Cetylpyridinium Research Articles

Ewolucja płukanek – przegląd piśmiennictwa

Introduction. Mouthwashes were developed to aid oral hygiene and decontamination. They can be single-ingredient or multi-ingredient (active ingredients [antibacterial and/or antifungal], emulsifiers, detergents, acids, colourings, fragrances and flavourings, water, some alcohol). The first mouthrinse, with a documented formulation, is Listerine® and is already 150 years old. Aim. Presentation the current state of knowledge on mouthwashes with regard to their effects on the human body (human cell vitality) and restorative materials (change in color, roughness, hardness). Material and methods. Pubmed, Scopus, Wiley databases were searched, including keywords: “mouthwash”, “mouthrinse”, “composite”, “hardness”, “roughness”, “colour stability”. Results. The effects of the individual active substances (fluoride compounds, xylitol, chlorhexidine, cetylpyridinium chloride, essential oils, herbal extracts) are presented and discussed. Mouthwashes were ranked according to own classification. Indications, contraindications and the most important factors modifying the conditions of use of the mouthrinses with regard to their active ingredients were discussed. The effects of the mouthrinses on living cells and dental restorative materials were discussed. Conclusions. Mouthwashes are an important component in the fight against biofilm (chemical component), and are an integral component of proper oral hygiene. Technological advances and the deepening of the state of knowledge necessitate an update of the rules of their use. The issue of potential interactions not only of the active ingredients, but of all rinse components with both human body cells and dental restorative materials remains important.

Randomized clinical trial to assess the impact of oral intervention with cetylpyridinium chloride to reduce salivary SARS-CoV-2 viral load.

Aerosols released from the oral cavity help spread the SARS-CoV-2 virus. The use of a mouthwash formulated with an antiviral agent could reduce the viral load in saliva, helping to lower the spread of the virus. The aim of this study was to assess the efficacy of a mouthwash with 0.07% cetylpyridinium chloride (CPC) to reduce the viral load in the saliva of Coronavirus disease 2019 (COVID-19) patients. In this multi-centre, single-blind, randomized, parallel group clinical trial, 80 COVID-19 patients were enrolled and randomized to two groups, namely test (n=40) and placebo (n=40). Saliva samples were collected at baseline and 2h after rinsing. The samples were analysed by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and an enzyme-linked immunosorbent assay test specific for the nucleocapsid (N) protein of SARS-CoV-2. With RT-qPCR, no significant differences were observed between the placebo group and the test group. However, 2h after a single rinse, N protein concentration in saliva was significantly higher in the test group, indicating an increase in lysed virus. The use of 0.07% CPC mouthwash induced a significant increase in N protein detection in the saliva of COVID-19 patients. Lysis of the virus in the mouth could help reduce the transmission of SARS-CoV-2. However, more studies are required to prove this.

Synergistic reinforcement of CPC/TX-100 mixed micellar microenvironment for diperiodatocuprate(III) (DPC) oxidation of 1-propanol and 1,3-propanediol

The realization of employment of two surfactants in organic transformation comes from the intensity on achievement of better results with lower concentrations of individual surfactants than with single surfactants. In this work, the oxidations of 1-propanol and 1,3-propanediol by copper(III)-periodate (DPC) complex in aqueous micellar media were investigated, separately. The kinetic measurements were conducted by recording UV–visible absorbance spectra following the pseudo-first order condition. The isolated oxidized products were identified by assigning 1H NMR and FTIR studies. Both the oxidations were considerably promoted by the presence of micro-environment, constituted by CPC (cetylpyridinium chloride) and TX-100 (Triton-X 100) surfactants, individually. The maximum catalytic achievement was ascertained while both the surfactants were exist in equimolar amount in the reaction media. The aggregation of binary surfactants to produce a balanced mixed micelle is crucial to analyze the absolute kinetic results of present oxidation study. The electrostatic interaction between charged micelle and DPC facilitates to bring about the oxidizing species closest approach to the substrate (1-propanol and/or 1,3-propanediol) which are usually solubilized in micellar micro-environment.

