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1.
Microb Cell Fact ; 23(1): 259, 2024 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-39343880

RESUMO

BACKGROUND: Antimicrobial resistance has emerged as a major global health threat, necessitating the urgent development of new antimicrobials through innovative methods to combat the rising prevalence of resistant microbes. With this view, we developed three novel nanoconjugates using microbial natural pigment for effective application against certain pathogenic microbes. RESULTS: A natural red pigment (RP) extracted from the endophyte Monascus ruber and gamma rays were applied to synthesize RP-ZnO, RP-CuO, and RP-MgO nanoconjugates. The synthesized nanoconjugates were characterized by different techniques to study their properties. The antimicrobial potential of these nanoconjugates was evaluated. Moreover, the antibiofilm, protein leakage, growth curve, and UV light irradiation effect of the synthesized nanoconjugates were also studied. Our results confirmed the nano-size, shape, and stability of the prepared conjugates. RP-ZnO, RP-CuO, and RP-MgO nanoconjugates showed broad antimicrobial potential against the tested bacterial and fungal pathogens. Furthermore, the RP-ZnO nanoconjugate possessed the highest activity, followed by the RP-CuO against the tested microbes. The highest % inhibition of biofilm formation by the RP-ZnO nanoconjugate. Membrane leakage of E. coli and S. aureus by RP-ZnO nanoconjugate was more effective than RP-MgO and RP-CuO nanoconjugates. Finally, UV light irradiation intensified the antibiotic action of the three nanoconjugates and RP-ZnO potential was greater than that of the RP-MgO, and RP-CuO nanoconjugates. CONCLUSION: These findings pave the way for exploiting the synthesized nanoconjugates as potential materials in biomedical applications, promoting natural, green, and eco-friendly approaches.


Assuntos
Monascus , Nanoconjugados , Monascus/metabolismo , Nanoconjugados/química , Biofilmes/efeitos dos fármacos , Pigmentos Biológicos/química , Fermentação , Cobre/química , Cobre/farmacologia , Endófitos/metabolismo , Endófitos/química , Óxido de Zinco/química , Óxido de Zinco/farmacologia , Testes de Sensibilidade Microbiana , Óxido de Magnésio/química , Óxido de Magnésio/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Escherichia coli/efeitos dos fármacos
2.
Nanotechnology ; 35(27)2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38502954

RESUMO

Developing sustainable and innovative approaches for the efficient reduction of nitrophenols is crucial for environmental remediation, for managing health concerns posed by their widespread presence as hazardous pollutants in industrial effluents and contaminated water. We report the use of 12.9 ± 1 nm (TEM data) sized gold carbon dot nanoconjugates (Au@CDs) for catalytic conversion of o, m, p-nitrophenols to aminophenols by sodium borohydride. A simple approach was followed to synthesize ultra-small and highly stable Au@CDs, using citric acid and PEG as reducing and stabilizing agents. X-ray diffraction analysis verified the formation of nano-crystalline nanoconjugates. These nanoconjugates showed a remarkable catalytic activity in the range of 0.22-0.33 s-1(varying with nanoconjugate concentration) which was much higher compared to conventional chemical methods of reduction. All the catalytic reaction experiments were performed at room temperature (27 ± 2 °C). Furthermore, an increase in rate constant was observed with increasing concentration of nanoconjugates. The catalytic activity of Au@CDs nanoconjugates was observed to be in order of m-nitrophenol > o-nitrophenol > p-nitrophenol with apparent rate constant (kaap) values of 0.068, 0.043 and 0.031, respectively. Comparative analysis with GNPs, CDs and Au@CDs nanoconjugates stated that the nanoconjugates had superior catalytic activity. The research can have significant implications in the development of new strategies for environmental remediation and biomedical applications.

