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1.
J Environ Manage ; 365: 121603, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38963967

RESUMO

Water treatment has turned out to be more important in most societies due to the expansion of most economies and to advancement of industrialization. Developing efficient materials and technologies for water treatment is of high interest. Thin film nanocomposite membranes are regarded as the most effective membranes available for salts, hydrocarbon, and environmental pollutants removal. These membranes improve productivity while using less energy than conventional asymmetric membranes. Here, the polyvinylidene fluoride (PVDF) membranes have been successfully modified via dip single-step coating by silica-aminopropyl triethoxysilane/trimesic acid/melamine nanocomposite (Si-APTES-TA-MM). The developed membranes were evaluated for separating the emulsified oil/water mixture, the surface wettability of the membrane materials is therefore essential. During the conditioning step, that is when the freshwater was introduced, the prepared membrane reached a flux of about 27.77 L m-2 h-1. However, when the contaminated water was introduced, the flux reached 18 L m-2 h-1, alongside an applied pressure of 400 kPa. Interestingly, during the first 8 h of the filtration test, the membrane showed 90 % rejection for ions including Mg2+, and SO42- and ≈100 % for organic pollutants including pentane, isooctane, toluene, and hexadecane. Also, the membrane showed 98 % rejection for heavy metals including strontium, lead, and cobalt ions. As per the results, the membrane could be recommended as a promising candidate to be used for a mixture of salt ions, hydrocarbons, and mixtures of heavy metals from wastewater.


Assuntos
Membranas Artificiais , Silanos , Poluentes Químicos da Água , Purificação da Água , Purificação da Água/métodos , Silanos/química , Poluentes Químicos da Água/química , Metais/química , Óleos/química , Propilaminas/química , Sais/química , Interações Hidrofóbicas e Hidrofílicas , Íons , Polivinil/química
2.
Int J Biol Macromol ; 277(Pt 2): 134185, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39074694

RESUMO

Critical-size bone defect repair presents multiple challenges, such as osteogenesis, vascularization, and neurogenesis. Current biomaterials for bone repair need more consideration for the above functions. Organic-inorganic composites combined with bioactive ions offer significant advantages in bone regeneration. In our work, we prepared an organic-inorganic composite material by blending polylactic acid (PLA) with 3-aminopropyltriethoxysilane (APTES)-modified magnesium silicate (A-M2S) and fabricated it by 3D printing. With the increase of A-M2S proportion, the hydrophilicity and mineralization ability showed an enhanced trend, and the compressive strength and elastic modulus were increased from 15.29 MPa and 94.61 MPa to 44.30 MPa and 435.77 MPa, respectively. Furthermore, A-M2S/PLA scaffolds not only exhibited good cytocompatibility of bone marrow mesenchymal stem cells (BMSCs), human umbilical vein endothelial cells (HUVECs), and Schwann cells (SCs), but also effectively promoted osteogenesis, angiogenesis, and neurogenesis in vitro. After implanting 10% A-M2S/PLA scaffolds in vivo, the scaffolds showed the most effective repair of cranium defects compared to the blank and control group (PLA). Additionally, they promoted the secretion of proteins related to bone regeneration and neurovascular formation. These results provided the basis for expanding the application of A-M2S and PLA in bone tissue engineering and presented a novel concept for neurovascularized bone repair.


Assuntos
Regeneração Óssea , Células Endoteliais da Veia Umbilical Humana , Silicatos de Magnésio , Células-Tronco Mesenquimais , Osteogênese , Poliésteres , Impressão Tridimensional , Alicerces Teciduais , Regeneração Óssea/efeitos dos fármacos , Alicerces Teciduais/química , Poliésteres/química , Humanos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Osteogênese/efeitos dos fármacos , Animais , Silicatos de Magnésio/química , Engenharia Tecidual/métodos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Células de Schwann/efeitos dos fármacos , Células de Schwann/citologia , Silanos/química , Silanos/farmacologia , Neurogênese/efeitos dos fármacos , Propilaminas/química , Propilaminas/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos
3.
Int J Pharm ; 662: 124487, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39029634

