Average Hydrodynamic Diameter Research Articles

Lanthanide-Based Single-Chain Nanoparticles as "Visual" Pass/Fail Sensors of Maximum Permissible Concentration of Cu2+ Ions in Drinking Water.

The maximum permissible concentration (m.p.c.) of Cu2+ ions in drinking water, as set by the World Health Organization (WHO) is m.p.c. (Cu2+)WHO = 30 × 10-6m, whereas the US Environmental Protection Agency (EPA) establishes a more restrictive value of m.p.c. (Cu2+)EPA = 20 × 10-6m. Herein, for the first time ever,a family of m.p.c. (Cu2+) "visual" pass/fail sensors is developed based on water-soluble lanthanide-containing single-chain nanoparticles (SCNPs) exhibiting an average hydrodynamic diameter less than 10 nm. Both europium (Eu)- and terbium (Tb)-based SCNPs allow excessive Cu2+ to be readily detected in water, as indicated by the red-to-transparent and green-to-transparent changes, respectively, under UV light irradiation, occurring at 30 × 10-6m Cu2+ in both cases. Complementary, dysprosium (Dy)-based SCNPs show a yellow color-to-transparent transition under UV light irradiation at ≈15 × 10-6m Cu2+. Eu-, Tb-, and Dy-containing SCNPs prove to be selective for Cu2+ ions as they do not respond against other metal ions, such as Fe2+, Ag+, Co2+, Ba2+, Ni2+, Hg2+, Pb2+, Zn2+, Fe3+, Ca2+, Mn2+, Mg2+, or Cr3+. These new m.p.c. (Cu2+) "visual" pass/fail sensors are thoroughly characterized by a combination of techniques, including size exclusion chromatography, dynamic light scattering, inductively coupled plasma-mass spectrometry, as well as infrared, UV, and fluorescence spectroscopy.

Preparation and Characterization of Polymeric Microparticles Based on Poly(ethylene brassylate-co-squaric Acid) Loaded with Norfloxacin.

In recent years, increasing interest has been accorded to polyester-based polymer microstructures, driven by their promising potential as advanced drug delivery systems. This study presents the preparation and characterization of new polymeric microparticles based on poly(ethylene brassylate-co-squaric acid) loaded with norfloxacin, a broad-spectrum antibiotic. Polymacrolactone was synthesised in mild conditions through the emulsion polymerization of bio-based and renewable monomers, ethylene brassylate, and squaric acid. The microparticles were obtained using the precipitation technique and subsequently subjected to comprehensive characterization. The impact of the copolymer/drug ratio on various properties of the new system was systematically evaluated, confirming the structure of the copolymer and the encapsulation of norfloxacin. The microspheres are approximately spherical and predominantly homogeneously distributed. The average hydrodynamic diameter of the microparticles falls between 400 and 2000 nm, a decrease that is observed with the increase in norfloxacin content. All samples showed good encapsulation efficiency and drug loading capacity, with the highest values obtained for microparticles synthesised using an equal ratio of copolymer and drug. In vitro drug release results disclose that norfloxacin molecules are released in a sustained biphasic manner for up to 24 h. Antimicrobial activity was also studied, with samples showing very good activity against E. coli and moderate activity against S. aureus and E. faecalis. In addition, HDFA human fibroblast cell cultures demonstrated the cytocompatibility of the microparticles.

Controlled Release of Drugs from Extracellular Matrix-Derived Peptide-Based Nanovesicles through Tailored Noncovalent Interactions.

Elastin-collagen nanovesicles (ECnV) have emerged as a promising platform for drug delivery due to their tunable physicochemical properties and biocompatibility. The potential of nine distinct ECnVs to serve as drug-delivery vehicles was investigated in this study, and it was demonstrated that various small-molecule cargo (e.g., dexamethasone, methotrexate, doxorubicin) can be encapsulated in and released from a set of ECnVs, with extents of loading and rates of release dictated by the composition of the elastin domain of the ECnV and the type of cargo. Elastin-like peptides (ELPs) and collagen-like peptides (CLPs) of various compositions were produced; the secondary structure of the corresponding peptides was determined using CD, and the morphology and average hydrodynamic diameter (∼100 nm) of the ECnVs were determined using TEM and DLS. It was observed that hydrophobic drugs exhibited slower release kinetics than hydrophilic drugs, but higher drug loading was achieved for the more hydrophilic Dox. The collagen-binding ability of the ECnVs was demonstrated through a 2D collagen-binding assay, suggesting the potential for longer retention times in collagen-enriched tissues or matrices. Sustained release of drugs for up to 7 days was observed and, taken together with the collagen-binding data, demonstrates the potential of this set of ECnVs as a versatile drug delivery vehicle for longer-term drug release of a variety of cargo. This study provides important insights into the drug delivery potential of ECnVs and offers useful information for future development of ECnV-based drug delivery systems for the treatment of various diseases.

