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1.
J Nanobiotechnology ; 21(1): 405, 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37919778

RESUMO

Chronic Kidney Disease (CKD) which involves gradual loss of kidney function is characterized by low levels of a glycoprotein called Erythropoietin (EPO) that leads to red blood cell  deficiency and anemia. Recombinant human EPO (rhEPO) injections that are administered intravenously or subcutaneously is the current gold standard for treating CKD. The rhEPO injections have very short half-lives and thus demands frequent administration with a risk of high endogenous EPO levels leading to severe side effects that could prove fatal. To this effect, this work provides a novel approach of using lamellar inorganic solids with a brucite-like structure for controlling the release of protein therapeutics such as rhEPO in injectable hydrogels. The nanoengineered injectable system was formulated by incorporating two-dimensional layered double hydroxide (LDH) clay materials with a high surface area into alginate hydrogels for sustained delivery. The inclusion of LDH in the hydrogel network not only improved the mechanical properties of the hydrogels (5-30 times that of alginate hydrogel) but also exhibited a high binding affinity to proteins without altering their bioactivity and conformation. Furthermore, the nanoengineered injectable hydrogels (INHs) demonstrated quick gelation, injectability, and excellent adhesion properties on human skin. The in vitro release test of EPO from conventional alginate hydrogels (Alg-Gel) showed 86% EPO release within 108 h while INHs showed greater control over the initial burst and released only 24% of EPO in the same incubation time. INH-based ink was successfully used for 3D printing, resulting in scaffolds with good shape fidelity and stability in cell culture media. Controlled release of EPO from INHs facilitated superior angiogenic potential in ovo (chick chorioallantoic membrane) compared to Alg-Gel. When subcutaneously implanted in albino mice, the INHs formed a stable gel in vivo without inducing any adverse effects. The results suggest that the proposed INHs in this study can be utilized as a minimally invasive injectable platform or as 3D printed patches for the delivery of protein therapeutics to facilitate tissue regeneration.


Assuntos
Hidrogéis , Insuficiência Renal Crônica , Camundongos , Animais , Humanos , Hidrogéis/química , Engenharia Tecidual/métodos , Preparações de Ação Retardada/farmacologia , Alginatos/química , Hidróxidos
2.
Microb Pathog ; 128: 363-373, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30684638

RESUMO

Pseudomonas aeruginosa is an opportunistic human pathogen which exhibits its property of pathogenesis due to several factors, including the formation of biofilm and production of several virulence factors. Development of resistance properties against antibiotics leads to the discovery of certain alternative strategies to combat its pathogenesis. In the present study, a highly stable, biocompatible and water soluble nanocomposites (NCs) are synthesized from chitosan (CS) and the polypyrrole (PPy). The resultant chitosan-polypyrrole nanocomposites (CS-PPy NCs) inhibit the establishment of biofilm and also eradicate the preformed matured biofilm formed by P. aeruginosa. CS-PPy NCs inhibit the hemolytic and protease activities of P. aeruginosa. The NCs significantly reduce the production of many virulence factors such as pyocyanin, pyroverdine and rhamnolipid. CS-PPy NCs also suppress the bacterial motility such as swimming and swarming. The present study showed that highly stable CS-PPy NCs act as a potent antibiofilm and antivirulence drug for the treatment of P. aeruginosa infection.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Quitosana/farmacologia , Nanocompostos/química , Polímeros/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pirróis/farmacologia , Eritrócitos , Glicolipídeos/farmacologia , Hemólise/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Peptídeo Hidrolases/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Piocianina/farmacologia , Fatores de Virulência
3.
Microb Pathog ; 135: 103623, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31325574

