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1.
Int J Biol Macromol ; 268(Pt 1): 131644, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38642691

RESUMO

Diabetes is a chronic metabolic disorder. Diabetes complications can affect many organs and systems in the body. Ganoderma lucidum (G. lucidum) contains various compounds that have been studied for their potential antidiabetic effects, including polysaccharides, triterpenoids (ganoderic acids, ganoderol B), proteoglycans, and G. lucidum extracts. G. lucidum polysaccharides (GLPs) and triterpenoids have been shown to act through distinct mechanisms, such as improving glucose metabolism, modulating the mitogen-activated protein kinase (MAPK) system, inhibiting the nuclear factor-kappa B (NF-κB) pathway, and protecting the pancreatic beta cells. While GLPs exhibit a significant role in controlling diabetic nephropathy and other associated complications. This review states the G. lucidum antidiabetic mechanisms of action and potential biologically active compounds that contribute to diabetes management and associated complications. To make G. lucidum an appropriate replacement for the treatment of diabetes with fewer side effects, more study is required to completely comprehend the number of physiologically active compounds present in it as well as the underlying cellular mechanisms that influence their effects on diabetes.

2.
BMC Chem ; 18(1): 23, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38287347

RESUMO

Heavy metals like Cadmium, Lead, and Chromium are the pollutants emitted into the environment through industrial development. In this work, a new diphenylamine coordinated cobalt complex (Co-DPA) has been synthesized and tested for its efficiency in removing heavy metals from wastewater, and its adsorption capacity was investigated. The effectiveness of heavy metals removal by Co-DPA was evaluated by adjusting the adsorption parameters, such as adsorbent dose, pH, initial metals concentration, and adsorption period. Heavy metal concentrations in real sample were 0.267, 0.075, and 0.125 mg/L for Cd2+, Pb2+, and Cr3+ before using as-synthesized Co-DPA to treat wastewater. After being treated with synthesized Co-DPA the concentration of heavy metals was reduced to 0.0129, 0.00028, 0.00054 mg/L for Cd2+, Pb2+, and Cr3+, respectively, in 80 min. The removal efficiency was 95.6%, 99.5%, and 99.5% for the respective metals. The adsorption process fitted satisfactorily with Freundlich isotherm with R2(0.999, 0.997, 0.995) for Cd2+, Pb2+, and Cr3+, respectively. The kinetic data obeyed the pseudo-second order for Cd2+ and Cr2+ and the pseudo-first order for Pb2+. Based on the results obtained within the framework of this study, it is concluded that the as-synthesized Co-DPA is a good adsorbent to eliminate heavy metal ions like Cd2+, Pb2+, and Cr3+from wastewater solution. In general, Co-DPA is a promising new material for the removal of heavy metal ions from water.

3.
ACS Omega ; 8(45): 42699-42710, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38024745

RESUMO

Herein, we have shown the interaction of an antibiotic drug ciprofloxacin (CIP) with three surface-active ionic liquids (ILs), having the same cation and different anions, namely, 1-decyl-3-methylimidazoliumtetrafluoroborate [C10mim][BF4], 1-decyl-3-methylimidazolium bromide [C10mim][Br], and 1-decyl-3-methylimidazolium chloride [C10mim][Cl]. This study has been performed by exploiting various spectroscopic techniques such as steady-state fluorescence, time-resolved fluorescence, and UV-visible spectroscopy. The fluorescence emission study of CIP with ILs was performed at various concentrations of all the three ILs. The emission spectra of CIP decreased in the presence of ILs, suggesting complex formation between CIP-IL. The effect of different concentrations of ILs on the emission spectra of CIP was exploited in terms of quenching and binding parameters. Further, fluorescence emission study was validated by the time-resolved fluorescence technique by measuring the average lifetime (τavg) of CIP in the presence of all the three ILs. The τavg value of the drug changed with the addition of ILs, which suggests complex formation between the drug and ILs. This complex formation was also confirmed by UV-visible spectroscopy results of CIP with all the three ILs. Further, for evaluating the thermodynamic parameters of the CIP-IL interactions, isothermal titration calorimetry (ITC) was performed. The ITC experiment yielded the thermodynamic parameters, ΔH (change in the enthalpy of association), ΔG (Gibbs free energy change), ΔS (entropy change), and binding constant (Ka). The binding parameters driven by ITC revealed that CIP-IL interactions are spontaneous in nature and enthalpy-driven, involving hydrophobic forces. Further, the classical density functional theory (DFT) calculations were performed, which provided deep insight for CIP-IL complex formation.