Abstract 5750: Development of prostate specific membrane antigen-targeted liposomal zinc for the treatment of prostate cancer

Abstract Introduction: Treatment choices for early-stage prostate cancer include mostly watchful waiting, radical prostatectomy, or radiation therapy, whereas for advanced cases hormone therapy followed by chemo/radiotherapy are the preferred options, despite their notable side effects. There is a need for more effective therapy with lower side effects, especially for advanced scenarios. Unlike normal epithelial prostate cells, cancerous ones show reduced zinc (Zn) levels due to ZIP1 zinc transporter downregulation. Zn deficiency allows m-aconitase to remain active, making prostate cancer cells energy efficient and grow. High levels of Zn are needed to inhibit m-aconitase, the enzyme responsible for the first reaction in the Krebs cycle. This study aims to induce energy starvation and cell death of prostate cancer cells by inhibiting m-aconitase using the prostate-specific membrane antigen (PSMA)-targeting liposomal zinc. Methods: Liposomes were prepared by standard reverse phase evaporation method with DSPC, Cholesterol and DSPE-mPEG(2000) lipids. Zinc chloride was used to load Zn+2 into liposome following passive loading method. PSMA-expressing (PC3-PIP) and PSMA-null (PC3-LUC) human prostate cancer cells were used for in vitro studies. In the cell uptake study, cells were incubated with Dil-dye labeled liposomes for 2 hours before analyzing them by microscopy and flow cytometry. For the uptake inhibition study, cells were pre-incubated with PSMA-specific peptide for 2 hours before incubation with liposomes. Cytotoxicity studies were performed with PSMA-targeting Zn-loaded liposomes in PC3-PIP cells. Results: We conjugated the PSMA-specific peptide and control peptide (ASP3) with DSPE-PEG(3400)-NHS, and used them at various amounts (1 to 4 mol% of total lipid) to prepare Zn-loaded PSMA-targeting liposomes (TL) and control liposomes (CL), respectively. The average hydrodynamic diameter of all the liposomes was 120 to 130 nm, and zeta potential ranged from -16 to -12 mV. The encapsulation efficiency and loading capacity of Zn+2 were 0.6% and 8.5%, respectively. Cellular uptake studies showed a higher accumulation of PSMA-targeting liposome (TL) compared to non-targeting liposome (CL) in PSMA-expressing PC3 cells, whereas both liposomes showed low uptake in PSMA non-expressing cell. Furthermore, pre-treatment of PSMA-expressing cells with PSMA-specific peptide reduced the uptake of TL, indicating that the uptake of TL liposome is PSMA dependent. Finally, cytotoxicity studies showed that Zn-loaded TL, induces cell death in the PSMA-expressing cells. Overall, we developed PSMA-targeting Zn-containing liposomes that selectively target and kill PSMA-expressing prostate cancer cells. Future work includes testing the effect of Zn-loaded TL on m-aconitase activity and testing of in vivo efficacy of the formulation in prostate cancer models. Citation Format: Sujan K. Mondal, Alexander L. Klibanov, Anna Moore. Development of prostate specific membrane antigen-targeted liposomal zinc for the treatment of prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5750.

