Interaction Of Chlorhexidine Research Articles

Qualitative and quantitative analysis of precipitate formation following interaction of chlorhexidine with sodium hypochlorite, neem, and tulsi.

Introduction:The interaction between chlorhexidine (CHX) and sodium hypochlorite (NaOCl) yields a thick precipitate capable of occluding dentinal tubules. Previous studies are unclear as to the above-mentioned precipitate contains para-chloroaniline (PCA) or not. PCA is a known toxic and carcinogenic compound which may lead to methemoglobinemia in humans.Aim:This study aims to evaluate the precipitate formed on combination of different irrigants, weigh the amount of precipitate formed and to analyze the precipitate for PCA by using thin layer chromatography (TLC), high performance liquid chromatography (HPLC), column chromatography (CC), electron spray ionization mass spectrometry (ESI-MS), Ultraviolet (UV), and nuclear magnetic resonance (1H-NMR and C-13 NMR).Materials and Methods:Four different irrigants namely 2% CHX gluconate, 3% NaOCl, 5% neem and 5% tulsi were taken in different test tubes. Group 1, 2 and 3 included 1 ml 2% CHX combined with 1 ml each of 3% NaOCl, 5% neem and 5% tulsi. Group 4 and 5 comprised of 1 ml 3% NaOCl in combination with 1 ml 5% each of neem and tulsi. Finally, group 6 constituted 1 ml 5% neem mixed with 1 ml 5% tulsi. Each group was observed for 2 min for the formation of any precipitate, and the formed precipitate was weighed and analyzed using 1H-NMR and C-13 NMR, TLC, CC, HPLC, ESI-MS, and UV.Statistical Analysis:One-way ANOVA and Post hoc–Tukey test were used.Results:Presence of PCA was detected in group 1 (CHX + NaOCl), group 2 (CHX + neem) and group 3 (CHX + tusli) in all the sensitive methods employed.Conclusion:The presence of PCA in precipitate was confirmed by TLC, CC, HPLC, ESI-MS, and UV. Based on the results of the present study, we assume that components in CHX are responsible for precipitate formation which contains PCA as well. Extrusion of precipitate beyond the apex may cause periapical tissue damage and delay wound healing at the same time.

Assessment of Precipitate Formation on Interaction of Chlorhexidine with Sodium Hypochlorite, Neem, Aloevera and Garlic: An in vitro Study

Introduction: Irrigants play an important role in debridement and disinfection of root canal space. Precipitate formed from combination of irrigants during root canal treatment may affect the properties of intracanal medicaments and adaptation of obturated materials to the root canal walls. Aim: To check for precipitate formation from various irrigant combinations and to weigh the amount of precipitate formed. Methods and Material: Five different irrigants namely 2% CHX gluconate, 3% NaOCl, 5% Neem, 5% Aloevera, and 5% Garlic were taken in different test tubes. 1mL each of two different irrigants were mixed in 10 test tubes and observed for 2 min for formation of any precipitate and the formed precipitate was weighed. Results: 1mL 2% CHX +1mL 3% NaOCl and 1mL 2% CHX + 1mL 5% Neem showed precipitate formation immediately. Through statistical analysis it was observed that more amount of precipitate was seen in 1mL 2% CHX + 1mL 5% Neem followed by 1mL 2% CHX + 1mL 3% NaOCl. Conclusion: Precipitate formation is seen more with the 2% CHX?5% Neem when compared with the control group (2% CHX-3% NaOCl).

Characterization of clinically used oral antiseptics as quadruplex-binding ligands.

Approaches to characterize the nucleic acid-binding properties of drugs and druglike small molecules are crucial to understanding the behavior of these compounds in cellular systems. Here, we use a Small Molecule Microarray (SMM) profiling approach to identify the preferential interaction between chlorhexidine, a widely used oral antiseptic, and the G-quadruplex (G4) structure in the KRAS oncogene promoter. The interaction of chlorhexidine and related drugs to the KRAS G4 is evaluated using multiple biophysical methods, including thermal melt, fluorescence titration and surface plasmon resonance (SPR) assays. Chlorhexidine has a specific low micromolar binding interaction with the G4, while related drugs have weaker and/or less specific interactions. Through NMR experiments and docking studies, we propose a plausible binding mode driven by both aromatic stacking and groove binding interactions. Additionally, cancer cell lines harbouring oncogenic mutations in the KRAS gene exhibit increased sensitivity to chlorhexidine. Treatment of breast cancer cells with chlorhexidine decreases KRAS protein levels, while a KRAS gene transiently expressed by a promoter lacking a G4 is not affected. This work confirms that known ligands bind broadly to G4 structures, while other drugs and druglike compounds can have more selective interactions that may be biologically relevant.

