This study aimed to develop a novel topical treatment for Pseudomonas aeruginosa (P. aeruginosa)-induced bacterial keratitis (BK) using silver nanoparticles (Ag NPs), addressing critical limitations of current antibiotics, such as poor ocular penetration and microbial resistance. Ag NPs were synthesized via silver-cysteine conjugation and characterized by UV-Vis spectroscopy, zeta potential, dynamic light scattering (DLS), TEM, XRD, and XPS. In vitro, the nanoparticles exhibited potent antibacterial activity against P. aeruginosa with minimal cytotoxicity toward human corneal epithelial cells (HCECs). Notably, they also retained observable activity against methicillin-resistant Staphylococcus aureus (MRSA), suggesting potential for addressing drug-resistant infections. In a mouse model of P. aeruginosa-induced bacterial keratitis, topical application of the Ag NPs effectively ameliorated the infection without harming healthy ocular tissues, demonstrating favorable biocompatibility and strong therapeutic potential. Overall, Ag NPs represent a promising topical nanotherapeutic for BK, offering enhanced ocular bioavailability, retained activity against drug-resistant strains, and favorable biocompatibility, highlighting their strong potential for clinical translation in ocular infection management.
HuangHXieYZhongJ, et al.Antimicrobial peptides loaded collagen nanosheets with enhanced antibacterial activity, corneal wound healing and M1 macrophage polarization in bacterial keratitis. Composites, Part B Eng2024: 275.
3.
SoibermanUKambhampatiSPWuT, et al.Subconjunctival injectable dendrimer-dexamethasone gel for the treatment of corneal inflammation. Biomaterials2017; 125: 38–53. https://doi.org/10.1016/j.biomaterials.2017.02.016
4.
ThanabalasuriarAScottBNVPeiselerM, et al.Neutrophil extracellular traps confine Pseudomonas aeruginosa ocular biofilms and restrict brain invasion. Cell Host Microbe2019; 25(4): 526. https://doi.org/10.1016/j.chom.2019.02.007
5.
ZhouCPengCShiC, et al.Mitochondria-specific aggregation-induced emission luminogens for selective photodynamic killing of fungi and efficacious treatment of keratitis. ACS Nano2021; 15(7): 12129–12139. https://doi.org/10.1021/acsnano.1c03508
6.
LoucaMWechslerDZ. Protection from steroid-induced glaucoma via iStent inject in a patient with Behcet’s disease. Ophthalmology. Glaucoma2024.
7.
BraungerBMGiesslASchloetzer-SchrehardtU. The blood-ocular barriers and their dysfunction: anatomy, physiology, pathology. Klinische Monatsblatter Fur Augenheilkunde2023; 240(5): 650–661.
8.
ZhaoLSongJDuY, et al.Therapeutic applications of contact lens-based drug delivery systems in ophthalmic diseases. Drug Deliv2023; 30(1): 2219419. https://doi.org/10.1080/10717544.2023.2219419
9.
XieGLinSWuF, et al.Nanomaterial-based ophthalmic drug delivery. Adv Drug Deliv Rev2023; 200: 115004.
10.
RamsayELajunenTBhattacharyaM, et al.Selective drug delivery to the retinal cells: biological barriers and avenues. J Contr Release2023; 361: 1–19. https://doi.org/10.1016/j.jconrel.2023.07.028
11.
KalariaVJSaisivamSAlshishaniA, et al.Design and evaluation of in situ gel eye drops containing nanoparticles of Gemifloxacin Mesylate. Drug Deliv2023; 30(1): 2185180. https://doi.org/10.1080/10717544.2023.2185180
12.
ParthasarathyNThangamRRithisaB, et al.Biomolecule-based engineered nanoparticles for Cancer theranostics. Coord Chem Rev2025; 530: 216489.
13.
BanGChenYLiangY, et al.Exploring the efficacy and constraints of platinum nanoparticles as adjuvant therapy in silicosis management. Drug Deliv2025; 32(1): 2445257. https://doi.org/10.1080/10717544.2024.2445257
14.