A self-cascade terpolymer platform for amplified chemo-chemodynamic therapy with synergistic immunogenic cell death enhancement

Chemodynamic therapy, which relies on the generation of cytotoxic radicals, can be amplified by a nanoplatform that produces hydroxyl radicals while also compromising natural radical scavenging mechanisms. For this purpose, a well-defined amphiphilic terpolymer, poly(oligo(ethylene glycol) monomethyl ether methacrylate)-block-poly(N,N-dimethyl aminoethyl methacrylate-statistical-monomer bearing ferrocene graft via azobenzene linker) (POEGMA-b-P(DMAEMA-st-(M-Azo-Fc), denoted as PAzo-Fc) is prepared by a consecutive reversible addition-fragmentation chain transfer (RAFT) polymerization technique, and is further used for doxorubicin (DOX) encapsulation to afford DOX-loaded stabilized nanomicelles, DOX@PAzo-Fc with an average hydrodynamic diameter of 86.0 nm. DOX@PAzo-Fc shows a self-cascade property for amplified CDT. That is, Azo cleavage-induced glutathione (GSH) depletion alleviates reactive oxygen species (ROS) scavenging. Together with the DOX-enhanced hydrogen peroxide generation, the Fc-mediated Fenton reaction is boosted for enhanced CDT. More importantly, the resulting amplified cascade chemo-chemodynamic therapy exerts a synergistic immunogenic cell death (ICD) enhancement effect for effective cancer immunotherapy, which further resulted in a high tumor inhibition rate of 87.8 % in murine tumor models. The uniqueness of this study is the construction of a minimalist nanoplatform based on M-Azo-Fc units for amplified CDT via simultaneously producing hydroxyl radicals and compromising natural radical scavenging mechanisms. Overall, this self-cascade terpolymer platform fabricated herein offers a facile yet robust approach for advanced combinatory cancer therapy with great potential for clinical translations.

Influence of the addition of carbon nanotube on the physical behavior of a lateritic soil from the southwest Amazon

In this work we evaluate the physical-mechanical behavior of lateritic soil with addition of carbon nanotubes. The soil was collected in a commercial deposit located in Rio Branco – AC and later characterized through particle size tests, X-Ray Diffraction, X-Ray Dispersion Spectroscopy and Tropical Compressed Miniature essay. The dispersion of nanotubes in solution was carried out and the size of the nanoparticles was verified using Dynamic Light Spreading - DLS, Zeta Potential and PDI. Three percentages of additions (0.05%, 0.1% and 0.2%) of carbon nanotubes were evaluated and compared with the control group according to the parameters of Atterberg limits, real density, dry density maximum and optimum humidity. The results indicate that the soil has a clayey behavior with a medium texture, with the presence of clay mineral kaolinite in its composition and silicon and iron oxides. The dispersion of carbon nanotubes reached particles with an average hydrodynamic diameter of 68.9 nm and Zeta Potential of -24.87 mV and PDI of 0.231, characterizing a solution as moderately dispersed and kinetically stable. The results of the liquidity limit and plasticity tests showed a reduction of 10 and 13%, respectively, with the addition of carbon nanotubes, while for the parameters of plasticity index, real specific mass, maximum dry density and optimal moisture, they did not show significant variation. Carbon nanotubes interact with soils with lateritic behavior, and further studies are essential to better understand the mechanisms behind this interaction.

Degradable Polymer-Based Nanoassemblies for Precise Targeting and Drug Delivery to Breast Cancer Cells without Affecting Normal Healthy Cells.

Stimuli-responsive amphiphilic polymers are known to be precursors to forming promising nanoarchitectonics with tunable properties for application in biomedical sciences. Currently, self-immolative polymers are widely recognized as an emerging class of responsive materials with excellent degradability, which is one of the crucial criteria for designing a robust drug delivery vehicle. Here, we design an amphiphilic polyurethane endowed with a redox-responsive self-immolative linker and a pH-responsive tertiary amine on the backbone, which forms entropy-driven nanoscale supramolecular assemblies (average hydrodynamic diameter ∼110 nm) and is programmed to disassemble in a redox environment (GSH) due to the degradation of the polymer in a self-immolative fashion. The nanoassembly shows efficient drug sequestration and release in a controlled manner in response to glutathione (10 mM). The tertiary amine residing on the surface of the nanoassembly becomes protonated in the tumor microenvironment (pH ∼ 6.4-6.8) and generates positively charged nanoassembly (ζ-potential = +36 mV), which enhances the cancer cell-selective cellular uptake. The biological evaluation of the drug-loaded nanoassembly revealed triple-negative breast cancer (MDAMB-231) selective internalization and cell death while shielding normal cells (RBCs or PBMCs) from off-targeting toxicity. We envision that polyurethane with a redox-responsive self-immolative linker might open up new opportunities for a completely degradable polyurethane-based nanocarrier for drug delivery and diagnosis applications.