4.
ACS Omega ; 8(21): 18901-18914, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37273622

RESUMO

Silver nanoparticles (Ag-NPs) exhibit vast potential in numerous applications, such as wastewater treatment and catalysis. In this study, we report the green synthesis of Ag-NPs using Acacia ehrenbergiana plant cortex extract to reduce cationic Rhodamine B (RhB) dye and for antibacterial and antifungal applications. The green synthesis of Ag-NPs involves three main phases: activation, growth, and termination. The shape and morphologies of the prepared Ag-NPs were studied through different analytical techniques. The results confirmed the successful preparation of Ag-NPs with a particle size distribution ranging from 1 to 40 nm. The Ag-NPs were used as a heterogeneous catalyst to reduce RhB dye from aqueous solutions in the presence of sodium borohydride (NaBH4). The results showed that 96% of catalytic reduction can be accomplished within 32 min using 20 µL of 0.05% Ag-NPs aqueous suspension in 100 µL of 1 mM RhB solution, 2 mL of deionized water, and 1 mL of 10 mM NaBH4 solution. The results followed a zero-order chemical kinetic (R2 = 0.98) with reaction rate constant k as 0.059 mol L-1 s-1. Furthermore, the Ag-NPs were used as antibacterial and antifungal agents against 16 Gram-positive and Gram-negative bacteria as well as 1 fungus. The green synthesis of Ag-NPs is environmentally friendly and inexpensive, as well as yields highly stabilized nanoparticles by phytochemicals. The substantial results of catalytic reductions and antimicrobial activity reflect the novelty of the prepared Ag-NPs. These nanoparticles entrench the dye and effectively remove the microorganisms from polluted water.

5.
RSC Adv ; 13(25): 17297-17314, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37304772

RESUMO

MALDI-TOF MS has decades of experience in the detection and identification of microbial pathogens. This has now become a valuable analytical tool when it comes to the identification and detection of clinical microbial pathogens. This review gives a brief synopsis of what has been achieved using MALDI-TOF MS in clinical microbiology. The major focus, however, is on summarizing and highlighting the effectiveness of MALDI-TOF MS as a novel tool for rapid identification of food crop microbial pathogens. The methods used and the sample preparation methodologies reported thus far have been highlighted and the challenges and gaps and recommendations for fine tuning the technique have been put forth. In an era where anything close to the health and welfare of humanity has been considered as the top priority, this review pitches on one such relevant research topics.

6.
Materials (Basel) ; 16(10)2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37241385

RESUMO

Hydrogen is considered a good clean and renewable energy substitute for fossil fuels. The major obstacle facing hydrogen energy is its efficacy in meeting its commercial-scale demand. One of the most promising pathways for efficient hydrogen production is through water-splitting electrolysis. This requires the development of active, stable, and low-cost catalysts or electrocatalysts to achieve optimized electrocatalytic hydrogen production from water splitting. The objective of this review is to survey the activity, stability, and efficiency of various electrocatalysts involved in water splitting. The status quo of noble-metal- and non-noble-metal-based nano-electrocatalysts has been specifically discussed. Various composites and nanocomposite electrocatalysts that have significantly impacted electrocatalytic HERs have been discussed. New strategies and insights in exploring nanocomposite-based electrocatalysts and utilizing other new age nanomaterial options that will profoundly enhance the electrocatalytic activity and stability of HERs have been highlighted. Recommendations on future directions and deliberations for extrapolating information have been projected.

