l-Cysteine conjugated poly l-lactide nanoparticles containing 5-fluorouracil: formulation, characterization, release and uptake by tissues in vivo

Abstract

Context: Targeted delivery of drugs is still a therapeutic challenge and numerous methods have been reported for the same.

Objective: In this study, emphasis was placed on developing nanoparticles loaded with 5-fluorouracil (FU) and modifying the surface of the nanoparticles by conjugation with amino acid, to improve the distribution of 5-FU in the lungs.

Methods: An emulsion solvent evaporation technique was used to formulate nanoparticles of FU using Poly l-lactide and Pluronic F-68. The nanoparticles were conjugated with l-Cysteine using EDC as the activator of COOH group and were evaluated for product yield, particle size, surface morphology, amount of conjugation by Ellman’s method and in vitro drug release study.

Results and conclusion: The results indicated 60–65% yield with an average particle size of 242.7 ± 37.11 nm for the cysteine conjugated nanoparticle (CNP) formulation and more than 70% conjugation of cysteine. The cumulative percentage of drug released over a period of 24 h was found to be 58%. An increase in distribution of the delivery system in lungs (11.4% ID after 1 h) in mice was found indicating the role of l-Cysteine in the transport mechanism to the lungs. In vivo kinetic studies in rats revealed higher circulation time of CNP as compared to pure FU solution. The study helps in designing a colloidal delivery system for increased distribution of drugs to the lungs and may be helpful in delivery of drugs in conditions like non-small cell lung carcinomas.

• l-Cysteine
• 5-fluorouracil
• mercaptalbumin
• nanoparticles
• non-small cell lung cancer
• Pluronic F 68

Acknowledgements

The authors would like to thank Dr Anil Kumar Mishra, Scientist F, INMAS, New Delhi, India for providing the facilities for performing radiolabeling studies. One of the authors Mr Brijeshkunvar Mishra would also like thank Director, Technocrats Institute of Technology (Pharmacy), Bhopal, India for providing the facilities for in vitro cytotoxicity studies.

Declaration of interest

The authors report no declarations of interest.