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1.
Lasers Med Sci ; 39(1): 45, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38253944

RESUMO

Chlorophyll (Chl) is a promising natural photosensitizer (PS) in photodynamic treatment (PDT). Mesoporous silica nanoparticles (MSNs) were chosen to increase the effectiveness of PDT. This study aimed to evaluate the synergistic efficacy of chlorophyll-loaded mesoporous silica nanoparticles (Chl-MSNs) with photodynamic therapy (PDT) and to investigate their potential toxicity in HepG2, MDA-MB-231, and HSF cell lines. Chl-MSNs were prepared via the physical adsorption method. TEM, DLS, and zeta potential examined morphology, size, and surface characteristics. MSNs and Chl-MSNs were characterized using the same techniques. HPLC was used to assess the encapsulation efficiency. At pH 7.4, an in vitro release experiment of Chl-MSNs was performed. Chl, MSNs, and Chl-MSNs were applied to the three cell lines at different concentrations and subjected to red (650 nm) and blue (450-500 nm) lasers. MSNs and Chl-MSNs' sizes were 90.338 ± 38.49 nm and 123.84 ± 15.67 nm, respectively, as obtained by TEM; the hydrodynamic diameter for MSNs (93.69 ± 20.53 nm) and Chl-MSNs (212.95 ± 19.76 nm); and their zeta potential values are - 16.7 ± 2.19 mV and - 18.84 ± 1.40 mV. The encapsulation efficiency of Chl-MSNs was 70%. Chl-MSNs displayed no toxicity in dark conditions but showed excellent photostability under blue and red light exposure. Furthermore, using Chl over Chl-MSNs has a higher PDT efficiency than the tested cell lines. Chl-MSNs have the potential to be an effective delivery system. PDT proved to be an essential technique for cancer treatment. Blue laser is recommended over red laser with Chl and MSNs for destroying cancer cells.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Linhagem Celular , Clorofila/farmacologia , Neoplasias/tratamento farmacológico , Dióxido de Silício
3.
Sci Rep ; 13(1): 19730, 2023 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-37957193

RESUMO

Microalgae have the potential to become the primary source of biodiesel, catering to a wide range of essential applications such as transportation. This would allow for a significant reduction in dependence on conventional petroleum diesel. This study investigates the effect of biostimulation techniques utilizing nanoparticles of Magnesium oxide MgO, Calcium hydroxyapatite Ca10(PO4)6(OH)2, and Zinc oxide ZnO to enhance the biodiesel production of Chlorella sorokiniana. By enhancing cell activity, these nanoparticles have demonstrated the ability to improve oil production and subsequently increase biodiesel production. Experimentally, each nanomaterial was introduced at a concentration of 15 mg L-1. The results have shown that MgO nanoparticles yielded the highest biodiesel production, with a recorded yield of 61.5 mg L-1. Hydroxyapatite nanoparticles, on the other hand, facilitated lipid accumulation. ZnO nanoparticles showcased a multifaceted advantage by enhancing both growth and lipid content. Thus, it is suggested that these nanoparticles can be used effectively to increase the lipid content of microalgae. These findings highlight the potential of biostimulation strategies utilizing MgO, hydroxyapatite, and zinc oxide nanoparticles to bolster biodiesel production.


Assuntos
Chlorella , Microalgas , Nanopartículas , Óxido de Zinco , Biocombustíveis , Óxido de Magnésio , Biomassa , Lipídeos , Hidroxiapatitas
4.
Sci Rep ; 13(1): 2720, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36792676

RESUMO

Environmental issues are brought up concerning the production of Portland cement. As a result, biocement serves as a reliable substitute for Portland cement in green construction projects. This study created a brand-new technique to create high-quality biocement from agricultural wastes. The technique is based on nanomaterials that improve and accelerate the "Microbially Induced Calcite Precipitation (MICP)" process, which improves the quality of the biocement produced. The mixture was further mixed with the addition of 5 mg/l of graphitic carbon nitride nanosheets (g-C3N4 NSs), alumina nanoparticles (Al2O3 NPs), or silica nanoparticles (SiO2 NPs). The cement: sand ratio was 1:3, the ash: cement ratio was 1:9, and water: cement ratio was 1:2. Cubes molds were prepared, and then cast and compacted. Subsequent de-molding, all specimens were cured in nutrient broth-urea (NBU) media until testing at 28 days. The medium was replenished at an interval of 7 days. The results show that the addition of 5 mg/l of g-C3N4 NSs with corncob ash delivered the highest "Compressive Strength" and the highest "Flexural Strength" of biocement mortar cubes of 18 and 7.6 megapascal (MPa), respectively; and an acceptable "Water Absorption" (5.42%) compared to all other treatments. This treatment delivered a "Compressive Strength", "Flexural Strength", and "Water Absorption" reduction of 1.67, 1.26, and 1.21 times the control (standard Portland cement). It was concluded that adding 5 mg/l of g-C3N4 NSs to the cementitious mixture enhances its properties, where the resulting biocement is a promising substitute for conventional Portland cement. Adding nanomaterials to cement reduces its permeability to ions, increasing its strength and durability. The use of these nanomaterials can enhance the performance of concrete infrastructures. The use of nanoparticles is an effective solution to reduce the environmental impact associated with concrete production.

5.
Environ Sci Pollut Res Int ; 27(28): 35828-35836, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32601878

RESUMO

In this work, titanium dioxide nanoparticles (TiO2 NPs) and modified TiO2 NPs with silver (Ag) or platinum (Pt) dopant were developed through photodeposition method for the NOx conversion into nitric acid (HNO3) under visible light irradiation. The formed photocatalysts TiO2, Ag/TiO2, and Pt/TiO2 nanocomposites were characterized by utilizing TEM, SEM, energy-dispersive X-ray analysis (EDX), XRD, UV/visible diffuse reflectance spectroscopy (UV-Vis DRS), and FT-IR. It had been investigated that an enhancement within the conversion of NOx into HNO3 was increased from 34.3 to 78.3% for Ag/TiO2 and from 35.2 to 78.5% for Pt/TiO2 under visible light irradiation conditions at room temperature for less than 2 h. The photodegradation rate order of NOx under visible light irradiation is Pt/TiO2 ~ Ag/TiO2 > TiO2. A possible mechanism for the catalytic conversion of NOx gases has been proposed, which depends on the photogeneration of electrons and holes after the excitation of nanocatalysts under visible radiation that promoted superoxide and hydroxyl ions, which can depredate NOx gases. This approach of NOx photocatalytic conversion is characterized by its chemical stability, low cost, high efficiency, simple operation, and strong durability than traditional methods.


Assuntos
Nanopartículas , Platina , Catálise , Luz , Óxidos de Nitrogênio , Prata , Espectroscopia de Infravermelho com Transformada de Fourier , Titânio
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