Cetylpyridinium Research Articles

Sulfated polysaccharides from the viscera of Mustelus shark: Characterization and antioxidant, anticoagulant and anti-proliferative activities

In the present study, sulfated polysaccharides (SPs) from smooth hound shark were extracted using different precipitation agents, the cetylpyridinium chloride or ethanol, named SHSP-I and SHSP-II, respectively. The UV–visible scan demonstrated the absence of nucleic acids or proteins in the extracted SHSPs. The antioxidant, anticoagulant and anti-proliferative activities were also investigated. Results showed that SHSPs displayed reducing and scavenging capacities, as shown by the oxygen radical absorbance capacity, the total antioxidant capacity and the hydroxyl radical-scavenging activities. Moreover, extracted SPs were able to prolong the activated partial thromboplastin time (aPTT), the prothrombin time (PT) and the thrombin time (TT) and they reduced the fibrinogen level (FL), without inducing erythrocytes hemolysis, which indicated that they inhibited the intrinsic and extrinsic coagulation pathways and thrombin-mediated fibrin formation. The SHSP-I was more effective on prolonging the blood clotting time by more than 120 s at 1 mg/ml in the aPTT and about 70 s and 60 s at 2.5 mg/ml in the PT and TT, respectively, compared to the SHSP-II. The anti-proliferative activity of SHSPs was tested against the growth of K562 human myelogenous leukemia cells and Caco-2 colon cancer cells. Data showed that both polysaccharides have a dose-dependent inhibitory effect, where SHSP-I exhibited the strongest activity against the tested cells and the K562 was more sensitive than Caco-2 line cells to the action of SHSPs. The overall data suggested that SPs from shark viscera could be useful to be used as nutraceutical agents.

Physical, antimicrobial, and release profiles of orthodontic adhesives modified with chlorhexidine and cetylpyridinium chloride

The aim of the present study was to evaluate the properties (physical, antimicrobial, and release profiles) by using modified orthodontic adhesives on extracted teeth. Three primers, Transbond (Tx), Transbond-Chlorhexidine (Tx-CHx), and Transbond-Cetylpyridinium chloride (Tx-CTP), containing antibacterial agents CHx and CTP, were tested against Streptococcus mutans (Sm) in planktonic and biofilm phases. Their antimicrobial activities (biofilm and growth assays), affected by water aging, were analyzed along with shear bond strength and mode of fracture after bonding brackets onto bovine incisors. Tx-CHx demonstrated superior antimicrobial activity against in both planktonic and biofilm states, completely inhibiting their growth and biofilm formation. This effectiveness persisted after thermocycling. Conversely, Tx-CTP showed a positive outcome against microbial activity compared to Tx. Shear bond strength (SBS) (Tx–11.21±1.72; Tx-CTP–12.48±2.50; Tx-CHx–11.57±2.28) and bond failure interface showed no significant differences among the three primers. Adding CHx and CTP to an orthodontic primer could potentially safeguard enamel from demineralization without negatively impacting its structural characteristics.

A literature review on various agents which can be used as a mouthwash for effective oral care

There are various types of mouthwashes available in the market, which contains different types of ingredients in it, which are active and inactive in nature. A mouthwash can perform various functions like, it can provide an antimicrobial activity, can be used as a topical anti-inflammatory agent, as a topical analgesic and most commonly and importantly for the prevention of the occurrence of the caries in the oral cavity. Mouthwashes are the most common types of agents, which came in direct contact with the oral mucous membrane and can be absorbed directly into the blood stream. Different agents which can be used in the preparation of the oral mouthwashes are chlorhexidine, benzydamine hydrochloride, cetylpyridinium chloride and sodium benzoate, triclosan, oxygenating agents, sodium bicarbonate, alcohol, while on the other side the main content of the poly herbal mouth washes are clove, peppermint, green tea, ajwain, neem, tulsi and leaf of guava fruit. Usually, most therapeutic oral rinses or natural mouth rinses usually does not contain any alcohol or sugar or any type of artificial sweetener in it.

