Design, optimization of Niosomal gel capability for solubility and bioavailability enhancement of Kynurenic acid after intranasal administration: In Vitro and In Vivo Evaluation

Kynurenic acid (KNA) could be useful in treating neurological diseases; nevertheless, the fact that it couldn’t penetrate the blood-brain barrier (BBB) limits its neuroprotective efficacy. Research is being conducted on drug delivery devices to transport KNA to the brain. This work set out to make it more soluble, stability, and brain bioavailability of KNA by developing, optimising, and testing a niosomal in situ nasal gel that would cross the blood-brain barrier and overcome its limited permeability. The entrapment efficiency (EE), particle size, and in vitro drug release (CDR) of the resulting niosomes were assessed after preparation using varying concentration of lipid, nonionic surfactant, and cholesterol. To assess the pharmacokinetics of niosomes loaded with KNA in male Wistar rats, a statistical approach was utilised. Measurements such as Cmax, Tmax, t1/2, MRT, AUC, and Ke were evaluated by non-compartmental analysis. The zeta potential of the KNA-niosomes was − 15.64 mV, the CDR was 92.51%, and the EE was 89.52%. The mean particle size of the niosomes was 195.86 ± 4.85 nm. The drug loading capacity was enhanced with the addition of polymers to the KNA. The spherical shape of the niosomes was verified by both conventional microscopy and TEM. The medication and the excipients did not appear to have any chemical interactions. When tested in living organisms, the improved nasal niosomal gel showed a bioavailability that was 2.13 times higher than that of oral medication solutions. Relative to KNA oral suspension, the findings indicated that the KNA-loaded niosomal gel exhibited significantly enhanced relative bioavailability and superior drug permeation across the nasal mucosa.