Mixed micellar solubilization for procion blue MxR entrapment and optimization of necessary parameters for micellar enhanced ultrafiltration

In this study, micellar enhanced ultrafiltration, MEUF, being an active methodology, has been employed to remove Procion Blue MxR (PBM) from synthetic effluent. MEUF is being applied to reduce the toxicity level of aqueous system using the micellar media of cationic surfactants i.e. Cetyl trimethylammonium bromide (CTAB) and cetylpyridinium chloride (CPC). Subsequently, the effect of addition of nonionic surfactant, Triton X-100 (TX-100), on solubilizing power of cationic surfactants is investigated. The values of partition coefficient and free energy of partition reflect the extent of interaction of the dye with the surfactants. Initially molecules of pollutants i.e. dye form ion pairs with ionic surfactants and, later on, the same is incorporated within micelle. Maximum value of free energy of partition ΔGp has been found to be −55.49 kJmol-1 and -50.43 kJmol in the presence of CPC and CTAB, respectively. The size of pollutant, thus, increases and, consequently, can be easily filtered. The effect of various factors i.e. concentration of surfactant, concentration of electrolyte (NaCl), transmembrane pressure, revolutions per minute (RPM) and pH, have been investigated to find the optimum conditions for maximum removal of PBM from aqueous system. The efficiency of MEUF has been assessed by calculating the values of rejection percentage and permeate flux. Both the surfactants were observed as strong candidates for PBM encapsulation but overall, maximum rejection percentage (R%) of 96.90% was attained by CPC.

The antibiofilm activity of selected substances used in oral health prophylaxis

Oral health is a window to a patient’s general well-being. Balance in oral microbiome functions is crucial for health maintenance. A state of oral dysbiosis may lead to a variety of local and systemic pathological conditions. The presence of dental plaque is related to the majority of oral infections. Proper oral hygiene is crucial and the most economic practice contributing to oral health prophylaxis. Aside from prophylactic treatments provided by dental practitioners, mouth rinses, containing antimicrobial agents, are one of the possible tools used for oral care. Our study was to determine whether available mouth rinses and selected products dedicated for professional use are efficient to eradicate biofilm formed by reference and clinical strains of Streptococcus mutans, Streptococcus sanguinis, Streptococcus oralis, Streptococcus mitis, Staphylococcus aureus, Enterococcus faecalis, Lactobacillus rhamnosus and Candida albicans on the surface of hydroxyapatite – major mineral component of a tooth. Therefore, such antimicrobials as chlorhexidine, cetylpyridine chloride, polyhexanide, silver nanoparticles, sulphonated phenolics, and natural antiplaque essential oils and coconut oil were analyzed. Applied experimental settings in in vitro models were designed to reflect accurately the recommended use of the tested substances, therefore four types of eradication procedure were conducted. Sialorrhea simulation was also performed to evaluate antibiofilm potential of diluted mouth rinses. Biofilm was investigated with quantitative method where absorbance values were measured. Statistical differences were assessed using the Kruskal–Wallis test with a post-hoc Dunnett’s analysis. Results have shown that biofilms displayed a diversified sensitivity to the tested antimicrobials. The highest antibiofilm activity was detected for cetylpyridine chloride while the lowest for chlorhexidine. However the differences in E. faecalis biofilm reduction observed after the use of these two compounds were not statistically significant (p > 0.05), whereas all observed differences in S. aureus survival after exposure to the examined antimicrobial agents were statistically significant (p < 0.5). The PHMB, both in standard and in sialorrhea simulated conditions had the highest potential against streptococci. The coconut oil reduced C. albicans fungus biofilm by 65.48% but low eradication level was observed in case of bacterial biofilms. The dehydrating mechanism of action of sulfonated phenolics turned out to be ineffective against streptococcal biofilm which in turn was effectively eradicated by silver nanoparticles. The implementation of Antibiofilm Dressing's Activity Measurement method allowed to observe strain-related differences in terms of antimicrobial sensitivity. The obtained results may be introduced in everyday out-patient dental plaque prophylaxis as well as clinical environment.

