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1.
Opt Express ; 32(2): 1314-1324, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38297686

RESUMEN

Nitrogen-containing high-energy organic compounds represent a class of materials with critical implications in various fields, including military, aerospace, and chemical industries. The precise characterization and analysis of these compounds are essential for both safety and performance considerations. Spectroscopic characterization in the far-infrared region has great potential for non-destructive investigation of high energetic and related compounds. This research article presents a comprehensive study of common organic energetic materials in the far-infrared region (5-200 cm-1), aiming to enhance security measures through the utilization of cutting-edge spectroscopic techniques. Broadband terahertz time-domain spectroscopy and ultra-low frequency Raman spectroscopy are employed as powerful tools to probe the vibrational and rotational modes of various explosive materials. One of the key objectives of this present work is unveiling the characteristic spectral features and optical parameters of five common nitrogen based high energy organic compounds towards rapid and accurate identification. Further, we have explored the potential of terahertz reflection imaging for non-contact through barrier sensing, a critical requirement in security applications. Based on the spectral features obtained from the spectroscopic studies and using advanced imaging algorithms we have been able to detect these compounds under various barriers including paper, cloth, backpack, etc. Subsequently, this study highlights the capabilities of the two techniques offering a pathway to enhance their utility over a wide range of practical security applications.

2.
Opt Express ; 31(15): 23877-23888, 2023 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-37475228

RESUMEN

The response of terahertz to the presence of water content makes it an ideal analytical tool for hydration monitoring in agricultural applications. This study reports on the feasibility of terahertz sensing for monitoring the hydration level of freshly harvested leaves of Celtis sinensis by employing a imaging platform based on quantum cascade lasers and laser feedback interferometry. The imaging platform produces wide angle high resolution terahertz amplitude and phase images of the leaves at high frame rates allowing monitoring of dynamic water transport and other changes across the whole leaf. The complementary information in the resulting images was fed to a machine learning model aiming to predict relative water content from a single frame. The model was used to predict the change in hydration level over time. Results of the study suggest that the technique could have substantial potential in agricultural applications.

3.
Biomacromolecules ; 24(8): 3638-3646, 2023 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-37478281

RESUMEN

Antibody drug conjugates (ADCs) are poised to have an enormous impact on targeted nanomedicine, especially in many cancer pathologies. The reach of the current format of ADCs is limited by their low drug-to-antibody ratio (DAR) because of the associated physiochemical instabilities. Here, we design antibody polymer conjugates (APCs) as a modular strategy to utilize polymers to address ADC's shortcomings. We show here that conjugation of polymer-based therapeutic molecules to antibodies helps increase the DAR, owing to the hydrophilic comonomer in the polymer that helps in masking the increased hydrophobicity caused by high drug loading. We show that the platform exhibits cell targetability and selective cell killing in multiple cell lines expressing disease-relevant antigens, viz., HER2 and EGFR. The ability to use different functionalities in the drug as the handle for polymer attachment further demonstrates the platform nature of APCs. The findings here could serve as an alternative design strategy for the next generation of active targeted nanomedicine.


Asunto(s)
Antineoplásicos , Inmunoconjugados , Anticuerpos , Inmunoconjugados/química , Preparaciones Farmacéuticas , Antígenos , Polímeros , Antineoplásicos/química
4.
Biomacromolecules ; 24(2): 849-857, 2023 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-36639133

RESUMEN

Targeted drug delivery using antibody-drug conjugates has attracted great attention due to its enhanced therapeutic efficacy compared to traditional chemotherapy. However, the development has been limited due to a low drug-to-antibody ratio and laborious linker-payload optimization. Herein, we present a simple and efficient strategy to combine the favorable features of polymeric nanocarriers with antibodies to generate an antibody-nanogel conjugate (ANC) platform for targeted delivery of cytotoxic agents. Our nanogels stably encapsulate several chemotherapeutic agents with a wide range of mechanisms of action and solubility. We showcase the targetability of ANCs and their selective killing of cancer cells over-expressing disease-relevant antigens such as human epidermal growth factor receptor 2, epidermal growth factor receptor, and tumor-specific mucin 1, which cover a broad range of breast cancer cell types while maintaining low to no toxicity to non-targeted cells. Overall, our system represents a versatile approach that could impact next-generation nanomedicine in antibody-targeted therapeutics.


