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Search for "pH" in Full Text gives 698 result(s) in Beilstein Journal of Nanotechnology. Showing first 200.
Therapeutic effect of F127-folate@PLGA/CHL/IR780 nanoparticles on folate receptor-expressing cancer cells
Beilstein J. Nanotechnol. 2024, 15, 954–964, doi:10.3762/bjnano.15.78
- content in the formulation was determined according to Drug release from nanoparticles The F127-folate@PLGA/CHL/IR780 were kept in diluted 0.1× PBS (NaCl 13.7 mM, KCl 0.27 mM, NaH2PO4 1 mM, and KHPO4 0.18 mM) and incubated at 37 °C for various time points, (24, 48, 72, and 168 h) at 37 °C at pH 7.4 and
- pH 5.4. After that, the nanoparticles were centrifuged at 12,000 rpm, and the pellets were collected and freeze-dried. The drugs that remained in the nanoparticle were determined as described above. Cell culture The human breast carcinoma MCF7 cell line, the human hepatoma HepG2 cell line, and the
- ). In order to mimic the conditions of drug release in vitro, the experiments were performed at 37 °C at pH 7.4 and pH 5.4. pH 7.4 represents the pH of physiological fluids in the body, while pH 5.4 is the pH value of the endosome. The CHL release was obtained by estimating the remaining CHL in the
A review on the structural characterization of nanomaterials for nano-QSAR models
Beilstein J. Nanotechnol. 2024, 15, 854–866, doi:10.3762/bjnano.15.71
- measured in a test medium or in different media, such as water at a specific pH or purity level [15][64][77]. A further step, proposed as an example of combining preexisting structure–activity predictive models in networks, is the prediction of the zeta potential in the relevant medium using a model that
- group the data into categories [60]. Related measures are the isoelectric point, which corresponds to the pH at which a nanoparticle suspension has zero zeta potential [15][17], the surface charge [31][36][63], the conductivity [77], and the electrophoretic mobility [77]. Magnetic properties are also
- indicate the absence or presence of a certain condition such as centrifugation, stirring, sonication, dispersion, or presence of additives [17][39][65][87]. Numerical descriptors used to encode the test environments include the ionic strength [17], the amount of organic matter [17], and the pH value. More
Electrospun polysuccinimide scaffolds containing different salts as potential wound dressing material
Beilstein J. Nanotechnol. 2024, 15, 781–796, doi:10.3762/bjnano.15.65
- pellet was filtered and washed using a vacuum filter to remove the phosphoric acid catalyst and the unreacted ʟ-aspartic acid monomeric molecules. Then, the pellet was mixed in distilled water for 10 min. This step was repeated until the pH of the filtrate changed from acidic to neutral. Finally, the PSI
- conductivity of the solution was determined with the SevenCompact Duo S213 Benchtop pH/mV/Conductivity Meter Cond Sensor InLab® 710 (Mettler Toledo, USA) and the viscosity with the Sine-wave Vibro Viscometer SV-10 (A&D Company, Limited, Japan). The conductivity and viscosity values of the solutions are in the
- S213 Benchtop pH/mV/Conductivity Meter; Cond Sensor InLab® 710, Mettler Toledo, USA). The salt-containing scaffolds were wrapped into silk paper and dropped into 20 mL of distilled water to investigate how the salts can be dissolved from them. The solutions were stirred at 100 rpm such that the salt
Green synthesis of biomass-derived carbon quantum dots for photocatalytic degradation of methylene blue
Beilstein J. Nanotechnol. 2024, 15, 755–766, doi:10.3762/bjnano.15.63
- of MB in aqueous media. The tests were separately conducted using sunlight and incandescent light (tungsten halogen lamp, 40 W). Previous to exposure, the reaction mixture was kept under vigorous stirring in the absence of light for 20 min to discard any adsorption effect. On the other hand, the pH
