Membrane Integrity Test Research Articles

Tumor cell loaded thermosensitive hydrogel for photodynamic therapy associated tumor antigens release

Background: Immunotherapy is a powerful strategy for treating cancer and can be used to inhibit the post-surgical relapse of tumors. Methods: To achieve this, a Cell@hydrogel was developed as a template using a mixture of CT26 tumor cells and Pluronic® F-127/gelatin. Results: The proposed mixture has a solution-to-gelation functionality and vice versa. The morphology of the Cell@hydrogel was characterized by scanning electron microscopy and confocal microscopy. For photodynamic immunotherapy, the Cell@hydrogel was functionalized with Cy7 (Cy7-Cell@hydrogel) to quantify reactive oxygen species in CT26 tumor cells. Gel electrophoresis and membrane integrity tests were performed to determine the efficiency of the Cy7-Cell@hydrogel following photodynamic therapy. Conclusions: This protocol provides an alternative approach that mechanistically inhibits the post-surgical relapse of solid tumors based on immunotherapy.

Purification of proanthocyanidins from nut seeds and study on its bactericidal mechanism against Streptococcus mutans.

The aim of this study was to purify proanthocyanidins from areca nut seeds (P-AN) and to investigate the bactericidal activity and mechanism of the purified products against Streptococcus mutans. Ultra-performance liquid chromatography tandem quadrupole time-of-flight mass spectrometry, Fourier transform infrared, Matrix-assisted laser desorption/ ionization time of flight mass spectrometry (MADLI-TOF-MS), and thiolysis experiment were used for P-AN chemical analysis. Time-kill analysis and glycolytic pH drop were used to evaluate the activity of S. mutans in vitro. Meanwhile, the investigation of the bacteriostatic mechanism included membrane protein, fluidity, permeability, and integrity tests. The results showed that P-AN was a kind of proanthocyanidin mainly composed of B-type proanthocyanidins and their polymers. Moreover, MADLI-TOF-MS and thiolysis experiments demonstrated that the degree of polymerization of P-AN was 13. The time-kill analysis showed that P-AN had strong bactericidal activity against S. mutans. P-AN at minimum inhibitory concentration (MIC) concentrations was able to induce S. mutans death, while complete lethality occurred at 2 MIC. Glycolysis test showed that P-AN significantly inhibited S. mutans acid production (P<.01). The morphological changes of S. mutans were observed by scanning electron microscopy and transmission electron microscopy experiments, which indicated that P-AN destroyed the cellular structure of S. mutans. At the same time, significant changes were observed in membrane proteins, fluidity, permeability, and integrity. P-AN can effectively inhibit the activity of S. mutans. P-AN can reduce the erosion of the tooth surface by the acid of S. mutans. P-AN could break the structure of the cell membrane protein of S. mutans. P-AN could destroy the integrity of membrane, resulting in the death of S. mutans.

Performance of a SWRO membrane under variable flow conditions arising from wave powered desalination

A wave-powered desalination unit couples a wave energy converter and reverse osmosis (RO) membrane to produce fresh water from pressurized seawater. Although renewable energy technologies have been increasingly used for desalination, the concept of direct wave-powered desalination system is still at an early stage of development. One of the challenges with direct wave-powered desalination is that while reverse osmosis (RO) membranes are typically designed to operate at a constant feed flow and pressure, wave energy converter outputs in the form of hydraulic pressures and flows are typically highly variable. In this work, a RO membrane is investigated under variable feed flow conditions to determine the potential impact of such operation on membrane performance. The feed flow and pressure are varied using both a traditional sinusoidal profile and a rectified sinusoidal profile - a case more representative for wave-powered desalination. The permeate recovery and permeate salinity for both cases are compared with the equivalent time-averaged steady-state conditions. For purely sinusoidal flow, the performance of the RO membrane was similar to the equivalent steady-state flow conditions. For rectified sinusoidal flow, there is a marginal increase in permeate recovery, while a significant increase in permeate salinity is observed. In addition, a membrane integrity test was carried out after both sets of varying flow conditions. A significant change in membrane performance was detected after the test with the rectified sinusoidal flow.