HuangYDingXZhuL, et al.Anti-oxidative mesoporous polydopamine-based hypotensive Nano-Eyedrop for improved glaucoma management. Colloids Surf B Biointerfaces2025; 245: 114261.
15.
Aceves-FrancoLASanchez-AguilarOEBarragan-AriasAR, et al.The evolution of triamcinolone acetonide therapeutic use in retinal diseases: from off-label intravitreal injection to advanced Nano-drug delivery systems. Biomedicines2023; 11(7): 1901. https://doi.org/10.3390/biomedicines11071901
16.
YangDHanYWangY, et al.Highly effective corneal permeability of reactive oxygen species-responsive Nano-formulation encapsulated cyclosporine a for dry eye management. Chem Eng J2023; 469: 143968. https://doi.org/10.1016/j.cej.2023.143968
17.
FanCNiQZhuT, et al.Recent progress on antibacterial material of Ag nanoparticle. N Chem Mater2022; 50(9): 229–234.
18.
ArunkumarTCastelinoELakshmiT, et al.Metal-organic frameworks in antibacterial disinfection: a review. ChemBioEng Rev2024; 11(5): e202400006. https://doi.org/10.1002/cben.202400006
19.
TanvirSKaurAAndersonWA. Rapid determination of the antimicrobial properties of surfaces using an enzymatic activity surrogate. Can J Chem Eng2025; 103(3): 1276–1284. https://doi.org/10.1002/cjce.25436
20.
WolffNBialasNLozaK, et al.Increased cytotoxicity of Bimetallic Ultrasmall silver-platinum nanoparticles (2 nm) on cells and bacteria in comparison to silver nanoparticles of the same size. Materials2024; 17(15): 3702. https://doi.org/10.3390/ma17153702
21.
JinJZhangF. Research status of Ag NPs composite antibacterial agent and its carriers. Acta Mater Compos Sin2024; 41(7): 3442–3452.
22.
OndrasovicovaSZigoFFarkasovaZ, et al.Green synthesis of silver nanoparticles and their inhibitory effects on resistant udder pathogens. J Appl Anim Res2025; 53(1): 2462578. https://doi.org/10.1080/09712119.2025.2462578
23.
KabeyaJKNgombeNKMutwalePK, et al.Antimicrobial capping agents on silver nanoparticles made via green method using natural products from banana plant waste. Artif Cell Nanomed Biotechnol2025; 53(1): 29–42. https://doi.org/10.1080/21691401.2025.2462335
24.
HeLXingSZhangW, et al.Multifunctional dynamic chitosan-guar gum nanocomposite hydrogels in infection and diabetic wound healing. Carbohydr Polym2025; 354: 123316. https://doi.org/10.1016/j.carbpol.2025.123316
ThomasSGonsalvesRAJoseJ, et al.Plant-based synthesis, characterization approaches, applications and toxicity of silver nanoparticles: a comprehensive review. J Biotechnol2024; 394: 135–149. https://doi.org/10.1016/j.jbiotec.2024.08.009
27.
ZhangJGaoMGaoW, et al.Functional silver nanoparticles as broad-spectrum antimicrobial agents. New J Chem2022; 46(34): 16387–16393. https://doi.org/10.1039/d2nj02769k
28.
Aguilar-GarayRLara-OrtizLFCampos-LopezM, et al.A comprehensive review of silver and gold nanoparticles as effective antibacterial agents. Pharmaceuticals2024; 17(9): 1134. https://doi.org/10.3390/ph17091134
29.
OnugwuALNwagwuCSOnugwuOS, et al.Nanotechnology based drug delivery systems for the treatment of anterior segment eye diseases. J Contr Release2023; 354: 465–488. https://doi.org/10.1016/j.jconrel.2023.01.018
30.
WangYWangC. Novel eye drop delivery systems: advance on formulation design strategies targeting anterior and posterior segments of the eye. Pharmaceutics2022; 14(6): 1150. https://doi.org/10.3390/pharmaceutics14061150
31.
BaiLXuTZhangW, et al.Abundant geographical divergence of Clostridioides difficile infection in China: a prospective multicenter cross-sectional study. BMC Infect Dis2025; 25(1): 185. https://doi.org/10.1186/s12879-025-10552-y
32.