- value of the reaction mixture was kept constant during the test (pH 7). To initiate the catalytic process, each CQD sample was individually applied to the degradation of the MB dye. The UV–vis absorption spectrum of the dye was monitored using a spectrophotometer (Thermo Scientific Evolution model 220
Effect of repeating hydrothermal growth processes and rapid thermal annealing on CuO thin film properties
Beilstein J. Nanotechnol. 2024, 15, 743–754, doi:10.3762/bjnano.15.62
- (Chempur) with a concentration of Cu(II) ions of 1 mM was prepared. The mixture was then precipitated by adding NaOH until a pH of 6.5 was attained. Subsequently, the so-prepared solution along with the substrate was placed in a reaction vessel and uniformly heated utilizing an induction cooker (heating
Simultaneous electrochemical determination of uric acid and hypoxanthine at a TiO2/graphene quantum dot-modified electrode
Beilstein J. Nanotechnol. 2024, 15, 719–732, doi:10.3762/bjnano.15.60
- with 0.1 M HCl and distilled water until a supernatant with neutral pH was obtained. The solid was dried at 80 °C for 2 h. This product was then mixed with 30 mL of H2O2 (35%, d = 1.11 g·cm3) at 90 °C under magnetic stirring for 1 h to obtain a clear yellow solution of peroxo titanium complexes. The
- electrode (GCE, 3 mm diameter), a platinum wire auxiliary electrode, and a Ag/AgCl reference electrode was used. Electrolyte solutions were prepared using doubly distilled water. Britton–Robinson (BR) buffer solutions with pH between 2 and 6 were prepared by mixing boric acid solution, phosphoric acid
- temperature. The urine samples for electrochemical measurement were prepared by first diluting 1 mL urine to 20 mL with distilled water. 1.5 mL of this urine solution was added to 2 mL of 0.25 M pH 3 buffer and was diluted to 10 mL with distilled water in an electrolysis cell. The solution was spiked with 10
Exfoliation of titanium nitride using a non-thermal plasma process
Beilstein J. Nanotechnol. 2024, 15, 631–637, doi:10.3762/bjnano.15.53
- electrostatically driven exfoliation of WO3 powder using bovine serum albumin as an exfoliating agent at pH 4 [8]. Subsequently, in 2018, Balan et al. [9] achieved the synthesis of hematene, a n-vdW 2D material, from natural iron ore hematite (α-Fe2O3) using liquid exfoliation. Unlike hematite, hematene exhibited
Comparative analysis of the ultrastructure and adhesive secretion pathways of different smooth attachment pads of the stick insect Medauroidea extradentata (Phasmatodea)
Beilstein J. Nanotechnol. 2024, 15, 612–630, doi:10.3762/bjnano.15.52
- tarsomeres were fixed in 2.5% glutaraldehyde in (pH 7.4) phosphate-buffered saline (PBS) for 24 h, washed two times in PBS for 30 min each, fixed in 1% aqueous OsO4 for 1 h, and washed two times in double-distilled water, for 30 min each. After fixation, the samples were dehydrated using an ascending ethanol
Radiofrequency enhances drug release from responsive nanoflowers for hepatocellular carcinoma therapy
Beilstein J. Nanotechnol. 2024, 15, 569–579, doi:10.3762/bjnano.15.49
- been developed based on the abnormal physiological signals in the tumor microenvironment (TME), such as a low pH, high glutathione (GSH) levels, hypoxia, and the expression of specific enzymes [21]. Such intelligent nanoparticles (NPs) have successfully improved the solubility and distribution of CUR
- degrading MnO2 to release Mn2+ and lysing the CUR layer to release CUR. Mn2+ was completely released under the simulated TME condition by RF heating to 41 ± 1 °C for 20 min (Figure 4b). Up to 80% of the Mn2+ was released without RF heating. Additionally, only 7.3% of the Mn2+ was released at pH 7.4, but