3.
Bioorg Chem ; 151: 107629, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39003942

RESUMO

Melanin is a complex brown pigment, primarily responsible for the skin pigmentation. Therefore, cosmetic industries have always been in search of potent oxidative enzymes useful for melanin degradation, and to promise a fair complexion after using their products. In the present study, lignin peroxidase from Pseudomonas fluorescence LiP-RL5 isolate has been immobilized on super-paramagnetic nanoparticles to enhance its stability and reusability. The chitosan coated enzyme-nanomaterial complex (LiP@MFO-Chit) showed higher melanin decolorization (47.30 ± 2.3 %) compared to the graphene oxide coated nanoparticles (LiP@MFO-GO) (41.60 ± 1.6 %). Synthesized enzyme nanoparticle complexes showed microbicidal effect on skin infection causing pathogen, Pantoea agglomerans with an inhibitory zone of 6.0 ± 0.9 mm and 250 µg/100 µl minimum inhibitory concentration, and a 7.0 ± 1.5 mm zone and 170 µg/100 µl MIC for LiP@MFO-GO and LiP@MFO-Chit, respectively. Antioxidant potential of LiP@MFO-Chit and LiP@MFO-GO nano-conjugates showed a substantial DPPH scavenging activity of 75.7 % and 88.3 %, respectively. Therefore, LiP-nanoparticle hybrid complexes analyzed in this study are not only effective as skin whitening agents but they are potential molecules against various microbial skin infections as well as useful for different other biomedical applications like biorefinery, drug delivery, and dermatology, etc.


Assuntos
Quitosana , Grafite , Melaninas , Testes de Sensibilidade Microbiana , Melaninas/metabolismo , Melaninas/química , Quitosana/química , Quitosana/farmacologia , Grafite/química , Grafite/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Peroxidases/metabolismo , Peroxidases/química , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Pantoea , Antioxidantes/química , Antioxidantes/farmacologia , Antioxidantes/síntese química , Estrutura Molecular , Pseudomonas , Relação Dose-Resposta a Droga , Relação Estrutura-Atividade , Picratos/antagonistas & inibidores , Nanopartículas/química , Compostos de Bifenilo/antagonistas & inibidores , Compostos de Bifenilo/química
4.
World J Microbiol Biotechnol ; 40(9): 287, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39090427

RESUMO

Bacteriocins are antimicrobial peptides produced by bacteria to prevent the growth of pathogens. Combining bacteriocins with metal nanoparticles, like silver nanoparticles (AgNPs), has developed into a viable strategy to get over bacteriocin limitations. In this study, bacteriocin BacZY05 was extracted from Bacillus subtilis ZY05 and purified using various techniques. The resulting purified bacteriocin was then combined with silver nanoparticles to form bacteriocin silver nanoconjugates (BacZY05-AgNPs). The physicochemical properties of the BacZY05-AgNPs were characterized using various analytical techniques. The mean diameter of the synthesized AgNPs was approximately 20-60 nm with an oval or spherical shape. The antimicrobial activity of the BacZY05-AgNPs was evaluated against several indicator strains by their zone of inhibition (ZOI), using the agar well diffusion method. Compared to bacteriocin (ZOI- 13 to 20 mm) and AgNPs (ZOI- 10-22 mm) alone, the antibacterial activity data demonstrated a 1.3-1.5-fold increase in the activity of bacteriocin-nanoconjugates (ZOI- 22 to 26 mm). For Staphylococcus aureus MTCC3103 and Klebsiella pneumoniae MTCC109, BacZY05-capped AgNPs exhibited the lowest minimum inhibitory concentration (MIC), measuring 10.93 µg/mL. For Salmonella typhi NCIM2501, the MIC was 28.75 µg/mL. The highest MIC value was 57.5 µg/mL for Escherichia coli DH5α and Vibrio cholerae MTCC3909. With BacZY05-capped AgNPs, the lowest minimum bactericidal concentration (MBC) of 28.75 µg/mL was observed for Staphylococcus aureus MTCC31003. In the cases of Salmonella typhi NCIM2501 and Klebsiella pneumoniae MTCC109 concentration was 57.5 µg/mL. Vibrio cholerae MTCC3909 and Escherichia coli DH5α had the highest MBC values at 115 µg/mL.