Asunto(s)
Antineoplásicos , Inmunoconjugados , Neoplasias , Humanos , Nanogeles , Neoplasias/tratamiento farmacológico , Inmunoconjugados/farmacología , Inmunoconjugados/uso terapéutico , Sistemas de Liberación de Medicamentos , Línea Celular Tumoral
5.
Environ Res ; 231(Pt 2): 116145, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37217127

RESUMEN

Water pollution due to textile industry effluents is a global concern that warrants versatile research solutions for degrading them, and for a sustainable environment. In the present work, by using the imperative role of nanotechnology, a facile one-pot synthesis has been devised to generate κ-carrageenan capped silver nanocatalyst (CSNC), and was immobilized on 2D bentonite (BT) sheets to generate nanocatalytic platform (BTCSNC) for the degradation of anionic azo dyes. The nanocomposite(s) were physicochemically characterized using UV-Vis, DLS, TEM, FESEM, PXRD, ATR-FTIR, TGA, BET and XPS etc., to obtain insights into the nanocomposite composition, structure, stability, morphology and mechanism of interaction. The obtained CNSC are monodispersed, spherical with a size of 4 ± 2 nm, and were stabilized by the functional groups (-OH, COO‾, and SO3‾) of κ-Crg. The broadening of peak corresponding to basal plane (001) of BT montmorillonite in PXRD spectra established its exfoliation upon addition of CSNC. XPS and ATR-FTIR data evidenced the absence of covalent interactions between CSNC and BT. The catalytic efficiency of CSNC and BTCSNC composites were compared for the degradation of methyl orange (MO) and congo red (CR). The reaction followed a pseudo first order kinetics, and immobilization of CSNC on BT resulted in a 3-4 fold enhancement in degradation rates. The rates achieved for the degradation kinetics are: MO degradation within 14 s (Ka 9.86 ± 2.00 min-1), and CR degradation within 120 s (Ka of 1.24 ± 0.13 min-1). Further, a degradation mechanism has been proposed by analyzing the products identified through LC-MS. The reusability studies of the BTCSNC evidenced the complete activity of the nanocatalytic platform for six cycles, and gravitational separation method for catalyst recycling. In a nutshell, the current study provided an environmentally friendly, sizable, and sustainable nano catalytic platform" for the remediation of industrial wastewater contaminated with hazardous azo dyes".


Asunto(s)
Bentonita , Plata , Plata/química , Carragenina , Rojo Congo/química , Compuestos Azo
6.
Sensors (Basel) ; 23(20)2023 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-37896654

RESUMEN

In this paper, we propose a reconfigurable intelligent surface (RIS) that can dynamically switch the transmission and reflection phase of incident electromagnetic waves in real time to realize the dual-beam or quad-beam and convert the polarization of the transmitted beam. Such surfaces can redirect a wireless signal at will to establish robust connectivity when the designated line-of-sight channel is disturbed, thereby enhancing the performance of wireless communication systems by creating an intelligent radio environment. When integrated with a sensing element, they are integral to performing joint detection and communication functions in future wireless sensor networks. In this work, we first analyze the scattering performance of a reconfigurable unit element and then design a RIS. The dynamic field scattering manipulation capability of the RIS is validated by full-wave electromagnetic simulations to realize six different functions. The scattering characteristics of the proposed unit element, which incorporates two p-i-n diodes have been substantiated through practical implementation. This involved the construction of a simple prototype and the subsequent examination of its scattering properties via the free-space measurement method. The obtained transmission and reflection coefficients from the measurements are in agreement with the anticipated outcomes from simulations.

7.
Sensors (Basel) ; 23(5)2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36904925

RESUMEN

To reduce the water footprint in agriculture, the recent push toward precision irrigation management has initiated a sharp rise in photonics-based hydration sensing in plants in a non-contact, non-invasive manner. Here, this aspect of sensing was employed in the terahertz (THz) range for mapping liquid water in the plucked leaves of Bambusa vulgaris and Celtis sinensis. Two complementary techniques, broadband THz time-domain spectroscopic imaging and THz quantum cascade laser-based imaging, were utilized. The resulting hydration maps capture the spatial variations within the leaves as well as the hydration dynamics in various time scales. Although both techniques employed raster scanning to acquire the THz image, the results provide very distinct and different information. Terahertz time-domain spectroscopy provides rich spectral and phase information detailing the dehydration effects on the leaf structure, while THz quantum cascade laser-based laser feedback interferometry gives insight into the fast dynamic variation in dehydration patterns.

