Background: The transport of CNS acting drugs across blood-brain barrier (BBB) is complex
and guided by the molecular weight, pH, physicochemical and pathological state of the BBB
Methods: In view of this, literatures were assessed for possible conversion of Non-CNS to CNS acting
drugs, whose ability to penetrate CNS can be improved using polymers for biomedical applications.
Results: The findings have shown that compounds with pyridine, pyrrole, carboxamide, pyridone
among others can be converted to CNS acting drugs that can be loaded in specialized carrier polymers
for transportation across BBB. Such carriers are polymers, co-polymers, nanopolymers and polymeric
miscelles that have amine around and pyridine as their hydrophobic site and carboxylic acid as their
hydrophilic site. But balanced hydrophilic/hydrophobic site (amphiphilic) may not increase the transport
rate of the carrier molecule.
Conclusion: Polymeric nanoparticles and copolymers can be used. Examples of such polymers are
poly (lactic-co-glycolic acid), polylactic and poly (propyleneglycol, poly (DI)-lactide, polycaprolactone,
and polyethylene glycol (hydrophilic). They are non-soluble, biodegradable, release the entrapped
drug as they degrade via passive diffusion from polymeric core. Some of their degradation
products can be converted to glycolic acid and lactic acid which are converted to carbon dioxide and
water through the Kreb’s cycle and finally eliminated via urination, perspiration, defecation and expiration.