Interaction of chlorhexidine with trisEDTA or miconazole in vitro against canine meticillin-resistant and -susceptible Staphylococcus pseudintermedius isolates from two UK regions.

Topical therapy is an important alternative to systemic antibacterial therapy for treatment of canine superficial pyoderma in light of the emergence of multidrug-resistant staphylococci. Chlorhexidine is widely used in shampoo products alone or in combination with miconazole or tromethamine-ethylenediaminetetraacetic acid (trisEDTA). Comparisons of these combinations have not been made. To determine minimum inhibitory concentrations (MICs) of combinations of chlorhexidine/miconazole and chlorhexidine/trisEDTA in vitro in a collection of Staphylococcus pseudintermedius (SP) from northern (NUK) and southeastern (SEUK) United Kingdom (UK) sources. MICs of chlorhexidine, miconazole, trisEDTA and combinations of chlorhexidine/miconazole (1:1) or chlorhexidine/trisEDTA (80:16:1 and 80:5:1) were determined for 196 canine SP isolates from NUK [49 meticillin-resistant (MRSP), 50 meticillin-susceptible (MSSP)] and fom SEUK (48 MRSP, 49 MSSP) using agar dilution. TrisEDTA alone did not inhibit growth. Chlorhexidine/miconazole MICs (median = 0.5 mg/L) were lower than those of either drug alone (P < 0.05) and lower than chlorhexidine/trisEDTA MICs (median = 1 mg/L; P < 0.0005) in each bacterial type and from both regions, except for miconazole in NUK MSSP. An additive interaction was noted between chlorhexidine and miconazole or trisEDTA (80:16:1 ratio) in 79 and 43 isolates, respectively, whereas antagonism between chlorhexidine and trisEDTA was noted for three isolates. NUK isolates were more susceptible than SEUK isolates (P < 0.05), except MRSP exposed to chlorhexidine and the chlorhexidine/trisEDTA (80:16:1) combination. These low MICs are likely to be exceeded by topical therapy. Evaluation of the mechanisms by which chlorhexidine combinations interact to reduce MICs is warranted, in view of increasing concerns of biocide tolerance in staphylococci.

Interaction of chlorhexidine with MDP-based dentin bonding systems

Interaction of chlorhexidine with MDP-based dentin bonding systems

The influence of various counter ions on the interaction of chlorhexidine with the hydrophilic contact lens polymer, poly(2-hydroxyethyl methacrylate).

The commercially available salts of chlorhexidine were found to interact with the hydrogel poly (2-hydroxyethyl methacrylate) to different extents, the affinity for the polymer decreasing in the order acetate, gluconate, chloride. The uptakes of the acetate and gluconate salts were almost entirely irreversible over the concentration range studied. The influence of some alternative counter ions, namely amino acids and dicarboxylic acid salts, was examined and found to generate a three-fold variation in the extent of the chlorhexidine interaction. Uptakes were greatest for counter ions that were either hydrophobic in character or bore a net negative charge. Only two compounds, glycine and monosodium oxalate, were successful in reducing the extent of sorption below that observed for chlorhexidine hydrochloride.

Interaction of Chlorhexidine With Smooth and Rough Types of Titanium Surfaces

Chlorhexidine (CHX) digluconate exerts plaque inhibitory efficacy in the natural dentition environment due to a superior degree of persistence at the tooth surface. The purpose of the present study was to assess the interaction of CHX with titanium surfaces to estimate its antiplaque potential in the peri-implant environment. Saliva-coated machined smooth (S) and sand-blasted acid-etched rough (R) titanium disks were soaked in either 0.1% or 0.2% CHX solution. After 24 hours, CHX amounts that were adsorbed, washed out, and desorbed from the titanium surfaces were determined spectrophotometrically at 230 nm. The antibacterial activity of CHX-treated titanium disks was assessed by measuring bacterial inhibition zones on Streptococcus mutans lawns. Titanium disks adsorbed 3% to 8% of the available CHX, which was significantly higher with 0.2% CHX (P<0.001) than with 0.1% CHX and two-fold higher on the R titanium disks compared to S titanium surface (P<0.001). After rinsing with water, 2.2% of the adsorbed CHX was washed out. Over 24 hours, S- and R-type disks released 1.1% and 0.6% of the adsorbed agent, respectively. Larger bacterial inhibition zones were obtained with 0.2% CHX and in R disks compared to S disks. CHX displayed persistence at the titanium surface. The adsorption level and bacterial growth inhibition were affected by CHX concentration and titanium surface characteristics, with higher levels of adsorption and antibacterial activity with 0.2% CHX and rough titanium surface. The slow CHX release rate suggests persistence of this agent at the titanium-pellicle surface, which can provide a long-term antiplaque effect.

