Potential of particle size less than 15 nm via olfactory region for direct brain delivery via intranasal route

Abstract

Central nervous system-related disorders are very difficult to manage with conventional therapeutics because of the selective and herculean nature of the blood-brain barrier which does not allow easy penetration of drug molecules into the brain. As a result, the efficacy of administered molecule is reduced manifold times, and difficult to ascertain the condition of the patient. An alternative route like the nose to the brain is subjectively being explored to enhance the brain's delivery. Recently various published testimonies have proved the nose to the brain can be an alternative route of administration for effective delivery to the brain. This review majorly highlights the hurdles in the delivery of the nasal route and explores the new areas available for delivery via the concept of particle size below 15 nm, which might penetrate the olfactory bulb via the paracellular spaces present in the olfactory epithelium, which starts from the brain and terminates in the nose. The success of this review might reveal new insights into drug delivery for brain targeting and the necessary delivery mechanism.