Unveiling the volatile compounds and antibacterial mechanisms of action of Cupressus sempervirens L., against Bacillus subtilis and Pseudomonas aeruginosa

Cupressus sempervirens is a known traditional plant used to manage various ailments, including cancer, inflammatory and infectious diseases. In this investigation, we aimed to explore the chemical profile of Cupressus sempervirens essential oil (CSEO) as well as their antibacterial mode of action. The volatile components were characterized using gas chromatography coupled to a mass spectrometer (GC-MS). The results revealed remarkable antibacterial properties of EO derived from C. sempervirens. GC-MS analysis indicated that C. sempervirens EO characterized by δ-3-carene (47.72%), D-limonene (5.44%), β-pinene (4.36%), β-myrcene (4.02%). The oil exhibited significant inhibitory effects against a range of bacteria, including Staphylococcus aureus ATCC 29213, Bacillus subtilis ATCC 13048, Bacillus cereus (Clinical isolate), Pseudomonas aeruginosa ATCC 27853, and Escherichia coli ATCC 25922. These inhibitory effects surpassed those of conventional antibiotics. Furthermore, the EO demonstrated low minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs), indicating its bactericidal nature (MBC/MIC < 4.0). Time-kill kinetics analysis showed that CSEO was particularly effective at 2 × MIC doses, rapidly reduced viable count of B. subtilis and P. aeruginosa within 8 h. This suggests that the oil acts quickly and efficiently. The cell membrane permeability test further demonstrated the impact of CSEO on the relative conductivity of B. subtilis and P. aeruginosa, both at 2 × MIC concentrations. These observations suggest that EO disrupts the bacterial membrane, thereby influencing their growth and viability. Additionally, the cell membrane integrity test indicated that the addition of CSEO to bacterial cultures resulted in the significant release of proteins from the bacterial cells. This suggests that EO affects the structural integrity of the bacterial cells. Furthermore, the anti-biofilm assay confirmed the efficacy of CSEO as a potent anti-biofilm agent. It demonstrated the oil's ability to inhibit quorum sensing, a crucial mechanism for biofilm formation, and its competitive performance compared to the tested antibiotics.

Exploring the antibacterial mechanisms of chemically characterized essential oils from leaves and buds of Syzygium aromaticum (L.) Merr. et Perry against Staphylococcus aureus and Pseudomonas aeruginosa

Syzygium aromaticum (L.) Merr. et Perry is a medicinal plant extensively used in international pharmacopeia to treat different ailments, including infectious diseases. In this study, we designed to determine the chemical constituents of S. aromaticum essential oils extracted from leaves (CEOL) and floral buds (CEOB) and their antibacterial mechanism of action against S. aureus and P. aeruginosa. The volatile components from CEOL and CEOB were detected using gas chromatography coupled to a mass spectrometer (GC/MS). The results indicated that eugenol was the major component for both CEOL (65.75%) and CEOB (74.03%). The antibacterial findings demonstrated the potent antibacterial activity of CEOL and CEOB. These oils exhibited significant zones of inhibition against all tested bacteria, including S. aureus ATCC 29213, K. aerogenes ATCC 13048, P. aeruginosa ATCC 27853, and E. coli ATCC 25922, surpassing the effects of antibiotics. Additionally, they displayed low minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs), indicating their bactericidal nature (MBC/MIC < 4.0). Time-kill kinetics revealed that CEOB was more effective than CEOL at sub-MIC doses, eradicating S. aureus within 12 h and P. aeruginosa within 12–24 h. The cell membrane permeability test demonstrated that CEOL and CEOB treatment affected the relative conductivity of S. aureus and P. aeruginosa at both MIC and sub-MIC concentrations, indicating disruption of the bacterial membrane and influencing their growth and viability. Furthermore, the cell membrane integrity test showed that the addition of CEOL and CEOB to S. aureus and P. aeruginosa cultures led to significant protein release from the bacterial cells. The results of the anti-biofilm activity test confirmed the efficacy of S. aromaticum EOs, particularly CEOB, as potent anti-biofilm agents, suggesting its potential effect on inhibiting quorum sensing. Scanning electron microscope (SEM) microscopy further revealed significant alterations in bacterial cells treated with CEOB essential oil, including damage to the cell wall and distorted cell morphology, highlighting its impact on bacterial cell structure. Presented information suggests the use of clove EOs as natural alternatives for sustainable application in food and pharmaceutical industries.