The use of decorated titanium oxide nanoparticles for the development of handmade textile heritage in Egyptian villages: Design, mechanical, flammability, and antibacterial properties

AbstractImproving eco‐friendly coating‐based materials for wool artifacts, such as kilim fabric can inspire new‐fashion design avenues for conserving ancient cultural heritage. Thus, this research addresses an efficient treatment agent from natural rosin acids (R) and dapsone (D) with variable sublethal proportions of synthesized titanium dioxide nanoparticles (TiO2 NPs) (i.e., 0.1%, 0.3%, and 0.6%) for modifying kilim fabric (KF) using a dip‐coating method. The nanostructure of prepared TiO2 nanoparticles and their particle size were examined by x‐ray diffraction (XRD) and Zetasizer analyzer. The data showed that the majority of prepared TiO2 oriented to a rutile‐type structure with an average hydrodynamic diameter of 48.30–49.65 nm. The KF‐R/D‐0.3% TiO2 NPs specimen provided the best tensile properties reached ~3192 N compared with the untreated KF (i.e., 1125 N). This finding confirmed by SEM observations. Whereas, the specimen containing decorated TiO2 NPs (i.e., 0.6%) possessed higher flammability resistance property compared with other specimens. Moreover, XRD and FTIR results for treated KF specimens demonstrated the significant role of TiO2 NPs, which react with KF keratin either by new linkages or through chelating geometry to form a compact KF matrix. This contributed to enhance the tensile and flammability properties. Additionally, a great achievement in antibacterial properties occurred when TiO2 NPs used and their inhibitory zones were 18–36 mm, depending on the bacteria and specimen type.Highlights Novel treatment of KF fabric‐based bioagents with sublethal contents of TiO2 NPs was successfully prepared by dip‐coating route. The tensile force and flammability of treated KF fabric were greatly enhanced. A great achievement in antibacterial activity was noticed when TiO2 added. These treated fabrics have excellent possibility for use in conserving cultural heritage.

Development and performance evaluation of self-assembled pH-responsive curcumin-bacterial exopolysaccharide micellar conjugates as bioactive delivery system

The present study reports the synthesis of micellar conjugates, wherein curcumin (Cur), a bioactive compound with poor bioavailability, was covalently bonded to a bacterial exopolysaccharide (EPS). These conjugates were synthesized by utilizing succinic acid that linked Cur to the pyranosyl moiety of the EPS. The Cur-EPS conjugates appeared as spherical micelles in aqueous solution and were found to have an average hydrodynamic diameter of 254 ± 2.7 nm. The micellar conjugates showed superior stability than Cur as evident from their negative surface charge (−27 ± 1.8 mV) and low polydispersity index (PDI) (0.33 ± 0.04). The in vitro studies on release kinetics helped elucidate the pH-responsive characteristics of the Cur-EPS conjugate, as 87.50 ± 1.45 % of Cur was released at an acidic pH of 5.6, in contrast to 30.15 ± 2.61 % at systemic pH of 7.4 at 150 h. The conjugates were hemocompatible and exhibited cytotoxic effect against the osteosarcoma cell line (MG-63) after 48 h treatment. They also demonstrated superior antibacterial, antibiofilm, and antioxidant activities in comparison to free Cur. Therefore, the Cur-EPS conjugates have potential pharmaceutical applications as therapeutic biomaterial that can be applied as a drug delivery system.

The effects of high shear rates on the average hydrodynamic diameter measured in biomimetic HIV Gag virus-like particle dispersions.