Assuntos
Antibacterianos , Bacillus subtilis , Bacteriocinas , Klebsiella pneumoniae , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Nanoconjugados , Prata , Staphylococcus aureus , Antibacterianos/farmacologia , Antibacterianos/química , Prata/farmacologia , Prata/química , Bacteriocinas/farmacologia , Bacteriocinas/química , Bacteriocinas/biossíntese , Nanopartículas Metálicas/química , Staphylococcus aureus/efeitos dos fármacos , Nanoconjugados/química , Bacillus subtilis/efeitos dos fármacos , Klebsiella pneumoniae/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos
5.
Biochem Biophys Res Commun ; 655: 97-103, 2023 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-36934590

RESUMO

Serum cholesterol dysregulation is associated with prognosis and diagnosis of many diseases and effective biosensor will improvise their management. A novel electrochemical biosensor was fabricated based on gelatin-Au@CD nanoconjugate films for cholesterol detection. Initially, the surface of indium titanium oxide (ITO) coated glass was modified by drop casting of gelatin-Au@CD nanoconjugates to prepare the electrodes. Electrochemical studies for detection of bioanalytes(such as urea (U), ascorbic acid (AA), oxalic acid (OA), gallic acid (GA), cholesterol (Chox), dextrose (D), l-cysteine (Cys) and citric acid (CA)) were performed using cyclic voltammetry. The presence of nanoconjugates provided an appropriate environment for enhanced electrochemical response for cholesterol. These electrodes exhibited a linear response towards the presence of cholesterol in the linear concentration range of 2-20 mM with a correlation coefficient of 0.95, and the superior sensitivity of 1.36 µA/mM/cm2. Additionally, enhanced sensitivity (2.99 µA/mM/cm2) of nitrogen ion irradiated films up to a fluence of 1016 ions/cm2 was noticed because of morphological changes in the electrode surface brought about by irradiation. Approximately 54% enhancement was found when the ion fluence was 1016 ions/cm2. The designed nanoconjugate electrode showed excellent response towards cholesterol sensing and eliminates the requirement of any enzymes making the overall process simpler, cost-effective and allows for room temperature storage.


Assuntos
Técnicas Biossensoriais , Carbono , Nanoconjugados , Gelatina , Ouro , Colesterol , Eletrodos , Técnicas Eletroquímicas
6.
Chem Biodivers ; 20(7): e202300389, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37366243

RESUMO

In this study, a new phthalonitrile derivative namely 4-[(2,4-difluorophenyl)ethynyl]phthalonitrile (1) and its metal phthalocyanines (2 and 3) were synthesized. The resultant compounds were conjugated to silver nanoparticles and characterized using transmission electron microscopy (TEM) images. The biological properties of compounds (1-3), their nanoconjugates (4-6), and silver nanoparticles (7) were examined for the first time in this study. The antioxidant activities of biological candidates (1-7) were studied by applying the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. The highest antioxidant activity was obtained 97.47 % for 200 mg/L manganese phthalocyanine-silver nanoconjugates (6). The antimicrobial and antimicrobial photodynamic therapy (APDT) activities of biological candidates (1-7) were examined using a micro-dilution assay. The highest MIC value was obtained 8 mg/L for nanoconjugate 6 against E. hirae. The studied compounds and their silver nanoconjugates exhibited high APDT activities against all the studied microorganisms. The most effective APDT activities were obtained 4 mg/L for nanoconjugates (5 and 6) against L. pneumophila and E. hirae, respectively. All the studied biological candidates displayed high cell viability inhibition activities against E. coli cell growth. The biofilm inhibition activities of the tested biological candidates were also investigated against S. aureus and P. Aeruginosa. Biological candidates (1-6) can be considered efficient metal nanoparticle-based materials for multi-disciplinary biological applications.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Nanoconjugados/química , Prata/farmacologia , Prata/química , Nanopartículas Metálicas/química , Staphylococcus aureus , Escherichia coli , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Testes de Sensibilidade Microbiana
7.
J Appl Microbiol ; 131(3): 1056-1071, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33368869

RESUMO

Resistance to antibiotics is an ongoing problem in the biomedical industry. Developing active, alternative drug therapies would reduce our reliance on antibiotics that induce resistance in micro-organisms. To date, bacteriocins and antimicrobial peptides have shown a positive outcome as antibiotic substitutes and synergists apart from phage therapy, antibodies and probiotics. Bacteriocins are proteinaceous antimicrobial peptides synthesized by lactic acid bacteria extensively used as bio-preservatives and alternative to traditional antibiotics to overcome the problem of drug-resistant pathogens. Nonetheless, the use of bacteriocins has several limitations such as limited antimicrobial spectrum, requiring high dose, sensitivity to proteolytic enzymes, etc. Nanoparticles are one of the promising area of research explored to improve antimicrobial spectrum of bacteriocins. This review therefore highlights the recent developments and research pertaining to use of nanoparticles and bacteriocin conjugates to tackle the resistance crisis as well as its applications in food industry.