7.
Nanomaterials (Basel) ; 12(17)2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36080023

RESUMO

Due to the growing demand for hydrogen, the photocatalytic hydrogen production from alcohols present an intriguing prospect as a potential source of low-cost renewable energy. The noble metals (Ag, Au, Pd and Pt) deposited LaMnO3 nanocomposites were synthesized by a non-conventional green bio-reduction method using aqueous lemon peel extract, which acts as both reducing and capping agent. The successful deposition of the noble metals on the surface of LaMnO3 was verified by using powder XRD, FTIR, TEM, N2-physisorption, DR UV-vis spectroscopy, and XPS techniques. The photocatalytic activity of the synthesized nanocomposites was tested for photocatalytic H2 production under visible light irradiation. Different photocatalytic reaction parameters such as reaction time, pH, catalyst mass and reaction temperature were investigated to optimize the reaction conditions for synthesized nanocomposites. Among the synthesized noble metal deposited LaMnO3 nanocomposites, the Pt-LaMnO3 nanocomposite offered superior activity for H2 production. The enhanced photocatalytic activity of the Pt-LaMnO3 was found as a result from low bandgap energy, high photoelectrons generation and enhanced charge separation due to deposition of Pt nanoparticles. The effective noble metal deposition delivers a new route for the development of plasmonic noble metal-LaMnO3 nanocomposites for photocatalytic reforming of aqueous methanol to hydrogen.

8.
Polymers (Basel) ; 14(11)2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35683804

RESUMO

Chitosan has come a long way in biomedical applications: drug delivery is one of its core areas of imminent application. Chitosan derivatives are the new generation variants of chitosan. These modified chitosans have overcome limitations and progressed in the area of drug delivery. This review briefly surveys the current chitosan derivatives available for biomedical applications. The biomedical applications of chitosan derivatives are revisited and their key inputs for oral drug delivery have been discussed. The limited use of the vast chitosan resources for oral drug delivery applications, speculated to be probably due to the interdisciplinary nature of this research, is pointed out in the discussion. Chitosan-derivative synthesis and practical implementation for oral drug delivery require distinct expertise from chemists and pharmacists. The lack of enthusiasm could be related to the inadequacy in the smooth transfer of the synthesized derivatives to the actual implementers. With thiolated chitosan derivatives predominating the oral delivery of drugs, the need for representation from the vast array of ready-to-use chitosan derivatives is emphasized. There is plenty to explore in this direction.

9.
Polymers (Basel) ; 14(8)2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35458335

RESUMO

Chitosan and its allies have in multiple ways expanded into the medical, food, chemical, and biological industries and is still expanding. With its humble beginnings from marine shell wastes, the deacetylated form of chitin has come a long way in clinical practices. The biomedical applications of chitosan are truly a feather on its cap, with rarer aspects being chitosan's role in tissue regeneration and artificial organs. Tissue regeneration is a highly advanced and sensitive biomedical application, and the very fact that chitosan is premiering here is an authentication of its ability to deliver. In this review, the various biomedical applications of chitosan are touched on briefly. The synthesis methodologies that are specific for tissue engineering and biomedical applications have been listed. What has been achieved using chitosan and chitosan composites in artificial organ research as well as tissue regeneration has been surveyed and presented. The lack of enthusiasm, as demonstrated by the very few reports online with respect to chitosan composites and artificial organs, is highlighted, and the reasons for this lapse speculated. What more needs be done to expand chitosan and its allies for a better utilization and exploitation to best benefit the construction of artificial organs and building of tissue analogs has been discussed.