- this percentage increased to 42% at pH 5.0 (Figure 4a). These results indicate that RF heating enhances degradation of NFs. Due to their structure, CUR-Fe@MnO2 NFs efficiently increased the drug loading efficiency (DLE) of CUR and improved its stability. The drug encapsulation efficiency (DEE) and DLE
Cholesterol nanoarchaeosomes for alendronate targeted delivery as an anti-endothelial dysfunction agent
Beilstein J. Nanotechnol. 2024, 15, 517–534, doi:10.3762/bjnano.15.46
- that aim, blends of lipids were dissolved in chloroform/methanol 1:1 v/v, and the solvents were rotary-evaporated until complete removal. The lipid films were flushed with N2 and hydrated with Tris buffer (10 mM Tris-HCl buffer pH 7.4 with NaCl 0.9% w/w) to obtain the void nanovesicles or 14 mg/mL ALN
- PBS and incubated for 24 h in RPMI medium with 5% SFB. Then 5 μL of 5 mg/mL MTT solution was added to each well. After 4 h of incubation, 90 μL of DMSO and 60 μL of SDS lysis solution (0.3 g/mL SDS pH 1.7) were added to each well and shaken in an orbital shaker at 120 rpm in the darkness for 15 min
Photocatalytic degradation of methylene blue under visible light by cobalt ferrite nanoparticles/graphene quantum dots
Beilstein J. Nanotechnol. 2024, 15, 475–489, doi:10.3762/bjnano.15.43
- the supernatant, the MB concentration was determined via absorption spectroscopy at a wavelength of 664 nm. The photochemical degradation efficiency of MB was calculated according to formula where C0 and Ct are the MB concentration at the beginning and at time t, respectively. Effect of pH value The
- CoFe2O4/GQDs composite material was placed in flasks sealed with aluminium foil and containing 20 mL of 10 ppm MB solution at pH 3–11, adjusted with 0.01 M HCl or 0.01 M NaOH. After 60 min of adsorption and photodegradation, the tubes were placed in a photocatalytic cabinet for illumination for 120 min
- heterojunctions limit the recombination of photo-induced electron–hole pairs and, thus, enhance catalytic decolourisation. Therefore, the CF/GQDs-200 sample was selected for further studies. The point of zero charge (pzc) of CF/GQDs-200 obtained by the pH drift method is 6.6 (see the inset of Figure 7b
Fabrication of nanocrystal forms of ᴅ-cycloserine and their application for transdermal and enteric drug delivery systems
Beilstein J. Nanotechnol. 2024, 15, 465–474, doi:10.3762/bjnano.15.42
- adjust the pH value (pH 7) of this formulation. Formulation Test 3: 20 mg of commercial DCS powder was dissolved in 0.45 mL of deionized water with 0.2 mL of PEG 400 and then mixed with 0.3 mL of corn oil (Sigma-Aldrich). A volume of 0.05 mL of 0.1 N NaOH was used to adjust the pH value (pH 7) of this
- formulation. The pH stability test of DCS We prepared two solutions for pH stability test to simulate the gastrointestinal environment: 0.1 M of an HCl solution (pH 1.2 at the stomach) (Sigma-Aldrich) and 0.1 M of phosphate buffer (pH 7.4 at the terminal ileum) (Sigma-Aldrich) [26]. Approximately 5 mg of DCS
- stability of the DCS nanocrystals used in this study were confirmed by SEM and XRPD before the experiments. The excipient compatibility study and the pH effect on DCS stability The objective of the DCS excipient compatibility test (Table 1) was to determine the best excipient, the optimal pH range, the best
Potential of a deep eutectic solvent in silver nanoparticle fabrication for antibiotic residue detection
Beilstein J. Nanotechnol. 2024, 15, 426–434, doi:10.3762/bjnano.15.38
- , 99%) were purchased from Sigma-Aldrich Co., MO, USA. Urea (CH4N2O, 99%) was obtained from ACS, Reag. Ph Eur, Merck Co., Germany, whereas glycerol (C3H8O3, 99%) was supplied by Daejung Ltd., Korea. ᴅ-glucose (C6H12O6, 99%) was purchased from Fisher Ltd., UK. The microscope glass slides (SiO2, Na2O
Classification and application of metal-based nanoantioxidants in medicine and healthcare
Beilstein J. Nanotechnol. 2024, 15, 396–415, doi:10.3762/bjnano.15.36