SPECTROPHOTOMETRIC DETERMINATION OF STIBIUM (III) WITH 6,7-DIHYDROXY‑4-CARBOXYL‑2- PHENYLBENZOPYRILIUM PERCHLORATE

In the current study, the peculiarities of the complexation of Stibium(III) with 6,7-dihydroxy‑4-carboxyl‑2-phenylbenzopyrylium perchlorate (CDC) in binary systems and in the presence of cationic surfactants (Surf) were studied. Using classical spectrophotometric methods of molar ratios and equilibrium shift, it was found that in two systems two complexes with stoichiometry Sb(III): CDC are formed: 1:2 and 1:3 at pH 2.5 and pH 6.0, respectively. Molar absorptivity coefficients were calculated for Sb(III) complexes with CDC, which are 1.2⋅104 and 1.1⋅104, respectively. It is shown that in the presence of cetylpyridinium chloride or cetyltrimetrylammonium bromide complexes with a molar ratio of Sb(III): CDC: Surf =1:3:3 are formed. In the presence of cationic surfactants there is no shift in the optimal pH of complexation, but there is an increase in the number of coordinated reagent molecules due to the loosening of the hydrate shell of the ion Sb(III) due to hydrophobic hydration of the complex. In addition, the introduction of cationic surfactants leads to a batochromic shift of the absorption band by 10–15 nm and an increase in the molar absorptivity to 2.8⋅104 and 3.4⋅104 when cetylpyridinium chloride or cetyltrimetrylammonium bromide were used respectively. The method of spectrophotometric determination of Stibium(III) was developed using an analytical form based on the ternary complex Sb(III): KDC: Surf = 1:3:3, which was tested during the analysis of samples of polymer materials (polyethylene terephthalate). It is noted that the developed technique is characterized by satisfactory reproducibility and is not inferior in sensitivity to known analogues.

TO THE PROBLEM ON THE OXIDATION MECHANISM OF AZO DYES ON MODIFIED CARBON-PASTE ELECTRODES

In the current study, using a carbon-paste electrode modified with β-cyclodextrin oligosaccharide, the oxidation mechanism of some useful food azo dyes as Sunset Yellow FCF, Tartrazine, Allura Red AC, Carmoisine, Ponceau 4R was established. Cyclic voltammetry was used to investigation redox behaviour of studied food azo dyes (Sunset Yellow FCF, Tartrazine, Allura Red AC, Carmoisine, Ponceau 4R). It was established that such dyes as Sunset Yellow FCF and Ponceau 4R are oxidized quasi-reversibly, and such as Tartrazine, Carmoisine and Allura Red AC are completely irreversibly oxidized. It was noted that for all dyes, except Tartrazine, after oxidation on a cyclic voltammogram, a new reversibly redox pair is formed. This may indicate the formation of new electroactive fragments during the oxidation of azo dyes (Sunset Yellow FCF, Allura Red AC, Carmoisine, Ponceau 4R). Based on the conducted studies of the effect of pH and scanning rate on the oxidation potential of studied azo dyes, it was established that 2 electrons and 1 proton participate in the oxidation process for all dyes, except for Carmoisine, for which oxidation takes place with the participation of 1 proton and 1 electron. Based on the obtained information, as well as using information from our previous studies on the redox behavior of azo dyes (Sunset Yellow FCF, Tartrazine, Allura Red AC, Carmoisine, Ponceau 4R) on carbon-paste electrode modified by silica impregnated with cetylpyridinium chloride cationic surfactant, a scheme for the oxidation of azo dyes was proposed. According to the scheme, oxidation takes place with the participation of an irreversible chemical reaction, which leads to the further rearrangement of bonds with the breaking of the azo group of dyes and the formation of new electroactive fragments.

FSVPy: A python-based package for fluorescent streak velocimetry (FSV)

Predictive constitutive equations that connect easy-to-measure transport properties (e.g., viscosity and conductivity) with system performance variables (e.g., power consumption and efficiency) are needed to design advanced thermal and electrical systems. In this work, we explore the use of fluorescent particle-streak analysis to directly measure the local velocity field of a pressure-driven flow, introducing a new Python package (FSVPy) to perform the analysis. Fluorescent streak velocimetry combines high-speed imaging with highly fluorescent particles to produce images that contain fluorescent streaks, whose length and intensity can be related to the local flow velocity. By capturing images throughout the sample volume, the three-dimensional velocity field can be quantified and reconstructed. We demonstrate this technique by characterizing the channel flow profiles of several non-Newtonian fluids: micellar Cetylpyridinium Chloride solution, Carbopol 940, and Polyethylene Glycol. We then explore more complex flows, where significant acceleration is created due to microscale features encountered within the flow. We demonstrate the ability of FSVPy to process streaks of various shapes and use the variable intensity along the streak to extract position-specific velocity measurements from individual images. Thus, we demonstrate that FSVPy is a flexible tool that can be used to extract local velocimetry measurements from a wide variety of fluids and flow conditions.