10.
Biology (Basel) ; 10(11)2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34827068

RESUMO

The facile bio-fabrication of zinc oxide (ZnO) nanoparticles (NPs) is described in this study using an aqueous leaf extract of Salvia officinalis L. as an efficient stabilizing/capping agent. Biosynthesis of nanomaterials using phytochemicals present in the plants has received great attention and is gaining significant importance as a possible alternative to the conventional chemical methods. The properties of the bio-fabricated ZnONPs were examined by different techniques, such as UV-visible spectroscopy, X-ray diffraction spectroscopy (XRD), energy-dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and thermogravimetric/differential scanning calorimetry analysis (TGA/DTG). The photocatalytic activity of ZnONPs was investigated against methyl orange (MO) under UV light irradiation. Under optimum experimental conditions, ZnONPs exhibited 92.47% degradation of MO. Furthermore, the antifungal activity of bio-fabricated ZnONPs was determined against different clinical Candida albicans isolates following standard protocols of broth microdilution and disc diffusion assay. The susceptibility assay revealed that ZnONPs inhibit the growth of all the tested fungal isolates at varying levels with MIC values ranging from 7.81 to 1.95 µg/mL. Insight mechanisms of antifungal action appeared to be originated via inhibition of ergosterol biosynthesis and the disruption of membrane integrity. Thus, it was postulated that bio-fabricated ZnONPs have sustainable applications in developing novel antifungal agents with multiple drug targets. In addition, ZnONPs show efficient photocatalytic efficiency without any significant catalytic loss after the catalyst was recycled and reused multiple times.

11.
Nanomaterials (Basel) ; 11(3)2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33806968

RESUMO

Chitin (poly-N-acetyl-D-glucosamine) is the second (after cellulose) most abundant organic polymer. In its deacetylated form-chitosan-becomes a very interesting material for medical use. The chitosan nano-structures whose preparation is described in this article shows unique biomedical value. The preparation of nanochitosan, as well as the most vital biomedical applications (antitumor, drug delivery and other medical uses), have been discussed in this review. The challenges confronting the progress of nanochitosan from benchtop to bedside clinical settings have been evaluated. The need for inclusion of nano aspects into chitosan research, with improvisation from nanotechnological inputs has been prescribed for breaking down the limitations. Future perspectives of nanochitosan and the challenges facing nanochitosan applications and the areas needing research focus have been highlighted.

12.
Antioxidants (Basel) ; 10(2)2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33546282

RESUMO

Chitosan is obtained from chitin that in turn is recovered from marine crustacean wastes. The recovery methods and their varying types and the advantages of the recovery methods are briefly discussed. The bioactive properties of chitosan, which emphasize the unequivocal deliverables contained by this biopolymer, have been concisely presented. The variations of chitosan and its derivatives and their unique properties are discussed. The antioxidant properties of chitosan have been presented and the need for more work targeted towards harnessing the antioxidant property of chitosan has been emphasized. Some portions of the crustacean waste are being converted to chitosan; the possibility that all of the waste can be used for harnessing this versatile multifaceted product chitosan is projected in this review. The future of chitosan recovery from marine crustacean wastes and the need to improve in this area of research, through the inclusion of nanotechnological inputs have been listed under future perspective.

13.
Int J Mol Sci ; 21(3)2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32024005

RESUMO

The clinical sampling of urine is noninvasive and unrestricted, whereby huge volumes can be easily obtained. This makes urine a valuable resource for the diagnoses of diseases. Urinary and renal proteomics have resulted in considerable progress in kidney-based disease diagnosis through biomarker discovery and treatment. This review summarizes the bioinformatics tools available for this area of proteomics and the milestones reached using these tools in clinical research. The scant research publications and the even more limited bioinformatic tool options available for urinary and renal proteomics are highlighted in this review. The need for more attention and input from bioinformaticians is highlighted, so that progressive achievements and releases can be made. With just a handful of existing tools for renal and urinary proteomic research available, this review identifies a gap worth targeting by protein chemists and bioinformaticians. The probable causes for the lack of enthusiasm in this area are also speculated upon in this review. This is the first review that consolidates the bioinformatics applications specifically for renal and urinary proteomics.