- microenvironments have different pH values and temperatures depending on the part and physiological status of the body. Thus, natural CAT usually suffers from low stability and is sensitively influenced by the environment. Several reports investigated the effect of pH and temperature on CAT activity as well the
- is caused by protein denaturation at high temperatures. Impressively, Co3O4 nanomaterials with different morphologies (nanoplates, nanorods, and nanocubes) exhibited the highest relative activity at very high pH (pH 9) and temperature (90 °C) [39]. Similar results were also reported for platinum
- nanoparticles whose H2O2 decomposition increased with increasing pH values (up to 11) and temperatures (up to 90 °C) [40]. The activity of natural CAT can also be improved by immobilizing it on nanomaterials. Immobilized CAT on Cu(II) nanofibers maintained approximately half of its catalytic activity after
Nanomedicines against Chagas disease: a critical review
Beilstein J. Nanotechnol. 2024, 15, 333–349, doi:10.3762/bjnano.15.30
- soluble drugs are those whose solubility is below 1 mg/mL over the physiological pH range and the BNZ solubility in distilled water or simulated gastric and enteric fluids oscillates between 0.2 and 0.4 mg/mL [29][30], BNZ is considered a poorly soluble drug. Some authors classify BNZ as a class-II drug
- strain; 466-fold lower dose than oral free BNZ with 1400 mg/kg TD), caused no detectable hepatotoxicity, and completely abrogated the weight loss. BNZ-PS, but not free BNZ, significantly reduced the number of parasites in the heart and the inflammation. In 2005, ultra-low doses of pH-sensitive
- BNZ at a 353-fold higher dose (100 mg/kg/day over 20 days: 2000 mg/kg TD [52]). The study of the effect of pH-sensitive liposomes for etanidazole delivery to CD models was discontinued, but along with BNZ-polymersomes both showed that ultralow doses of the antiparasitic drug could reduce infection and
Exploring the relationships between physiochemical properties of nanoparticles and cell damage to combat cancer growth using simple periodic table-based descriptors
Beilstein J. Nanotechnol. 2024, 15, 297–309, doi:10.3762/bjnano.15.27
- , nanoparticles can easily agglomerate into particles with larger diameter. Upon intake by organisms, depending on the pH value, these agglomerations disintegrate again becoming a source for toxins in the body [8]. The formation of agglomerated NPs depends upon the surface charge of the NPs, which is believed to
- solution. It is closely related to suspension stability and morphology. In metals, the zeta potential can be altered by altering pH, concentration, and conductivity of the components of NPs [10]. Zeta potential can provide information regarding the fate, behavior, and toxicity of NPs in the environment as
- unstable and tend to agglomerate. NPs attract negative or positive ions from the medium to build a diffusion double layer. The electronegativity of the NPs also depends on the pH value of the medium [40]. In colloidal solutions, negatively charged metal oxides decrease the zeta potential, which reflects
Vinorelbine-loaded multifunctional magnetic nanoparticles as anticancer drug delivery systems: synthesis, characterization, and in vitro release study
Beilstein J. Nanotechnol. 2024, 15, 256–269, doi:10.3762/bjnano.15.24
- cancer therapy agent, is included in the nanocomposite structure, and in vitro drug release studies under different pH conditions (pH 5.5 and 7.4) and photothermal activity at 808 nm NIR laser irradiation are investigated. The comprehensive integration of precise multifunctional nanoparticles design
- appropriate sizes exhibited controlled drug release capabilities. Thus, a controlled drug delivery system was established using VNB/PDA/Fe3O4 NPs, which exhibited high release at the tumor microenvironment pH 5.5 for potential application in cancer treatment. The impact of polymer thickness on drug release