In vitro anti-Helicobacter pylori activity and antivirulence activity of cetylpyridinium chloride.

The primary treatment method for eradicating Helicobacter pylori (H. pylori) infection involves the use of antibiotic-based therapies. Due to the growing antibiotic resistance of H. pylori, there has been a surge of interest in exploring alternative therapies. Cetylpyridinium chloride (CPC) is a water-soluble and nonvolatile quaternary ammonium compound with exceptional broad-spectrum antibacterial properties. To date, there is no documented or described specific antibacterial action of CPC against H. pylori. Therefore, this study aimed to explore the in vitro activity of CPC against H. pylori and its potential antibacterial mechanism. CPC exhibited significant in vitro activity against H. pylori, with MICs ranging from 0.16 to 0.62 μg/mL and MBCs ranging from 0.31 to 1.24 μg/mL. CPC could result in morphological and physiological modifications in H. pylori, leading to the suppression of virulence and adherence genes expression, including flaA, flaB, babB, alpA, alpB, ureE, and ureF, and inhibition of urease activity. CPC has demonstrated in vitro activity against H. pylori by inhibiting its growth, inducing damage to the bacterial structure, reducing virulence and adherence factors expression, and inhibiting urease activity.

Effect of Addition of Cetylpyridinium Chloride Cationic Surfactant on the Antimicrobial Activity of Chlorhexidine Endodontic Irrigant

Background. Endodontic irrigants are essential for disinfecting the root canal system. None of the currently available irrigants perfume sufficiently. However, most products contain surfactants, which enhance the antimicrobial properties of the irrigants. Objectives. To evaluate the effect of cetylpyridinium chloride (CPC) surfactant on the antimicrobial activity of chlorhexidine and compare it with that of chlorhexidine (CHX) and Biopure MTAD against Enterococcus faecalis, Staphylococcus aureus, and Candida albicans. Materials and Methods. In this in vitro study, three microorganisms were used (E. faecalis, S. aureus, and C. albicans), and each organism was treated with three different irrigants: 2% CHX, 2% CHX + 0.2% CPC, and 100% Biopure MTAD. The antimicrobial activity was evaluated by direct contact assay for 5 min of contact time. The colony-forming unit per mL was calculated after antimicrobial treatment and 24 hr of incubation at 37°C. The data were statistically analyzed using Statistical Package for Social Science (SPSS) version 22. The Kruskal–Wallis and the multiple Wilcoxon sum rank tests were used. The level of significance was set at 0.05. Results. The result showed a nonsignificant difference between the different irrigants against E. faecalis. Among S. aureus subgroups, 2% CHX was statistically significant and more efficient than MTAD. Among C. albicans subgroups, 2% CHX and combined irrigant (2% CHX + 0.2% CPC) were statistically more efficient than MTAD. The 2% CHX and combined irrigants were equally effective against all the tested microorganisms. Conclusions. All the used irrigants have comparable effects against E. faecalis after 5 min. CHX have a comparable effects to that of the combined irrigant and more efficient against S. aureus than MTAD. CHX and the combined irrigant have potent antimicrobial activity against C. albicans superior to MTAD. CPC surfactant can be used with CHX to overcome its clinical drawbacks or limitations without altering or reducing its antimicrobial activity.