RESUMO

In the current study, a tumor microenvironment responsive (TME-responsive) copper peroxide-mesoporous silica core-shell structure with H2O2 self-supplying ability was fabricated for targeted ferroptosis/chemotherapy against metastatic breast cancer. At the first stage, copper peroxide nanodot was synthesized and subsequently coated with mesoporous organosilica shell. After (3-Aminopropyl) triethoxysilane (APTMS) functionalization of the organosilica shell, doxorubicin (DOX) was loaded in the mesoporous structure of the nanoparticles and then, heterofunctional COOH-PEG-Maleimide was decorated on the surface through EDC/NHS chemistry. Afterward, thiol-functionalized AS1411 aptamer was conjugated to the maleimide groups of the PEGylated nanoparticles. In vitro study illustrated ROS generation of the system in the treated 4 T1 cell. Cellular uptake and cytotoxicity experiments showed enhanced internalization and cytotoxicity of the targeted system comparing to non-targeted one. The in vivo study on ectopic 4 T1 tumor induced in Female BALB/c mice showed ideal therapeutic effect of Apt-PEG-Silica-DOT@DOX with approximately 90 % tumor suppression in comparison with 50 % and 25 % tumor suppression for PEG-Silica-DOT@DOX and PEG-Silica-DOT. Moreover, Apt-PEG-Silica-DOT@DOX provide favorable characteristics for biosafety issues concerning the rate of survival and loss of body weight. The prepared platform could serve as a multifunctional system with smart behavior in drug release, tumor accumulation and capable for ferroptosis/chemotherapy against breast cancer.


Assuntos
Neoplasias da Mama , Doxorrubicina , Ferroptose , Camundongos Endogâmicos BALB C , Nanopartículas , Dióxido de Silício , Animais , Feminino , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacologia , Ferroptose/efeitos dos fármacos , Dióxido de Silício/química , Dióxido de Silício/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Nanopartículas/administração & dosagem , Nanopartículas/química , Linhagem Celular Tumoral , Camundongos , Polietilenoglicóis/química , Polietilenoglicóis/administração & dosagem , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/farmacocinética , Humanos , Porosidade , Peróxidos/química , Peróxidos/administração & dosagem , Silanos/química , Silanos/administração & dosagem , Portadores de Fármacos/química , Microambiente Tumoral/efeitos dos fármacos , Cobre/química , Cobre/administração & dosagem , Propilaminas/química , Propilaminas/administração & dosagem
4.
Int J Pharm ; 661: 124389, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38942185

RESUMO

We have recently witnessed that considerable progresses have been made in the rapid detection and appropriate treatments of COVID-19, but still this virus remains one of the main targets of world research. Based on the knowledge of the complex mechanism of viral infection we designed peptide-dendrimer inhibitors of SARS-CoV-2with the aim to block cell infection through interfering with the host-pathogen interactions. We used two different strategies: i) the first one aims at hindering the virus anchorage to the human cell; ii) the second -strategy points to interfere with the mechanism of virus-cell membrane fusion. We propose the use of different nanosized carriers, formed by several carbosilane dendritic wedges to deliver two different peptides designed to inhibit host interaction or virus entry. The antiviral activity of the peptide-dendrimers, as well as of free peptides and free dendrimers was evaluated through the use of SARS-CoV-2 pseudotyped lentivirus. The results obtained show that peptides designed to block host-pathogen interaction represent a valuable strategy for viral inhibition.


Assuntos
Antivirais , Tratamento Farmacológico da COVID-19 , Dendrímeros , Peptídeos , SARS-CoV-2 , Dendrímeros/química , Dendrímeros/farmacologia , Humanos , SARS-CoV-2/efeitos dos fármacos , Antivirais/farmacologia , Antivirais/química , Peptídeos/química , Peptídeos/farmacologia , Internalização do Vírus/efeitos dos fármacos , Desenho de Fármacos , COVID-19/virologia , Silanos/química , Silanos/farmacologia , Interações Hospedeiro-Patógeno
5.
Int J Biol Macromol ; 273(Pt 1): 132832, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38834123

RESUMO

The fragility of the skeleton and poor bioaccessibility limit Silica aerogel's application in the food industry. In this study, composite gels were obtained by cross-linking pea proteins isolate (PPI) with Tetraethoxysilane (TEOS)to improve the bioavailability of silica-derived aerogels. It indicated that TEOS first condensed with H+ to form secondary particles and then complexed with PPI via hydroxyl groups to form a composite aerogel. Meanwhile, the PPI-Si composite aerogel formed a dense mesoporous structure with a specific surface area of 312.5 g/cm3. This resulted in a higher oil holding percentage of 89.67 % for the PPI (10 %)-Si aerogel, which was 34.1 % higher than other studies, leading to a more stable oleogel. Finally, as a delivery system, the composite oleogel not only could significantly increase the bioaccessibility rate by 27.4 % compared with silica aerogel, but also could efficiently inhibit the premature release of curcumin in the simulated gastric fluids, while allowed sustainably release in the simulated intestinal fluids. These results provided a theoretical basis for the application of silica-derived aerogels in food and non-food applications.