RESUMO

The infection caused by Pseudomonas aeruginosa is a serious concern in human health. The bacterium is an opportunistic pathogen which has been reported to cause nosocomial and chronic infections through biofilm formation and synthesis of several toxins and virulence factors. Furthermore, the formation of biofilm by P. aeruginosa is known as one of the resistance mechanisms against conventional antibiotics. Natural compounds from marine resources have become one of the simple, cost-effective, biocompatible and non-toxicity for treating P. aeruginosa biofilm-related infections. Furthermore, hybrid formulation with nanomaterials such as nanoparticles becomes an effective alternative strategy to minimize the drug toxicity problem and cytotoxicity properties. For this reason, the present study has employed chitosan oligosaccharide for the synthesis of chitosan oligosaccharide-capped gold nanoparticles (COS-AuNPs). The synthesized COS-AuNPs were then characterized by using UV-Visible spectroscopy, Dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), Field emission transmission electron microscopy (FE-TEM), and Energy dispersive X-ray diffraction (EDX). The synthesized COS-AuNPs were applied for inhibiting P. aeruginosa biofilm formation. Results have shown that COS-AuNPs exhibited inhibition to biofilm as well as eradication to pre-existing mature biofilm. Simultaneously, COS-AuNPs were also able to reduce bacterial hemolysis and different virulence factors produced by P. aeruginosa. Overall, the present study concluded that the hybrid nanoformulation such as COS-AuNPs could act as a potential agent to exhibit inhibitory properties against the P. aeruginosa pathogenesis arisen from biofilm formation.


Assuntos
Biofilmes/efeitos dos fármacos , Ouro/química , Nanopartículas Metálicas/química , Oligossacarídeos/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Antibacterianos/farmacologia , Quitosana/química , Cinética , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Pseudomonas aeruginosa/crescimento & desenvolvimento , Espectroscopia de Infravermelho com Transformada de Fourier , Fatores de Virulência , Difração de Raios X
4.
J Nanosci Nanotechnol ; 19(4): 1951-1958, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30486935

RESUMO

We have prepared a core-shell magnetic silica-coated hydroxyapatite, Fe3O4@SiO2@HAp composite materials for pH-responsive drug delivery applications. Captopril (Cap) and ibuprofen (Ibu) were chosen as model hydrophilic and hydrophobic drugs, respectively. The drugs were encapsulated into the Fe3O4@SiO2@HAp composite via electrostatic interactions with existing amine and carboxylic acid groups during calcium phosphate shell formation. The formation of calcium phosphate shell not only protects the encapsulated drugs from leaching but also controls the release rate of drugs from the composite system depending on various pH conditions. We have tested the release behavior of Cap and Ibu drugs under different pH conditions such as neutral pH (pH 7.4) and acidic pH (pH 5.0), respectively. The study result reveals that the synthesized Fe3O4@SiO2@HAp composite is suitable for release of both water soluble and water insoluble drugs based on a pH-responsive controlled manner.


Assuntos
Preparações Farmacêuticas , Dióxido de Silício , Sistemas de Liberação de Medicamentos , Durapatita , Fenômenos Magnéticos , Magnetismo
5.
Mar Drugs ; 17(4)2019 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-30987163

RESUMO

The emergence of antibiotic resistance in Pseudomonas aeruginosa due to biofilm formation has transformed this opportunistic pathogen into a life-threatening one. Biosynthesized nanoparticles are increasingly being recognized as an effective anti-biofilm strategy to counter P. aeruginosa biofilms. In the present study, gold nanoparticles (AuNPs) were biologically synthesized and stabilized using fucoidan, which is an active compound sourced from brown seaweed. Biosynthesized fucoidan-stabilized AuNPs (F-AuNPs) were subjected to characterization using UV-visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), field emission transmission electron microscopy (FE-TEM), dynamic light scattering (DLS), and energy dispersive X-ray diffraction (EDX). The biosynthesized F-AuNPs were then evaluated for their inhibitory effects on P. aeruginosa bacterial growth, biofilm formation, virulence factor production, and bacterial motility. Overall, the activities of F-AuNPs towards P. aeruginosa were varied depending on their concentration. At minimum inhibitory concentration (MIC) (512 µg/mL) and at concentrations above MIC, F-AuNPs exerted antibacterial activity. In contrast, the sub-inhibitory concentration (sub-MIC) levels of F-AuNPs inhibited biofilm formation without affecting bacterial growth, and eradicated matured biofilm. The minimum biofilm inhibition concentration (MBIC) and minimum biofilm eradication concentration (MBEC) were identified as 128 µg/mL. Furthermore, sub-MICs of F-AuNPs also attenuated the production of several important virulence factors and impaired bacterial swarming, swimming, and twitching motilities. Findings from the present study provide important insights into the potential of F-AuNPs as an effective new drug for controlling P. aeruginosa-biofilm-related infections.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Ouro/farmacologia , Polissacarídeos/farmacologia , Pseudomonas aeruginosa/fisiologia , Antibacterianos/química , Composição de Medicamentos/métodos , Farmacorresistência Bacteriana/efeitos dos fármacos , Estabilidade de Medicamentos , Ouro/química , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Phaeophyceae/química , Polissacarídeos/química , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/efeitos dos fármacos , Alga Marinha/química
6.
Crit Rev Biotechnol ; 38(5): 745-761, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29124966