Comparison of dodecyl trimethyl ammonium bromide (DTAB) and cetylpyridinium chloride (CPC) as corrosion inhibitors for mild steel in sulphuric acid solution

Two essential cationic surfactants, dodecyl trimethyl ammonium bromide (DTAB) and cetyl pyridinium chloride (CPC) with differences in the alkyl chain, were investigated as corrosion inhibitors on mild steel (MS) in 0.5 M H2SO4 with weight loss (WL) and the potentiodynamic polarization (PDP) method. Three different temperatures were used to maintain the reported sample solutions (298.15, 308.15, and 318.15 K) for concentrations ranging below, above, and at the optimum critical micelle concentration (CMC) of the cationic surfactants. Results show that 0.5 M DTAB having ammonium group gave higher inhibition efficiency than 0.5 M CPC having pyridinium group by PDP method. The inhibition efficiencies were determined as 98.6% for 0.5 M DTAB and 89.38% for 0.5 M CPC after 24 h immersion at 298.15 K. The extreme inhibition efficiency depends on the chain length and decreases with an increase in temperature as well as increases with the addition of concentration of cationic surfactants. Around CMC, both surfactants CPC and DTAB showed the highest inhibition efficiency which follows the isotherm of Langmuir adsorption and illustrates a mixed type of corrosion inhibitors with the predominance of cathodic reactions. Additionally, the proposed mechanisms of inhibitors showing both physical and chemical adsorption confirmed by the free energy of adsorption (-ΔGads0) for DTAB were >28–34.5 kJ/mol and for CPC were >31.07–42.91 kJ/mol.

From disinfection to pathogenicity: Occurrence, resistome risks and assembly mechanism of biocide and metal resistance genes in hospital wastewaters

Hospital wastewaters (HWWs) represent critical reservoir for the accumulation and propagation of resistance genes. However, studies on biocide and metal resistance genes (BMRGs) and their associated resistome risks and driving mechanisms in HWWs are still in their infancy. Here, metagenomic assembly was firstly used to investigate host pathogenicity and transferability profiles of BMGRs in a typical HWWs system. As a result, genes conferring resistance to Ethidium Bromide, Benzylkonium Chloride, and Cetylpyridinium Chloride dominated biocide resistance genes (BRGs), whereas Cu resistance gene was the largest metal resistance genes (MRGs) contributor. Most BMRGs experienced significant reduction during anoxic-aerobic treatment and sedimentation stages but exhibited enrichment after chlorine disinfection. Network analysis indicated intense interactions between BMRGs and virulence factors (VFs). Polar_flagella, belonging to the adherence was identified to play important role in the network. Contig-based analysis further revealed noteworthy shifts in host associations along the treatment processes, with Pseudomonadota emerging as the primary carrier, hosting 91.1% and 85.3% of the BRGs and MRGs. A total of 199 opportunistic pathogens were identified to carry 285 BMRG subtypes, which mainly included Pseudomonas alcaligenes, Pseudomonas lundensis, and Escherichia coli. Notably, ruvB conferring resistance to Cr, Cetylpyridinium Chloride, and Dodine were characterized with the highest frequency carried by pathogens. Diverse co-occurrence patterns between BMRGs and mobile genetic elements (MGEs) were found from the raw influent to final effluent. Overall, 10.5% BRGs and 8.84% MRGs were mobile and among the 4 MGEs, transposase exhibited the greatest potential for the BMRGs dissemination. Furthermore, deterministic processes played a dominant role in bacterial communities and BMRGs assembly in HWWs. Bacterial communities contributed more than MGEs in shaping the resistome. Taken together, this work demonstrated widespread BMRGs pollution throughout the HWWs treatment system, emphasizing the potential for informing resistome risk and ecological mechanism in medical practice.

