Selective Antimicrobial and Antibiofilm Disrupting Properties of Functionalized Diamond Nanoparticles Against Escherichia coli and Staphylococcus aureus

Abstract

Diamond nanoparticles (NDs) have demonstrated great promise as useful materials in a variety of biomedical settings. In this paper, the antimicrobial and antibiofilm activities of variously functionalized NDs against two common bacterial targets Gram‐negative bacterium Escherichia coli and Gram‐positive bacterium Staphylococcus aureus are compared. Hydroxylated (ND‐OH), aminated (ND‐NH2), carboxylated (ND‐COOH), mannose (ND‐Mannose), tri‐thiomannoside (ND‐Man3), or tri‐thiolactoside (ND‐Lac3)‐modified NDs are fabricated and evaluated in the present work. Of these, the mannose‐modified NDs are found to interfere most strongly with the survival of S. aureus, but not to influence the growth of E. coli. In contrast, particles featuring lactosyl units have the opposite effect on S. aureus growth. Sugar‐functionalized NPs reported to display antibacterial effects are rare. Only ND‐COOH particles are seen to have any effect on the growth profile of E. coli, but the effects are moderate. On the other hand, both ND‐NH2 and ND‐COOH are found to inhibit E. coli‐induced biofilm formation at levels comparable to the known E. coli biofilm disruptor, ampicillin (albeit at concentrations of 100 μg mL−1). However, none of the modified particles examined here reveal any significant activity as disruptors of S. aureus‐induced biofilm formation even at the highest concentrations studied.

Unprecedented inhibition of glycosidase-catalyzed substrate hydrolysis by nanodiamond-grafted O-glycosides

“…Diamond nanoparticles (also termed nanodiamonds) are amongst the most promising new carbon-based materials currently being evaluated for biomedical applications. 18,19,25,29,30 In an extension of this work we were curious to establish whether these O-glycoside-conjugated ND were indeed stable to the hydrolytic action of glycosidases and report herein the unprecedented nding that monosaccharide substrates of selected glycosyl hydrolases are not only stable to hydrolysis but moreover behave as competitive, reversible inhibitors of their complementary (matching) glycosidase, simply upon being conjugated in a multivalent fashion to an ND edice. Mannosefunctionalized ND, for example, has been shown to inhibit yeast-agglutination as well as human bladder-cell adherence by E. coli and most notably to be able to disrupt biolm formation.…”

Pillar[n]arenes at the Chemistry‐Biology Interface

“…One key mechanism is for adhesin proteins to interact with monosaccharides found on cell surfaces . To disrupt adhesion, and also to inhibit biofilm formation, compounds containing several sugars, often linked to rigid macrocycles, have been found to be more effective than those with a single sugar . This multivalent approach has been applied to pillar[5]arenes (Figure ), predominantly through click chemistry, to introduce five or ten sugar termini.…”

Affinity of Glycan‐Modified Nanodiamonds towards Lectins and Uropathogenic Escherichia Coli

“…Next to gold, carbon‐based nanomaterials have been investigated as glycan scaffolds as they comply well with several requirements needed such as easy and stable surface functionalization, good dispersibility in aqueous media, and broad availability . Next to fullerene‐based glycoclusters, nanodiamonds (NDs) are emerging as particularly well‐suited for multivalent applications . Amongst the advantages of NDs over other carbon‐based materials is that they are completely inert, optically transparent, biocompatible, have the ability to emit light, and can be functionalized in many ways depending on their intended ultimate application .…”

“…[1,4,6,8,12,13] Next to fullerene-based glycoclusters, [8,13,14] nanodiamonds (NDs) are emerging as particularly well-suited for multivalent applications. [1,4,6,12,15] Amongst the advantages of NDs over other carbon-basedm aterials is that they are completely inert, optically transparent, biocompatible, have the ability to emit light, and can be functionalized in many ways depending on their intended ultimate application. [16][17][18][19][20][21] Although in vivo toxicity of nanoparticles is dependent on specific surface characteristics,N Dp articles did not induce significant cytotoxicity in av ariety of cell lines [22,23] and were used in various biomedical applications.…”