Assuntos
Bacteriocinas , Antibacterianos , Indústria Alimentícia , Nanoconjugados
8.
Proc Natl Acad Sci U S A ; 115(17): 4340-4344, 2018 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-29632214

RESUMO

Herein, we report a class of molecular spherical nucleic acid (SNA) nanostructures. These nano-sized single molecules are synthesized from T8 polyoctahedral silsesquioxane and buckminsterfullerene C60 scaffolds, modified with 8 and 12 pendant DNA strands, respectively. These conjugates have different DNA surface densities and thus exhibit different levels of nuclease resistance, cellular uptake, and gene regulation capabilities; the properties displayed by the C60 SNA conjugate are closer to those of conventional and prototypical gold nanoparticle SNAs. Importantly, the C60 SNA can serve as a single entity (no transfection agent required) antisense agent to efficiently regulate gene expression. The realization of molecularly pure forms of SNAs will open the door for studying the interactions of such structures with ligands and living cells with a much greater degree of control than the conventional polydisperse forms of SNAs.


Assuntos
Modelos Moleculares , Conformação de Ácido Nucleico , Poli T/química
9.
Int J Mol Sci ; 22(6)2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33806807

RESUMO

Self-aggregation of Curcumin (Cur) in aqueous biological environment decreases its bioavailability and in vivo therapeutic efficacy, which hampers its clinical use as candidate for reducing risk of neurodegenerative diseases. Here, we focused on the design of new Cur- ß-Cyclodextrin nanoconjugates to improve the solubility and reduce cell toxicity of Cur. In this study, we described the synthesis, structural characterization, photophysical properties and neuron cell toxicity of two new water soluble ß-CD/Cur nanoconjugates as new strategy for reducing risks of neurodegenerative diseases. Cur was coupled to one or two ß-CD molecules via triazole rings using CuAAC click chemistry strategy to yield ß-CD@Cur and (ß-CD)2@Cur nanoconjugates, respectively. The synthesized nanoconjugates were found to be able to self-assemble in aqueous condition and form nano-aggregates of an average diameter size of around 35 and 120 nm for ß-CD@Cur and (ß-CD)2@Cur, respectively. The photophysical properties, water solubility and cell toxicity on rat embryonic cortical neurons of the designed nanoconjugates were investigated and compared to that of Cur alone. The findings revealed that both new nanoconjugates displayed better water solubility and in vitro biocompatibility than Cur alone, thus making it possible to envisage their use as future nano-systems for the prevention or risk reduction of neurodegenerative diseases.


Assuntos
Técnicas de Química Sintética , Curcumina/química , Curcumina/farmacologia , Nanoconjugados/química , beta-Ciclodextrinas/química , Animais , Disponibilidade Biológica , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Curcumina/síntese química , Liberação Controlada de Fármacos , Estrutura Molecular , Nanoconjugados/ultraestrutura , Neurônios/efeitos dos fármacos , Tamanho da Partícula , Ratos , Solubilidade
10.
Int J Mol Sci ; 22(17)2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34502173

RESUMO

The development in the area of novel anticancer prodrugs (conjugates and complexes) has attracted growing attention from many research groups. The dangerous side effects of currently used anticancer drugs, including cisplatin and other platinum based drugs, as well their systemic toxicity is a driving force for intensive search and presents a safer way in delivery platform of active molecules. Silicon based nanocarriers play an important role in achieving the goal of synthesis of the more effective prodrugs. It is worth to underline that silicon based platform including silica and silsesquioxane nanocarriers offers higher stability, biocompatibility of such the materials and pro-longed release of active platinum drugs. Silicon nanomaterials themselves are well-known for improving drug delivery, being themselves non-toxic, and versatile, and tailored surface chemistry. This review summarizes the current state-of-the-art within constructs of silicon-containing nano-carriers conjugated and complexed with platinum based drugs. Contrary to a number of other reviews, it stresses the role of nano-chemistry as a primary tool in the development of novel prodrugs.