8.
Bioconjug Chem ; 33(3): 486-495, 2022 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-35139308

RESUMEN

Targeted delivery of chemotherapeutic drugs can improve their therapeutic efficiency by localizing their toxic effects at the diseased site. This is often achieved either by direct conjugation of drugs to antibodies targeting overexpressed receptors on cancer cells (antibody-drug conjugates/ADCs) or by conjugating antibodies to nanoparticles bearing drugs (antibody-nanoparticle conjugates/ANCs). Here, we report a platform for utilizing hinge cysteines on antigen-binding fragment (Fab') of an anti-CD4 antibody for site-specific conjugation to nanoparticles giving rise to anti-CD4 Fab'-nanoparticle conjugates (Fab'-NCs). We demonstrate a convenient route for obtaining functional anti-CD4 Fab' from full-length antibody and examine the targeted delivery efficiencies of anti-CD4 Fab'-NCs vs ANCs for selective delivery to CD4high mT-ALL cells. Our results indicate that higher avidity of full-length anti-CD4 antibody, i.e., protein alone translated to higher binding ability to CD4high mT-ALL cells in comparison with anti-CD4 Fab' alone. However, the targeted delivery efficiency of anti-CD4 Fab'-NCs was comparable to ANCs indicating that the avidity of Fab' is restored in a nanoparticle-conjugate format. Fab'-NCs are equally capable of achieving targeted drug delivery to CD4high T-cells as ANCs and are a versatile alternative to ANCs by offering site-selective modification strategy while retaining their advantages.


Asunto(s)
Inmunoconjugados , Nanopartículas , Anticuerpos Monoclonales , Linfocitos T CD4-Positivos , Fragmentos Fab de Inmunoglobulinas
9.
Angew Chem Int Ed Engl ; 60(23): 12813-12818, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33768625

RESUMEN

We report here on protein-antibody conjugates (PACs) that are used for antibody-directed delivery of protein therapeutics to specific cells. PACs have the potential to judiciously combine the merits of two prolific therapeutic approaches-biologics and antibody-drug conjugates. We utilize spherical polymer brushes to construct PACs using the combination of two simple and efficient functionally orthogonal click chemistries. In addition to the synthesis and characterization of these nanoparticles, we demonstrate that PACs are indeed capable of specifically targeting cells based on the presence of target antigen on the cell surface to deliver proteins. The potentially broad adaptability of PACs opens up new opportunities for targeted biologics in therapeutics and sensing.


Asunto(s)
Anticuerpos/química , Fulerenos/química , Receptor ErbB-2/química , Línea Celular Tumoral , Humanos , Nanopartículas/química , Tamaño de la Partícula
10.
Biomacromolecules ; 21(6): 2473-2481, 2020 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-32383874

RESUMEN

CD4+ T lymphocytes play an important role in controlling many malignancies. The modulation of CD4+ T cells through immunomodulatory or cytotoxic drugs could change the course of disease progression for disorders such as autoimmunity, immunodeficiency, and cancer. Here, we demonstrate that anti-CD4 conjugated polymeric nanogels can deliver a small molecule cargo to primary CD4+ T cells and a CD4high T cell lymphoma. The antibody conjugation not only increased the uptake efficiency of the nanogel (NG) by CD4+ T cells but also decreased the non-specific uptake of the NG by CD4- lymphocytes. For T lymphoma cell lines, the mertansine-loaded conjugate displayed a dose-dependent cell growth inhibition at 17 ng/mL antibody concentration. On the other hand, antibody-drug conjugate (ADC)-type formulation of the anti-CD4 reached similar levels of cell growth inhibition only at the significantly higher concentration of 1.8 µg/mL. NG and antibody conjugates have the advantage of carrying a large payload to a defined target in a more efficient manner as it needs far less antibody to achieve a similar outcome.