Assuntos
Curcumina , Proteínas de Ervilha , Dióxido de Silício , Curcumina/química , Curcumina/farmacologia , Dióxido de Silício/química , Proteínas de Ervilha/química , Géis/química , Portadores de Fármacos/química , Silanos/química , Disponibilidade Biológica , Porosidade , Sistemas de Liberação de Medicamentos , Compostos Orgânicos
6.
Toxicol In Vitro ; 99: 105850, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38801838

RESUMO

Cytotoxic and genotoxic effects of novel mPEG-silane coated iron(III) oxide nanoparticles doped with magnesium (Mg0.1-γ-Fe2O3(mPEG-silane)0.5) have been investigated on human adenocarcinomic alveolar basal epithelial (A549) and human normal bronchial epithelial (BEAS-2B) cells. In the studies several molecular and cellular targets addressing to cell membrane, cytoplasm organelles and nucleus components were served as toxicological endpoints. The as-synthesized nanoparticles were found to be stable in the cell culture media and were examined for different concentration and exposure times. No cytotoxicity of the tested nanoparticles was found although these nanoparticles slightly increased reactive oxygen species in both cell types studied. Mg0.1-γ-Fe2O3(mPEG-silane)0.5 nanoparticles did not produce any DNA strand breaks and oxidative DNA damages in A549 and BEAS-2B cells. Different concentration of Mg0.1-γ-Fe2O3(mPEG-silane)0.5 nanoparticles and different incubation time did not affect cell migration. The lung cancer cells' uptake of the nanoparticles was more effective than in normal lung cells. Altogether, the results evidence that mPEG-silane coated iron(III) oxide nanoparticles doped with magnesium do not elucidate any deleterious effects on human normal and cancerous lung cells despite cellular uptake of these nanoparticles. Therefore, it seems reasonable to conclude that these novel biocompatible nanoparticles are promising candidates for further development towards medical applications.


Assuntos
Dano ao DNA , Pulmão , Magnésio , Polietilenoglicóis , Silanos , Humanos , Silanos/toxicidade , Silanos/química , Polietilenoglicóis/toxicidade , Polietilenoglicóis/química , Magnésio/química , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/citologia , Neoplasias Pulmonares/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Linhagem Celular , Compostos Férricos/toxicidade , Compostos Férricos/química , Movimento Celular/efeitos dos fármacos , Nanopartículas Magnéticas de Óxido de Ferro/toxicidade , Nanopartículas Magnéticas de Óxido de Ferro/química , Linhagem Celular Tumoral , Células A549
7.
Analyst ; 149(13): 3615-3624, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38775016

RESUMO

Mycophenolate mofetil (MpM) is a medication used to prevent the rejection of transplanted organs, particularly in kidney, heart, and liver transplant surgeries. It is extremely important to be conscious that MpM can raise the risk of severe infections and some cancers if it exceeds the recommended dose while lower doses will result in organ rejections. So, it is essential to monitor the dosage of MpM in real time in the micromolar range. In this work, we have synthesized 3-aminopropyltriethoxysilane (APTES) functionalized nickel cobaltite (NiCo2O4) and this amino functionalization was chosen to enhance the stability and electrochemical activity of NiCo2O4. The enhanced activity of NiCo2O4 was used for developing an electrochemical sensor for the detection of MpM. APTES functionalized NiCo2O4 was coated on carbon cloth and used as the working electrode. Surface functionalization with APTES on NiCo2O4 was aimed at augmenting the adsorption/interaction of MpM due to its binding properties. The developed sensor showed a very low detection limit of 1.23 nM with linear ranges of 10-100 nM and 1-100 µM and its practical applicability was examined using artificial samples of blood serum and cerebrospinal fluid, validating its potential application in real-life scenarios.


Assuntos
Carbono , Imunossupressores , Limite de Detecção , Ácido Micofenólico , Nanoestruturas , Níquel , Ouriços-do-Mar , Dispositivos Eletrônicos Vestíveis , Animais , Níquel/química , Ácido Micofenólico/sangue , Ácido Micofenólico/química , Ácido Micofenólico/análise , Imunossupressores/sangue , Imunossupressores/análise , Imunossupressores/química , Carbono/química , Ouriços-do-Mar/química , Nanoestruturas/química , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/instrumentação , Propilaminas/química , Humanos , Cobalto/química , Eletrodos , Silanos
8.
Int J Pharm ; 658: 124199, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38703928

RESUMO

Dendrimers have emerged as an important group of nanoparticles to transport drugs, DNA, or RNA into target cells in cancer and other diseases. Various functional modifications can be imposed on dendrimers to increase the efficacy and specificity in delivering their cargo to the target cells and decrease their toxicity. In the present work, we evaluated the potential of carbosilane polyphenolic dendrimers modified with caffeic acid (CA) and polyethylene glycol (PEG) to deliver proapoptotic Mcl-1 and Bcl-2 siRNAs to A549 cancer cells. Dendrimers formed stable complexes with siRNAs as assessed by transmission electron microscopy and gel electrophoresis. Modification of dendrimers with PEG reduced the size and the zeta potential of dendrimer/siRNA complexes. The presence of PEG caused a red shift of the CD spectrum, and this effect was the more pronounced, the higher the dendrimer/siRNA ratio was. The nanocomplexes were internalized by A549. All studied dendrimer/siRNA formulations inhibited tumor cell migration and adhesion and caused an increase in the population of early apoptotic cells. Among four tested dendrimers, the polyphenolic compound containing two caffeic acid moieties complexed with siRNA demonstrated the lowest polydispersity index and showed an excellent transfection profile. In conclusion, this dendrimer are a promising candidate for the delivery of siRNA into cancer cells in further in vivo studies.