- was also determined. Consequently, our study represents a novel contribution to the field by investigating the impact of polymer thickness on drug release, offering enhanced drug loading efficiency, improved magnetic properties, and pH-responsive drug release kinetics. Materials and Methods Materials
Design, fabrication, and characterization of kinetic-inductive force sensors for scanning probe applications
Beilstein J. Nanotechnol. 2024, 15, 242–255, doi:10.3762/bjnano.15.23
- the measured magnitude and phase response of two nominally identical devices, both with nanowire width w = 200 nm, where one device has the shunt inductance and the other does not. For a shunt with inductance Ls = 195 pH, we increase Qext by a factor of roughly twenty at the cost of a slight reduction
- temperature Tc = 9.6 K, from which we estimate the superconducting energy gap with the BCS relation Δ0 = 1.76kBTc = 1.46 meV. Using Equation 4, we find a kinetic inductance per square Lk,□ = 35 pH/□ for the 200 nm wide nanowires, corresponding to a kinetic inductance per unit length Lk/ℓ = 175 pH/μm. We
- compare this to the estimated geometric inductance per unit length, using the thin-ribbon formula [27][37] Lg ≈ (μ0/2π)ℓ ln(2ℓ/w), from which we obtain Lg/ℓ = 17 pH/μm for our 200 nm wide nanowires. The ratio of kinetic inductance to total inductance is α = Lk/(Lk + Lg) ≃ 1, meaning that we can safely
Multiscale modelling of biomolecular corona formation on metallic surfaces
Beilstein J. Nanotechnol. 2024, 15, 215–229, doi:10.3762/bjnano.15.21
- ions. The system’s pH value was maintained at a neutral level, and the NaCl salt concentration was set to 150 mM, mimicking the overall ionic strength of milk and equivalent to one salt molecule per 10 nm3. The system underwent equilibration for 1.0 ns under constant pressure conditions at 1.0 bar and
- -tempered metadynamics (AWT-MetaD) simulations, the adsorption energy was calculated at a temperature of 300 K, a pressure of 1.0 bar, and a neutral pH within the NVT ensemble. Additionally, we measured the interaction energy as a function of surface separation distance (SSD) as a collective variable
- the chosen compounds. It includes their UniProt IDs, molecular weights, charges, and the number of AAs in each protein. The charge data was determined through the PROPKA method [42][43] at a pH of 7.0. We model the lactose molecule as a pair of glucose beads; it does not possess a UniProt ID or a
Nanocarrier systems loaded with IR780, iron oxide nanoparticles and chlorambucil for cancer theragnostics
Beilstein J. Nanotechnol. 2024, 15, 180–189, doi:10.3762/bjnano.15.17
- observed for all three kinds of NPs. The release of chlorambucil was quicker at pH 5.4 than at pH 7.4 at 37 °C. The F127@NPs and F127-folate@NPs demonstrated much greater cell uptake and toxicity up to 72 h after incubation. Our in vitro results of F127@NPs and F127-folate@NPs have demonstrated the ability
- oxide NPs were synthesized using a modified coprecipitation method [13]. Firstly, 10 mmol of FeSO4·7H2O and 5 mmol of FeCl3·6H2O were dissolved in 50 mL of deionized water in a N2 atmosphere. Then, 1 M of NaOH was carefully added into the solution while swirling until the pH reached 14. Next, 1 mL of
- were performed in both 0.1× PBS (13.7 mM of NaCl, 0.27 mM of KCl, 1 mM of Na2HPO4, and 0.18 mM of KH2PO4, pH 7.4) and animal cell culture media containing DMEM and 10% FBS. Scanning electron microscopy For scanning electron microscopy (SEM) experiments, 10 μL of F127-folate@NP was loaded on the silica
Modification of graphene oxide and its effect on properties of natural rubber/graphene oxide nanocomposites