Asunto(s)
Antineoplásicos , Inmunoconjugados , Maitansina , Linfocitos T CD4-Positivos , Nanogeles
11.
Funct Integr Genomics ; 19(2): 329-348, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30465139

RESUMEN

Terminal heat stress has detrimental effect on the growth and yield of wheat. Very limited information is available on heat stress-associated active proteins (SAAPs) in wheat. Here, we have identified 159 protein groups with 4271 SAAPs in control (22 ± 3 °C) and HS-treated (38 °C, 2 h) wheat cvs. HD2985 and HD2329 using iTRAQ. We identified 3600 proteins to be upregulated and 5825 proteins to be downregulated in both the wheat cvs. under HS. We observed 60.3% of the common SAAPs showing upregulation in HD2985 (thermotolerant) and downregulation in HD2329 (thermosusceptible) under HS. GO analysis showed proton transport (molecular), photosynthesis (biological), and ATP binding (cellular) to be most altered under HS. Most of the SAAPs identified were observed to be chloroplast localized and involved in photosynthesis. Carboxylase enzyme was observed most abundant active enzymes in wheat under HS. An increase in the degradative isoenzymes (α/ß-amylases) was observed, as compared to biosynthesis enzymes (ADP-glucophosphorylase, soluble starch synthase, etc.) under HS. Transcript profiling showed very high relative fold expression of HSP17, CDPK, Cu/Zn SOD, whereas downregulation of AGPase, SSS under HS. The identified SAAPs can be used for targeted protein-based precision wheat-breeding program for the development of 'climate-smart' wheat.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Respuesta al Choque Térmico , Proteínas de Plantas/genética , Proteoma/genética , Termotolerancia , Triticum/genética , Proteínas de Plantas/metabolismo , Proteoma/metabolismo , Transcriptoma , Triticum/metabolismo
12.
Bioconjug Chem ; 30(4): 1028-1041, 2019 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-30830750

RESUMEN

Proteins have sparked fast growing interest as biological therapeutic agents for several diseases. Antibodies, in particular, carry an enormous potential as drugs owing to their remarkable target specificity and low immunogenicity. Although the market has numerous antibodies directed toward extracellular targets, their use in targeting therapeutically important intracellular targets is limited by their inability to cross cellular membrane. Realizing the potential for antibody therapy in disease treatment, progress has been made in the development of methods to deliver antibodies intracellularly. In this review, we address various platforms for delivery of antibodies and their merits and drawbacks.


Asunto(s)
Anticuerpos/administración & dosificación , Animales , Anticuerpos/uso terapéutico , Péptidos de Penetración Celular/administración & dosificación , Sistemas de Liberación de Medicamentos , Humanos , Liposomas , Nanopartículas
13.
Oral Dis ; 25(1): 73-79, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30059188

RESUMEN

OBJECTIVES: To evaluate and compare the therapeutic response of lycopene and curcumin with placebo in patients suffering from oral submucous fibrosis (OSMF) and to correlate the habit variables of smoked and smokeless tobacco products in OSMF. METHODS: A randomized placebo-controlled parallel clinical study was conducted on ninety OSMF patients, who were divided into three treatment groups using computer-generated randomization. Group A patients (n = 30) were given curcumin tablet (300 mg) twice daily, Group B patients (n = 30) received lycopene capsules (8 mg) twice daily, and for Group C (n = 30), placebo capsules were given once daily for a period of six months. Both the participant and outcome assessor were blinded. Pre- and post-treatment comparison of mouth opening, burning sensation, tongue protrusion, and cheek flexibility was analyzed at periodic follow-up of 9 months. RESULTS: The overall improvement in mouth opening, burning sensation, tongue protrusion, and cheek flexibility was 3.9 ± 4.9 mm, 4.8 ± 2.6, 5.0 ± 7.2 mm, & 0.36 ± 0.71 mm, respectively, for curcumin and 4.1 ± 4.2 mm, 5.0 ± 2.3, 2.4 ± 3.5 mm, & 0.66 ± 0.80 mm, respectively, for lycopene with the p value <0.05. CONCLUSION: Statistically significant improvement in clinical findings was observed in both curcumin and lycopene treatment groups in comparison with placebo. However, the therapeutic efficacy of curcumin and lycopene was found to be almost equal in OSMF patients.


Asunto(s)
Curcumina/uso terapéutico , Licopeno/uso terapéutico , Fibrosis de la Submucosa Bucal/tratamiento farmacológico , Adolescente , Adulto , Areca , Mejilla , Femenino , Humanos , Masculino , Persona de Mediana Edad , Boca , Fumar , Tabaco sin Humo , Lengua , Adulto Joven
14.
Biomacromolecules ; 19(3): 860-871, 2018 03 12.
Artículo en Inglés | MEDLINE | ID: mdl-29360342