RESUMO

In recent years, marine natural pigments have emerged as a powerful alternative in the various fields of food, cosmetic, and pharmaceutical industries because of their excellent biocompatibility, bioavailability, safety, and stability. Marine organisms are recognized as a rich source of natural pigments such as chlorophylls, carotenoids, and phycobiliproteins. Numerous studies have shown that marine natural pigments have considerable medicinal potential and promising applications in human health. In this review, we summarize the marine natural pigments as potential sources for therapeutic applications, including: antioxidant, anticancer, antiangiogenic, anti-obesity, anti-inflammatory activities, drug delivery, photothermal therapy (PTT), photodynamic therapy (PDT), photoacoustic imaging (PAI), and wound healing. Marine natural pigments will offer a better platform for future theranostic applications.


Assuntos
Organismos Aquáticos/química , Carotenoides , Clorofila , Animais , Anti-Inflamatórios , Fármacos Antiobesidade , Antineoplásicos , Carotenoides/química , Carotenoides/uso terapêutico , Clorofila/química , Clorofila/uso terapêutico , Humanos , Camundongos , Substâncias Protetoras
7.
Crit Rev Microbiol ; 42(2): 209-21, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25430521

RESUMO

Nanotechnology is gaining tremendous attention in the present century due to its expected impact on many important areas such as medicine, energy, electronics, and space industries. In this context, actinobacterial biosynthesis of nanoparticles is a reliable, eco-friendly, and important aspect of green chemistry approach that interconnects microbial biotechnology and nanobiotechnology. Antibiotics produced by actinobacteria are popular in almost all the therapeutic measures and it is known that these microbes are also helpful in the biosynthesis of nanoparticles with good surface and size characteristics. In fact, actinobacteria are efficient producers of nanoparticles that show a range of biological properties, namely, antibacterial, antifungal, anticancer, anti-biofouling, anti-malarial, anti-parasitic, antioxidant, etc. This review describes the potential use of the actinobacteria as the novel sources for the biosynthesis of nanoparticles with improved biomedical applications.


Assuntos
Actinobacteria/fisiologia , Biotecnologia , Nanopartículas/metabolismo , Nanotecnologia , Anti-Infecciosos/química , Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Antioxidantes/química , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Espaço Extracelular/metabolismo , Humanos , Espaço Intracelular/metabolismo , Nanopartículas/química , Nanopartículas/classificação , Nanopartículas/ultraestrutura
8.
Crit Rev Microbiol ; 42(6): 1007-19, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26920850

RESUMO

The use of marine microorganisms as potential biofactories for green synthesis of metallic nanoparticles is a relatively new field of research with considerable prospects. This method is eco-friendly, time saving, and inexpensive and can be easily scaled up for large-scale synthesis. The increasing need to develop simple, nontoxic, clean, and environmentally safe production methods for nanoparticles and to decrease environmental impact, minimize waste, and increase energy productivity has become important in this field. Marine microorganisms are tiny organisms that live in marine ecosystems and account for >98% of biomass of the world's ocean. Marine microorganisms synthesize metallic nanoparticles either intracellularly or extracellularly. Marine microbially-produced metallic nanoparticles have received considerable attention in recent years because of their expected impact on various applications such as medicine, energy, electronic, and space industries. The present review discusses marine microorganisms as potential biofactories for the green synthesis of metallic nanoparticles and their potential applications.


