Nano MOFs as targeted drug delivery agents to combat antibiotic resistant bacterial infections

The drug resistance of bacteria is a significant threat to human
civilization while the action of antibiotics against drug-resistant
bacteria is severely limited due to the hydrophobic nature of drug
molecules, which unquestionably inhibit its permanency for clinical
applications. The antibacterial action of nanomaterials offers major
modalities to combat drug resistance of bacteria. The current work
reports, the use of nano MOFs encapsulating drug molecules to enhance its
antibacterial activity against model drug-resistant free living bacteria
and biofilm of the bacteria. We have attached rifampicin (RF), a
well-documented antituberculosis drug with tremendous pharmacological
significance, into the pore surface of zeolitic imidazolate framework 8
(ZIF8) by a simple synthetic procedure. The synthesized ZIF8 has been
characterized using X-ray diffraction (XRD) method before and after drug
encapsulation. The electron microscopic strategies such as scanning
electron microscope (SEM) and transmission electron microscope (TEM)
methods was performed to characterize the binding between ZIF8 and RF. We
have also performed picosecond resolved fluorescence spectroscopy to
validate the formation of the ZIF8-RF nanohybrids (NHs). The drug release
profile experiment demonstrates that ZIF8-RF depicts pH-responsive drug
delivery and ideal for targeting bacterial disease corresponding to its
inherent acidic nature. Most remarkably, ZIF8-RF gives enhanced
antibacterial activity against methicillin-resistant S. aureus (MRSA)
bacteria and also prompts entire damage of structurally robust bacterial
biofilms. Overall, the present study depicts a detailed physical insight
for manufactured antibiotic-encapsulated NHs presenting tremendous
antimicrobial activity that can be beneficial for manifold practical
applications.