RESUMEN

Here, we have exploited the heightened extracellular concentration of matrix metalloproteinase-9 (MMP-9) to induce surface-conversional properties of nanogels with the aim of tumor-specific enhanced cellular uptake. A modular polymeric nanogel platform was designed and synthesized for facile formulation and validation of MMP-9-mediated dePEGylation and generation of polyamine-type surface characteristics through peptide N-termini. Nanogels containing MMP-9-cleavable motifs and different poly(ethylene glycol) corona lengths (350 and 750 g/mol) were prepared, and enzymatic surface conversional properties were validated by MALDI characterization of cleaved byproducts, fluorescamine assay amine quantification, and zeta potential. The nanogel with a shorter PEG length, mPEG350-NG, exhibited superior surface conversion in response to extracellular concentrations of MMP-9 compared to that of the longer PEG length, mPEG750-NG. Confocal microscopy images of HeLa cells incubated with both fluorescein-labeled nanogels and DiI-encapsulated nanogels demonstrated greater uptake following MMP-9 "activation" for mPEG350-NG compared to its nontreated "passive" mPEG350-NG parent, demonstrating the versatility of such systems to achieve stimuli-responsive uptake in response to cancer-relevant proteases.


Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Metaloproteinasa 9 de la Matriz/metabolismo , Nanopartículas/química , Proteínas de Neoplasias/metabolismo , Neoplasias/tratamiento farmacológico , Péptidos , Polietilenglicoles , Geles , Células HeLa , Humanos , Neoplasias/enzimología , Neoplasias/patología , Péptidos/química , Péptidos/farmacocinética , Péptidos/farmacología , Polietilenglicoles/química , Polietilenglicoles/farmacocinética , Polietilenglicoles/farmacología
15.
J Org Chem ; 83(24): 15406-15414, 2018 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-30474975

RESUMEN

Herein, nickel-catalyzed sustainable strategy for the synthesis of N-substituted pyrroles using butene-1,4-diols and butyne-1,4-diols with a series of aryl-, alkyl-, and heteroarylamines is reported. The catalytic protocol is tolerant of free alcohol, halide, alkyl, alkoxy, oxygen heterocycles, activated benzyl, and the pyridine moiety and resulted in up to 90% yield. Initial mechanistic studies involving defined nickel catalyst, determination of rate, and order of reaction including deuterium-labeling experiments were performed for pyrrole synthesis.

16.
Lasers Med Sci ; 33(8): 1739-1745, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29948450

RESUMEN

To evaluate the efficacy of laser fibrotomy in patients with oral submucous fibrosis (OSMF) and also to correlate the habit variables causing OSMF. Thirty patients diagnosed clinically and histopathologically with OSMF were included in the study. Laser fibrotomy was done under local anesthesia using Zolar diode laser (980 nm frequency) at 2-W power in contact mode with fibro-optic cutting tip. The patients were advised to practice mouth-opening exercises rigorously, and topical corticosteroid was given for burning sensation and pain for 6 months. Pre- and post-treatment comparison of mouth opening, burning sensation, tongue protrusion, and cheek flexibility was analyzed after a follow-up period of 9 months. After a follow-up period of 9 months from the surgical intervention, the mean value of difference in pre- and post-treatment of VAS score, mouth opening, and tongue protrusion was found to be 3.3 ± 2.1, 7.7 ± 5.1, 1.6 ± 2.7, and 0.38 ± 0.61 respectively. Using the Wilcoxon signed rank test, all the above difference in mean was found to be significant with p value < 0.05. With above suggested significant results, lasers can provide an alternative and better means for surgical fibrotomy, relieving trismus in moderate OSMF as they are minimally invasive, cause less hemorrhage, and have faster healing and minimal surgical site scaring and relapse.


Asunto(s)
Hábitos , Láseres de Semiconductores/uso terapéutico , Fibrosis de la Submucosa Bucal/cirugía , Adulto , Mejilla , Femenino , Estudios de Seguimiento , Humanos , Láseres de Semiconductores/efectos adversos , Masculino , Persona de Mediana Edad , Cuidados Posoperatorios , Resultado del Tratamiento , Escala Visual Analógica , Adulto Joven
17.
Funct Integr Genomics ; 17(6): 621-640, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28573536