HIV Gag virus-like particles (HIV Gag VLPs) are promising HIV vaccine candidates. In the literature, they are often described as shear-sensitive particles, and authors usually recommend the operation of tangential flow filtration (TFF) gently at shear rates below 4,000s-1 to 6,000s-1. This in turn poses a severe limitation to the performance of TFF-mediated concentration of VLPs, which would be substantially enhanced by working at higher shear rates. To our knowledge, studies examining the shear sensitivity of HIV Gag VLPs and providing detailed information and evidence for the fragility of these particles have not been conducted yet. Thus, we investigated the effect of high shear rates on the colloidal stability of mosaic VLPs (Mos-VLPs) as relevant examples for HIV Gag VLPs. For this purpose, Mos-VLPs were exposed to different shear rates ranging from 3,395s-1 to 22, 365s-1 for 2h. The average hydrodynamic diameter (AHD) and the polydispersity index (PDI) of the associated particle size distribution were used as stability indicators and measured after the treatment and during storage through dynamic light scattering. At high shear rates, we observed an increase in both AHD and PDI during the storage of HIV Mos1.Gag VLPs (bVLP-without envelope proteins) and Mos1.Gag + Mos2S.Env VLPs (eVLP-with envelope proteins). eVLPs exhibited higher colloidal stability than bVLPs, and we discuss the potential stabilizing role of envelope proteins. We finally demonstrated that the dispersion medium also has a considerable impact on the stability of Mos-VLPs.

Potentially Toxic Elements in Commercial Soap and Powder Detergent Samples

Dry decomposition, wet digestion, and dissolution in aqueous medium for direct analysis were evaluated for the preparation of eight samples of liquid and bar soap and one powder detergent for later determination of Cd, Mg, Pb, and Zn by inductively coupled plasma optical emission spectroscopy (ICP OES). The evaluation of the best conditions for digestion of the samples were chosen from a set of tests where conventional heating using 1 mol L-1 HNO3 with addition of 30% H2O2 proved to be the most efficient method. The average hydrodynamic diameter of 525 nm was determined using dynamic light scattering measurements. The concentrations found were: Cd and Pb (< limit of detection (LOD)), Mg (50.89 to 1119 μg g-1), and Zn (280.25 to 537.54 μg g-1). After evaluating the sample preparation methods, the accuracy of the methodology was verified through recovery tests of analytes, obtaining values between 83 and 119% and a relative standard deviation (RSD) ≤ 4.30% (n = 6; 4 mg L-1). The LOD ranged from 0.015 to 0.5 µg g-1 and the limits of quantification (LOQ) from 0.045 to 2 µg g-1. The soaps and powder detergent samples studied here may be used without any harm to health as the contents were within the limits established by the legislation.

Formulation Development and Characterization of Acitretin Proniosomal gel: In-vivo Exploration against Imiquimod-induced Psoriasis in Experimental Animals

he main purpose of this study was to prepare and evaluate acitretin proniosomal gel (APG) and find out if the antipsoriatic formulation could prevent Imiquimod (IMQ) induced psoriasis in experimental animals. APG was developed and by coacervation phase separation method. Cholesterol and soya lecithin was used as membrane modifiers and tween 80 and span 60 as non-ionic surfactants. Characterization of the prepared proniosomal gel revealed that the optimized batch APG3 presented excellent formulation characteristics like the viscosity of 9710 ± 1.24 cps, rate of spontaneity as 13 ± 0.86, %entrapment efficiency of 94.91 ± 0.51, average hydrodynamic diameter of niosomes as 345.7 nm, polydispersibility index as 0.159 and ZP of -2.3 mV. In-vivo animal study of the optimized batch APG3 was performed along with biochemical estimations of oxidative parameters as glutathione (GSH), superoxide dismutase (SOD), malondialdehyde (MDA) and catalase; also, TNF-α, IL-6 were estimated using ELISA sandwiched. Histopathological estimation along with psoriasis area severity index (PASI) scores in the IMQ-induced psoriatic model presented a significant fall in the scoring after treatment with APG3 compared with a psoriatic group. Primary dermal irritation scoring was also evaluated on Sprague Dawley rats. The results presented a considerable decline in skin irritation score compared with a psoriatic group. Also, the levels of GSH, SOD and catalase were increased in APG3 treated group as compared with a psoriatic group. While MDA level is decreased after topical treatment with APG3 compared with a psoriatic group. In conclusion, the optimized APG3 showed promising pharmacological effects in the treatment of psoriasis.