Phosphatidylinositol 4,5-Bisphosphate Mediates the Co-Distribution of Influenza A Hemagglutinin and Matrix Protein M1 at the Plasma Membrane.

The fully assembled influenza A virus (IAV) has on its surface the highest density of a single membrane protein found in nature-the glycoprotein hemagglutinin (HA) that mediates viral binding, entry, and assembly. HA clusters at the plasma membrane of infected cells, and the HA density (number of molecules per unit area) of these clusters correlates with the infectivity of the virus. Dense HA clusters are considered to mark the assembly site and ultimately lead to the budding of infectious IAV. The mechanism of spontaneous HA clustering, which occurs with or without other viral components, has not been elucidated. Using super-resolution fluorescence photoactivation localization microscopy (FPALM), we have previously shown that these HA clusters are interdependent on phosphatidylinositol 4,5-biphosphate (PIP2). Here, we show that the IAV matrix protein M1 co-clusters with PIP2, visualized using the pleckstrin homology domain. We find that cetylpyridinium chloride (CPC), which is a positively charged quaternary ammonium compound known for its antibacterial and antiviral properties at millimolar concentrations, disrupts M1 clustering and M1-PIP2 co-clustering at micromolar concentrations well below the critical micelle concentration (CMC). CPC also disrupts the co-clustering of M1 with HA at the plasma membrane, suggesting the role of host cell PIP2 clusters as scaffolds for gathering and concentrating M1 and HA to achieve their unusually high cluster densities in the IAV envelope.

Thermodynamics of Aggregation between the Cationic Surfactant and Polymer Based on Biodegradable Poly(vinyl Alcohol).

The formation of aggregates between carboxylated (PVCOOH) or neutral hydrolyzed (PVOH) poly(vinyl alcohol) and hexadecylpyridinium chloride (C16PyCl) was examined by conductimetry, turbidimetry, and isothermal titration calorimetry (ITC) in the presence of different NaCl concentrations. The interaction between the polymers and C16PyCl in pure water showed a critical aggregation concentration (cac = 0.8 mmol L-1) only for the neutral polymer. PVCOOH interacted with the surfactant through electrostatic attraction, forming macroscopic aggregates. Integral enthalpy changes for aggregate formation (ΔHagg) obtained from ITC curves varied from -0.61 (for the PVOH system in pure water) to -4.14 kJ mol-1 (for PVOH in the presence of 10.0 mmol L-1 NaCl), indicating that the formation of the aggregates was enthalpically favored. However, hydrophobic interactions drove the process for low surfactant concentration for both polymers. Saturation concentrations (C2) obtained from conductimetry were smaller than those from ITC, revealing that the binding of C16PyCl on the chain of the polymers at higher surfactant concentrations shows the same electric properties as that of free micelles on the solution. Increase of the ionic strength favored the aggregation and decreased the complexity of the ITC curves, suggesting that the reorganization of the surfactant monomers on the polymeric chain with the increase in their concentration was suppressed.

A randomized controlled trial to evaluate the effectiveness of a novel mouth rinse in patients with gingivitis

BackgroundThis single-center, randomized controlled trial aimed to determine the effectiveness of a novel, biofilm-disrupting, mouth rinse that combines Cetylpyridinium chloride (CPC) and essential oils in preventing re-accumulation of supragingival plaque and supragingival microbiome in patients with gingivitis after dental prophylaxis.MethodsOne hundred eighteen participants were randomly assigned in a 1:1 ratio to receive twice-daily test mouth rinse (59) or carrier rinse control (59) for 12 weeks after dental prophylaxis.ResultsIn a per-protocol analysis that included patients who completed the intervention, the treatment group (39) had significantly lower supragingival plaque scores at 6 and 12 weeks compared to the control group (41; p = 0.022). Both groups showed similar improvement in gingivitis score, but neither group had improvement in bleeding score or probing depth. Thirty-eight (29%) patients did not complete the study due to loss of follow-up (17) or early discontinuation of the assigned intervention (21). Microbiome sequencing showed that the treatment rinse significantly depleted abundant and prevalent members of the supragingival plaque microbiome consortium.ConclusionsAmong patients with gingivitis, the novel mouth rinse significantly reduced re-accumulation of supragingival plaque following dental prophylaxis by depleting supragingival plaque microbiome. However, long-term adherence to the rinse may be limited by adverse effects (ClinicalTrials.gov number, NCT03154021).

