Nanocrystals: Production, Cellular Drug Delivery, Current and Future Products - Intracellular Delivery: Fundamentals and Applications - page 425

Fig. 6 Mechanism of improved dermal action of rutin nanocrystals ( right ) versus water soluble
rutin glucoside ( left , explanation cf. text)

A similar but less pronounced increase in SPF was observed for the hesperidin
nanocrystals. The important conclusion is, that the nanocrystal technology opens
the perspective to use new classes of molecules, e.g. the plant molecules such as
flavonoids. They could not be used before because of low solubility and limited
penetration of water soluble derivatives. The rutin glucoside shows some effect,
but it needs to be kept in mind that 5% are needed in the formulation, and the
effect being less (hesperidin), or only half of the effect of the nanocrystals (rutin).
The same formulation principle can of course also be applied to pharmaceutical
dermal formulations.

6.2 Pharmaceutical Market

The products on the pharmaceutical market (Table 1 ) exploit the same cell delivery
mechanism I as the dermal products, but using the oral administration route, only
one product is an injectable (Table 1 ). However, the delivery advantage is often
combined with an increased patient convenience. Patients using more patient-friendly
dosage forms show a higher compliance compared to less user friendly formu-
lations. The principles for oral delivery are the same as for dermal. Nanocrystals
provide a higher concentration gradient at the barrier, the barrier skin is replaced by