Abstract: Due to the absence of timely and effective therapies, infections induced by bacterial biofilms have been widely acknowledged as a significant global public health concern. In modern times, aside from surgical intervention (when appropriate), antibiotics are the sole clinical option for treating biofilm-associated infections. However, the rise of drug resistance, as well as the poor therapeutic effects of current treatment regimens in eliminating biofilms highlight the requirement for novel strategies to enhance the accessibility of antibiotics in the “post-antibiotic era”. The current study presents a multifunctional nanoplatform equipped with a “disruption and killing” function to enhance the effectiveness of conventional antibiotics for the eradication of biofilms. Herein, mesoporous silica nanoparticles were employed as carriers to encapsulate the model antibiotic rifampicin (Rif). Subsequently, the nanoparticles were coated with layers of the tannic acid/iron ion (TA/Fe) complex and immobilized with α-amylase. The α-amylase present in the outer layer can degrade the polysaccharides of extracellular polymeric substances (EPS), which in turn disrupts the structural integrity of the biofilms, thus facilitating the entry of the nanoplatform. When exposed to near-infrared (NIR) light, the TA/Fe complex layers can generate heat, which facilitates the release of Rif and increases the bacterial uptake of Rif by damaging the bacterial cell membrane, ultimately resulting in the elimination of bacteria within biofilms. The in vitro experiments demonstrated that this nanoplatform effectively eliminated over 99% of biofilms formed by Staphylococcus aureus and Pseudomonas aeruginosa when exposed to NIR radiation for 10 min. Additionally, in vivo experimental findings further validated the extensive therapeutic efficacy of this nanoplatform against biofilm-infected wounds, accelerating the rate of healing and reducing inflammatory reactions. To summarize, this nanoplatform provides a novel avenue to improve the effectiveness of conventional antibiotics in eradicating bacterial biofilms.

Key words: Atibiofilm, Atibiotics, Potothermal therapy, Etracellular polymeric substances, α-amylase