Alginic Acid Beads Containing Fluorescent Solvatochromic Dyes Display an Emission Color Response to a Cationic Surfactant.

Lipophilic fluorescent dyes can be employed as sensors for surfactants present in concentrations above the critical micellar concentration (CMC) where the dyes are monodispersed in micelles. However, the surfactant concentration range over which these dyes are effective is narrowed because by the sigmoidal nature of their responses. To overcome this limitation, we developed a novel sensor material comprised of a labeled fluorescent solvatochromic dye covalently bonded to alginate gel, which is known to strongly adsorb cationic surfactants. We hypothesized that the dye-alginate conjugate would undergo fluorescent color changes in response to binding of surfactants which alter the polarity of the surrounding environment. Indeed, addition of the representative cationic surfactant, cetylpyridinium chloride (CPC), to an aqueous solution of the alginate conjugated fluorescent solvatochromic dye leads to a visible fluorescent color change when the concentration of CPC is below the CMC. The average values of the color appearance parameter, referred to as a hue, of light emitted from gels, calculated by analysis of fluorescence microscopy images using ImageJ software, were found to be approximately linearly dependent on the concentration of CPC encapsulated in the alginate-fluorescent dye complex. This finding shows that absorbed CPC can be quantitatively determined over a wide concentration range in the form of simple fluorescence wavelength or visible responses.

Isolation of nontuberculous mycobacteria species from different water sources: a study of six hospitals in Tehran, Iran

PurposeNontuberculous mycobacteria (NTM) are ubiquitous bacteria that are naturally resistant to disinfectants and antibiotics and can colonize systems for supplying drinking water. Therefore, this study aimed to evaluate the prevalence of NTM in the drinking water of six hospitals in Tehran, Iran.MethodsTotally, 198 water samples were collected. Each water sample was filtered via a membrane filter with a pore size of 0.45 µm and then decontaminated by 0.005% cetylpyridinium chloride. The membrane filters were incubated on two Lowenstein-Jensen media at 25 °C and 37 °C for 8 weeks. The positive cultures were identified with phenotypic tests, and then NTM species were detected according to the hsp65, rpoB, and 16S rDNA genes. Drug susceptibility testing (DST) was also carried out.ResultsOverall, 76 (40.4%) of the isolates were slowly growing mycobacteria (SGM) and 112 (59.6%) of the ones were rapidly growing mycobacteria (RGM). The most common NTM were Mycobacterium aurum, M. gordonae, M. phocaicum, M. mucogenicum, M. kansasii, M. simiae, M. gadium, M. lentiflavum, M. fortuitum, and M. porcinum. Among these 188 samples, NTM ranged from 1 to > 300 colony-forming unit (CFU) /500 mL, with a median of 182 CFU/500 mL. In the infectious department of all hospitals, the amount of CFU was higher than in other parts of the hospitals. The DST findings in this study indicated the diversity of resistance to different drugs. Among RGM, M. mucogenicum was the most susceptible isolate; however, M. fortuitum showed a different resistance pattern. Also, among SGM isolates, M. kansasii and M. simiae, the diversity of DST indicated.ConclusionsThe current study showed NTM strains could be an important component of hospital water supplies and a possible source of nosocomial infections according to the CFU reported in this study. The obtained findings also help clarify the dynamics of NTM variety and distribution in the water systems of hospitals in the research area.

On the structure of cetylpyridinium perchlorate: A combined XRD, NMR, IR and DFT study

Cetylpyridinium perchlorate has been synthesized and characterized by using the differential thermal analysis (DTA), X-ray powder diffraction (XRD) techniques, Fourier transform infrared spectroscopy (FT-IR), and 1H and 13C nuclear magnetic resonance (NMR) spectroscopy. The investigated salt melts congruently at 100 °C. The DTA and XRD results indicate that the cetylpyridinium perchlorate samples synthesized at different temperatures differ in crystallinity. It has been established that the crystallinity degree of the samples affects the decomposition temperature. The highest decomposition temperature (Td = 265 °C) is observed for the sample crystallized at 20 °C. Cetylpyridinium perchlorate crystallizes in the monoclinic crystal system with the cell parameters a = 20.31 Å, b = 16.20 Å, c = 7.25 Å, β = 95.26°, Z = 4.According to the DFT calculations, the interionic interactions in the structure are characterized by electron transfer from the perchlorate anion to the cetylpyridinium cation. This explains a noticeable difference in the 1H NMR chemical shifts of the hydrogen atoms in the ortho-position (∼0.2 ppm) and the α-methylene group (∼0.1 ppm) of the DMSO solutions of the cetylpyridinium perchlorate and chloride salts micelles. The electronic structure analysis of cetylpyridinium perchlorate and cetylpyridinium chloride in terms of the “quantum theory of atoms-in-molecules” and the analysis of non-covalent interactions with the “reduced density gradient” method have revealed the presence of strong interactions between the ions in the DMSO solution.