Assuntos
Apoptose , Dendrímeros , Polietilenoglicóis , Polifenóis , RNA Interferente Pequeno , Humanos , Dendrímeros/química , Dendrímeros/administração & dosagem , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/química , Células A549 , Apoptose/efeitos dos fármacos , Polifenóis/química , Polifenóis/farmacologia , Polifenóis/administração & dosagem , Polietilenoglicóis/química , Proteínas Proto-Oncogênicas c-bcl-2/genética , Ácidos Cafeicos/química , Ácidos Cafeicos/farmacologia , Ácidos Cafeicos/administração & dosagem , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Movimento Celular/efeitos dos fármacos , Portadores de Fármacos/química , Silanos/química , Transfecção/métodos , Linhagem Celular Tumoral
9.
Int J Biol Macromol ; 269(Pt 2): 132266, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38777689

RESUMO

Bacterial cellulose (BC) represents a promising biomaterial, due to its unique and versatile properties. We report, herein, on purposely-designed structural modifications of BC that enhance its application as a wound dressing material. Chemical modification of the functional groups of BC was performed initially to introduce a hydrophobic/oleophilic character to its surface. Specifically, silanization was carried out in an aqueous medium using methyltrimethoxisilane (MTMS) as the silanizing agent, and aerogels were subsequently prepared by freeze-drying. The BC-MTMS aerogel obtained displayed a highly porous (99 %) and lightweight structure with an oil absorption capacity of up to 52 times its dry weight. The XRD pattern indicated that the characteristic crystallographic planes of the native BC were maintained after the silanization process. Thermal analysis showed that the thermal stability of the BC-MTMS aerogel increased, as compared to the pure BC aerogel (pBC). Moreover, the BC-MTMS aerogel was not cytotoxic to fibroblasts and keratinocytes. In the second step of the study, the incorporation of natural oils into the aerogel's matrix was found to endow antimicrobial and/or healing properties to BC-MTMS. Bourbon geranium (Pelargonium X ssp.) essential oil (GEO) was the only oil that exhibited antimicrobial activity against the tested microorganisms, whereas buriti (Mauritia flexuosa) vegetable oil (BVO) was non-cytotoxic to the cells. This study demonstrates that the characteristics of the BC structure can be modified, while preserving its intrinsic features, offering new possibilities for the development of BC-derived materials for specific applications in the biomedical field.


Assuntos
Celulose , Óleos Voláteis , Óleos de Plantas , Celulose/química , Celulose/farmacologia , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Óleos de Plantas/química , Óleos de Plantas/farmacologia , Géis/química , Cicatrização/efeitos dos fármacos , Fabaceae/química , Humanos , Fibroblastos/efeitos dos fármacos , Pelargonium/química , Silanos/química
10.
Sensors (Basel) ; 24(10)2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38793970

RESUMO

Liquid biopsy is expected to become widespread in the coming years thanks to point of care devices, which can include label-free biosensors. The surface functionalization of biosensors is a crucial aspect that influences their overall performance, resulting in the accurate, sensitive, and specific detection of target molecules. Here, the surface of a microring resonator (MRR)-based biosensor was functionalized for the detection of protein biomarkers. Among the several existing functionalization methods, a strategy based on aptamers and mercaptosilanes was selected as the most highly performing approach. All steps of the functionalization protocol were carefully characterized and optimized to obtain a suitable protocol to be transferred to the final biosensor. The functionalization protocol comprised a preliminary plasma treatment aimed at cleaning and activating the surface for the subsequent silanization step. Different plasma treatments as well as different silanes were tested in order to covalently bind aptamers specific to different biomarker targets, i.e., C-reactive protein, SARS-CoV-2 spike protein, and thrombin. Argon plasma and 1% v/v mercaptosilane were found as the most suitable for obtaining a homogeneous layer apt to aptamer conjugation. The aptamer concentration and time for immobilization were optimized, resulting in 1 µM and 3 h, respectively. A final passivation step based on mercaptohexanol was also implemented. The functionalization protocol was then evaluated for the detection of thrombin with a photonic biosensor based on microring resonators. The preliminary results identified the successful recognition of the correct target as well as some limitations of the developed protocol in real measurement conditions.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Silanos , Trombina , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/instrumentação , Aptâmeros de Nucleotídeos/química , Silanos/química , Humanos , Trombina/análise , Proteína C-Reativa/análise , Glicoproteína da Espícula de Coronavírus/química , SARS-CoV-2/isolamento & purificação , Biomarcadores/análise , Propriedades de Superfície , COVID-19/diagnóstico , COVID-19/virologia
11.
ACS Biomater Sci Eng ; 10(5): 3057-3068, 2024 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-38641433