Drug-induced transitions from micelles to vesicles in ionic surfactant solutions

Surfactant solutions play key roles in scientific research and technological applications. Here we investigated solutions that combined an ionic surfactant, Cetylpyridinium Chloride (CPyCl), with a non-steroidal, anti-inflammatory drug, Sodium Diclofenac (Diclo). The study covered a wide range of compositions and utilized both rheology and cryogenic-Electron Microscopy (cryo-EM). The solutions were prepared at three different concentrations of CPyCl: 5.0 mM, 16.7 mM and 33.0 mM, and we maintained the ratio of surfactant to salt, R=CPyCl/Diclo, within the range of 0.24<R<1.2. Linear viscoelasticity was measured at 25°C. The use of dilute solutions allowed for detailed cryo-EM imaging. By tracking the evolution of the zero-frequency viscosity as a function of Diclo concentration, we identified distinct regions of different rheological responses. The correlation between frequency sweep data and cryo-EM images enabled us to link these regions to specific morphological transitions ranging from spherical micelles to long and entangled wormlike micelles, to branched networks and, eventually, to perforated vesicles. For some systems, we were able to measure the complete spectrum of relaxation times, including the shortest characteristic Rouse time at high frequencies, previously only achieved by Diffusive Wave Spectroscopy. The use of existing models to evaluate the relevant important microstructural parameters such as entanglement, contour, and persistence lengths allowed us to establish a clear correlation between the microstructural parameters derived through rheology and the insights from the cryo-EM analysis.

Oral Rinses: Some Kill and Some Cripple Candida albicans.

Oral healthcare professionals play a crucial role in guiding patients toward evidence-based choices among the many available oral rinses. In this study, we explored how specific oral rinse formulations affect the viability and modulate critical virulence traits of the opportunistic fungal pathogen Candida albicans. We assessed the effects of these oral rinses on the production of germ tube, production of phospholipase and hemolysin, as well as biofilm formation. We found that oral rinses containing cetylpyridinium chloride (CPC) and chlorhexidine (CHX) showed the greatest fungicidal activity with the lowest MFCs (0.38% and 0.78%, respectively). Oral rinses based on zinc chloride and sodium fluoride with Miswak bark extract (MIS) or essential oils (EO) had much lower fungicidal activity (8-16 times lower) compared to CHX and CPC. However, they had a significantly greater impact on the virulence traits of C. albicans. They reduced germ tube production by 86% - 89% (versus 42% for CHX and 29% for CPC), completely inhibited phospholipase and hemolysin production, and together with the CPC-based oral rinse, exerted the greatest reductions in biofilm formation across all tested concentrations. This was in contrast to both the controls and CHX, which had a minimal effect on biofilm formation. By inhibiting the virulence factors the oral rinse can have a crippling effect on C. albicans, weakening this opportunistic pathogen and hindering its potential to cause infection.

The Gordon–Schowalter/Johnson–Segalman model in parallel and orthogonal superposition rheometry and its application in the study of worm-like micellular systems

Parallel and Orthogonal Superposition experiments may be employed to probe a material’s non-linear rheological properties through the rate-dependent parallel and orthogonal superposition moduli, G∥∗(ω,γ̇) and G⊥∗(ω,γ̇), respectively. In a recent series of publications, we have considered the problem of interconversion between parallel and orthogonal superposition moduli as a means of probing flow induced anisotropy. However, as noted by Yamomoto (1971) superposition flows may be used to assess the ability of a particular constitutive model to describe the flow of complex fluids. Herein, we derive expressions for the superposition moduli of the Gordon–Schowalter (or Johnson–Segalman) fluid. This model contains, as special cases, the corotational Maxwell model, the upper (and lower) convected Maxwell models, the corotational Jeffreys model, and the Oldroyd-B model. We also consider the conditions under which the superposition moduli may take negative values before studying a specific, non shear banding, worm like micellular system of cetylpyridinium chloride and sodium salicylate. We find that, using a weakly non-linear analysis (in which the model parameters are rate independent) the Gordon–Schowalter/Johnson–Segalman (GS/JS) model is unable to describe the superposition moduli. However, by permitting strong non-linearity (allowing the GS/JS parameters to become shear rate dependent), the superposition moduli, at all rates studied, are described well by the model. Based on this strongly non-linear analysis, the shear rate dependency of the GS/JS ‘slip parameter’, a, suggests that the onset of shear thinning in the specific worm-like micellular system studied herein is driven by a combination of microstructural modification and a transition from rotation dominated (as in the corotational Jeffreys model) to shear dominated (as in the Oldroyd-B model) deformation of the microstructural elements.