Establishment of methods to analyze the structural and functional integrity of the quail (Coturnix coturnix japonica) sperm plasma membrane

ABSTRACT 1. The objectives of this study were to establish the use of the fluorophores Hoechst 33342 and propidium iodide for the evaluation of sperm plasma membrane integrity and to identify an adequate hypoosmotic solution for the evaluation of sperm membrane functionality in quails. 2. Sperm samples were collected from the vas deferens of nine quails. After initial evaluation, the samples were subjected to a flash-frozen assay. Three treatments with the following proportions of fresh sperm and sperm subjected to flash freezing were prepared as follows: 100:0 (T100), 50:50 (T50), and 0:100 (T0). The hypoosmotic swelling test used distilled water (0 mOsm/l) and fructose solutions (50, 100, and 200 mOsm/l). 3. Immediately after recovery, the samples showed 75.6 ± 5.0% motility with vigour of 3.7 ± 0.3 and 96.1 ± 0.5% of the sperm appeared normal. The membrane integrity test showed 62.2 ± 5.2% intact sperm at T100, 29.0 ± 4.1% at T50 and 0.1 ± 0.1% at T0. Moreover, a greater number of reactive sperm (74.7 ± 6.7%) were observed when incubated in distilled water (0 mOsm/l) in comparison to other solutions (P < 0.05). 4. The association of fluorescent probes composed of Hoechst 33342 and propidium iodide provided an efficient assessment of the integrity of the plasmatic membrane of quail spermatozoa. However, the study identified that the hypoosmotic swelling test has little predictive value regarding sperm membrane functionality in this species.

Feed efficiency improves sperm quality and viability of fertilisation in Dorper sheep

ABSTRACT The aim was to evaluate the influence of residual feed intake (RFI) on the semen characteristics of Dorper sheep after cryopreservation. Six Dorper sheep were used, classified from a population of 64 according to feed efficiency (groups of animals-positive RFI and negative RFI). The ejaculates were harvested three times a week, with a minimum interval of 48-h between collections, being seven collections per animal, totalling 42 ejaculates. Motility, plasma membrane integrity, acrosomal, mitochondrial activity and perivitelline membrane binding tests were performed. Negative RFI animals presented higher progressive motility (31.28%) than of RFI positive (25.37%). Negative and positive RFI animals present similar qualities in the assessment of plasma and acrosomal membrane integrity and mitochondrial activity, and negative RFI animals presented a higher number of membrane-bound spermatozoa than the positive RFI animals. Negative RFI animals displayed better rates of sperm motility after thawing, and are more efficient in the fertilisation in vitro. RFI did not influence the integrity of the plasma and acrosomal membrane, nor the mitochondrial activity of Dorper sheep spermatozoa after cryopreservation.