Assuntos
Antineoplásicos/química , Portadores de Fármacos/química , Compostos Organoplatínicos/química , Silício/química , Nanomedicina Teranóstica , Animais , Antineoplásicos/farmacologia , Cisplatino/química , Cisplatino/farmacologia , Sistemas de Liberação de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Humanos , Estrutura Molecular , Compostos Organoplatínicos/farmacologia , Dióxido de Silício/química , Relação Estrutura-Atividade , Nanomedicina Teranóstica/métodos
11.
Int J Mol Sci ; 22(18)2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34576088

RESUMO

Nanosilver with sizes 1-100 nm at least in one dimension is widely used due to physicochemical, anti-inflammatory, anti-angiogenesis, antiplatelet, antifungal, anticancer, antibacterial, and antiviral properties. Three modes of the nanosilver action were suggested: "Trojan horse", inductive, and quantum mechanical. The Ag+ cations have an affinity to thiol, amino, phosphate, and carboxyl groups. Multiple mechanisms of action towards proteins, DNA, and membranes reduce a risk of pathogen resistance but inevitably cause toxicity for cells and organisms. Silver nanoparticles (AgNP) are known to generate two reactive oxygen species (ROS)-superoxide (•O2-) and hydroxyl (•OH) radicals, which inhibit the cellular antioxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase) and cause mechanical damage of membranes. Ag+ release and replacement by electrolyte ions with potential formation of insoluble AgCl result in NP instability and interactions of heavy metals with nucleic acids and proteins. Protein shells protect AgNP core from oxidation, dissolution, and aggregation, and provide specific interactions with ligands. These nanoconjugates can be used for immunoassays and diagnostics, but the sensitivity is limited at 10 pg and specificity is restricted by binding with protective proteins (immunoglobulins, fibrinogen, albumin, and others). Thus, broad implementation of Ag nanostructures revealed limitations such as instability; binding with major blood proteins; damage of proteins, nucleic acids, and membranes; and immunosuppression of the majority of cytokines.


Assuntos
Anti-Inflamatórios/farmacologia , Limite de Detecção , Nanopartículas Metálicas/toxicidade , Prata/toxicidade , Testes de Toxicidade , Animais , Citoproteção/efeitos dos fármacos , Humanos
12.
Molecules ; 27(1)2021 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-35011342

RESUMO

Green synthesis of silver nanoparticles (AgNPs) was synthesized from fresh garlic extract coupled with isoniazid hydrazide (INH), a commonly used antibiotic to treat tuberculosis. A molecular docking study conducted with the selected compounds compared with anthranilate phosphoribosyltransferase (trpD) from Mycobacterium tuberculosis. The aqueous extract of garlic was prepared and mixed with silver nitrate (AgNO3) solution for the superfast synthesis of stable AgNPs. INH was then conjugated with AgNPs at different ratios (v/v) to obtain stable INH-AgNPs conjugates (AgNCs). The resulting AgNCs characterized by FTIR spectra revealed the ultrafast formation of AgNPs (<5 s) and perfectly conjugated with INH. The shifting of λmax to longer wavelength, as found from UV spectral analysis, confirmed the formation of AgNCs, among which ideal formulations (F7, F10, and F13) have been pre-selected. The zeta particle size (PS) and the zeta potential (ZP) of AgNPs were found to be 145.3 ± 2.1 nm and -33.1 mV, respectively. These data were significantly different compared to that of AgNCs (160 ± 2.7 nm and -14.4 mV for F7; 208.9 ± 2.9 nm and -19.8 mV for F10; and 281.3 ± 3.6 nm and -19.5 mV for F13), most probably due to INH conjugation. The results of XRD, SEM and EDX confirmed the formation of AgNCs. From UV spectral analysis, EE of INH as 51.6 ± 5.21, 53.6 ± 6.88, and 70.01 ± 7.11 %, for F7, F10, and F13, respectively. The stability of the three formulations was confirmed in various physiological conditions. Drug was released in a sustainable fashion. Besides, from the preferred 23 compounds, five compounds namely Sativoside R2, Degalactotigonin, Proto-desgalactotigonin, Eruboside B and Sativoside R1 showed a better docking score than trpD, and therefore may help in promoting anti-tubercular activity.