Design and Characterization of Calcipotriol Proniosomal Gel: In-vivo Exploration against Imiquimod-induced Psoriasis in Experimental Animals

The present work focuses on the preparation and evaluation of calcipotriol proniosomal gel (CPG) and find out if the antipsoriatic formulation could prevent imiquimod (IMQ) induced psoriasis in experimental animals. CPG was designed and developed by the coacervation phase separation method. Cholesterol and soya lecithin was used as membrane modifiers and tween 80 and span 60 as non-ionic surfactants. The developed proniosomal gels were characterized which revealed that the optimized batch CPG3 presented excellent formulation characteristics like viscosity of 9690 ± 1.43 cps, rate of spontaneity as 14 ± 1.37, %entrapment efficiency of 82.71 ± 0.48, the average hydrodynamic diameter of niosomes as 739.1 nm, polydispersibility index as 0.360 and ZP of -2.8 mV. In-vivo animal study of the optimized batch CPG3 was performed along with biochemical estimations of oxidative parameters such as glutathione (GSH), superoxide dismutase (SOD), malondialdehyde (MDA) and catalase; also, tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) were estimated using enzyme-linked immunoassay (ELISA) sandwiched. Histopathological estimation along with psoriasis area severity index (PASI) scores in the IMQ-induced psoriatic model revealed a significant decline in the scoring after treatment with CPG3 compared with a psoriatic group. Primary dermal irritation scoring was also evaluated on Sprague Dawley rats. The results revealed a considerable decrease in skin irritation score compared with a psoriatic group. Also, the levels of GSH, SOD and catalase were raised in CPG3 treated group as compared with a psoriatic group. While MDA level was declined after topical treatment with CPG3 compared with a psoriatic group. In conclusion, the optimized CPG3 showed promising pharmacological effects in the treatment of psoriasis

Remediation of arsenic-contaminated soil using nanoscale schwertmannite synthesized by persulfate oxidation with carboxymethyl cellulose stabilization

Schwertmannite (SCH) is a promising material for adsorbing inorganic arsenic (As). We synthesized SCH nanoparticles (nano-SCH) via a modified chemical oxidation method and investigated the application of nano-SCH for the remediation of As-contaminated soils. The production of nano-SCH was successfully prepared using the persulfate oxidation method with carboxymethyl cellulose stabilization. The spherical structure of the nano-SCH particles had an average hydrodynamic diameter of 296 nm with high specific surface areas (108.9 m2/g). Compared with SCH synthesized via the H2O2 oxidation method, the percentage of Fe3+ precipitation in nano-SCH synthesis increased from 63.2% to 84.1%. The inorganic As adsorption capacity of nano-SCH improved by 2.27 times at solution pH = 6. After remediation of heavily As-contaminated soils by using 5% nano-SCH, the leachability of inorganic As rapidly decreased to 0.01% in 30 d. Correspondingly, the immobilization efficiencies of inorganic As in soil reached >99.9%. The inorganic As fractions in treated soil shifted from specifically and nonspecifically bound forms to amorphous and crystalline hydrous oxide-bound fractions. After treatment with 5% nano-SCH for 60 d, soil pH slightly decreased from 5.47 to 4.94; by contrast, soil organic matter content increased by 20.9%. Simultaneously, dehydrogenase concentration in soil decreased by 22.4%–34.7% during the remediation process. These changes in soil properties and As immobilization jointly decreased microbial activity and initiated the re-establishment of bacterial communities in the soil. In summary, this study presents a novel and high-productivity technology for nano-SCH synthesis and confirms the high As immobilization effectiveness of nano-SCH in the remediation of As-contaminated soils.

Effect of maltodextrin and inulin addition on the dairy-based powders properties

Dairy-based powders produced from the combination of concentrated milk, whey, and maltodextrin (main constituents) were used as ingredients during infant formula production. The relation between the composition of each treatment and physicochemical properties of the powders were evaluated. In work, dairy-based powders were obtained by a mixture of concentrated milk and whey. Increasing the ratio whey/milk in the mixture before drying increases the concentration of lactose into dairy based powders and reduces total protein and fat content. Besides, the addition of maltodextrin and inulin reduced powder agglomeration increased the average hydrodynamic diameter of the particles, and the theoretical glass transition temperature, exhibited strong spectral contributions to Raman spectroscopy. It was possible to infer changes in the bands by Raman spectroscopy between the formulated products, the main changes were related to the presence of lactose, maltodextrin, and inulin. Inulin is a better option than maltodextrin for drying dairy-based powders mainly because of its nutritional benefits.