RESUMO

Blood-contacting catheters play a pivotal role in contemporary medical treatments, particularly in the management of cardiovascular diseases. However, these catheters exhibit inappropriate wettability and lack antimicrobial characteristics, which often lead to catheter-related infections and thrombosis. Therefore, there is an urgent need for blood contact catheters with antimicrobial and anticoagulant properties. In this study, we employed tannic acid (TA) and 3-aminopropyltriethoxysilane (APTES) to create a stable hydrophilic coating under mild conditions. Heparin (Hep) and poly(lysine) (PL) were then modified on the TA-APTES coating surface using the layer-by-layer (LBL) technique to create a superhydrophilic TA/APTES/(LBL)4 coating on silicone rubber (SR) catheters. Leveraging the superhydrophilic nature of this coating, it can be effectively applied to blood-contacting catheters to impart antibacterial, antiprotein adsorption, and anticoagulant properties. Due to Hep's anticoagulant attributes, the activated partial thromboplastin time and thrombin time tests conducted on SR/TA-APTES/(LBL)4 catheters revealed remarkable extensions of 276 and 103%, respectively, when compared to uncoated commercial SR catheters. Furthermore, the synergistic interaction between PL and TA serves to enhance the resistance of SR/TA-APTES/(LBL)4 catheters against bacterial adherence, reducing it by up to 99.9% compared to uncoated commercial SR catheters. Remarkably, the SR/TA-APTES/(LBL)4 catheter exhibits good biocompatibility with human umbilical vein endothelial cells in culture, positioning it as a promising solution to address the current challenges associated with blood-contact catheters.


Assuntos
Catéteres , Materiais Revestidos Biocompatíveis , Heparina , Polifenóis , Taninos , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Humanos , Catéteres/microbiologia , Polifenóis/química , Polifenóis/farmacologia , Heparina/química , Heparina/farmacologia , Taninos/química , Taninos/farmacologia , Silanos/química , Silanos/farmacologia , Anticoagulantes/química , Anticoagulantes/farmacologia , Propilaminas/química , Aminas/química , Aminas/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Polilisina/química , Polilisina/farmacologia , Propriedades de Superfície , Interações Hidrofóbicas e Hidrofílicas , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Elastômeros de Silicone/química , Adsorção , Escherichia coli/efeitos dos fármacos
12.
J Med Chem ; 67(8): 6410-6424, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38592014

RESUMO

We report two novel prodrug Pt(IV) complexes with bis-organosilane ligands in axial positions: cis-dichloro(diamine)-trans-[3-(triethoxysilyl)propylcarbamate]platinum(IV) (Pt(IV)-biSi-1) and cis-dichloro(diisopropylamine)-trans-[3-(triethoxysilyl) propyl carbamate]platinum(IV) (Pt(IV)-biSi-2). Pt(IV)-biSi-2 demonstrated enhanced in vitro cytotoxicity against colon cancer cells (HCT 116 and HT-29) compared with cisplatin and Pt(IV)-biSi-1. Notably, Pt(IV)-biSi-2 exhibited higher cytotoxicity toward cancer cells and lower toxicity on nontumorigenic intestinal cells (HIEC6). In preclinical mouse models of colorectal cancer, Pt(IV)-biSi-2 outperformed cisplatin in reducing tumor growth at lower concentrations, with reduced side effects. Mechanistically, Pt(IV)-biSi-2 induced permanent DNA damage independent of p53 levels. DNA damage such as double-strand breaks marked by histone gH2Ax was permanent after treatment with Pt(IV)-biSi-2, in contrast to cisplatin's transient effects. Pt(IV)-biSi-2's faster reduction to Pt(II) species upon exposure to biological reductants supports its superior biological response. These findings unveil a novel strategy for designing Pt(IV) anticancer prodrugs with enhanced activity and specificity, offering therapeutic opportunities beyond conventional Pt drugs.


