“Smart” Triiodide Compounds: Does Halogen Bonding Influence Antimicrobial Activities?

Abstract

Antimicrobial agents containing symmetrical triiodides complexes with halogen bonding may release free iodine molecules in a controlled manner. This happens due to interactions with the plasma membrane of microorganisms which lead to changes in the structure of the triiodide anion. To verify this hypothesis, the triiodide complex [Na(12-crown-4)2]I3 was prepared by an optimized one-pot synthesis and tested against 18 clinical isolates, 10 reference strains of pathogens and five antibiotics. The antimicrobial activities of this symmetrical triiodide complex were determined by zone of inhibition plate studies through disc- and agar-well-diffusion methods. The triiodide complex proved to be a broad spectrum microbicidal agent. The biological activities were related to the calculated partition coefficient (octanol/water). The microstructural analysis of SEM and EDS undermined the purity of the triiodide complex. The anionic structure consists of isolated, symmetrical triiodide anions [I-I-I]- with halogen bonding. Computational methods were used to calculate the energy required to release iodine from [I-I-I]- and [I-I···I]-. The halogen bonding in the triiodide ion reduces the antibacterial activities in comparison to the inhibitory actions of pure iodine but increases the long term stability of [Na(12-crown-4)2]I3.

Facile Synthesis of Antimicrobial Aloe Vera-“Smart” Triiodide-PVP Biomaterials

“…Polyiodides contain [I 2k+n ] n− units with stabilizing donor-acceptor interactions of I 2 and iodide ions [ 21 , 22 ]. Iodine is an important microbicide and has many applications in the medical field, as commercial disinfectants, and against biohazards [ 20 , 23 , 24 , 25 , 26 ].…”

“…Complexed compounds with iodine are interesting materials and can be designed in the form of different polyiodides [ 27 , 28 , 29 , 30 , 31 , 32 , 33 ]. Halogen bonding within the polyiodide units are “smart” reservoirs of molecular iodine [ 22 , 27 , 28 , 29 , 30 , 31 , 32 , 33 ]. These reservoirs can be utilized against pathogenic microorganisms through the controlled release of iodine from the complexed halogen-bonded polyiodides [ 22 , 27 , 28 , 29 , 30 , 31 , 32 , 33 ].…”

Prevalence of COVID-19: A Look behind the Scenes from the UAE and India

“…Iodine is an important antimicrobial agents and has many applications in the medical field [71][72][73][74]. Complexed compounds with iodine offer potential agents with controlled release of iodine from polyiodides against pathogenic microorganisms [75][76][77][78][79][80]. The quest for antimicrobial agents should culminate in effective coating agents for masks, gloves, personal protective equipment, surfaces, wound-care products, surgical materials and medical equipment to prevent microbial adsorption.…”

Crystal structure of bis(1,3-phenylenedimethanaminium) bis(triiodide) tetraiodide – water (1/2) , C8H16I5N2O

“…It should not remain unmentioned that polyiodide species may be used as ambipolar zinc electrolytes [12] and further promoted some developments in the field of lithium-iodine redox batteries [13]. There are new considerations that suggest they might have anti-microbial properties [14]. A well established field of research is the synthesis of new polyiodide-containing salts based on organic cations [15].…”