Efficient and Traceable Tamoxifen Delivery to Breast Cancer Cells Using Folic Acid‐Decorated and PEGylated Graphene Quantum Dots

AbstractGraphene quantum dots (GQDs) possess potential properties for the targeted transport and tracking of anticancer medication to tumor cells. For this purpose, the synthesized GQDs were decorated with folic acid (FA) and methoxy polyethylene glycol (mPEG2000), and finally loaded with tamoxifen (TMX) drug. The synthesized nano‐drug was characterized using FTIR, XRD, UV‐Vis, PL, HRTEM, FESEM, and DLS analytical devices. Based on the obtained data, the average hydrodynamic diameter of particles dissolved in water was 294.7 nm and the size of dehydrated particles was between 53 and 210 nm. PL data showed that prepared nanoparticles have an emission wavelength of 438 nm, which is in the blue fluorescent wavelength range, thus making these nanoparticles suitable for cell imaging. The encapsulation efficiency and loading percentage of tamoxifen in nanoparticles were calculated at about 52.5 % and 30 %, respectively, and cumulative drug release reached 89 % within 42 hours. The cytotoxicity effects of nanoparticles were investigated. According to IC50 results, the targeted mPEG‐GQDs‐FA/TMX (TMX‐FPGs) nano‐drug was more toxic than free TMX on MCF‐7 cells and had reduced side effects on healthy HDF cells. TMX‐FPGs induced apoptosis cell death, significantly. The confocal imaging experiments showed that TMX‐FPGs are appropriate for monitoring and targeting MCF‐7 cells.

Production of highly antioxidant lignin nanoparticles from a hardwood technical lignin

Eucalypt kraft lignin isolated in a LignoBoost™ pilot plant was characterized by GC–MS, ICP-OES, DSC, HPSEC, 31P NMR, and HSQC 2D-NMR to be used without any further processing to produce lignin nanoparticles (LNPs) by nanoprecipitation. Tetrahydrofuran (THF) was used as a solvent, and water as a non-solvent. Microscopic analysis (TEM) showed that LNPs were regularly spherical with some hollow particles dispersed in-between, and sizes were tunable by changing the solvent dripping rate onto the non-solvent. LNP particle sizes had a bimodal distribution, with the largest population having an average apparent hydrodynamic diameter ranging from 105.6 to 75.6 nm. Colloidal dispersions of LNPs in water presented good stability in different dilutions without significant size changes upon storage at pH close to neutral for as long as 45 days. Zeta potentials around −40 mV were obtained for LNP suspensions at pH ranging from 7 to 9. The high carbohydrate content (circa 10 % on a dry basis, mostly xylans) of the lignin precursor did not interfere in LNP formation, whose antioxidant activity was expressive as demonstrated by the ABTS assay at pH 7.4, with an EC50 of 4.04 μg mL−1. Also, the Trolox® equivalent antioxidant capacity (TEAC) of LNPs reached 1.90 after 40 min reaction time.

Towards nanomaterials with tubular pores: synthesis and self-assembly of bis-pillar[5]arene

Recently, materials obtained using supramolecular chemistry approaches, and, in particular, spatially preorganized macrocyclic compounds, have attracted close attention of the researchers. Pillar[n]arenes are of special interest due to their tubular spatial structure and macrocyclic cavity. A similar tubular structure is retained in the supramolecular packaging of pillar[5]arene crystals, forming pores. In this study, we developed a block synthetic approach for the preparation of bis-pillar[5]arene containing amide groups. The ability of the synthesized bis-pillar[5]arene to form stable self-associates in solvents of different polarity (CHCl3 and CH3OH) was demonstrated by the DLS method. In trichloromethane at concentration of 1·10–3 M, monodisperse associates with average hydrodynamic diameter of 227 nm (PDI = 0.28) are formed; in methanol, stable associates (1·10–6 M) have an average hydrodynamic diameter of 136 nm (PDI = 0.21). The results obtained can be used to create new supramolecular systems, molecular machines, or capture and detect various organic molecules.