Assuntos
Antineoplásicos , Compostos Organoplatínicos , Pró-Fármacos , Pró-Fármacos/farmacologia , Pró-Fármacos/química , Pró-Fármacos/síntese química , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Animais , Compostos Organoplatínicos/farmacologia , Compostos Organoplatínicos/química , Compostos Organoplatínicos/síntese química , Ligantes , Camundongos , Linhagem Celular Tumoral , Silanos/química , Silanos/farmacologia , Relação Estrutura-Atividade , Ensaios de Seleção de Medicamentos Antitumorais , Células HT29
13.
Chemosphere ; 358: 142164, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38685326

RESUMO

As the adverse effects of using plastics and perfluorinated alkyl substances become more apparent, there is a growing need for sustainable hydrophobic products. Cellulose and its derivatives are the most abundant and widely used polymers, and cellulose-based products have great potential in industries where plastics and other hydrophobic polymers are used, such as stain-resistant fabrics, food packaging, and oil-water separation applications. In this study, we extracted cellulose from water hyacinth (WH) biomass, known for its negative environmental impact, and converted it into hydrophobic cellulose. This addresses the issue of managing WH waste and creating an environmentally friendly hydrophobic material. Initially, aldehyde groups were introduced through oxidation with periodate, followed by direct octadecyl amine (ODA) grafting onto dialdehyde cellulose (DAC) via a Schiff base condensation. The resulting ODA modified cellulose (ODA-C) was dispersed in ethanol and used to coat various materials, including cotton fabric, cellulose filter paper, and packaging paper. The modified materials showed excellent hydrophobicity as measured by their water contact angles (WCAs), and the application of the coating was demonstrated for oil-water separation, stain-resistant hydrophobic fabric, and paper-based packaging materials. FTIR, XRD, and WCA analysis confirmed the successful modification of cellulose. A high separation efficiency of 99% was achieved for diesel/water separation using modified filter paper (MoFP), under gravity. On application of the coating, cotton fabric became hydrophobic and resisted staining from dye, and paper-based packaging materials became more robust by becoming water-resistant. Overall, the facile synthesis, low cost, high efficiency, and use of environmentally friendly sustainable materials make this a promising strategy for hydrophobically modifying surfaces for a wide range of applications while reducing the menace of water hyacinth.


Assuntos
Biomassa , Celulose , Interações Hidrofóbicas e Hidrofílicas , Silanos , Celulose/química , Celulose/análogos & derivados , Silanos/química , Eichhornia/química , Água/química , Flúor/química , Óleos/química
14.
Biomolecules ; 14(4)2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38672508

RESUMO

Reported herein is the development of assays for the spectrophotometric quantification of biocatalytic silicon-oxygen bond hydrolysis. Central to these assays are a series of chromogenic substrates that release highly absorbing phenoxy anions upon cleavage of the sessile bond. These substrates were tested with silicatein, an enzyme from a marine sponge that is known to catalyse the hydrolysis and condensation of silyl ethers. It was found that, of the substrates tested, tert-butyldimethyl(2-methyl-4-nitrophenoxy)silane provided the best assay performance, as evidenced by the highest ratio of enzyme catalysed reaction rate compared with the background (uncatalysed) reaction. These substrates were also found to be suitable for detailed enzyme kinetics measurements, as demonstrated by their use to determine the Michaelis-Menten kinetic parameters for silicatein.


Assuntos
Biocatálise , Éteres , Silanos , Espectrofotometria , Hidrólise , Espectrofotometria/métodos , Silanos/química , Cinética , Éteres/química , Éteres/metabolismo , Animais , Catepsinas/metabolismo , Catepsinas/química
15.
J Mater Chem B ; 12(15): 3710-3718, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38529668

RESUMO

Meeting the demand for efficient photosensitizers in photodynamic therapy (PDT), a series of iridium(III) complexes decorated with silicane-modified rhodamine (Si-rhodamine) was meticulously designed and synthesized. These complexes demonstrate exceptional PDT potential owing to their strong absorption in the near-infrared (NIR) spectrum, particularly responsive to 808 nm laser stimulation. This feature is pivotal, enabling deep-penetration laser excitation and overcoming depth-related challenges in clinical PDT applications. The molecular structures of these complexes allow for reliable tuning of singlet oxygen generation with NIR excitation, through modification of the cyclometalating ligand. Notably, one of the complexes (4) exhibits a remarkable ROS quantum yield of 0.69. In vivo results underscore the efficacy of 4, showcasing significant tumor regression at depths of up to 8.4 mm. This study introduces a promising paradigm for designing photosensitizers capable of harnessing NIR light effectively for deep PDT applications.


