Niosomal formulation of mefenamic acid for enhanced cancer targeting; preparation, characterization and biodistribution study using radiolabeling technique
Background: This work aimed to prepare niosomal formulations of an anticancer agent [mefenamic acid (MEF)] to enhance its cancer targeting.131I was utilized as a radiolabeling isotope to study the radio-kinetics of MEF niosomes.Methods: niosomal formulations were prepared by the ether injection method and assessed for entrapment efficiency (EE%), zeta potential (ZP), polydispersity index (PDI) and particle size (PS). MEF was labeled with131I by direct electrophilic substitution reaction through optimization of radiolabeling-related parameters. In the radio-kinetic study, the optimal131I-MEF niosomal formula was administered intravenously (I.V.) to solid tumor-bearing mice and compared to I.V.131I-MEF solution as a control.Results: the average PS and ZP values of the optimal formulation were 247.23 ± 2.32 nm and − 28.3 ± 1.21, respectively. The highest131I-MEF labeling yield was 98.7 ± 0.8%. The biodistribution study revealed that the highest tumor uptake of131I-MEF niosomal formula and131I-MEF solution at 60 min post-injection were 2.73 and 1.94% ID/g, respectively.Conclusion: MEF-loaded niosomes could be a hopeful candidate in cancer treatment due to their potent tumor uptake. Such high targeting was attributed to passive targeting of the nanosized niosomes and confirmed by radiokinetic evaluation.