Synthesis and Characterization of Nitric Oxide-Releasing Ampicillin as a Potential Strategy for Combatting Bacterial Biofilm Formation

Abstract

Biofilm formation on biomaterial interfaces and the development of antibiotic-resistant bacteria have decreased the effectiveness of traditional antibiotic treatment of infections. In this project, ampicillin, a commonly used antibiotic, was conjugated with S-nitroso-N-acetylpenicillamine (SNAP), an S-nitrosothiol compound (RSNO) used for controlled nitric oxide (NO) release. This novel multifunctional molecule is the first of its kind to provide combined antibiotic and NO treatment of infectious pathogens. Characterization of the molecule included NMR, FTIR, and mass spectrometry. NO release behavior was also measured and compared to pure, unmodified SNAP. When evaluating the antimicrobial efficacy, the synthesized SNAPicillin molecule showed the lowest MIC value against Gram-negative Pseudomonas aeruginosa and Gram-positive methicillin-resistant Staphylococcus aureus compared to ampicillin and SNAP alone. SNAPicillin also displayed enhanced biofilm dispersal and killing of both bacterial strains when treating a 48 h biofilm preformed on a polymer surface. The antibacterial results combined with the biocompatibility of the molecule show great promise for infection prevention and treatment of polymeric interfaces to reduce medical device-related infections.

Antimicrobial efficacy of a nitric oxide-releasing ampicillin conjugate catheter lock solution on clinically-isolated antibiotic-resistant bacteria

“…Conjugation of the NO donor compound S -nitroso- N -acetyl- d -penicillamine (SNAP) to ampicillin was achieved following a previous report with minor deviation. 16 First, a thiolactone derivative (NAPTH) of the acetylated penicillamine (NAP) precursor to SNAP was prepared following previous reports with slight modification. 17,18 In brief, NAP was dissolved in chilled anhydrous pyridine (250 mg mL −1 ) with chilled acetic anhydride (∼3.5 molar equivalent to NAP) added dropwise.…”

“…These results corroborate our prior characterization. 16 SNAPicillin purity was confirmed via NMR and a product of >90% purity was used for further studies.…”

Functionalized MoS2-nanosheets with NIR-Triggered nitric oxide delivery and photothermal activities for synergistic antibacterial and regeneration-promoting therapy

“…To detect the NO release under the physiological environment, we placed RSNO, SNO-CS and SNO-CS@MoS 2 in PBS under natural light at 37 ℃. The results showed that the NO release from the three groups was basically the same, indicating that the slow release of RSNO was mainly related to natural light and room temperature [ 50 , 51 ] (Fig. S8 ).…”

Polyzwitterionic Nanogels for the Controlled and Sustained Delivery of NO and H2S

“…NO is a naturally existing molecule that plays a crucial role in numerous physiological processes. Recent research suggests that the administration of NO at appropriate concentrations can effectively address various human disorders. , The doses of exogenous NO have been observed to strongly inhibit bacterial growth or directly eliminate it. , Gram-positive (Staphylococcus aureus and Staphylococcus epidermidis) and Gram-negative bacteria (Pseudomonas aeruginosa and Escherichia coli), including methicillin-resistant strains of S. aureus, are susceptible to NO broad-spectrum antibacterial action.…”