Sperm Membrane and Acrosomal Integrity Affected by using Black Currant

This study was designed in order to investigate and determine the effect of black current (Prunus cerasus) extract on semen membrane and acrosome integrity of the rams. Twelve mature healthy rams were used in this study aged between 2-3 years, kept in the animal farm of the College of Veterinary Medicine, Al-Kufa University. Semen ejaculates was collected using electro-ejaculator methods once weekly a total of 36 ejaculates were collected among the period of the study. The black current (Prunus cerasus) extract was prepared by using maceration and added to the diluted semen in five doses groups (0.25 gm/ml as G1, 0.5 gm/ml as G2, 1 gm/ml as G3, 2 gm/ml as G4, 4 gm/ml as G5) and the positive control group left without any addition. The treatment samples were evaluated under cooling for five consecutive days, the membrane integrity test was evaluated using hypo-osmotic solution and acrosome integrity was analysis using semen smear stained with eosin–nigrosin stain. The result showed that high concentration of aqueous plant extract give negative result as listed in G3, G4 and G5 in the all preservation days. As found in acrosome integrity at the 5thday of incubation showed decreased at highly significantly sequentially. We conclude that the G1 and G2 of black current extract (Prunus cerasus) should be used in chilling process as a part of artificial insemination in sheep due to its protective effect of the membrane and acrosome integrity.

Celastrol inhibits neurotoxicity induced by Cd2

Cadmium (Cd) is a common heavy metal in the environment. Cd2+ may penetrate the blood-brain barrier and produce neurotoxicity, thus inducing various neurodegenerative diseases. Celastrol is an effective component of Tripterygium wilfordii Hook. F., which has many pharmacological effects such as anti-cancer and anti-inflammatory. Here we explored the effect of celastrol on the corresponding neurotoxicity induced by Cd2+. Cell proliferation test, cell membrane integrity test, and cell morphology were observed to analyze the effect of Cd2+ on the viability of HMC3. The neurotoxicity of Cd2+ and the effect of celastrol on the corresponding neurotoxicity induced by Cd2+ were analyzed by nitric oxide (NO) test, lipid peroxidation (MDA) test, and Western blotting. When the concentration of Cd2+ reached 40 μmol/L, the inhibition rate of HMC3 cell proliferation was (57.17±8.23)% (P < 0.01, n=5), compared with the control group. The cell activity continued to reduce when the Cd2+ concentration further increased. When the concentration of Cd2+ was higher than 40 μmol/L, the cell membrane of HMC3 was significantly damaged, and the damage was dose-dependent. Upon increasing the Cd2+ concentration, the cell morphology began to change and the adhesion also became worse. Cd2+ significantly increased the amount of NO released by HMC3 cells, while celastrol effectively inhibited the NO release of HMC3 cells induced by Cd2+. Cd2+ greatly increased the release of MDA in HMC3 cells, and the level of MDA decreased rapidly upon the addition of 10-7 mol/L celastrol. Cd2+ increased the expression of p-PI3K protein, and the levels of p-PI3K protein and p-AKT protein were inhibited by the addition of celastrol (10‒7 mol/L, 10‒6 mol/L), thus preventing cell apoptosis. In conclusion, celastrol inhibits Cd2+ induced microglial cytotoxicity and plays a neuroprotective role.

The Effect of Sugarcane Water Subtitution as a Candidate Substitute for Fructose in CEP Diluent on Spermatozoa Quality of Friesian Holstein Bull during Frozen Storage

Sugarcane water contains sucrose which function as an energy source to increase ATP and motility of sprematozoa. The purpose of this study was to determine the effect of sugarcane water substitution as a candidate for fructose substitute in CEP diluent on the sperm quality of Friesian Holstein (FH) bull in frozen storage. The type of research used was experimental research with Completely Randomized Design (CRD) with 5 treatments and 4 repetitions, namely A (CEP); B (CEP without fructose + 15% sugarcane water); C (CEP without fructose + 20% sugarcane water); D (CEP without fructose + 25% sugarcane water); E (CEP without fructose + 30% sugarcane water). Parameters used were motility, viability, and membrane integrity of FH bull spermatozoa. The motility test was observed with a 400x magnification microscope. The viability test was carried out with eosin-negrosin dye and observed with a 400x magnification microscope. The membrane integrity test was carried out with HOST fluid and observed with a 400x magnification microscope. Data analysis used the Kolmogorov-Smirnov test, then the One-Way ANOVA test and Duncan’s test. The result showed that the treatment with CEP diluent had the best results in maintaining the quality of spermatozoa during frozen storage with an average motility, viability and membrane integrity of 40,11±0,41%; 46,71±0,15% and 45,88±0,77% respectively.

