemulsion (Francioso et al. 2014).

Nanoemulsions by encapsulating the bioactive in oil phase not only increase the

shelf life but also slow down the degradation kinetics of resveratrol when

administered orally and hence improve the bioavailability (Davidov-Pardo and

McClements 2015). In conclusion, nanoemulsions as a drug delivery system for

herbal bioactives are the ideal approach for hydrophobic herbal bioactives as it

addresses major challenges of poor water solubility, low permeability, chemical

degradation, and reduced bioaccessibility. Moreover, nanoemulsions are suitable for

oral, topical, and pulmonary route of administration and hence prove its wide

acceptance. Oil solubility, water solubility, miscibility of oil and surfactants, polar-

ity, viscosity, optical clarity, stability, crystal form of bioactive, and partition

coefficient are some of the important formulation considerations that should be

taken into account while formulating nanoemulsions for bioactives.

19.7

Future Prospects

The amalgamation of nanotechnology with herbal bioactives is quintessential in the

current scenario. Nanoemulsions, among all the nanocarrier systems, use industrially

viable and comparatively low-end mechanical instruments for its fabrication; hence,

it is widely accepted and used. The benefits of herbal bioactives are effectively

delivered with the help of nanoemulsions, especially dealing with low-solubility

criteria which most of the natural products have. Nanoemulsions offer great

advantages as they can formulate herbal bioactives and the route of administration

can vary from oral, topical, as well as parenteral. Improved targeting, reduced size,

increased solubility, as well as better bioavailability are some of the major criteria for

a formulation to be efficient. Nanoemulsions inculcate all these features and effec-

tively deliver herbal bioactives without altering their health benefits. With the

upcoming renewal of the use of herbal moieties, it becomes the need of the situation

to effectively deliver the bioactives. This is thus possible with the exploration of the

systematic and effective approach for the formulation of such bioactives.

Nanoemulsions have been widely used in many such cases and have shown tremen-

dous results in nanoresearch. Thus, this collaboration of nanoemulsions with herbal

bioactives holds immense potential for future, providing formulation experts a

pathway to enhance in the field of nanoresearch.

19

Nanoemulsions: A Potential Advanced Nanocarrier Platform for Herbal Drug. . .

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