Assuntos
Fotoquimioterapia , Fármacos Fotossensibilizantes , Silanos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/química , Fotoquimioterapia/métodos , Irídio/farmacologia , Irídio/química , Rodaminas , Linhagem Celular Tumoral , Raios Infravermelhos
16.
Biomed Phys Eng Express ; 10(4)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38479000

RESUMO

Diagnosis of diseases with low facilities, speed, accuracy and sensitivity is an important matter in treatment. Bioprobes based on iron oxide nanoparticles are a good candidate for early detection of deadly and infectious diseases such as tetanus due to their high reactivity, biocompatibility, low production cost and sample separation under a magnetic field. In this study, silane groups were coated on surface of iron oxide nanoparticles using tetraethoxysilane (TEOS) hydrolysis. Also, NH2groups were generated on the surface of silanized nanoparticles using 3-aminopropyl triethoxy silane (APTES). Antibody was immobilized on the surface of silanized nanoparticles using TCT trichlorothriazine as activator. Silanization and stabilized antibody were investigated by using of FT-IR, EDX, VSM, SRB technique. UV/vis spectroscopy, fluorescence, agglutination test and ELISA were used for biosensor performance and specificity. The results of FT-IR spectroscopy showed that Si-O-Si and Si-O-Fe bonds and TCT chlorine and amine groups of tetanus anti-toxoid antibodies were formed on the surface of iron oxide nanoparticles. The presence of Si, N and C elements in EDX analysis confirms the silanization of iron oxide nanoparticles. VSM results showed that the amount of magnetic nanoparticles after conjugation is sufficient for biological applications. Antibody stabilization on nanoparticles increased the adsorption intensity in the uv/vis spectrometer. The fluorescence intensity of nano bioprobe increased in the presence of 10 ng ml-1. Nanobio probes were observed as agglomerates in the presence of tetanus toxoid antigen. The presence of tetanus antigen caused the formation of antigen-nanobioprobe antigen complex. Identification of this complex by HRP-bound antibody confirmed the specificity of nanobioprobe. Tetanus magnetic nanobioprobe with a diagnostic limit of 10 ng ml-1of tetanus antigen in a short time can be a good tool in LOC devices and microfluidic chips.


Assuntos
Técnicas Biossensoriais , Propilaminas , Silanos , Toxoide Tetânico , Toxoide Tetânico/química , Toxoide Tetânico/imunologia , Silanos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Técnicas Biossensoriais/métodos , Propilaminas/química , Humanos , Ensaio de Imunoadsorção Enzimática , Nanopartículas Magnéticas de Óxido de Ferro/química , Tétano/diagnóstico , Tétano/prevenção & controle , Nanopartículas de Magnetita/química , Anticorpos Imobilizados/química , Anticorpos Imobilizados/imunologia , Limite de Detecção , Ferro/química , Testes de Aglutinação/métodos
17.
Sci Rep ; 14(1): 5946, 2024 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-38467715

RESUMO

The use of dendrimers as drug and nucleic acid delivery systems requires knowledge of their interactions with objects on their way to the target. In the present work, we investigated the interaction of a new class of carbosilane dendrimers functionalized with polyphenolic and caffeic acid residues with human serum albumin, which is the most abundant blood protein. The addition of dendrimers to albumin solution decreased the zeta potential of albumin/dendrimer complexes as compared to free albumin, increased density of the fibrillary form of albumin, shifted fluorescence spectrum towards longer wavelengths, induced quenching of tryptophan fluorescence, and decreased ellipticity of circular dichroism resulting from a reduction in the albumin α-helix for random coil structural form. Isothermal titration calorimetry showed that, on average, one molecule of albumin was bound by 6-10 molecules of dendrimers. The zeta size confirmed the binding of the dendrimers to albumin. The interaction of dendrimers and albumin depended on the number of caffeic acid residues and polyethylene glycol modifications in the dendrimer structure. In conclusion, carbosilane polyphenolic dendrimers interact with human albumin changing its structure and electrical properties. However, the consequences of such interaction for the efficacy and side effects of these dendrimers as drug/nucleic acid delivery system requires further research.


Assuntos
Ácidos Cafeicos , Dendrímeros , Ácidos Nucleicos , Humanos , Albumina Sérica Humana/metabolismo , Dendrímeros/química , Silanos/química
18.
Carbohydr Polym ; 329: 121794, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38286531

RESUMO

Cellulose acetate (CA)-based electrospun nanofiber aerogel (ENA) has drawn extensive attention for wastewater remediation due to its unique separation, inherent porosity and biodegradability. However, the low mechanical strength, poor durability, and limited adsorption ability hinder its further applications. We herein propose using silane-modified ENA, namely T-CA@Si@ZIF-67 (T-ENA), with enhanced resilience, hydrophobicity, durability and hetero-catalysis to remediate a complex wastewater containing oil and drug residues. The robust T-ENA was fabricated by pre-doping tetraethyl orthosilicate (TEOS) and ligand in its spinning precursors, followed by in-situ anchoring of porous ZIF-67 on the electrospun nanofibers (ENFs) via seeding method before freeze-drying and thermal curing (T). Results show that the T-ENA displays enhanced mechanical stability/resilience and hydrophobicity without compromise of its high porosity (>98 %) and low density (10 mg/cm3) due to the silane cross-linking. As a result, the hydrophobic T-ENA shows over 99 % separation efficiency towards different oil-water solutions. Meanwhile, thanks to the enhanced adsorption-catalytic ability and the activation of peroxymonosulfate (PMS) from the porous ZIF-67, fast degradation of carbamazepine (CBZ) residue in the wastewater can be achieved within 20 min. This work might provide a novel strategy for developing CA aerogels to remove organic pollutants.