Interaction of metanil yellow dye with cationic surfactants: Conductometric and spectroscopic studies

Conductometric and spectroscopic methods were used to examine the interactions among the cationic surfactants, tetradecyltrimethylammonium bromide (TTAB) and cetylpyridinium chloride (CPC), and the anionic azo dye metanil yellow (MY) in an aqueous solution. The standard Gibb’s energy (ΔGm0), enthalpy (ΔHm0), and entropy (ΔSm0) of micellization were determined with the help of the equilibrium model. With temperature rise, the critical micelle concentration (cmc) increases because of the interruption of the organized water (WR) molecules enclosing the surfactant’s hydrophobic groups. As the total carbon atoms of the hydrophobic group are more in CPC than TTAB, a considerable fall in cmc value was observed. The presence of MY caused a higher degree of ionization (α) of micelles of TTAB and CPC. The negative values of ΔGm0 and ΔHm0 for both the surfactants in WR and aqueous MY solution (WR-MY) show that the micellization process is spontaneous and exothermic. As indicated by the -TΔSm0 values, which were found to be greater than ΔHm0 values, the entropy gain is typically what regulates the micellization process and the micellization was found to have a negative heat capacity (ΔCp,m0). UV–Visible spectra show that CPC has a higher binding constant (Kb) value as compared to TTAB implying that CPC has a comparatively greater binding affinity with MY dye in aqueous media (WR). The decreasing value of ΔGb for CPC indicates that the chance for the MY–CPC complex formation is more than that of the MY–TTAB complex. As shown by the rise in absorbance values as surfactant concentrations increase, a large number of the MY molecules are attracted to TTAB and CPC micelles.

Spectrophotometric Determination of Lanthanum (III) With Bromopyrogallol Red And Cetylpridinium Chloride -Applications in Natural Waters and Urine

A highly sensitive spectrophotometric procedure for the estimation of lanthanum in aqueous medium has been established. The method was involved the reaction of lanthanum with bromopyrogallol as chelating agent in the presence of cetylpyridinium chloride at pH4.61 to produce a soluble blue colour ternary complex exhibited maximum absorption at 661nm. The method adheres to Beer's low over the concentration range 0.125 –5.0 μg/ml with coefficient determination (r2= 0.9987). The molar absorptivity(ℇ) of the ternary complex (La(III)-BPR-CPC) is 5.39x104 M-1cm-1 which corresponds to Sandell's sensitivity index of 0.00258 μg.cm-2. The stoichiometric composition of the ternary complex was estimated and found to be (1:2:4) (La:BPR:CPC), respectively. The values of detection limit (DL) and quantitation limit (QL) were calculated and found to be 0.0630 and 0.0817 μg.ml-1, respectively. A recovery% was found in the range 95.3% to 103.5%, while the precision (RSD) was estimated in the range 0.126 to 1.705. The proposed procedure has been applied successfully for the determination of lanthanum in natural waters and urine sample.

Mouthwashes and the Effect on the Viral Load of SARS-CoV-2 in Saliva: A Literature Review

BACKGROUND: At present, several active ingredients have been investigated in mouthwashes having certain virucidal properties, which could reduce the viral load of SARS-CoV-2 to avoid contamination in medical or dental practice. AIM: The objective of this review is to analyze the available evidence regarding mouthwashes and their effect on the salivary viral load of SARS-CoV-2. METHODS: Records were retrieved from databases such as PubMed, Scopus, Web of Science, and Virtual Health Library up to June 21, 2022. Randomized or non-randomized clinical trials were included where saliva samples and laboratory or in vitro studies were used in the presence of saliva. RESULTS: After a systematic selection process, 11 clinical studies that evaluated at least one mouthwash within clinical protocols and three laboratory studies that evaluated the virucidal efficacy against SARS-CoV-2 in the presence of saliva were finally included. CONCLUSION: There are oral disinfectants with virucidal action in saliva samples, under clinical and laboratory conditions, capable of reducing the viral load of SARS-CoV-2. Cetylpyridinium chloride, chlorhexidine, and povidone-iodine present the best results so far. However, it was also possible to find active principles of recent appearance that, based on favorable exploratory results, needs further investigation on their efficacy and possible adverse events.