Assuntos
Bactérias/metabolismo , Fungos/metabolismo , Química Verde/métodos , Nanopartículas Metálicas/química , Metais/metabolismo , Água do Mar/microbiologia , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Fungos/classificação , Fungos/genética , Fungos/isolamento & purificação , Metais/química
9.
Molecules ; 21(11)2016 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-27827890

RESUMO

C-phycocyanin, a natural blue-colored pigment-protein complex was explored as a novel photosensitizer for use in low-level laser therapy under 625-nm laser illumination. C-phycocyanin produced singlet oxygen radicals and the level of reactive oxygen species (ROS) were raised in extended time of treatment. It did not exhibit any visible toxic effect in the absence of light. Under 625-nm laser irradiation, c-phycocyanin generated cytotoxic stress through ROS induction, which killed MDA-MB-231 breast cancer cells depending on concentrations. Different fluorescent staining of laser-treated cells explored apoptotic cell death characteristics like the shrinking of cells, cytoplasmic condensation, nuclei cleavage, and the formation of apoptotic bodies. In conclusion, phycocyanin is a non-toxic fluorescent pigment that can be used in low-level light therapy.


Assuntos
Neoplasias da Mama/metabolismo , Fármacos Fotossensibilizantes/farmacologia , Ficocianina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Apoptose , Neoplasias da Mama/radioterapia , Linhagem Celular Tumoral , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Humanos , Terapia com Luz de Baixa Intensidade
10.
Crit Rev Microbiol ; 41(2): 261-72, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24495095

RESUMO

Actinobacteria have potential as important new sources of enzyme inhibitors. Enzyme inhibitors have great demand in medicine, agriculture and biotechnology. In medicine, enzyme inhibitors can be used as therapeutic agents for bacterial, fungal, viral and parasitic diseases as well as treating cancer, neurodegenerative, immunological and cardiovascular diseases. Enzyme inhibitors are also valuable for the control of carbohydrate-dependent diseases such as diabetes, obesity and hyperlipidemia and melanogenesis in skin. They can be also involved in crop protection against plant pathogens, herbivorous pests and abiotic stresses such as drought. In this review, we discuss about several actinobacterial enzyme inhibitors with various industrial uses and biotechnological applications.


Assuntos
Actinobacteria/metabolismo , Produtos Biológicos/metabolismo , Produtos Biológicos/farmacologia , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Agricultura/métodos , Produtos Biológicos/isolamento & purificação , Testes Diagnósticos de Rotina/métodos , Tratamento Farmacológico/métodos , Inibidores Enzimáticos/isolamento & purificação
11.
Mar Drugs ; 13(11): 6818-37, 2015 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-26569267

RESUMO

Marine actinobacteria-produced fucoidanases have received considerable attention as one of the major research topics in recent years, particularly for the medical exploitation of fucoidans and their degradation products. The present study describes the optimization and production of a novel fucoidanase for the green synthesis of gold nanoparticles and its biological applications. The production of fucoidanase was optimized using Streptomyces sp. The medium components were selected in accordance with the Plackett-Burman design and were further optimized via response surface methodology. The fucoidanase was statistically optimized with the most significant factors, namely wheat bran 3.3441 g/L, kelp powder 0.7041 g/L, and NaCl 0.8807 g/L, respectively. The biosynthesized gold nanoparticles were determined by UV-vis spectroscopy and were further characterized by X-ray diffraction analysis, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, energy dispersive X-ray analysis, and high-resolution transmission electron microscopy. Furthermore, the biosynthesized gold nanoparticles exhibited a dose-dependent cytotoxicity against HeLa cells and the inhibitory concentration (IC50) was found to be 350 µg/mL at 24 h and 250 µg/mL at 48 h. Therefore, the production of novel fucoidanase for the green synthesis of gold nanoparticles has comparatively rapid, less expensive and wide application to anticancer therapy in modern medicine.


Assuntos
Glicosídeo Hidrolases/metabolismo , Ouro/química , Nanopartículas Metálicas/química , Streptomyces/enzimologia , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Relação Dose-Resposta a Droga , Feminino , Células HeLa , Humanos , Concentração Inibidora 50 , Nanopartículas Metálicas/administração & dosagem , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Espectroscopia de Infravermelho com Transformada de Fourier , Neoplasias do Colo do Útero/tratamento farmacológico , Difração de Raios X
12.
Bioprocess Biosyst Eng ; 38(6): 1167-77, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25645365