GumberSKanwarSMazumderK. Properties and antimicrobial activity of wheat-straw nanocellulose-arabinoxylan acetate composite films incorporated with silver nanoparticles. Int J Biol Macromol2023; 246: 125480. https://doi.org/10.1016/j.ijbiomac.2023.125480
33.
ShailajaABruceTFGerardP, et al.Comparison of cell viability assessment and visualization of Aspergillus Niger biofilm with two fluorescent probe staining methods. Biofilm2022; 4: 100090. https://doi.org/10.1016/j.bioflm.2022.100090
34.
LiaSZhangYPanX, et al.Antibacterial activity and mechanism of silver nanoparticles against multidrug-resistant Pseudomonas aeruginosa. Int J Nanomed2019; 14: 1469–1487. https://doi.org/10.2147/IJN.S191340
35.
ZhuYWuSSunY, et al.Bacteria-targeting photodynamic nanoassemblies for efficient treatment of multidrug-resistant biofilm infected Keratitis. Adv Funct Mater2022; 32(14): 2111066. https://doi.org/10.1002/adfm.202111066
36.
MorePRPanditSFilippisAD, et al.Silver nanoparticles: bactericidal and mechanistic approach against drug resistant pathogens. Microorganisms2023; 11(2): 369. https://doi.org/10.3390/microorganisms11020369
37.
MijnendonckxKLeysNMahillonJ, et al.Antimicrobial silver: uses, toxicity and potential for resistance. Biometals2013; 26(4): 609–621. https://doi.org/10.1007/s10534-013-9645-z
38.
KilicBBAltiorsDDDemirbilekM, et al.Comparison between corneal cross-linking, topical antibiotic and combined therapy in experimental bacterial keratitis model. Saudi J Ophthalmol2018; 32(2): 97–104. https://doi.org/10.1016/j.sjopt.2017.10.003
39.
AlmulhimAAlkhalifahMIKalantanH, et al.Bacterial keratitis: clinical features, causative organisms, and outcome during a 13-year study period. Cornea2023; 42(6): 702–707. https://doi.org/10.1097/ICO.0000000000003179
40.
BuckleyAWarrenJHussainR, et al.Synchrotron radiation circular dichroism spectroscopy reveals that gold and silver nanoparticles modify the secondary structure of a lung surfactant protein B analogue. Nanoscale2023; 15(9): 4591–4603. https://doi.org/10.1039/d2nr06107d
41.
DatkhileKDDurgawalePPJagdaleNJ, et al.Biosynthesized silver nanoparticles of Cissus woodrowii inhibit proliferation of cancer cells through induction of apoptosis pathway. Cancer Nanotechnol2024; 15(1): 43. https://doi.org/10.1186/s12645-024-00283-1
42.
TawfeeqATJodouASHamadBS. Comparative assessment of antiproliferative activity of silver nanoparticles on newly established normal embryonic fibroblast cells and immortalized cancer cell lines. Mater Today Commun2025; 44: 111876. https://doi.org/10.1016/j.mtcomm.2025.111876
43.
BurduselA-CGherasimOGrumezescuAM, et al.Biomedical applications of silver nanoparticles: an up-to-date overview. Nanomaterials2018; 8(9). https://doi.org/10.3390/nano8090681
44.
HaidariHGoswamiNBrightR, et al.The interplay between size and valence state on the antibacterial activity of sub-10 nm silver nanoparticles. Nanoscale Adv2019; 1(6): 2365–2371. https://doi.org/10.1039/c9na00017h
45.
LooYYRukayadiYNor-KhaizuraMAR, et al.In vitro antimicrobial activity of green synthesized silver nanoparticles against selected gram-negative foodborne pathogens. Front Microbiol2018; 9: 1555. https://doi.org/10.3389/fmicb.2018.01555
Supplementary Material
Please find the following supplemental material available below.
For Open Access articles published under a Creative Commons License, all supplemental material carries the same license as the article it is associated with.
For non-Open Access articles published, all supplemental material carries a non-exclusive license, and permission requests for re-use of supplemental material or any part of supplemental material shall be sent directly to the copyright owner as specified in the copyright notice associated with the article.