Supported Erythrocyte Membranes on Piezoelectric Sensors for Studying the Interactions with Nanoparticles.

Applications of nanoparticles (NPs) in nanodrugs, food additives, and cosmetics can result in the presence of nanomaterials in the human circulatory system and their attachment to red blood cells (RBCs), which may lead to cytotoxic effects. To investigate the interactions of NPs with RBC membranes (RBCm), supported erythrocyte membranes (SRBCm) were developed on piezoelectric sensors in a quartz crystal microbalance with dissipation (QCM-D) at 25 °C. A well-dispersed RBCm suspension at 1 mM NaCl and 0.2 mM NaHCO3 was obtained from whole blood and comprised colloidal membrane fragments with the average hydrodynamic diameter and zeta potential of 390 nm and -0.53 mV, respectively, at pH 7.0. The thin and rigid SRBCm was formed mainly through the deposition of RBCm fragments on the poly-l-lysine-modified crystal sensor, leading to the average frequency shift of -26.2 Hz and the low ratio of the dissipation to frequency shift (7.2 × 10-8 Hz-1). The complete coverage of SRBCm was indicated by the plateau of the frequency shift in the stage of SRBCm formation and no deposition of negatively charged 106 nm polystyrene nanoparticles (PSNPs) on the SRBCm. Atomic force microscopy and immunofluorescence microscopy images showed that RBCm aggregates with the average size of 420 nm and erythrocyte membrane proteins existed on SRBCm, respectively. The methods of determining attachment efficiencies of model positively charged NPs (i.e., hematite NPs or HemNPs) and model negatively charged NPs (i.e., PSNPs) on SRBCm were demonstrated in 1 mM NaCl solution at pH 5.1 and pH 7.0, respectively. HemNPs exhibited a favorable deposition with an attachment efficiency of 0.99 while PSNPs did not show any attachment propensity toward SRBCm.

Wound healing and antidiabetic properties of green synthesized silver nanoparticles in 3T3-L1 mouse embryo fibroblast cells through 2-NBDG expression

The antibacterial and antifungal properties of silver and silver-based compounds have been recognized for quite some time. This study employed an extracellular method to produce silver nanoparticles (AgNPs) using the leaves of Barringtonia racemosa (B. racemosa). B. racemosa's aqueous leaf extract underwent a color change from grey to dark brown, which revealed the formation of AgNPs. UV spectrophotometry analysis confirmed the presence of silver with the maximum absorbance of 427 nm. FTIR analysis supported the existence of alcohols with the OH stretch and alkenes with the CC stretch. The existence of AgNPs with an average hydrodynamic diameter of 36.58 nm was confirmed using dynamic light scattering (DLS). Energy dispersive X-ray spectroscopy (EDX) confirmed the presence of silver. Additionally, the AgNPs showed spherical structure particles with the size distribution ranging from 10 to 17 nm with polydispersity, under transmission electron microscopy (TEM). Thermogravimetric analysis (TGA) findings revealed that AgNPs maintain good thermal stability even at high temperatures. A variety of bacterial and fungal pathogens were successfully inhibited by the AgNPs, with S. epidermidis (27 mm) showing the strongest antibacterial activity and a 20 mm inhibitory zone was against Candida albicans for its antifungal activity. Furthermore, AgNPs also showed a positive synergistic impact with the tested antibiotic and antifungal agents. In addition, the AgNPs demonstrated strong antioxidant activity. The considerable inhibition of alpha amylase and alpha glucosidase by the AgNPs were noted by their respective IC50 values of 16.65 μg/ml and 18.97 μg/ml. Flow cytometry analysis revealed a significant increase in glucose uptake by 3T3-L1 cells after exposure to AgNPs, as indicated by the upregulation of 2-(N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl) amino)-2-deoxyglucose (2-NBDG) expression. In 3T3/L cells, the AgNPs also demonstrated remarkable potential in accelerating wound healing achieving 92% closure of wounds after 48 h of incubation. As a result, it can be concluded that the AgNPs exhibit positive antidiabetic properties, suggesting their potential applications in the pharmaceutical industry including in the management of diabetic foot ulcers.