Advancing Duodenoscope Reprocessing with Alginate-Coated Calcium Peroxide Nanoparticles

Although significant advances in duodenoscope reprocessing have been introduced since mid-2010s-including enhanced cleaning protocols, disposable distal endcaps, and the introduction of fully single-use duodenoscopes-residual contamination and infection risks remain unresolved. Moreover, repeated reprocessing may cause cumulative damage to the polymer surfaces, elevator mechanisms, and internal channels of the duodenoscopes, making them more susceptible to residual contamination. To minimize the duodenoscope polymer degradation caused by intensive use and reprocessing, new alternatives are urgently needed. In this context, calcium peroxide nanoparticles coated with sodium alginate (CaO₂-Alg NPs), synthesized by our group, were tested for the first time as a disinfectant capable of combating nosocomial pathogens while reducing device deterioration associated with repeated investigations and reprocessing.

The disinfectant properties of the CaO₂-Alg NPs were evaluated under biomimetic conditions using reference bacterial strains commonly associated with nosocomial infections. In addition, the compatibility of the nanoparticles with the polymeric duodenoscope coatings was assessed after simulated intensive use. The external polymer coating was structurally and morphologically characterized by Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), Atomic Force Microscopy (AFM), and Scanning Electron Microscopy (SEM).

The nanoparticles exhibited important antimicrobial activity against the reference bacterial strains Staphylococcus aureus, Escherichia coli, Enterococcus faecalis, and Klebsiella pneumoniae after only 20 min of incubation. Intensive exposure to the CaO₂-Alg NPs did not cause additional structural or morphological damage to the duodenoscope's external polymers and did not alter their anti-adhesive properties.

The CaO₂-Alg NPs appear to be a safe and effective disinfectant for the duodenoscope reprocessing, offering both antimicrobial efficacy and material compatibility.