Assuntos
Biologia Computacional/métodos , Rim/metabolismo , Urina/química , Biomarcadores/urina , Humanos , Proteômica , Doenças Urológicas/diagnóstico , Doenças Urológicas/metabolismo , Doenças Urológicas/urina
14.
Sci Rep ; 9(1): 13832, 2019 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-31554844

RESUMO

Chitin and chitosan are biopolymers that have diverse applications in medicine, agriculture, food, cosmetics, pharmaceuticals, wastewater treatment and textiles. With bio-origins, they easily blend with biological systems and show exemplified compatibility which is mandatory when it comes to biomedical research. Chitin and chitosan are ecofriendly, however the processes that are used to recover them aren't ecofriendly. The focus of this work is to attempt an ecofriendly, sustainable phytomediated one pot recovery of chitosan from commercial chitin and from crab and shrimp shells and squid pen solid wastes. Graviola extracts have been employed, given the fact file that their active ingredients acetogenins actively interact with chitin in insects (resulting in its application as an insecticide). With that as the core idea, the graviola extracts were chosen for orchestrating chitin recovery and a possible chitin to chitosan transformation. The results confirm that graviola extracts did succeed in recovery of chitosan nanofibers from commercial chitin flakes and recovery of chitosan particles directly from solid marine wastes of crab, shrimp and squids. This is a first time report of a phyto-extract mediated novel chitosan synthesis method.

15.
J Photochem Photobiol B ; 183: 154-163, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29705508

RESUMO

Trigonella foenum-graecum is the source of various biological and chemical constituents with a wide area of applications, especially in the treatment/prevention of diabetes and other chronic diseases such as cancer. Multiple biological and organic moieties in the aqueous or the organic phase of Trigonella foenum-graecum carry soft reduction properties to reduce the metal cations to nanoparticles. In this investigation, the Trigonella foenum-graecum was found in the seed extract for the first time in an aqueous medium. We successfully synthesized zero-valent iron nanoparticles (Fe0) (ZV-Fe NPs) and stabilized these nanoparticles in an aqueous medium. The stabilization mechanism of Fe NPs by Trigonella foenum-graecum in an aqueous extract was investigated. Further, Fe NPs were characterized by UV-visible spectrometry, X-ray diffraction (XRD), thermogravimetric analysis - derivative thermo-gravimetric (TGA/DTG), magnetization, Fourier transform infrared (FTIR) spectroscopy and transmission electron microscopy (TEM) images. The size of the nanoparticles, calculated using the Debye-Scherer equation and TEM, was found to be approximately 11 nm with the highest particle distribution number. Fe NPs are very effective for methyl orange dye degradation under UV light following pseudo first-order kinetics, and the rate constant kapp was found to be 0.025 min-1. Furthermore, Fe NPs were applied to check the antibacterial activities with microorganisms such as gram-negative E. coli and gram-positive S. aureus. The Minimum Inhibitory Concentration (MIC) of Fe NPs for E. coli and S. aureus was calculated as 32 µg/mL and 64 µg/mL, respectively.


Assuntos
Antibacterianos/química , Ferro/química , Nanopartículas Metálicas/química , Extratos Vegetais/química , Trigonella/química , Antibacterianos/síntese química , Antibacterianos/farmacologia , Compostos Azo/química , Catálise , Escherichia coli/efeitos dos fármacos , Química Verde , Nanopartículas Metálicas/toxicidade , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Fotólise/efeitos dos fármacos , Fotólise/efeitos da radiação , Sementes/química , Sementes/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos , Termogravimetria , Trigonella/metabolismo , Raios Ultravioleta , Difração de Raios X
16.
Anal Bioanal Chem ; 408(23): 6269-81, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27565791

RESUMO

Bacteria or their protein and peptide entity enrichment using biomolecules-functionalized magnetic nanoparticles, and analysis by matrix assisted laser desorption/ionization mass spectrometry (MALDI MS) is a promising technique to analyze microorganisms. High and low molecular weight proteins like penicillin-binding proteins are responsible for final step synthesis of peptidoglycan biosynthesis; those are the target of lactam antibiotics. In this paper, we synthesized magnetic nanoparticles (mag-NPs) and further modified them with 3-aminopropyltriethoxysilane, and then the ß-lactam antibiotic amoxicillin was covalently linked to their surface. ß-Lactam group attributes as penicillin binding proteins (PBPs) in bacteria. Staphylococcus aureus and Escherichia coli were used as model bacteria for enrichment based on the ß-lactam affinity of magnetic nanoparticles, and then the bacteria were easily separated by an external magnet. Several high molecular weight penicillin binding proteins (PBPs) were detected by MALDI MS containing 10(4) and 10(3) colony-forming unit (cfu) per milileter (mL) of S. aureus and E. coli, respectively. In the case of E. coli, higher molecular weight PBPs were observed at 20 to 55 kDa in MALDI mass spectra. However, S. aureus bacteria resulted with femAB operon-based proteins, with molecular weight of 49570.4 Da, by MALDI MS after using amoxicillin functionalized-mag-NPs. The current approach provides an effective bacteria detection and preconcentration method that has high potential in the near future for fast and sensitive diagnosis of pathogenic bacteria infection. Graphical Abstract Schematic for large proteins analysis by MALDI TOF MS (a) mag-NPs and bacterial interaction (b) Penicillin binding proteins trapping by Amox-mag-NPs.