Antimicrobial cetylpyridinium chloride causes functional inhibition of mitochondria as potently as canonical mitotoxicants, nanostructural disruption of mitochondria, and mitochondrial Ca2+ efflux in living rodent and primary human cells

People are exposed to high concentrations of antibacterial agent cetylpyridinium chloride (CPC) via food and personal care products, despite little published information regarding CPC effects on eukaryotes. Here, we show that low-micromolar CPC exposure, which does not cause cell death, inhibits mitochondrial ATP production in primary human keratinocytes, mouse NIH-3T3 fibroblasts, and rat RBL-2H3 immune mast cells. ATP inhibition via CPC (EC50 1.7 μM) is nearly as potent as that caused by canonical mitotoxicant CCCP (EC50 1.2 μM). CPC inhibition of oxygen consumption rate (OCR) tracks with that of ATP: OCR is halved due to 1.75 μM CPC in RBL-2H3 cells and 1.25 μM in primary human keratinocytes. Mitochondrial [Ca2+] changes can cause mitochondrial dysfunction. Here we show that CPC causes mitochondrial Ca2+ efflux from mast cells via an ATP-inhibition mechanism. Using super-resolution microscopy (fluorescence photoactivation localization) in live cells, we have discovered that CPC causes mitochondrial nanostructural defects in live cells within 60 min, including the formation of spherical structures with donut-like cross section. This work reveals CPC as a mitotoxicant despite widespread use, highlighting the importance of further research into its toxicological safety.

Self-assembled C-Ag hybrid nanoparticle on nanoporous GaN enabled ultra-high enhancement factor SERS sensor for sensitive thiram detection

Considering pesticide residues cause significant harm to public health and the environment, developing a simple, sensitive, and reliable approach to pesticide residue detection to address this issue is necessary. In this study, an ultrasensitive and reliable surface-enhanced Raman scattering (SERS) sensor was developed using cetylpyridinium chloride as a protecting and reducing agent for the in situ synthesis and self-assembly of C-Ag nanoparticles on nanoporous GaN for the quantitative detection of thiram. A systematic investigation of the performance of the SERS sensor revealed that the SERS sensor delivered a limit of detection (LOD) of 10−14 M and an enhancement factor of up to 1.80 × 1011 with reasonable uniformity and reproducibility, with the stability of the SERS sensor demonstrated via long-term storage for up to 22 weeks in air. The enhancement mechanism of the SERS sensor was verified using a finite-difference time-domain simulation. The SERS sensor successfully detected thiram in real samples with an LOD of 10−10 M. Hence, this study provides an effective platform for monitoring food safety and the environment.

The effect of local use of etiotropic drugs on the oropharyngeal microbiota in children with acute respiratory infection

Introduction. The microbiota of the oral cavity and oropharynx, actively interacts with the epithelium of the mucous membrane and the immune system, creates antagonistic conditions for the growth and reproduction of pathogens. Microbiocenosis-preserving therapy can provide conditions for maintaining colonization resistance and reduce the likelihood of adhesion of respiratory viruses.Aim. To evaluate the effect of local use of various antimicrobial drugs on the microbiota of the oropharyngeal mucosa in children with acute respiratory infection.Materials and methods. 120 children (5–10 years old) with acute respiratory infection were divided into three groups, in which they were used as part of complex therapy: in group 1st – hexetidine-containing aerosol, in group 2nd – a children’s spray containing gramicidin S and cetylpyridinium chloride, in the 3rd – 0.01% solution of benzyldimethyl-myristoylamino-propylammonium. On the 1st and 12th days of observation, participants had a throat swab taken to study the state of the oropharyngeal microbiota using 16S rRNA sequencing. The results obtained were compared with those of healthy peers.Results. According to sequencing data, the microbiota of participants in all groups before treatment differed from the microbiota of healthy peers in terms of alpha and beta diversity, as well as in the results obtained by the nearest balance method. Local use of antiseptic drugs influenced the microbiota at the level of species and genera of microorganisms. After treatment in the 2nd group, in contrast to the 1st and 3rd, statistically significant changes in the balances at the level of microorganism species were revealed towards the indicators of healthy peers.Conclusions. A combined drug containing cetylpyritinium chloride and the bacteriocin-like antimicrobial peptide gramicidin S demonstrated no negative effect on commensal microbiota and contributed to the stabilization of the regional microbiota.

