Effect of Lipophilic Bismuth Nanoparticles on Erythrocytes

Lipophilic bismuth dimercaptopropanol nanoparticles (BisBAL NPs) have a very important antimicrobial activity; however their effect on human cells or tissues has not been completely studied. Undesirable effects of bismuth include anemia which could result from suicidal erythrocyte death or eryptosis. The objective of this research was to determine the effect of bismuth dimercaptopropanol nanoparticles on blood cells. The nanoparticles are composed of 53 nm crystallites on average and have a spherical structure, agglomerating into clusters of small nanoparticles. Based on cell viability assays and optical microscopy, cytotoxicity on erythrocytes was observed after growing with 500 and 1000 µM of BisBAL NPs for 24 h. AM Calcein was retained inside erythrocytes when they were exposed to 100 µM (or lower concentrations) of BisBAL NPs for 24 h, suggesting the absence of damage in plasmatic membrane. Genotoxic assays revealed no damage to genomic DNA of blood cells after 24 h of exposition to BisBAL NPs. Finally, 100–1000 µM of bismuth nanoparticles promotes apoptosis between blood cells after 24 h of incubation. Hence BisBAL NPs at concentrations lower than 100 µM do not cause damage on blood cells; they could potentially be used by humans without affecting erythrocytes and leukocytes

In vitro evaluation of the antitumor effect of bismuth lipophilic nanoparticles (BisBAL NPs) on breast cancer cells

Aim: The objective of this study was to evaluate the antitumor activity of lipophilic bismuth nanoparticles (BisBAL NPs) on breast cancer cells. Materials and methods: The effect of varying concentrations of BisBAL NPs was evaluated on human MCF-7 breast cancer cells and on MCF-10A fibrocystic mammary epitheliocytes as noncancer control cells. Cell viability was evaluated with the MTT assay, plasma membrane integrity was analyzed with the calcein AM assay, genotoxicity with the comet assay, and apoptosis with the Annexin V/7-AAD assay. Results: BisBAL NPs were spherical in shape (average diameter, 28 nm) and agglomerated into dense electronic clusters. BisBAL NP induced a dose-dependent growth inhibition. Most importantly, growth inhibition was higher for MCF-7 cells than for MCF-10A cells. At 1 µM BisBAL NP, MCF-7 growth inhibition was 51%, while it was 11% for MCF-10A; at 25 µM BisBAL NP, the growth inhibition was 81% for MCF-7 and 24% for MCF-10A. With respect to mechanisms of action, a 24-hour exposure of 10 and 100 µM BisBAL NP caused loss of cell membrane integrity and fragmentation of tumor cell DNA. BisBAL NPs at 10 µM were genotoxic to and caused apoptosis of breast cancer cells. Conclusion: BisBAL NP-induced growth inhibition is dose dependent, and breast cancer cells are more vulnerable than noncancer breast cells. The mechanism of action of BisBAL NPs may include loss of plasma membrane integrity and a genotoxic effect on the genomic DNA of breast cancer cells. Keywords: antitumor activity, bismuth nanoparticles, breast cancer, chemotherapy, cytotoxicit

Antimicrobial potential of AH Plus supplemented with bismuth lipophilic nanoparticles on E. faecalis isolated from clinical isolates

The objective of this study was to determine the antimicrobial potential of AH plus supplemented with bismuth lipophilic nanoparticles (BisBAL NPs) on the growth of Enterococcus faecalis isolated from patients with endodontic infections. BisBAL NPs, synthesized with the colloidal method, were characterized, in its pure form or AH Plus-absorbed, by energy-dispersive X-ray spectroscopy and scanning electron microscopy (EDS-SEM). Antimicrobial activity was evaluated with disc diffusion assays, and antibiofilm activity with fluorescence microscopy. BisBAL NP-supplemented AH Plus had a 4.9 times higher antimicrobial activity than AH Plus alone ( p = 0.0001). In contrast to AH Plus alone, AH Plus supplemented with BisBAL NP inhibited E. faecalis biofilm formation. The sealing properties of AH plus were not modified by the incorporation of BisBAL NPs, which was demonstrated by a 12-day split-chamber leakage assay with daily inoculation, which was used to evaluate the possible filtration of E. faecalis . Finally, BisBAL NP-supplemented AH plus-BisBAL NPs was not cytotoxic for cultured human gingival fibroblasts. Their viability was 83.7% to 89.9% after a 24-h exposure to AH Plus containing 50 and 10 µM BisBAL NP, respectively. In conclusion, BisBAL NP-supplemented AH Plus constitutes an innovative nanomaterial to prevent re-infection in endodontic patients without cytotoxic effects