Assuntos
Alho/química , Hidrazinas/química , Isoniazida/síntese química , Isoniazida/farmacologia , Nanopartículas Metálicas/química , Extratos Vegetais/química , Prata/química , Antituberculosos/química , Antituberculosos/farmacologia , Sítios de Ligação , Técnicas de Química Sintética , Estabilidade de Medicamentos , Química Verde , Isoniazida/química , Ligantes , Nanopartículas Metálicas/ultraestrutura , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Ligação Proteica , Análise Espectral , Relação Estrutura-Atividade
13.
Biomed Microdevices ; 22(2): 28, 2020 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-32222830

RESUMO

Early detection and treatment of cardiovascular disease by identifying markers is important to improve the health of our citizens and simultaneously reduce the cost of health care. Therefore, there is an urgent need for early detection and treatment of asymptomatic cardiovascular disease. Herein, we have developed highly sensitive vertical flow immunokit (VFIK) for the detection of C-reactive protein (CRP), comprising an antibody/citrate conjugated gold nanoparticle in a fixed orientation surface. Our CRP test kit has been optimized with various parameters such as buffer composition, the quantity of captured antibody and sensitivity of the assay. Prominently, our developed CRP test kit is highly sensitive and rapid point of care test (POCT) which is capable to detect CRP with minimal volume (50-60 µl) and time (1-2 min) with diminutive detection up to 10 ng/ml. The reliability of our kit was evaluated and validated with spiked and clinical whole blood samples. The results demonstrated that our developed vertical flow-based point-of-care Immunokit may serve fruitful and semi-quantitative routine diagnostic for the early detection of cardiac disease.


Assuntos
Proteína C-Reativa/metabolismo , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/metabolismo , Imunoensaio/instrumentação , Sistemas Automatizados de Assistência Junto ao Leito , Diagnóstico Precoce , Humanos , Fatores de Risco , Sensibilidade e Especificidade , Fatores de Tempo
14.
Bioorg Chem ; 96: 103617, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32014639

RESUMO

Anthracyclines (Anth) are widely used in the treatment of various types of cancer. Unfortunately, they exhibit serious adverse effects, such as hematopoietic depression and cardiotoxicity, leading to heart failure. In this review, we focus on recently developed conjugates of anthracyclines with a range of nanocarriers, such as polymers, peptides, DNA or inorganic systems. Manipulation of the composition, size and shape of chemical entities at the nanometer scale makes possible the design and development of a range of prodrugs. In this review we concentrate on synthetic chemistry in the long process leading to the introduction of novel therapeutic products.


Assuntos
Antraciclinas/química , Antineoplásicos/química , Nanoconjugados/química , Antraciclinas/síntese química , Antineoplásicos/síntese química , Técnicas de Química Sintética/métodos , Desenho de Fármacos , Humanos , Nanotecnologia/métodos , Neoplasias/tratamento farmacológico , Pró-Fármacos/síntese química , Pró-Fármacos/química
15.
Proc Natl Acad Sci U S A ; 114(16): 4129-4134, 2017 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-28373576

RESUMO

RNA interference (RNAi)-based gene regulation platforms have shown promise as a novel class of therapeutics for the precision treatment of cancer. Techniques in preclinical evaluation of RNAi-based nanoconjugates have yet to allow for optimization of their gene regulatory activity. We have developed spherical nucleic acids (SNAs) as a blood-brain barrier-/blood-tumor barrier-penetrating nanoconjugate to deliver small interfering (si) and micro (mi)RNAs to intracranial glioblastoma (GBM) tumor sites. To identify high-activity SNA conjugates and to determine optimal SNA treatment regimens, we developed a reporter xenograft model to evaluate SNA efficacy in vivo. Engrafted tumors stably coexpress optical reporters for luciferase and a near-infrared (NIR) fluorescent protein (iRFP670), with the latter fused to the DNA repair protein O6-methylguanine-DNA-methyltransferase (MGMT). Using noninvasive imaging of animal subjects bearing reporter-modified intracranial xenografts, we quantitatively assessed MGMT knockdown by SNAs composed of MGMT-targeting siRNA duplexes (siMGMT-SNAs). We show that systemic administration of siMGMT-SNAs via single tail vein injection is capable of robust intratumoral MGMT protein knockdown in vivo, with persistent and SNA dose-dependent MGMT silencing confirmed by Western blotting of tumor tissue ex vivo. Analyses of SNA biodistribution and pharmacokinetics revealed rapid intratumoral uptake and significant intratumoral retention that increased the antitumor activity of coadministered temozolomide (TMZ). Our study demonstrates that dual noninvasive bioluminescence and NIR fluorescence imaging of cancer xenograft models represents a powerful in vivo strategy to identify RNAi-based nanotherapeutics with potent gene silencing activity and will inform additional preclinical and clinical investigations of these constructs.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Metilases de Modificação do DNA/antagonistas & inibidores , Enzimas Reparadoras do DNA/antagonistas & inibidores , Glioblastoma/tratamento farmacológico , Nanoconjugados/administração & dosagem , RNA Interferente Pequeno/genética , Proteínas Supressoras de Tumor/antagonistas & inibidores , Animais , Antineoplásicos Alquilantes/farmacologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Dacarbazina/análogos & derivados , Dacarbazina/farmacologia , Feminino , Fluorescência , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Camundongos , Camundongos SCID , Nanoconjugados/química , Interferência de RNA , Temozolomida , Células Tumorais Cultivadas , Proteínas Supressoras de Tumor/genética , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Mater Lett ; 277: 128279, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32834256