RESUMEN

Global warming is a major threat for agriculture and food security, and in many cases the negative impacts are already apparent. Wheat is one of the most important staple food crops and is highly sensitive to the heat stress (HS) during reproductive and grain-filling stages. Here, whole transcriptome analysis of thermotolerant wheat cv. HD2985 was carried out at the post-anthesis stage under control (22 ± 3 °C) and HS-treated (42 °C, 2 h) conditions using Illumina Hiseq and Roche GS-FLX 454 platforms. We assembled ~24 million (control) and ~23 million (HS-treated) high-quality trimmed reads using different assemblers with optimal parameters. De novo assembly yielded 52,567 (control) and 59,658 (HS-treated) unigenes. We observed 785 transcripts to be upregulated and 431 transcripts to be downregulated under HS; 78 transcripts showed >10-fold upregulation such as HSPs, metabolic pathway-related genes, etc. Maximum number of upregulated genes was observed to be associated with processes such as HS-response, protein-folding, oxidation-reduction and photosynthesis. We identified 2008 and 2483 simple sequence repeats (SSRs) markers from control and HS-treated samples; 243 SSRs were observed to be overlying on stress-associated genes. Polymorphic study validated four SSRs to be heat-responsive in nature. Expression analysis of identified differentially expressed transcripts (DETs) showed very high fold increase in the expression of catalytic chaperones (HSP26, HSP17, and Rca) in contrasting wheat cvs. HD2985 and HD2329 under HS. We observed positive correlation between RNA-seq and qRT-PCR expression data. The present study culminated in greater understanding of the heat-response of tolerant genotype and has provided good candidate genes for the marker development and screening of wheat germplasm for thermotolerance.


Asunto(s)
Aclimatación , Proteínas de Choque Térmico/genética , Respuesta al Choque Térmico , Repeticiones de Microsatélite , Proteínas de Plantas/genética , Triticum/genética , Proteínas de Choque Térmico/metabolismo , Proteínas de Plantas/metabolismo , Transcriptoma , Triticum/crecimiento & desarrollo
18.
Org Biomol Chem ; 15(22): 4822-4830, 2017 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-28530734

RESUMEN

Copper-catalyzed reaction of enynamines with sulfonylazides provides acyclic and cyclic amidines. Nucleophilic addition of the tethered amino group on the in situ generated ketenimine forms a six-membered cyclic zwitterionic intermediate which facilitates migration of the tethered amino group to the C5-center giving the acyclic amidine. On the other hand, migration of a substituent on the amino group to C2- and C4-centers results in the formation of cyclic amidines. Computational studies were carried out to validate the mechanism which indicates that the product distribution of the process depends on the substitutions on the enynamine backbone.

20.
J Nanobiotechnology ; 12: 40, 2014 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-25271044

RESUMEN

BACKGROUND: Pseudomonas aeruginosa infection is a leading cause of morbidity and mortality in burn and immune-compromised patients. In recent studies, researchers have drawn their attention towards ecofriendly synthesis of nanoparticles and their activity against multidrug resistant microbes. In this study, silver nanoparticles were synthesized from aqueous extract of Phyllanthus amarus. The synthesized nanoparticles were explored as a potent source of nanomedicine against MDR burn isolates of P. aeruginosa. RESULTS: Silver nanoparticles were successfully synthesized using P. amarus extract and the nature of synthesized nanoparticles was analyzed by UV-Vis spectroscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, dynamic light scattering, zeta potential, X- ray diffraction and fourier transform infra-red spectroscopy. The average size of synthesized nanoparticles was 15.7, 24 ± 8 and 29.78 nm by XRD, TEM and DLS respectively. The antibacterial activity of AgNPs was investigated against fifteen MDR strains of P. aeruginosa tested at different concentration. The zone of inhibition was measured in the range of 10 ± 0.53 to 21 ± 0.11mm with silver nanoparticles concentration of 12.5 to 100 µg/ml. The zone of inhibition increased with increase in the concentration of silver nanoparticles. The MIC values of synthesized silver nanoparticles were found in the range of 6.25 to12.5 µg/ml. The MIC values are comparable to the standard antibiotics. CONCLUSION: The present study suggests that silver nanoparticles from P. amarus extract exhibited excellent antibacterial potential against multidrug resistant strains of P. aeruginosa from burn patients and gives insight of their potential applicability as an alternative antibacterial in the health care system to reduce the burden of multidrug resistance.


Asunto(s)
Antibacterianos/administración & dosificación , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Nanopartículas del Metal/administración & dosificación , Phyllanthus/química , Pseudomonas aeruginosa/efectos de los fármacos , Plata/administración & dosificación , Humanos , Tamaño de la Partícula , Extractos Vegetales/administración & dosificación
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