Assuntos
Amoxicilina/química , Proteínas de Bactérias/análise , Escherichia coli/química , Nanopartículas de Magnetita/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Staphylococcus aureus/química , Proteínas de Bactérias/isolamento & purificação , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Humanos , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/isolamento & purificação
17.
Rapid Commun Mass Spectrom ; 30(13): 1443-53, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-27321831

RESUMO

RATIONALE: Phosphorylation is a post-translational modification of proteins that plays very important role in a large number of biological processes. However, despite recent advancements in phosphoproteome research, large-scale detection and characterization of phosphopeptides by mass spectrometry (MS) is still a challenging task due to the low abundance of phosphopeptides and sub-stoichiometric nature of phosphorylation sites. On-particle microwave-assisted trypsin digestion of phosphoproteins and enrichment of phosphopeptides is an effective method for identification/characterization of phosphopeptides. Magnetic nanoparticles typically can absorb microwave radiation and generate heat in order to resolve complex phosphproteins and to enhance the digestion rate and capture the phosphopeptides on their modified surfaces. METHODS: In this study, we used a cheap and efficient method for rapid microwave-assisted tryptic digestion of phosphoproteins and simultaneous enrichment of phosphopeptides using CoFe2 O4 -ZnO magnetic nanoparticles. Using this technique, the digestion time of phosphoproteins can be reduced and the phosphopeptides can be quickly analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS). For the first time, we have applied CoFe2 O4 -ZnO magnetic nanoparticles for enrichment of phosphopeptides from standard phosphoproteins (ß-casein and ovalbumin), complex samples (human serum and egg white) and a protein mixture of ß-casein and BSA (1:100). RESULTS: Our results demonstrate that the capture efficiency of CoFe2 O4 -ZnO nanoparticles for ß-casein and ovalbumin in MALDI-TOFMS is very high (detection limits 0.2 fmol and 20 fmol, respectively). The CoFe2 O4 -ZnO nanoparticles have high affinity for phosphopeptide enrichment for ß-casein in complex mixtures with BSA at 1:10 and 1:100 molar ratios in the microwave within 30 s. CONCLUSIONS: Compared with other reported magnetic nanoparticles, the CoFe2 O4 -ZnO nanoparticles are easy to prepare and handle, and can save time in the phosphopeptide enrichment procedure, making these nanoparticle a good choice for highly sensitive phosphopeptide enrichment. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Micro-Ondas , Nanopartículas , Fosfopeptídeos/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Caseínas , Humanos , Fosfoproteínas
18.
Talanta ; 130: 78-89, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25159382