RESUMO

Advancement of biological process for the synthesis of bionanoparticles is evolving into a key area of research in nanotechnology. The present study deals with the biosynthesis, characterization of gold bionanoparticles by Nocardiopsis sp. MBRC-48 and evaluation of their antimicrobial, antioxidant and cytotoxic activities. The gold bionanoparticles obtained were characterized by UV-visible spectroscopy, X-ray diffraction analysis, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, energy dispersive X-ray analysis and transmission electron microscopy (TEM). The synthesized gold bionanoparticles were spherical in shape with an average of 11.57 ± 1.24 nm as determined by TEM and dynamic light scattering (DLS) particle size analyzer, respectively. The biosynthesized gold nanoparticles exhibited good antimicrobial activity against pathogenic microorganisms. It showed strong antioxidant activity as well as cytotoxicity against HeLa cervical cancer cell line. The present study demonstrated the potential use of the marine actinobacterial strain of Nocardiopsis sp. MBRC-48 as an important source for gold nanoparticles with improved biomedical applications including antimicrobial, antioxidant as well as cytotoxic agent.


Assuntos
Anti-Infecciosos/farmacologia , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Ouro/química , Nanopartículas Metálicas , Actinobacteria , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Testes de Sensibilidade Microbiana , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
13.
Bioprocess Biosyst Eng ; 37(5): 783-97, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24061563

RESUMO

A potential glycolipid biosurfactant producer Streptomyces sp. MAB36 was isolated from marine sediment samples. Medium composition and culture conditions for the glycolipid biosurfactant production by Streptomyces sp. MAB36 were optimized, using two statistical methods: Plackett-Burman design was applied to find out the key ingredients and conditions for the best yield of glycolipid biosurfactant production and central composite design was used to optimize the concentration of the four significant variables, starch, casein, crude oil and incubation time. Fructose and yeast extract were the best carbon and nitrogen sources for the production of the glycolipid biosurfactant. Biochemical characterizations including FTIR and MS studies suggested the glycolipid nature of the biosurfactant. The isolated glycolipid biosurfactant reduced the surface tension of water from 73.2 to 32.4 mN/m. The purified glycolipid biosurfactant showed critical micelle concentrations of 36 mg/l. The glycolipid biosurfactant was effective at very low concentrations over a wide range of temperature, pH, and NaCl concentration. The purified glycolipid biosurfactant showed strong antimicrobial activity. Thus, the strain Streptomyces sp. MAB36 has proved to be a potential source of glycolipid biosurfactant that could be used for the bioremediation processes in the marine environment.


Assuntos
Organismos Aquáticos/crescimento & desenvolvimento , Glicolipídeos/biossíntese , Streptomyces/crescimento & desenvolvimento , Tensoativos/metabolismo
14.
Bioprocess Biosyst Eng ; 37(8): 1591-7, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24525832

RESUMO

In the present study, we report rapid biological synthesis of gold nanoparticles (Au NPs) using a novel marine brown alga Ecklonia cava (Family: Lessoniaceae) by the reduction of chloroauric acid. The formation of Au NPs reaction was complete within 1 min at 80 °C and physiochemically characterized with different analytical techniques. FTIR spectroscopy revealed that Au NPs were functionalized with biomolecules that have primary amine group, hydroxyl group and other stabilizing functional groups. X-ray diffraction pattern showed high purity and face-centered cubic structure of Au NPs. Microscopy results showed that these Au NPs are formed with shapes like spherical and triangular with an average size of 30 ± 0.25 nm. Synthesized Au NPs showed good antimicrobial and biocompatibility with human keratinocyte cell line. Thus, physiochemical characteristic results suggest that Au NPs will have promising biomedical applications in different area such as drug delivery, tissue engineering, biosensor, etc.


Assuntos
Cloretos/química , Compostos de Ouro/química , Ouro/química , Nanopartículas Metálicas/química , Humanos , Oxirredução , Tamanho da Partícula , Phaeophyceae
15.
Pharmaceutics ; 16(1)2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38276508

