Meropenem incorporated nanoflowers as nano antibiotics: A promising strategy for combating antimicrobial resistance and biofilm-associated infections

• AMR is a global health crisis, worsened by biofilm-associated bacterial resistance. • Meropenem-based nanoflowers (mNFs) were synthesized and fully characterized. • mNFs showed effective inhibition of P. aeruginosa , K. pneumoniae , and S. aureus . • mNFs caused significant cell membrane disruption and reduced bacterial viability . • mNFs achieved up to 84.54 % biofilm inhibition, offering potential against AMR . Antimicrobial resistance (AMR) poses a significant global health threat, with biofilm formation playing a critical role in reducing antibiotic efficacy. This study aims to develop an innovative nanomaterial-based approach to combat AMR by synthesizing meropenem-based nanoflowers (mNFs) and evaluating their antibacterial and antibiofilm activities. The mNFs were synthesized via a simple self-assembly method and extensively characterized. Field Emission Scanning Electron Microscopy (FESEM) and Transmission Electron Microscopy (TEM) confirmed their distinct flower-like morphology with sizes ranging from 200–450 nm. Energy-Dispersive X-ray Spectroscopy (EDX) verified elemental composition, while X-Ray Diffraction (XRD) analysis revealed their crystalline structure. Dynamic Light Scattering (DLS) showed a hydrodynamic size of ∼300 nm, and UV–Vis spectroscopy confirmed characteristic meropenem peaks, indicating successful nanoflower formation. The mNFs exhibited potent antibacterial activity against Pseudomonas aeruginosa PAO1, Staphylococcus aureus , and Klebsiella pneumoniae , with MIC50 values of 0.4 mg/mL for P. aeruginosa and K. pneumoniae , and 0.6 mg/mL for S. aureus . A significant reduction in colony-forming units (CFU/mL) was observed in P. aeruginosa cultures treated with mNFs compared to free meropenem. Confocal microscopy showed an increased ratio of dead cells post-treatment, while TEM images revealed substantial cell membrane disruption. Cell permeability assays further confirmed compromised bacterial membranes. Importantly, mNFs demonstrated robust anti-biofilm activity, achieving up to 84.54 % biofilm inhibition against P. aeruginosa PAO1 at 0.5 mg/mL. Additionally, the production of pyocyanin, a key virulence factor, was significantly reduced following treatment. In conclusion, this study introduces meropenem-based nanoflowers as a novel and effective strategy for tackling biofilm-associated infections and antimicrobial resistance. The combination of enhanced antibacterial efficacy, biofilm disruption, and virulence suppression positions mNFs as a promising therapeutic candidate for combating multidrug-resistant pathogens.