Cumulative antitumor effect of bismuth lipophilic nanoparticles and cetylpyridinium chloride in inhibiting the growth of lung cancer

Objective: To determine the combined antitumor effect of bismuth lipophilic nanoparticles (BisBAL NP) and cetylpyridinium chloride (CPC) on human lung tumor cells. Material and methods: The human lung tumor cells A549 were exposed to 1–100 µM BisBAL NP or CPC, either separately or in a 1:1 combination. Cell viability was measured with the PrestoBlue assay, the LIVE/DEAD assay, and fluorescence microscopy. The integrity and morphology of cellular microtubules were analyzed by immunofluorescence. Results: A 24-h exposure to 1 µM solutions reduced A549 growth with 21.5% for BisBAL NP, 70.5% for CPC, and 92.4% for the combination ( p < 0.0001), while a 50 µM BisBAL NP/CPC mixture inhibited cell growth with 99% ( p < 0.0001). BisBAL NP-curcumin conjugates were internalized within 30 min of exposure and could be traced within the nucleus of tumor cells within 2 h. BisBAL NP, but not CPC, interfered with microtubule organization, thus interrupting cell replication, similar to the action mechanism of docetaxel. Conclusion: The growth inhibition of A549 human tumor cells by BisBAL NP and CPC was cumulative as of 1 µM. The BisBAL NP/CPC combination may constitute an innovative and cost-effective alternative for treating human lung cancer

Fluid mechanics and particle transport in a channel with one porous wall: Application to membrane filtration

Fluid mechanics of a channel with one porous wall was studied from first principles as the initial step towards understanding polarization phenomena in membrane modules. A regular perturbation method was used to solve the steady-state Navier-Stokes equations for an incompressible, constant property fluid in two dimensions with uniform suction and slip at the permeable boundary. The effects of solute and hydrodynamic parameters on concentration polarization during potable water treatment applications are investigated numerically. Inertia dominated and permeation drag dominated particle transport is discussed. Experimentally determined residence time distributions of particles in a microporous channel are interpreted in the light of inertial and permeation forces. Inertial lift theory is shown to predict initial particle transport. Experimentally observed long trailing edges in particle residence time distributions indicate the importance of other transport mechanisms even in dilute suspension mechanics. It is seen that inertial effects are negligible under conditions typical of microfiltration

Data for JGR2019JD030792

Airborne particulate matter mass and elemental concentration data from Housto

Simplified Analysis Of Contaminant Rejection During Ground- And Surface Water Nanofiltration Under The Information Collection Rule

A simple, closed-form analytical expression based on the homogenous solution diffusion model is derived for contaminant removal during nanofiltration (NF) of ground and surface water. Solute permeation and back-diffusion coefficients were used as fitting parameters to model rejection characteristics of four thin-film composite NF membranes under conditions typical of drinking water NF. Nonlinear fits of the model to experimental data suggests that the United States Environmental Protection Agency\u27s (USEPA)\u27s Information Collection Rule protocol for bench-scale studies could be improved to obtain greater precision of the mass transfer coefficients. The model was found to fit rejection data for several water treatment contaminants including total organic carbon, precursors to total organic halide, four trihalomethanes and nine haloacetic acids containing chlorine and bromine, calcium and total hardness, alkalinity and conductivity. The simplified approach to mass transfer calculations from multi-solute systems suggests that feed water recovery has a stronger influence on contaminant rejection than permeate flux. Evidence for coupled transport of divalent inorganic ions is also presented. Even though the model developed does not account for ion coupling and cannot be applied in a purely predictive mode, it can assist in the better design and interpretation of data obtained from site-specific pilot-scale water treatment NF studies conducted in support of plant design. Copyright © 2001 Elsevier Science Ltd