New data on biological effects of chlorhexidine: Fe 2+ induced lipid peroxidation and mitochondrial permeability transition

Chlorhexidine (CHX) is a bis-bis-guanide with anphipatic and antiseptic properties and is largely used in dentistry, mainly for management of periodontal problems and in oral pre-operatory procedures. The present study concerns the effect of CHX on lipid peroxidation, mitochondrial permeability transition (MPT), and the interaction of CHX with ferritin (HoSF). CHX (100 μM) increased iron release from HoSF by ∼13-fold when compared to control values. CHX also increased iron-dependent lipid peroxidation. MPT induced by CHX was protected by ethylene glycol-bis(β-aminoethyl-ether)- N, N, N′, N′-tetraacetic acid (EGTA), dithiothreitol (DTT), and cyclosporin A (CsA), showing a Ca 2+-dependent effect, in which oxidation of thiol groups is involved, as well as the involvement of the transmembrane proteinaceous pore. BHT, catalase or o-phenanthroline did not protect MPT induced by CHX. This suggests that a ROS-independent mechanism is involved in the induction of MPT.

Charge-Transfer Chromatography Used To Study The Interaction of Chlorhexidine with Proteins and Amino Acids

Abstract The interaction of the antibacterial agent chlorhexidine (1,1-hexamethylene-bis-/5-(4-chlorophenyl)-bis-guanidine/) with human albumin and pepsin and with amino acids was studied with reversed-phase charge transfer chromatography in the presence of various monovalent cations. It was established that the mobility of chlorhexidine increases in the presence of ions in the lower concentration range (0.001 – 0.1 M) then increases at higher concentrations. The ion radii significantly influences the effect. Stepwise regression analysis proved that the chlorhexidine binds both to pepsin and human albumin, the binding is stronger with human albumin. The ions modify the character of chlorhexidine-human albumin binding indicating the hydrophilic character of the interaction. Except Asp and Glu the other amino acids exhibited weak interactions with chlorhexidine, no significant difference was found between the interactive strength of L- and D-forms of Asp and Glu. Our data make probable that hydrophilic bind...

Interaction of chlorhexidine with cytoplasmic membranes of Streptococcus mutans GS-5.

Cytoplasmic membranes of Streptococcus mutans GS-5 were extracted by incubating cells with 1% sodium lauroyl sarcosinate for 20 min at room temperature. The profiles of membrane proteins were determined by SDS-PAGE and isoelectric focusing. The effect of chlorhexidine digluconate on cell membranes was studied after treating the extracted proteins for 30 min with the drug at final concentrations of 0.05 and 0.2%. Chlorhexidine caused selective reduction in the intensity of the membrane proteins. Five densely staining bands with molecular weights of 24.2, 19.6, 18.1, 17.6 and 16.4 kD were obviously diminished. Isoelectric focusing indicated that chlorhexidine preferably precipitated acidic cytoplasmic proteins (pI 4.0-4.92). Our results are consistent with the hypothesis that the mode of action of this drug is mainly attributed to its hydrophilic property. Chlorhexidine, being cationic, may interact with bacteria by attraction to negative-charge membrane components.

Interaction of chlorhexidine with yeast cells

The effects on yeast cells of two related compounds, chlorhexidine and paludrine. were compared with those of cetyltrimethylammonium bromide (CTAB). The action of chlorhexidine closely resembles that of CTAB, following an all-or-none pattern. Involvement of membrane lipids is suggested by the similar effect of chlorhexidine and CTAB on liposomes. The possibility, that the disruptive effect of positive surfactants is due to their penetration of the region of the glycerol moieties of membrane lipids is discussed.