Exploring the Effect of Cetylpyridinium Chloride Addition on the Antibacterial Activity and Surface Hardness of Resin-Based Dental Composites.

The aim of this study was to evaluate the effect of cetylpyridinium chloride (CPC) addition on the antibacterial and surface hardness characteristics of two commercial resin-based dental composites (RBDCs). A total of two hundred and seventy (n = 270) specimens from Filtek Z250 Universal and Filtek Z350 XT flowable RBDCs were fabricated with the addition of CPC at 2 %wt and 4 %wt concentrations to assess their antibacterial activity using the agar diffusion test and direct contact inhibition test, and their surface hardness using the Vickers microhardness test after 1 day, 30 days, and 90 days of aging. A surface morphology analysis of the specimens was performed using a scanning electron microscope (SEM). The RBDCs that contained 2 %wt and 4 %wt CPC demonstrated significant antibacterial activity against Streptococcus mutans up to 90 days, with the highest activity observed for the 4 %wt concentration. Nevertheless, there was a reduction in antibacterial effectiveness over time. Moreover, compared to the control (0 %wt) and 2 %wt CPC groups, the universal RBDCs containing 4 %wt CPC exhibited a notable decrease in surface hardness, while all groups showed a decline in hardness over time. In conclusion, the satisfactory combination of the antibacterial effect and surface hardness property of RBDCs was revealed with the addition of a 2 %wt CPC concentration.

Study of Anti-Corrosion Properties of Sodium Dodecyl Sulphate and Cetyl Pyridinium Chloride

Surfactant is a surface-active agent. Surfactants have both hydrophilic (water-attracting) and hydrophobic (water-repelling) portions in their molecular structure, effective inhibitors for the protection of mild steel in an acidic medium, the weight loss methods were used at lab temperature to evaluate the effect of surfactant cetyl pyridinium chloride (CPC) and sodium dodecyl sulfate (SDS) on the corrosion protection behavior of Mild steel in 0.5 M H2SO4 solution. Inhibition efficiency, weight loss, corrosion rate, and surface coverage area of Mild steel in different concentrations of surfactant were studied. The results showed that the Inhibition efficiency of cetyl pyridinium chloride is 99.86%, which is greater than that of sodium dodecyl sulfate (99.85%) in the presence of 0.5 M H2SO4.

Cetylpyridinium chloride and chlorhexidine show antiviral activity against Influenza A virus and Respiratory Syncytial virus in vitro.

The oral cavity is the site of entry and replication for many respiratory viruses. Furthermore, it is the source of droplets and aerosols that facilitate viral transmission. It is thought that appropriate oral hygiene that alters viral infectivity might reduce the spread of respiratory viruses and contribute to infection control. Here, we analyzed the antiviral activity of cetylpyridinium chloride (CPC), chlorhexidine (CHX), and three commercial CPC and CHX-containing mouthwash preparations against the Influenza A virus and the Respiratory syncytial virus. To do so the aforementioned compounds and preparations were incubated with the Influenza A virus or with the Respiratory syncytial virus. Next, we analyzed the viability of the treated viral particles. Our results indicate that CPC and CHX decrease the infectivity of both the Influenza A virus and the Respiratory Syncytial virus in vitro between 90 and 99.9% depending on the concentration. Likewise, CPC and CHX-containing mouthwash preparations were up to 99.99% effective in decreasing the viral viability of both the Influenza A virus and the Respiratory syncytial virus in vitro. The use of a mouthwash containing CPC or CHX alone or in combination might represent a cost-effective measure to limit infection and spread of enveloped respiratory viruses infecting the oral cavity, aiding in reducing viral transmission. Our findings may stimulate future clinical studies to evaluate the effects of CPC and CHX in reducing viral respiratory transmissions.