Genotoxicity and in vitro investigation of Gefitinib-loaded polycaprolactone fabricated nanoparticles for anticancer activity against NCI-H460 cell lines

For non-small cell lung cancer (NSCLC) treatment, a BCS class II drug, Gefitinib, was widely used. Due to poor bioavailability, uncontrollable drug release, Gefitinib witnessed side effects. To circumvent such associated problems, optimized Gefitinib encapsulated polycaprolactone (PCL) nanoparticles with three different molecular weights of PCL (average Mn∼10,000, Mn∼45,000 & Mn∼80,000) were developed using Box–Behnken design while understanding the influence of critical process parameters of the nanoparticles. For morphological characterizations, SEM, TEM, AFM were used. Hemocompatibility, platelet aggregation, and erythrocyte membrane integrity tests were used to test nanoparticles for biocompatibility; excellent biocompatibility was reported during these tests. The in-vitro drug release studies confirmed that Gefitinib-PCL10,000NPs, Gefitinib-PCL45,000NPs, and Gefitinib-PCL80,000 NPs, show significant initial burst effects, and later nanoparticles possessed zero-order kinetics. The genotoxicity of PCL nanoparticles was assessed by cytokinesis-block micronucleus (CBMN) assay, indicating DNA damage in NCI-H460 cell and micronuclei and nuclear buds’ formation. Further, reactive oxygen species studies, MTT cytotoxicity assays at 24 & 48 h, stability, in-vitro cellular uptake of optimized fluorescent Gefitinib PCL80,000NPs, and apoptosis studies were also carried out. As a result, investigating stable Gefitinib-loaded poly-caprolactone (PCL) nanoparticles could open up new research avenues, potentially lowering side effects and improving Gefitinib's profile in the treatment of NSCLC.

Performance of reverse osmosis membrane with large feed pressure fluctuations from a wave-driven desalination system

Wave-driven desalination systems are proposed water treatment systems that involve reverse osmosis of seawater powered directly by wave motion. Such a configuration would result in drastic feed pressure fluctuations. For a technology conventionally operated with a constant feed condition, the effect of these variable pressures on membrane integrity and performance is unknown. Experiments were conducted with spiral wound membranes coupled to a system capable of producing feed pressure fluctuations of more than 400 psi. Feed composition included 5, 20, and 35 g/L NaCl, and a synthetic seawater at normal and 1.5× concentration. The variable feed conditions included sine-like pressure waves swings of 200–500 and 500–900 psi with frequencies of 1.25, 7.5, and 12 waves/min, and a model-generated random waveform. Between each wave experiment we performed membrane integrity tests at 650 psi and 25 g/L NaCl feed, which showed a 7.4% drop in the membrane's water permeability coefficient, an 18.4% flux decline, and more than 99% salt rejection over 1770 h of cumulative experimental time. Analysis of permeate samples showed high salt rejection. In general, variable feed pressure had no significant deleterious effect on membrane integrity or performance.

Quality and fertility of extended boar semen after prolonged transport

The aim of this study was to analyse semen quality parameters of fresh-extended porcine semen imported from Denmark through prolonged importing regulations and transport and to analyse fertility performance in sows inseminated four days post semen collection. Semen was analysed immediately upon the arrival (4 days post collection) using computer-assisted sperm analyses (CASA), cytomorphology and flow cytometry, and sows were inseminated later the same day. The mean sperm concentration was 1718.09 ± 100.11 × 106 , with average of 1193.40 ± 90.58 × 106 motile cells (69%) and 756.04 ± 70.57 × 106 progressive motile spermatozoa (43.58%) in a dose, which was almost twice lower in value than producer certified-declared number of 2 billion of motile cells. Acrosome and sperm membrane integrity test indicated high percentage of total damaged acrosome. Mean values of semen samples analysed by sperm chromatin structure assay (SCSA) showed relatively high degree of chromatin damage. Membrane permeability test showed high percentage of sperm with damaged membrane. Prolonged transport negatively affected the sperm quality in terms of both motility and chromatin structure stability. Fertility of sows was affected by semen quality in terms of concentration and sperm motility parameters, as well as ratio of live sperm cells population with damaged acrosome.