RESUMO

The earliest possible diagnosis and understanding of the infection mechanisms play a crucial role in the outcome of fighting viral diseases. Thus, we designed and developed for the first time, novel bioconjugates made of Ag-In-S@ZnS (ZAIS) fluorescent quantum dots coupled with ZIKA virus via covalent amide bond with carboxymethylcellulose (CMC) biopolymer for labeling and bioimaging the virus-host cell interactions mechanisms through confocal laser scanning microscopy. This work offers relevant insights regarding the profile of the ZIKA virus-nanoparticle conjugates interactions with VERO cells, which can be applied as a nanoplatform to elucidate the infection mechanisms caused by this viral disease.

17.
Angew Chem Int Ed Engl ; 59(5): 2018-2022, 2020 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-31746532

RESUMO

Exosomes hold great potential in therapeutic development. However, native exosomes usually induce insufficient effects in vivo and simply act as drug delivery vehicles. Herein, we synthesize responsive exosome nano-bioconjugates for cancer therapy. Azide-modified exosomes derived from M1 macrophages are conjugated with dibenzocyclooctyne-modified antibodies of CD47 and SIRPα (aCD47 and aSIRPα) through pH-sensitive linkers. After systemic administration, the nano-bioconjugates can actively target tumors through the specific recognition between aCD47 and CD47 on the tumor cell surface. In the acidic tumor microenvironment, the benzoic-imine bonds of the nano-bioconjugates are cleaved to release aSIRPα and aCD47 that can, respectively, block SIRPα on macrophages and CD47, leading to abolished "don't eat me" signaling and improved phagocytosis of macrophages. Meanwhile, the native M1 exosomes effectively reprogram the macrophages from pro-tumoral M2 to anti-tumoral M1.


Assuntos
Exossomos/metabolismo , Imunoterapia/métodos , Nanotecnologia/métodos , Neoplasias/terapia , Humanos , Neoplasias/patologia
18.
Mol Pharm ; 15(7): 2559-2569, 2018 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-29764120

RESUMO

Photodynamic therapy, a procedure that uses a photosensitizer to enable light therapy selectively at diseased sites, remains underutilized in oncological clinic. To further improve its cancer selectivity, we developed a polymeric nanosystem by conjugating a photosensitizer IRDye 700DX (IR700) and cancer targeting RGD peptide to 8-arm polyethylene glycol (PEG). The resulting nanoconjugates (RGD-8PEG-IR700) exhibited a hydrodynamic size of 6.6 nm with narrow distribution of size. The targeted nanoconjugates showed significantly higher intracellular uptake of IR700 in integrin αvß3-expressing A375 and SKOV3 cells when compared with nontargeted control 8PEG-IR700, and an excess amount of RGD peptides could abolish this enhancement, indicating a receptor-mediated uptake mechanism for the targeted polymer conjugates. Phototoxicity studies indicated that RGD-8PEG-IR700 produced massive cell killing in A375 cells after photoirradiation with an IC50 value of 57.8 nM for IR700. In contrast, free IR700 and the control 8PEG-IR700 conjugates did not produce any phototoxicity at the concentrations up to 1 µM IR700. Upon photoirradiation, the RGD-8PEG-IR700 could produce sufficient singlet oxygen in the cells and induced cell apoptosis. The studies with three-dimensional tumor spheroids showed that they penetrated tumor spheroids deeply and produced strong phototoxicity. Thus, we conclude that the polymer nanoconjugates may provide a promising delivery system for targeted photodynamic therapy of cancers due to their small size, cancer cell specificity, and minimal side effects.


