Nanocarriers for Controlled Release and Target Delivery of Bioactive Compounds
See the new book, edited by Shaba Noore , Shivani Pathania , Pablo Fuciños , Colm P. O’Donnell , Brijesh K. Tiwari.
Description: This brief provides a comprehensive overview of nanocarriers used for nanoencapsulation of bioactive compounds. It includes the basis of encapsulation mechanism, encapsulation efficiency, controlled release, target delivery, and its application in food, nutraceuticals, pharmaceuticals and cosmeceuticals.
Chapter 2
Lipid-Based Nanocarriers
Lipid-based nanocarriers (LNCs) are designed from lipid molecules to encapsulate hydrophobic compounds such as polyphenols, lipophilic vitamins, aromas, and fatty acids. The previous generation of LNCs includes nanoemulsions, nanoliposomes, solid lipid nanoparticles (SLNPs), and nanostructured lipid carriers (NLCs). In recent years, there has been significant progress in LNC engineering, leading to the development of a new generation of LNCs, known as smart-lipid nano-carriers (SLNCs). These nanocarriers are primarily composed of lipids, which are naturally occurring or synthetic molecules that have hydrophobic and hydrophilic regions.
Noore, S., Pathania, S., Fuciños, P., O’Donnell, C.P., Tiwari, B.K. (2024). Lipid-Based Nanocarriers. In: Nanocarriers for Controlled Release and Target Delivery of Bioactive Compounds. SpringerBriefs in Food, Health, and Nutrition. Springer, Cham. https://doi.org/10.1007/978-3-031-57488-7_2
Chapter 3
Protein-Based Nanocarriers
Protein-based nanoencapsulation possesses a higher compound/drug loading capacity than other nanostructures. It improves the absorption and bioavailability of the encapsulated compounds (Abaee et al. 2017; Chen et al. 2006). These nanostructures are prepared by the hydrophobic/hydrophilic interaction of bioactive compounds with the encapsulation matrices. Protein-based nanostructures are responsive to changes in the environment, such as pH change, temperature, enzymatic conditions, and ionic strength, making them suitable candidates for the targeted delivery of bioactive compounds to specified sites (Fang et al. 2014). Several types of proteins, such as whey, zein, and collagens, are used to form these nanocarriers. The release of these encapsulated compounds depends on their interaction with the encapsulation matrix; hydrophilic compounds are dispersed by diffusion, whereas hydrophobic compounds are released through enzymatic degradation of the protein matrix in the gastrointestinal tract (GIT). Additionally, these structures possess several limitations, such as disruption by the presence of protease enzymes in the GIT, making it a challenge to deliver bioactive compounds encapsulated with protein matrices (Bourbon et al. 2011; Donato-Capel et al. 2014). Nevertheless, there are different types of protein-based nanostructures, such as nanoparticles, nanohydrogels, nanotubes, hollow nanoparticles, nanofibrillar aggregates, electrospun nanofibers, and native state proteins as natural nanocarriers cited in the literature (Fig. 3.1) (Mohammadian et al. 2020).
Noore, S., Pathania, S., Fuciños, P., O’Donnell, C.P., Tiwari, B.K. (2024). Protein-Based Nanocarriers. In: Nanocarriers for Controlled Release and Target Delivery of Bioactive Compounds. SpringerBriefs in Food, Health, and Nutrition. Springer, Cham. https://doi.org/10.1007/978-3-031-57488-7_3
Chapter 8
Controlled Release and Target Delivery of Nanoencapsulated Compounds
Based on the application of the encapsulated compounds, its release mechanism is tailored, such as a rapid-release system in local anesthetic lotions and slow release in sunscreens lotions. The release is generally controlled by the structure of the carrier matrices and Ficks’s diffusion, swelling, erosion, etc., mechanism. For example, if the compound is loaded in the outer shell of the nanocarrier, the release profile is rapid such as in the case of bioactive cyclosporine (Muller and Runge 1998). The release is slow if the compound is mixed in carrier matrice in solid-state (molecular dispersion). If the compound is entrapped within the core of the carrier matrix, the release is relatively slow. The matrix of the nanocarriers is controlled by its composition and physicochemical properties, such as solubility in different media. Once the nanosystem interacts with the changing environment, such as a change in pH value, temperature, ionic strength, etc., the structure tends to shift based on the above mentions mechanism.
These mechanisms are broadly categorized into three different classes, including class I ideal fickian diffusion (Brownian transport), class II polymer relaxation-driven transport, class III anomalous behaviour (combination of class I and class II) (Bourbon et al. 2016a). During the preparation of nanostructures, if the concentration of the bioactive compound is soluble in liquid lipid but insoluble in a solid lipid, the compound will precipitate on cooling resulting in an active core coated with some dissolved compounds in lipid. But if the lipid solidifies rapidly, a bioactive shell will be formed. Generally, the prolonged-release is applicable for encapsulation of bioactive compounds as it tends to degrade in GIT due to the lipase-colipase complex. Therefore, the compounds’ release mechanism needs to be understood before fabricating nanostructures for its effective application in food formulations, pharmaceuticals, and nutraceuticals. Several experiments on the release mechanism of encapsulated compounds have been conducted in recent years (Bourbon et al. 2016b, 2003; Ramos et al. 2016). In one of the studies, the effect of GIT condition and release mechanism of curcumin and caffeine was evaluated in protein-based nano-hydrogels coated with chitosan.
The results indicated enhanced stability and bioaccessibility of the bioactive compound in vitro GIT conditions (Bourbon et al. 2018). Stimuli-sensitive nanocarriers tend to modify their physicochemical properties and structure based on the internal or external stimulus actions. Presently, stimuli-based delivery of bioactive compounds with time and site-specific has gained popularity in the nutraceutical and pharmaceutical industries. Several modes of stimuli mechanisms have been developed, such as chemical (change in pH value), biological (wall matrices degradation enzyme), and physical (light, ultrasound, and temperature) for effective controlled target delivery of encapsulated bioactive compounds/drugs. Additionally, the stimulus release is extremely beneficial in the case of disease management, as when a unique stimulus compound is fabricated in nanocarriers, it specifically responds to the pathological trigger of that stimulus (Daglar et al. 2014).
Noore, S., Pathania, S., Fuciños, P., O’Donnell, C.P., Tiwari, B.K. (2024). Controlled Release and Target Delivery of Nanoencapsulated Compounds. In: Nanocarriers for Controlled Release and Target Delivery of Bioactive Compounds. SpringerBriefs in Food, Health, and Nutrition. Springer, Cham. https://doi.org/10.1007/978-3-031-57488-7_8
See the full book here
Shaba Noore , Shivani Pathania , Pablo Fuciños , Colm P. O’Donnell , Brijesh K. Tiwari, Nanocarriers for Controlled Release and Target Delivery of Bioactive Compounds, eBook ISBN 978-3-031-57488-7, Published: 03 May 2024, Publisher Springer Cham, DOI https://doi.org/10.1007/978-3-031-57488-7