Beilstein J. Nanotechnol. 2024, 15, 168–179, doi:10.3762/bjnano.15.16
- . After 15 min, 100 mL of water was used to dilute the reaction. The powder was filtered and washed with distilled water until it had a neutral pH. The GO powder was then dispersed in water and centrifuged at 10,000 rpm for 30 min to obtain the suspended solution. The purified GO powder was collected
Assessing phytotoxicity and tolerance levels of ZnO nanoparticles on Raphanus sativus: implications for widespread adoptions
Beilstein J. Nanotechnol. 2024, 15, 115–125, doi:10.3762/bjnano.15.11
- , which affects over 49% of agricultural lands worldwide, thereby negatively affecting crops grown on calcareous and alkaline (pH > 7) soil in dry and semi-arid regions around the world [5][6]. The mean Zn content of soil ranges between 17–125 µg/g of soil while in Zn-deficient soils it is less than 10 µg
- the sample [34]. Phytotoxicity experiments on R. sativus grown in an inert solid medium The high bioavailability of Zn caused by the acidic pH (5.8–6.5) of coir might have caused the death of R. sativus grown with the application of 10,000 mg/L of ZnO NPs. This is confirmed by leaf chlorosis after 18
- ) were separately homogenized using a mortar and pestle with 10 mL of phosphate buffer (50 mM at pH 7.4). The mixture was centrifuged at 9000 rpm for 15 min at 4 °C, the supernatant was collected, and the soluble protein content was determined according to the Bradford’s method [57]. Determination of IAA
Development and characterization of potential larvicidal nanoemulsions against Aedes aegypti
Beilstein J. Nanotechnol. 2024, 15, 104–114, doi:10.3762/bjnano.15.10
- ethanol (50:50 v/v), pH 5.5. 1 mL of the formulations was used, as allowed by the Franz cell. The acceptor solution was constantly agitated at 300 rpm using mini-magnetic agitators. The temperature was maintained at 37 ± 2 °C by utilizing a circulating heating bath in the jacketed cells. The evaluation of
Study of the reusability and stability of nylon nanofibres as an antibody immobilisation surface
Beilstein J. Nanotechnol. 2024, 15, 83–94, doi:10.3762/bjnano.15.8
- efficiency. In this paper, we want to deepen the study of other key points, such as the reuse and stability of these nanofibres, in order to assess their profitability. On the one hand, the reusability of nanofibres has been studied using different stripping treatments at different pH values on the nylon
- nanofibres with well-oriented antibodies anchored by protein A/G. Our study shows that stripping with glycine buffer pH 2.5 allows the nanofibres to be reused as long as protein A/G has been previously anchored, leaving both nanofibre and protein A/G unchanged. On the other hand, we investigated the
- and Discussion Results of nanofibre reusability study High-salinity antigen/antibody (Ag/Ac) elution buffer pH 6.6 as stripping agent A commercial Ag/Ac elution buffer pH 6.6 with high salinity was able to remove almost all antibody fixed on the nanofibres through protein A/G (88.6%). The retained
Curcumin-loaded nanostructured systems for treatment of leishmaniasis: a review
Beilstein J. Nanotechnol. 2024, 15, 37–50, doi:10.3762/bjnano.15.4
- antileishmanial potential, curc has several drawbacks, such as: (i) low aqueous solubility, (ii) rapid clearance, (iii) low tissue absorption, and (iv) notable chemical degradation (neutral and alkaline pH), which severely reduces its bioavailability and hinder its clinical use [18][53][54]. Given this scenario
- combination therapy. The authors functionalized the surface of PLGA-NPs with Eudragit L30D, a polymer that provides pH-dependent drug release and significantly improved targeted action, thus increasing the efficacy of the drug [45]. Curc-E-PLGA-NPs showed spherical morphology, with a hydrodynamic mean
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