Mechanism of surfactant interactions with feline coronavirus: A physical chemistry perspective

HypothesisSurfactants are inexpensive chemicals with promising applications in virus inactivation, particularly for enveloped viruses. Yet, the detailed mechanisms by which surfactants deactivate coronaviruses remain underexplored. This study delves into the virucidal mechanisms of various surfactants on Feline Coronavirus (FCoV) and their potential applications against more pathogenic coronaviruses. ExperimentsBy integrating virucidal activity assays with fluorescence spectroscopy, dynamic light scattering and laser Doppler electrophoresis, alongside liposome permeability experiments, we have analyzed the effects of non-ionic and ionic surfactants on viral activity. FindingsThe non-ionic surfactant octaethylene glycol monodecyl ether (C10EO8) inactivates the virus by disrupting the lipid envelope, whereas ionic surfactants like Sodium Dodecyl Sulfate and Cetylpyridinium Chloride predominantly affect the spike proteins, with their impact on the viral membrane being hampered by kinetic and thermodynamic constraints. FCoV served as a safe model for studying virucidal activity, offering a faster alternative to traditional virucidal assays. The study demonstrates that physicochemical techniques can expedite the screening of virucidal compounds, contributing to the design of effective disinfectant formulations. Our results not only highlight the critical role of surfactant-virus interactions but also contribute to strategic advancements in public health measures for future pandemic containment and the ongoing challenge of antimicrobial resistance.

Removal of perfluoroalkyl acids from aqueous media by surfactant-modified clinoptilolites.

Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are environmentally persistent, bioaccumulating, and toxic compounds that have attracted global attention. It is challenging to reduce the residual concentrations of these compounds to safe discharge limits. In this study, batch experiments were performed to evaluate natural clinoptilolite and clinoptilolites modified (MC) with cetylpyridinium chloride (CPC-MC), didodecyldimethylammonium bromide (DDAB-MC), hexadecyltrimethylammonium bromide (HDTMA-MC), and tetramethylammonium chloride (TMA-MC) as cost-effective aqueous PFAS adsorbents. The removal capacities of the adsorbents for the majority of the PFASs decreased in the following order: DDAB-MC > CPC-MC ≫ modified natural clinoptilolite with hexadecyltrimethyl ammonium bromide (HDTMA-MC) ≫ modified natural clinoptilolite with tetramethylammonium chloride (TMA-MC) ≈ natural clinoptilolite modified with NaCl (NC). In particular, CPC-MC and DDAB-MC reduced PFASs concentration in 50μg/L by up to 98% for perfluorooctane sulphonate. Within 30min, CPC-MC (30.5μg/L) and DDAB-MC (32.1μg/L) met the PFOS water quality criterion of 36μg/L in inland surface waters. Both adsorbents met this criterion at the highest solution volume (40mL) and 0.125g/L (solid-to-liquid ratio of 1:8). PFASs with short hydrocarbon chains competed more for adsorption. PFASs with sulphonate functional groups were also adsorbed more than carboxyl groups in single- and multi-PFAS solutions. The modified surfaces of clinoptilolites controlled PFAS adsorption through hydrophobic and electrostatic interactions. PFAS removal with surfactant-modified clinoptilolites is cost-effective and protects aquatic environments by using surplus natural materials.

Antimicrobial and antitumor activities of an alginate-based membrane loaded with bismuth nanoparticles and cetylpyridinium chloride.