In vitro antibacterial effect of fifth generation dentin bonding agent incorporated with nisin on Streptococcus mutans

IntroductionBacterial adherence to restorative materials such as composite resin is one of the aetiology of secondary caries. This study evaluated the antibacterial efficacy of fifth generation bonding agent (BA) modified with nisin, against Streptococcus mutans based on its growth, adherence and membrane integrity.MethodsAdhesive eluents of the experimental bonding agents were obtained using 250 μl Brain Heart Infusion (BHI) broth and the groups were control (BA with 0% Nisin), bonding agent with 1 wt% (NBA 1) and 5 wt% nisin (NBA 5). To this, 10 μl S. mutans culture was added and incubated at 37 °C. Bacterial growth was estimated by changes in optical density using spectrophotometer every 20 min for 2 h. The results were statistically analysed using one way ANOVA followed by Tukey Post Hoc test. For adherence and membrane integrity test, 10 μl of BHI supplemented with 1% sucrose and 50 μl of bacterial suspension were inoculated onto the cured specimens, and incubated for 4 h. After rinsing, 1 ml of Live/Dead BacLight bacterial viability stain was added and incubated in the dark for 15 min and observed under confocal laser scanning microscope (CLSM) for intact (green/live) and damaged (red/dead) bacterial membranes.ResultsMean optical density was significantly higher in control group at all time intervals with maximum value at 2 h (0.83 ± 0.008), while there was a concentration dependant reduction in bacterial growth with the NBA groups (0.50 ± 0.007). Correspondingly, the NBA groups showed higher amount of dead than live bacteria, while live bacteria were predominant in the control group.SignificanceAddition of an antibacterial agent nisin in dentin bonding agent may render the resin dentin interface more resistant to bacterial penetration, and adherence of cariogenic bacteria like S. mutans.

A Mechanistic Study of Drug Mass Transport from Supersaturated Solutions Across PAMPA Membranes

There is an increasing shift from dissolution testing to dissolution-permeation testing of formulations during formulation development and this has led increasing application of permeability measurements using parallel artificial membrane permeability assay (PAMPA) membranes. However, there is a lack of thorough analysis of the impact of variabilities in the PAMPA setup on the mass flow rate outcomes, particularly for complex solubility-enabling formulations. In this study, we investigated the impact of amorphous drug-rich nanodroplets, formed in supersaturated solutions by liquid-liquid phase separation, on membrane transport by measuring mass flow rate across PAMPA membranes. In addition, we explored the impact of PAMPA variants such as lipid composition, hydrophobicity and pore size of the filter support, as well as receiver sink properties on membrane mass flow rates of solutions containing amorphous nanodroplets. Filter properties and lipid composition did not show a notable influence on the mass flow rates for lipophilic molecules, while a marked impact was observed for hydrophilic molecules. High sink conditions in the receiver compartment, arising from addition of micellar surfactant, altered the membrane integrity for lipid-impregnated hydrophilic membranes. In contrast, no such effect was observed for a hydrophobic filter support. Membrane integrity tests also suggested that monitoring water transport may be an improved approach over using Lucifer yellow. Furthermore, high sink conditions in the receiver compartment resulted in an increase in the overall mass flow rate. This was due to the effect of asymmetric conditions, generated across the membrane, on mass transport kinetics. Linearity between mass flow rate and donor concentration was observed until the donor concentration reached the amorphous solubility. Above the amorphous solubility, a gradual increase in mass flow rate was observed i.e., with an increasing number of nanodroplets in the solution. This was attributed to decrease in the permeability barrier across unstirred water layer due to reduction of the concentration gradient as nanodroplets dissolved to replenish absorbed drug. Observations made in this study provide insights into the mechanisms associated with mass transport of supersaturated solutions across PAMPA membranes, which are critical for improved evaluation of enabling formulations.

