The Antimicrobial Properties of Modified Pharmaceutical Bentonite with Zinc and Copper

Abstract

Pharmaceutical grade bentonite, containing a high amount of montmorillonite, enriched with zinc (Zn) or copper (Cu) (ZnBent and CuBent, respectively) was used as the main component for the creation of formulations for cutaneous use and tested for their antimicrobial capacity. Bentonite (Bent) with added phenoxyethanol (PH) as a preservative and unmodified bentonite were used as control groups. The mineralogical composition, structural state, and physical or chemical properties, before and after the modification of the samples, were characterized utilizing X-ray Diffraction Analysis (XRD), Fourier-Transform Infrared Spectroscopy (FTIR) and X-ray Fluorescence (XRF) techniques, and Scanning Electron Microscope-Energy Dispersive Spectroscopy (SEM, SEM-EDS) analyses. In addition, the profile of zinc and copper concentration from two types of surfaces ZnBent and CuBent, and into Phosphate-Buffered Saline (PBS) are discussed. Finally, the formulations in the form of basic pastes were challenged against bacteria, molds, and yeasts, and their performance was evaluated based on the European Pharmacopeia criteria. The Cu-modified bentonite performed excellently against bacteria and yeasts, while the Zn-modified bentonite only showed great results against yeasts. Therefore, Cu-modified bentonite formulations could offer antimicrobial protection without the use of preservatives.

Co-exchanged montmorillonite: a potential antibacterial agent with good antibacterial activity and cytocompatibility

“…18 Besides AgMMT, the antibacterial activities of ZnMMT and CuMMT have also been studied. [19][20][21] All these studies have implied that MMT has a promising application in the antibacterial field. However, most of these ion-exchanged antibacterial MMT do not show good cytocompatibility, 19,22 which limits their application in tissue engineering.…”

Effect of Different Levels of Aqueous Suspension of Bentonite Nanoparticles on Performance and Carcass Characteristics of Broiler Chickens

“…Bentonite is a natural safe clay material, abundant in Jordan with low cost, and convenient for use in animal feed. The antibacterial properties of bentonite have been confirmed (Martsouka et al, 2021). Due to their healing and antimicrobial properties, bentonites are widely used 142 in the pharma, cosmetics, and agriculture industries (Srasra et al, 2020).…”

Romanian Wild-Growing Armoracia rusticana L.—Untargeted Low-Molecular Metabolomic Approach to a Potential Antitumoral Phyto-Carrier System Based on Kaolinite

“…Recent studies have demonstrated that due to its outstanding physico-chemical properties, including small grain size (in the micrometric order), and large specific surface area (of approximately 100 m 2 /g), ensuring high adsorption, swelling, intercalation, and cation-exchange capacity, mineral clays can be used as carrier materials or drug-delivery-system substrates or supports [ 19 , 20 , 21 ].…”

“…In addition, various studies have confirmed the biological properties of clay minerals and reported high chemical stability and the absence of toxicity in vivo. Currently, clay mineral applications are used as active agents or excipients in numerous pharmaceutical and dermato-cosmetic preparations [ 19 , 20 , 21 , 22 , 23 ].…”