To evaluate the antitumor and antimicrobial properties of an alginate-based membrane (ABM) loaded with bismuth lipophilic nanoparticles (BisBAL NPs) and cetylpyridinium chloride (CPC) on clinically isolated bacteria and a pancreatic cancer cell line. The BisBAL NP-CPC ABM was characterized using optical and scanning electron microscopy (SEM). The antimicrobial potential was measured using the disk-diffusion assay, and antibiofilm activity was determined through the live/dead assay and fluorescence microscopy. The antitumor activity was analyzed on the pancreatic cell line (Panc 03.27) using the MTT assay and live/dead assay with fluorescence microscopy. After a 24-h exposure (37°C, aerobic conditions), 5 µM BisBAL NP reduced the growth of K. pneumoniae by 77.9%, while 2.5 µM BisBAL NP inhibited the growth of Salmonella, E. faecalis and E. faecium by 82.9%, 82.6%, and 78%, respectively (p < 0.0001). The BisBAL NPs-CPC ABM (at a ratio of 10:1; 500 and 50 µM, respectively) inhibited the growth of all isolated bacteria, producing inhibition halos of 9.5, 11.2, 7, and 10.3 mm for K. pneumoniae, Salmonella, E. faecalis, and E. faecium, respectively, in contrast to the 6.5, 9.5, 8.5, and 9.8 mm obtained with 100 µM ceftriaxone (p < 0.0001). The BisBAL NPs-CPC ABM also reduced bacterial biofilms, with 81.4%, 74.5%, 97.1%, and 79.5% inhibition for K. pneumoniae, E. faecium, E. faecalis, and Salmonella, respectively. Furthermore, the BisBAL NPs-CPC ABM decreased Panc 03.27 cell growth by 76%, compared to 18% for drug-free ABM. GEM-ABM reduced tumoral growth by 73%. The live/dead assay confirmed that BisBAL NPs-CPC-ABM and GEM-ABM were cytotoxic for the turmoral Panc 03.27 cells. An alginate-based membrane loaded with BisBAL NP and CPC exhibits dual antimicrobial and antitumoral efficacy. Therefore, it could be applied in cancer treatment and to diminish the occurrence of surgical site infections.

In Vitro Assessment of Antifungal and Antibiofilm Efficacy of Commercial Mouthwashes against Candida albicans.

Candida albicans is the most critical fungus causing oral mycosis. Many mouthwashes contain antimicrobial substances, including antifungal agents. This study aimed to investigate the in vitro activity of 15 commercial mouthwashes against 12 strains of C. albicans. The minimal inhibitory concentrations (MICs), minimal fungicidal concentrations (MFCs), and anti-biofilm activity were studied. MICs were determined by the micro-dilution method using 96-well plates, and MFCs were determined by culturing MIC suspensions on Sabouraud dextrose agar. Anti-biofilm activity was evaluated using the crystal violet method. The mouthwashes containing octenidine dihydrochloride (OCT; mean MICs 0.09-0.1%), chlorhexidine digluconate (CHX; MIC 0.12%), and CHX with cetylpyridinium chloride (CPC; MIC 0.13%) exhibited the best activity against C. albicans. The active compound antifungal concentrations were 0.5-0.9 µg/mL for OCT products and 1.1-2.4 µg/mL for CHX rinses. For mouthwashes with CHX + CPC, concentrations were 1.56 µg/mL and 0.65 µg/mL, respectively. Products with polyaminopropyl biguanide (polyhexanide, PHMB; MIC 1.89%) or benzalkonium chloride (BAC; MIC 6.38%) also showed good anti-Candida action. In biofilm reduction studies, mouthwashes with OCT demonstrated the most substantial effect (47-51.1%). Products with CHX (32.1-41.7%), PHMB (38.6%), BAC (35.7%), Scutellaria extract (35.6%), and fluorides + essential oils (33.2%) exhibited moderate antibiofilm activity. The paper also provides an overview of the side effects of CHX, CPC, and OCT. Considering the in vitro activity against Candida albicans, it can be inferred that, clinically, mouthwashes containing OCT are likely to offer the highest effectiveness. Meanwhile, products containing CHX, PHMB, or BAC can be considered as promising alternatives.