Title:Algal Nanosuspensions for Dermal and Oral Delivery
Volume: 8
Issue: 1
Author(s): R. Shegokar*, R. H. Muller*, M. Ismail and S. Gohla
Affiliation:
- Institute of Pharmacy, Department of Pharmaceutics, Biopharmaceutics & NutriCosmetics, Freie Universitat Berlin, Kelchstr. 31, 12169 Berlin,Germany
- Institute of Pharmacy, Department of Pharmaceutics, Biopharmaceutics & NutriCosmetics, Freie Universitat Berlin, Kelchstr. 31, 12169 Berlin,Germany
Keywords:
Algae, N. oculata, Chaetoceros, nanocrystals, dermal application, oral delivery, nutraceutical,
nanonisation, nanosupensions.
Abstract: Background: Algae are widely used for their beneficial properties by food,
cosmetic and nutraceutical industry. For nutraceutical and cosmetic (e.g. oral and dermal)
application, solubility is a key parameter. Algal extracts are available in sticky and completely
dried form and in both cases it is difficult to formulate them due to solubility challenges.
Therefore, attempts were made to produce stable algal nanosuspensions. A nano
algal suspension could increase the biological activity (due to increased saturation solubility
and higher dissolution velocity) and lead to better penetration or absorption profile.
Methods: Dried algae products (N. oculata and Chaetoceros) were obtained from biotechnological
cultivation. The algae were dispersed in Tween 80 or in Poloxamer 188 solutions
and passed through a piston-gap high pressure homogenizer to produce nano algal
suspensions. Production parameters like, number of homogenisation cycles, pressure etc,
were optimised. Nanosuspensions were evaluated for particle size, zeta potential and
crystallinity. Furthermore, nanosuspensions were converted to solid product using lyophilisation
and extrusion-spheronisation technique.
Results: A minimum size of about 226 nm could be achieved after 10 cycles at 1,500 bar.
The aqueous nanosuspensions showed highest, but still insufficient stability at refrigeration
(4 months data), decreasing stability with increasing temperature, especially at 50°C in the
stress storage test and during autoclaving at 121°C. Preservation with Euxyl PE 9010 further
decreased the physical stability of the aqueous algae nanosuspensions. Algae as natural
material undergoes chemical degradation when in contact with water. For long-term preservation
of the size and for chemical stabilization, the algae nanosuspensions were lyophilized.
The algae nanoparticles re-dispersed well in water when using trehalose as cryoprotectant.
The lyophilizate can be filled in capsules. Pellets were produced using the nanosuspensions
as granulation fluid, filled in gelatine capsules for nutraceutical delivery.
Conclusion: Nano-algal suspensions open new perspective for algae products with enhanced
bioavailability and penetration profile. The produced nanosuspensions can be
used for dermal, nutraceutical or cosmetics purposes.