RESUMO

Precision diagnosis-guided efficient treatment is crucial to extending the lives of cancer patients. The integration of surface-enhanced Raman scattering (SERS) imaging and phototherapy into a single nanoplatform has been considered a more accurate diagnosis and treatment strategy for cancer nanotheranostics. Herein, we constructed a new type of mesoporous silica-layered gold nanorod core@silver shell nanostructures loaded with methylene blue (GNR@Ag@mSiO2-MB) as a multifunctional nanotheranostic agent for intracellular SERS imaging and phototherapy. The synthesized GNR@Ag@mSiO2-MB nanostructures possessed a uniform core-shell structure, strong near-infrared (NIR) absorbance, photothermal conversion efficiency (65%), dye loading ability, SERS signal, and Raman stability under phototherapy conditions. Under single 785 nm NIR laser irradiation, the intracellular GNR@Ag@mSiO2-MB nanostructures were dramatically decreased to <9%, which showed excellent photothermal and photodynamic effects toward cancer cell killing, indicating that the combination of photothermal therapy (PTT) and photodynamic therapy (PDT) of the GNR@Ag@mSiO2-MB nanostructures could greatly enhance the therapeutic efficacy of cancer cell death. GNR@Ag@mSiO2-MB nanostructures demonstrated a strong Raman signal at 450 and 502 cm-1, corresponding to the δ(C-N-C) mode, suggesting that the Raman bands of GNR@Ag@mSiO2-MB nanostructures were more efficient to detect CT-26 cell SERS imaging with high specificity. Our results indicate that GNR@Ag@mSiO2-MB nanostructures offer an excellent multifunctional nanotheranostic platform for SERS imaging and synergistic anticancer phototherapy in the future.

16.
Int J Biol Macromol ; 259(Pt 1): 129165, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38163501

RESUMO

This work aimed to prepare multifunctional aptamer-conjugated, photothermally responsive 5-fluorouracil (5fu)-loaded chitosan-bimetallic (Au/Pd) nanoparticles (APT-CS-5fu-Au/Pd NPs) for improved cytotoxicity in two cancer cell lines (PANC-1 and MDA-MD 231). The CS-5fu-Au/Pd NPs were polydispersed with a size of 34.43 ± 1.59 nm. FTIR analysis indicated the presence of CS, 5fu in CS-5fu-Au/Pd NPs. The 2 theta degrees in CS-5fu-Au/Pd NPs accounted for CS and Au/Pd. Additionally, AGE revealed the conjugation of APT in CS-5fu-Au/Pd NPs. The APT-CS-5fu-Au/Pd NPs (180 µg/mL) with NIR treatment increased the temperature to >50 °C. The optimized 5fu input was 0.075 % in CS-5fu-Au/Pd NPs, exhibiting a hydrodynamic size of 112.96 ± 17.23 nm, DEE of 64.2 ± 3.77 %, and DLE of 11.1 ± 0.65 %. A higher level of 5fu release (69.8 ± 2.78 %) was observed under pH 5.4 at 74 h. In conclusion, NIR-APT-CS-5fu-Au/Pd NPs did not cause toxicity to RBC and Egg CAM, but increased cytotoxicity in MDA-MB 231 and PANC-1 cells by triggering oxidative stress-mediated cell death.


Assuntos
Quitosana , Nanopartículas , Neoplasias de Mama Triplo Negativas , Humanos , Fluoruracila/farmacologia , Morte Celular
17.
Pharmaceutics ; 16(2)2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38399337

RESUMO

Phototherapies, such as photothermal therapy (PTT) and photodynamic therapy (PDT), combined with novel all-in-one light-responsive nanocomposites have recently emerged as new therapeutic modalities for the treatment of cancer. Herein, we developed novel all-in-one triphenylphosphonium-functionalized gold nanorod/zinc oxide core-shell nanocomposites (CTPP-GNR@ZnO) for mitochondrial-targeted PTT/PDT owing to their good biocompatibility, tunable and high optical absorption, photothermal conversion efficiency, highest reactive oxygen species (ROS) generation, and high mitochondrial-targeting capability. Under laser irradiation of 780 nm, the CTPP-GNR@ZnO core-shell nanocomposites effectively produced heat in addition to generating ROS to induce cell death, implying a synergistic effect of mild PTT and PDT in combating cancer. Notably, the in vitro PTT/PDT effect of CTPP-GNR@ZnO core-shell nanocomposites exhibited effective cell ablation (95%) and induced significant intracellular ROS after the 780 nm laser irradiation for 50 min, indicating that CTPP in CTPP-GNR@ZnO core-shell nanocomposites can specifically target the mitochondria of CT-26 cells, as well as generate heat and ROS to completely kill cancer cells. Overall, this light-responsive nanocomposite-based phototherapy provides a new approach for cancer synergistic therapy.

