Iranian Journal of Basic Medical Sciences

Iranian Journal of Basic Medical Sciences

Preparation, characterization, and comparison of the release of antibacterial peptide CM11 from PLGA nanoparticles and microparticles

Articles in Press

Document Type : Original Article

Authors
Mohammadmahdi Eshaghi 1
Mehrdad Moosazadeh Moghaddam 2
Marzieh Dehghani 3
Nematollah Jonaidi-Jafari 4
Hamid Hesarikia 5
Ramezan Ali Taheri 1
1 Nanobiotechnology Research Center, New Health Technologies Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran
2 Tissue Engineering and Regenerative Medicine Research Center, New Health Technologies Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran
3 Department of Biophysics, College of Biological Sciences, Tarbiat Modares University, Tehran, Iran
4 Health Management Research Center, Lifestyle and Spiritual Health Research Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran
5 Trauma Research Center, Clinical Sciences Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran
10.22038/ijbms.2026.95430.20573
Abstract
Objective(s): Pseudomonas aeruginosa (P. aeruginosa) is a Gram-negative bacterium capable of causing acute and chronic infections. Treating these infections is increasingly challenging as this bacterium develops antibiotic resistance. Antimicrobial peptides (AMPs) have emerged as promising therapeutic candidates due to their broad-spectrum activity. Cecropin-Melittin-11 (CM11), a cationic AMP, has shown antimicrobial activity against various pathogens. However, the progression of AMPs from preclinical research to clinical application is hindered by enzymatic degradation, short systemic half-life, and cytotoxicity. To overcome these challenges, poly(lactic-co-glycolic acid)(PLGA) particles for peptide delivery have gained attention.
Materials and Methods: CM11-loaded PLGA nanoparticles (NPCM11) and microparticles (MPCM11) were prepared using a double-emulsion solvent evaporation (W1/O/W2) method and characterized for particle size, morphology, encapsulation efficiency, and in vitro release. Their antibacterial activity against planktonic and biofilm-forming P. aeruginosa was evaluated using broth microdilution assay. Their cytocompatibility was evaluated using 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) assay.
Results: Optimum formulations of NPCM11 and MPCM11 were synthesized, exhibiting spherical morphology with average sizes of 281 nm and 7.63 µm, respectively. The encapsulation efficiency (EE%) of NPCM11 and MPCM11 was 63.5% and 60.3%, respectively, while the in vitro CM11 release was 82% and 58%. According to broth microdilution and biofilm inhibition assays, NPCM11 outperformed free CM11 and MPCM11 against planktonic bacteria, whereas both NPCM11 and MPCM11 were superior to free CM11 in biofilm inhibition. MTT assay revealed that NPCM11 and MPCM11 significantly reduced CM11 cytotoxicity.
Conclusion: Overall, NPCM11 and MPCM11 were promising formulations of CM11 for treating P. aeruginosa infections.
Keywords
Antimicrobial peptide
Biofilms
Nanomedicine
Polylactic acid-polyglycolic-acid copolymer
Pseudomonas aeruginosa
Subjects
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Iranian Journal of Basic Medical Sciences

Articles in Press, Accepted Manuscript
Available Online from 22 September 2026