RESUMO

We developed a cancer chip by nano-patterning a highly sensitive SAM titanium surface capable of capturing and sensing concentrations as low as 10 cancer cells/mL from the environment by Matrix Assisted Laser Desorption and Ionization Time of Flight Mass Spectrometry (MALDI-TOF MS). The current approach evades any form of pretreatment and sample preparation processes; it is time saving and does not require the (expensive) conventional MALDI target plate. The home made aluminium (Al) target holder cost, on which we loaded the cancer chips for MALDI-TOF MS analysis, is about 60 USD. While the conventional stainless steel MALDI target plate is more than 700 USD. The SAM surface was an effective platform leading to on-chip direct MALDI-MS detection of cancer cells. We compared the functionality of this chip with the unmodified titanium surfaces and thermally oxidized (TO) titanium surfaces. The lowest detectable concentration of the TO chip was 10(3) cells/mL, while the lowest detectable concentration of the control or unmodified titanium chips was 10(6) cells/mL. Compared to the control surface, the SAM cancer chip showed 100,000 times of enhanced sensitivity and compared with the TO chip, 1000 times of increased sensitivity. The high sensitivity of the SAM surfaces is attributed to the presence of the rutile SAM, surface roughness and surface wettability as confirmed by AFM, XRD, contact angle microscope and FE-SEM. This study opens a new avenue for the potent application of the SAM cancer chip for direct cancer diagnosis by MALDI-TOF MS in the near future.


Assuntos
Neoplasias/química , Neoplasias/patologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/instrumentação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Titânio/química , Técnicas Biossensoriais , Humanos , Microscopia de Força Atômica , Células Tumorais Cultivadas , Difração de Raios X
19.
Biomaterials ; 34(23): 5833-42, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23642996

RESUMO

This study demonstrates the effective synthesis of five different sized/shaped Pt NPs, within a narrow size regime of 1-21 nm using a modified methodology and the toxicity/biocompatibility of Pt NPs on Neuro 2A cancer cells was investigated elaborately by using light microscopic observations, tryphan blue exclusion assay, MTT assay and ICP-MS. The Pt NPs-C with sizes 5-6 nm showed superior non-cytotoxic property compared to the other four Pt NPs. These non-cytotoxic Pt NPs were employed for successful photothermal treatment of Neuro 2A cell lines using near-IR 1064 nm of laser irradiation. The Pt NPs-C could generate a 9 °C increase in temperature leading to effective photothermal killing of cancer cells. The MALDI-MS was used to prove the possibility of apoptosis related triggering of cell death in the presence of the Pt NPs. The results confirm that the current approach is an effective platform for in vivo treatment of neuro cancer cells.


Assuntos
Hipertermia Induzida , Nanopartículas/uso terapêutico , Fototerapia , Platina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Materiais Biocompatíveis/farmacologia , Linhagem Celular Tumoral , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Indóis/farmacologia , Lasers , Camundongos , Nanopartículas/ultraestrutura , Tamanho da Partícula , Platina/uso terapêutico , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrofotometria Atômica , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
20.
Talanta ; 107: 167-75, 2013 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-23598208

RESUMO

For the first time, we demonstrate the use of TiO2 nanoparticles (NPs) for enhancing the carotenoid production by the extremophilic haloarchea, Haloferax mediterranei. TiO2 NPs at optimal concentration of 375 mg/L results in a 95% increase in the production of carotenoid pigment compared to the control (no TiO2 NPs). The carotenoid pigments extracted from TiO2 NPs treated H. mediterranei cells, were separated using thin layer chromatography (TLC). The separated carotenoid spots were subjected directly for MALDI MS detection. To limit the sample diffusion during matrix addition on TLC plates, a simple bordering mode was exercised. Using this method we were able to detect the pigments successfully using MALDI-MS, directly from TLC plates after separation. In addition, we also applied the Pt NPs capped with ODT via Liquid-liquid microextraction (LLME) for extracting the pigment molecules from the halobacteria in MALDI-MS. These novel NP approaches possess numerous advantages such as; rapidity, ease in synthesis, high sensitivity and low cost.


Assuntos
Carotenoides/análise , Haloferax mediterranei/química , Microextração em Fase Líquida/métodos , Pigmentos Biológicos/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Carotenoides/isolamento & purificação , Carotenoides/metabolismo , Cromatografia em Camada Fina/economia , Cromatografia em Camada Fina/métodos , Haloferax mediterranei/metabolismo , Microextração em Fase Líquida/economia , Nanopartículas/química , Nanopartículas/ultraestrutura , Pigmentos Biológicos/isolamento & purificação , Pigmentos Biológicos/metabolismo , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/economia , Titânio/química
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