18.
ACS Nano ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38975706

RESUMO

Electrolytic ablation (EA) is a burgeoning treatment for solid tumors, in which electrical energy catalyzes a chemical reaction to generate reactive species that can eradicate cancer cells. However, the application of this technique has been constrained owing to the limited spatial effectiveness and complexity of the electrode designs. Therefore, the incorporation of nanotechnology into EA is anticipated to be a significant improvement. Herein, we present a therapeutic approach based on difructose dianhydride IV-conjugated polyethylenimine-polyethylene glycol-modified gold nanorods as electric nanoantennas and nanoelectrocatalysts for EA. We demonstrate that square-wave direct current (DC) fields trigger a reaction between water molecules and chloride ions on the gold nanorod surface, generating electrolytic products including hydrogen, oxygen, and chlorine gases near the electrodes, changing the pH, and inducing cell death. These electric nanoantennas showed significant efficacy in treating colorectal cancer both in vitro and in vivo after DC treatment. These findings clearly indicate that gold nanoantennas enhance the effectiveness of EA by creating a localized electric field and catalyzing electrolytic reactions for the induction of locoregional pH changes within the tumor. By overcoming the limitations of traditional EA and offering an enhanced level of tumor specificity and control, this nanotechnology-integrated approach advances further innovations in cancer therapies.

19.
World J Microbiol Biotechnol ; 29(10): 1737-50, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23595596

RESUMO

Melanins are enigmatic pigments that are produced by a wide variety of microorganisms including several species of bacteria and fungi. Melanins are biological macromolecules with multiple important functions, yet their structures are not well understood. Melanins are frequently used in medicine, pharmacology, and cosmetics preparations. Melanins also have great application potential in agriculture industry. They have several biological functions including photoprotection, thermoregulation, action as free radical sinks, cation chelators, and antibiotics. Plants and insects incorporate melanins as cell wall and cuticle strengtheners, respectively. Actinobacteria are the most economically as well as biotechnologically valuable prokaryotes. However, the melanin properties are, in general, poorly understood. In this review an evaluation is made on the present state of research on actinobacterial melanins and its perspectives. The highlights include the production and biotechnological applications of melanins in agriculture, food, cosmetic and medicinal fields. With increasing advancement in science and technology, there would be greater demands in the future for melanins produced by actinobacteria from various sources.


Assuntos
Actinobacteria/metabolismo , Proteínas de Bactérias/metabolismo , Melaninas/metabolismo , Agricultura/métodos , Proteínas de Bactérias/isolamento & purificação , Técnicas Cosméticas , Indústria Alimentícia/métodos , Melaninas/isolamento & purificação , Tecnologia Farmacêutica/métodos
20.
Pharmaceutics ; 15(5)2023 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-37242798

RESUMO

Novel biocompatible and efficient photothermal (PT) therapeutic materials for cancer treatment have recently garnered significant attention, owing to their effective ablation of cancer cells, minimal invasiveness, quick recovery, and minimal damage to healthy cells. In this study, we designed and developed calcium ion-doped magnesium ferrite nanoparticles (Ca2+-doped MgFe2O4 NPs) as novel and effective PT therapeutic materials for cancer treatment, owing to their good biocompatibility, biosafety, high near-infrared (NIR) absorption, easy localization, short treatment period, remote controllability, high efficiency, and high specificity. The studied Ca2+-doped MgFe2O4 NPs exhibited a uniform spherical morphology with particle sizes of 14.24 ± 1.32 nm and a strong PT conversion efficiency (30.12%), making them promising for cancer photothermal therapy (PTT). In vitro experiments showed that Ca2+-doped MgFe2O4 NPs had no significant cytotoxic effects on non-laser-irradiated MDA-MB-231 cells, confirming that Ca2+-doped MgFe2O4 NPs exhibited high biocompatibility. More interestingly, Ca2+-doped MgFe2O4 NPs exhibited superior cytotoxicity to laser-irradiated MDA-MB-231 cells, inducing significant cell death. Our study proposes novel, safe, high-efficiency, and biocompatible PT therapeutics for treating cancers, opening new vistas for the future development of cancer PTT.

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