Assuntos
Celulose/análogos & derivados , Resíduos de Drogas , Nanofibras , Resiliência Psicológica , Nanofibras/química , Géis/química , Águas Residuárias , Silanos , Interações Hidrofóbicas e Hidrofílicas
19.
J Mech Behav Biomed Mater ; 151: 106372, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38211500

RESUMO

OBJECTIVES: This study investigated the impact of using γ-methacryloxypropyl trimethoxy silane (MPS) for surface silanization of poly (urea-formaldehyde) (PUF) microcapsules which enclose a healing liquid of "triethylene glycol dimethacrylate (TEGDMA) and N,N dihydroxyethyl-p-toluidine (DHEPT)" on some mechanical properties of an experimental dental composite as well as its self-healing efficiency. METHODS: Synthesis of PUF microcapsules was done via in situ polymerization, followed by silanization with MPS silane. Silanized and non-silanized microcapsules were incorporated into a composite containing 30% polymer matrix and 70% fillers at different weight percentages (0%, 5%, 7.5% and 10%). The composite strength and elastic modulus were evaluated by Flexural testing. Fracture toughness KIc and self-healing efficiency were assessed by utilizing the "single edge notched beam" method. RESULTS: Flexural strength of all groups containing silanized microcapsules was non-significantly different from control group without microcapsules. However, in contrast to control group, all groups containing non-silanized microcapsules displayed considerably decreased flexural strength. Adding silanized and non-silanized microcapsules didn't show a significant change in the KIc-virgin. The silanized microcapsules' groups achieved a self-healing efficiency of about 49-77% recovery in KIc-virgin compared to 38-69% for their non-silanized counterparts. SIGNIFICANCE: In order to increase the interfacial adhesion with the polymer matrix, improve the mechanical properties, and increase the efficiency of self-healing of dental resin composite, PUF microcapsules were silanized for the first time in the dental field using MPS silane. This innovative silanized microcapsule-containing self-healing composite may hold promise for repairing the damage caused by restorative cracks and extending their service life.


Assuntos
Resinas Compostas , Resistência à Flexão , Cápsulas , Silanos , Polímeros , Formaldeído , Teste de Materiais , Propriedades de Superfície
20.
Photobiomodul Photomed Laser Surg ; 42(1): 20-48, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37862260

RESUMO

Background/objective: This systematic review and meta-analysis aimed to assess how laser conditioning affected brackets bonded to dental ceramics' shear bond strength (SBS). Materials and methods: The study was conducted by searching Pubmed/Medline, Scopus, Embase, Web of Science, the Cochrane Library, and Google Scholar up to September 14, 2022. In addition, the reference lists of the relevant articles were checked manually. Articles that compared SBS of laser-treated feldspathic, lithium disilicate, or zirconia surfaces with other standard techniques for bonding metal or ceramic orthodontic brackets were considered. Using a random-effects model, data pooling was carried out as the weighted mean difference (WMD). Results: This study initially contained 1717 reports, and following review, 32 articles were deemed suitable for our meta-analysis. The pooling results showed that the treatments with lasers such as "Er:YAG" [WMD = -1.12 MPa; 95% confidence interval (CI): -1.93 to -0.31], "Er:YAG + Silane" (WMD = -3.08 MPa; 95% CI: -4.77 to -1.40), and "Nd: YAG + Silane" (WMD = -2.58 MPa; 95% CI: -3.76 to -1.40) had statistically significant lower adhesion values compared with controls. Contrarily, "Ti:Sapphire femtosecond" demonstrated significantly higher bonding values (WMD = 0.94 MPa; 95% CI: 0.29-1.60). In contrast, other interventions obtained no statistically significant difference in SBS. Conclusions: Most of the laser groups showed results comparable with those of conventional approaches. Although more research is necessary for definitive conclusions, laser treatment may be an effective option for treating the surfaces of ceramic materials.


Assuntos
Cerâmica , Lasers , Braquetes Ortodônticos , Cerâmica/química , Microscopia Eletrônica de Varredura , Resistência ao Cisalhamento , Silanos/química , Propriedades de Superfície
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