Salicylic acid pre-treatment modulates Pb2+-induced DNA damage vis-à-vis oxidative stress in Allium cepa roots.

The current study investigated the putative role of salicylic acid (SA) in modulating Pb2+-induced DNA and oxidative damage in Allium cepa roots. Pb2+ exposure enhanced free radical generation and reduced DNA integrity and antioxidant machinery after 24 h; however, SA pre-treatment (for 24 h) ameliorated Pb2+ toxicity. Pb2+ exposure led to an increase in malondialdehyde (MDA) and hydrogen peroxide (H2O2) accumulation and enhanced superoxide radical and hydroxyl radical levels. SA improved the efficiency of enzymatic antioxidants (ascorbate and guaiacol peroxidases [APX, GPX], superoxide dismutases [SOD], and catalases [CAT]) at 50-μM Pb2+concentration. However, SA pre-treatment could not improve the efficiency of CAT and APX at 500 μM of Pb2+ treatment. Elevated levels of ascorbate and glutathione were observed in A. cepa roots pre-treated with SA and exposed to 50 μM Pb2+ treatment, except for oxidized glutathione. Nuclear membrane integrity test demonstrated the ameliorating effect of SA by reducing the number of dark blue-stained nuclei as compared to Pb2+ alone treatments. SA was successful in reducing DNA damage in cell exposed to higher concentration of Pb2+ (500 μM) as observed through comet assay. The study concludes that SA played a major role in enhancing defense mechanism and protecting against DNA damage by acclimatizing the plant to Pb2+-induced toxicity.

Monitoring of Membrane Integrity Based on Electrical Measurement and Deep Learning

Membrane module integrity monitoring is essential in the water treatment process. Problems such as high cost and low sensitivity limit the development of existing detection methods. An intelligent detection method for membrane integrity based on array impedance measurement is proposed in this paper. The boundary voltage data are collected in real time through the designed electrical sensor array. A deep learning algorithm is used to analyze the degree of damage of the membrane based on the collected voltage data. Membrane integrity testing experiments are conducted for different water qualities (lake water and domestic sewage) under different aeration intensities and membrane fluxes. Detection models based on a convolutional neural network (CNN) and deep neural network (DNN) are built, and the identification results are compared with those of the average voltage method. The experiments show the following: 1) For the tests based on random samples of membranes under detection, the overall sensitivities of the CNN in the lake water experiment and domestic sewage experiment reach 97.3% and 98.5%, respectively, which are significantly higher than those of the DNN method (94.1% and 93.6%) and the average voltage method (87.4% and 77.4%). 2) When the membrane process is affected by the variation in the aeration intensity and membrane flux, the CNN still has the best robustness. Hence, the new method could stably and accurately reflect the level of membrane breakage, even mild damage to the membrane, under flow disturbance.

Preparation of Celery Essential Oil-Based Nanoemulsion by Ultrasonication and Evaluation of Its Potential Anticancer and Antibacterial Activity.