Assuntos
Nanoconjugados/química , Neoplasias/tratamento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/administração & dosagem , Células 3T3 , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Concentração Inibidora 50 , Camundongos , Neoplasias/patologia , Oligopeptídeos/administração & dosagem , Polietilenoglicóis/química , Esferoides Celulares
19.
Int J Mol Sci ; 19(6)2018 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-29799469

RESUMO

Waterways are popular locations for the disposition of criminal evidence because the recovery of latent fingerprints from such evidence is difficult. Currently, small particle reagent is a method often used to visualize latent fingerprints containing carcinogenic and hazardous compounds. This study proposes an eco-friendly, safranin-tinted Candida rugosa lipase (triacylglycerol ester hydrolysis EC 3.1.1.3) with functionalized carbon nanotubes (CRL-MWCNTS/GA/SAF) as an alternative reagent to the small particle reagent. The CRL-MWCNTS/GA/SAF reagent was compared with the small particle reagent to visualize groomed, full fingerprints deposited on stainless steel knives which were immersed in a natural outdoor pond for 30 days. The quality of visualized fingerprints using the new reagent was similar (modified-Centre for Applied Science and Technology grade: 4; p > 0.05) to small particle reagent, even after 15 days of immersion. Despite the slight decrease in quality of visualized fingerprints using the CRL-MWCNTS/GA/SAF on the last three immersion periods, the fingerprints remained forensically identifiable (modified-Centre for Applied Science and Technology grade: 3). The possible chemical interactions that enabled successful visualization is also discussed. Thus, this novel reagent may provide a relatively greener alternative for the visualization of latent fingerprints on immersed non-porous objects.


Assuntos
Dermatoglifia , Ciências Forenses/métodos , Proteínas Fúngicas/química , Lipase/química , Nanoconjugados/química , Fenazinas/química , Candida/química , Candida/enzimologia , Água Doce , Glutaral/química , Química Verde , Humanos , Indicadores e Reagentes , Nanotubos de Carbono/química , Aço Inoxidável
20.
Mol Pharm ; 14(8): 2793-2804, 2017 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-28700237

RESUMO

Advances in photodynamic therapy of cancer have been restrained by lack of cancer specificity and side effects to normal tissues. Molecularly targeted photodynamic therapy can achieve higher cancer specificity by combination of active cancer targeting and localized laser activation. We aimed to use albumin as a carrier to prepare targeted nanoconjugates that are selective to cancer cells and smaller than conventional nanoparticles for superior tumor penetration. IRDye 700DX (IR700), a porphyrin photosensitizer, was covalently conjugated to human serum albumin that was also linked with tumor-targeting RGD peptides. With multiple IR700 and RGD molecules in a single albumin molecule, the resultant nanoconjugates demonstrated monodispersed and uniform size distribution with a diameter of 10.9 nm. These targeted nanoconjugates showed 121-fold increase in cellular delivery of IR700 into TOV21G ovarian cancer cells compared to control nanoconjugates. Mechanistic studies revealed that the integrin specific cellular delivery was achieved through dynamin-mediated caveolae-dependent endocytosis pathways. They produced massive cell killing in TOV21G cells at low nanomolar concentrations upon light irradiation, while NIH/3T3 cells that do not express integrin αvß3 were not affected. Because of their small size, targeted albumin nanoconjugates could penetrate tumor spheroids of SKOV-3 ovarian cancer cells and produced strong phototoxicity in this 3-D model. Owing to their cancer-specific delivery and small size, these targeted nanoconjugates may become an effective drug delivery system for enabling molecularly targeted photodynamic therapy of cancer.


Assuntos
Albuminas/química , Nanoconjugados/química , Nanopartículas/química , Fármacos Fotossensibilizantes/química , Fotoquimioterapia
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