Surface-Enhanced Raman Scattering Imaging of Cetylpyridinium Chloride Adsorption to a Solid Surface.

Surface active agents (surfactants) have found a variety of critical technological applications, from helping infant lungs breathe to fugitive dust control at industrial sites. Surfactant molecules adsorb to an interface and facilitate a decrease in the surface free energy (interfacial tension) between two immiscible phases. However, a limited number of methods (e.g., holography and fluorescence microscopy) achieved visualization of surfactant molecule distribution in multiphase systems qualitatively. To probe the efficacy and/or adsorption density of surfactants at such interfaces quantitatively, we demonstrate here a direct observation of surfactant adsorption by surface-enhanced Raman scattering (SERS). This work details the development of a research platform to study surfactant adsorption using Raman imaging. The imaging and analysis were successfully benchmarked against conventional interfacial tension measurements and thermodynamic theory employed to estimate surfactant adsorption at equilibrium. This in situ Raman-based experimental method provides a platform to interrogate structure-function relationships that inform the design process for new surfactant species.

Validated correlation of mass loss and drug release in vitro and in healthy subjects for sugared and sugar-free cetylpyridinium chloride (CPC) and benzocaine (1.4 mg/10 mg) lozenges supports in vitro mass loss and corresponding drug release as a surrogate for local bioequivalence

A clinical study was performed to determine the in vivo mass loss of both lozenges in 16 healthy volunteers. In vitro, mass loss over time was measured for both formulations and correlated to the release of CPC and benzocaine. In vivo, the oral mass loss profiles of both lozenges were similar, with a mean difference between the two curves, up to the first point greater than 85% of 3.2%, and a f2 similarity factor of 69%. In vitro, the mass loss of both lozenges was similar and a strong correlation between mass loss and release of CPC and benzocaine was observed, indicating that the active ingredients were homogeneously dispersed within the lozenges. Based on the results, it was possible to establish a link between the in vitro and in vivo drug release and mass losses using an in vitro–in vivo correlation (IVIVC). In vivo release profiles of benzocaine and CPC were calculated and found to be similar for the sugar-free and sugared lozenges; more than 85% of the active ingredients were released in 186 and 209 s, respectively. These results suggest that in vitro mass loss and corresponding drug release is an adequate surrogate for bioequivalence studies, waiving their need for lozenges with excipient changes, and that the clinical risk–benefit profile of sugar-free CPC/benzocaine (1.4 mg/10 mg) lozenges is unlikely to differ from sugared lozenges.

Mixed Micellar Solubilization of Naphthol Green B Followed by Its Removal from Synthetic Effluent by Micellar-Enhanced Ultrafiltration under Optimized Conditions.

In this manuscript, the application of cetyltrimethylammonium bromide (CTAB) and cetylpyridinium chloride (CPC) for the removal of Naphthol Green B (NGB) as a synthetic effluent has been studied. The solubilization of NGB by a single and mixed micellar system using Triton X-100 (TX-100) as a nonionic surfactant has been performed to establish both the extent of the partitioning (kx) of NGB and ultimately their respective Gibbs free energies ΔGp as well. An applied methodology, micellar-enhanced ultrafiltration (MEUF), has also been studied in different micellar media of cationic surfactants by variation in some selective parameters, such as the concentration of surfactant, electrolyte, pressure, pH, and RPM to obtain optimum conditions. The results have been analyzed by a UV/visible double beam spectrophotometer. ΔGp was found to be −39.65 kJ/mol and −47.94 kJ/mol by CTAB and CPC, respectively, in the presence of a nonionic surfactant. The maximum value of Gibbs free energy (ΔGp) of the partition was obtained by CPC. The values of the rejection coefficient (R%) and permeate flux (J) are also calculated. A maximum removal of 99.77% and 98.53% by CTAB and CPC, respectively, was obtained. It has been observed that both of the surfactants are strong candidates for NGB removal.