IntroductionPlants have always been a significant source of natural active components with biological properties. Celery seed oil (extracted from Apium graveolens) has several potential applications, but its therapeutic uses in the form of nanoemulsion formulation need to be investigated further in order to meet the demand in cancer treatment, and to alleviate the prevailing crisis arising from increased antimicrobial resistance.MethodsThe therapeutic potential of celery seed oil was investigated through the formulation and testing of a nanoemulsion developed with Tween 80 (a non-ionic surfactant) and the utilization of an ultrasonication technique. Anticancer and apoptotic properties of the formulation were evaluated through MTT and Annexin V-FITC assays. The clonogenic assay aided in the identification of the antiproliferative properties of the formulation on oral squamous cell carcinoma. The antimicrobial study was supported by agar well diffusion assay, membrane integrity test and scanning electron microscopy.ResultsExperiments identified relevant parameters, including optimal surfactant concentration and emulsification time. GC-MS analysis identified various components in the celery oil, but not their biological activities. A sonication time of 20 min resulted in a droplet diameter of 23.4 ± 1.80 nm. The IC50 concentration of the optimal nanoemulsion formulation against SAS cells was 1.4 µL/mL. At this concentration, cell proliferation was significantly reduced through inhibition of the anchorage-independent cell growth by disrupting colony formation and inducing cell death (apoptosis) of cancer cells. The nanoemulsion was also treated with a microbial suspension of S. aureus, and displayed antibacterial properties through lipid membrane fusion, causing cytoplasmic leakage as verified through agar well diffusion and membrane permeability assays. Scanning electron microscopy revealed complete distortion of the bacterial pathogen.ConclusionThe results in this study present celery as a possible constituent for cancer therapeutics and as a candidate for aggressive, yet safe cancer treatment. The celery-based nanoemulsion has the potential to act as a key alternative to standard antibiotic therapy.

Using EEM fluorescence to characterize the membrane integrity of membrane bioreactor (MBR)

In this study, a novel method for EEM fluorescence spectra examination of the membrane integrity in MBRs was investigated. Dissolved organic matter (DOM) was measured to determine the performance of membrane retention. The sensitivity of membrane integrity tests which reported as a log reduction value (LRV) was recalculated. The results show that, two protein-like species, one humic-like species and one fulvic-like species were found in MBRs using parallel factor analysis (PARAFAC). When the membrane pore size was 0.2 μm, the majority of macromolecular protein-like species could be effectively rejected. The fluorescence regional integration (FRI) results for the tryptophan species and the aromatic protein species showed a positive correlation with the different breakage rates of fibers, the correlation coefficients were 0.980 and 0.987, respectively. In comparison with particle counting detection, EEM fluorescence spectral analysis exhibits good practicability with regards to response time and feedback accuracy. With an LRV of 4.26, it can detect the water quality and membrane integrity without having to add other substances as tracers. In addition to expanding the membrane integrity technologies, this study also provides a method for real-time membrane filtration detection and water quality analysis in MBRs.

New nanoparticles for topical ocular delivery of erythropoietin

Erythropoietin (EPO) is known for its neuroprotective and neuroregenerative properties. EPO topical ocular administration has not been tested yet and its bioavailability could be improved by mucoadhesive hydrogels. Thus, this study aimed to develop and evaluate a chitosan (CS) and hyaluronic acid (HA) nanoparticulate system for topical ocular delivery of EPO. Nanoparticles were prepared by ionotropic gelation using six different HAs (HA1-HA6), and characterized by size, zeta potential (ZP), polydispersity index (Pdi), cytotoxicity and mucoadhesion. Encapsulation efficiency and drug loading capacity were also determined. Ex vivo permeation was tested using fresh porcine corneas, scleras and conjunctivas. The permeated EPO was quantified by ELISA, and its presence in the membranes was confirmed by immunohistochemistry. Nanoparticles (NPs) presented size ≤300nm, ZP around +30mV and low Pdi (0.167-0.539) at a 1:1 CS:HA mass ratio. The most suitable HA was HA6 (300kDa - Eye), which had the best mucoadhesive properties. CS/HA6-EPO nanoformulation permeated more rapidly through porcine conjunctiva, followed by sclera and thirdly by cornea, as assessed by immunohistochemistry. All formulations were noncytotoxic on ARPE-19 and HaCaT cell lines, as evaluated by metabolic and membrane integrity tests. In conclusion, CS/HA6-EPO NPs could be a promising formulation for increasing EPO ocular bioavailability by enhancing its retention time and permeation through the different ocular membranes.