Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
ACS Omega ; 9(30): 32706-32716, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39100358

RESUMO

Hydrogels have emerged as a potential tool for enhancing bioavailability and regulating the controlled release of therapeutic agents. Owing to its excellent biocompatibility, silk sericin-based hydrogels have garnered interest in biomedical applications. This study focuses on synthesizing a soft hydrogel by blending silk sericin (SS) and polycaprolactone (PCL) at room temperature. The physicochemical characteristics of the hydrogels have been estimated by different analytical techniques such as UV-visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The rheological studies demonstrate the non-Newtonian behavior of the hydrogels. Further, the porosity analysis indicates a commendable absorption capacity of the hydrogels. The swelling degree of the hydrogels has been checked in both distilled water and buffer solutions of different pHs (2-10). Moreover, the drug release profile of the hydrogels, using diclofenac sodium (DS) as a model drug, has revealed a substantial release of approximately 67% within the first 130 min with a drug encapsulation efficiency of 60.32%. Moreover, both the empty and the drug-loaded hydrogels have shown antibacterial properties against Gram-positive and Gram-negative bacteria, with the drug-loaded hydrogels displaying enhanced effectiveness. Additionally, the prepared hydrogels are biodegradable, demonstrating their future prospects in biomedical applications.

2.
Langmuir ; 40(18): 9751-9760, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38642056

RESUMO

The potential for sustainable energy and carbon neutrality has expanded with the development of a highly active electrocatalyst for the oxygen evolution reaction (OER). Covalent Organic Frameworks (COF) have recently garnered attention because of their enormous potential in a number of cutting-edge application sectors, such as gas storage, sensors, fuel cells, and active catalytic supports. A simple and effective COF constructed and integrated by post-alteration plasma modification facilitates high electrocatalytic OER activity under alkaline conditions. Variations in parameters such as voltage and treatment duration have been employed to enhance the factor that demonstrates high OER performance. The overpotential and Tafel slope are the lowest of all when using an optimized parameter, such as plasma treatment for 30 min utilizing 6 kV of voltage, PT-30 COF, measuring 390 mV at a current density of 10 mA.cm-2 and 69 mV.dec-1, respectively, as compared to 652 mV and 235 mV.dec-1 for the Pristine-COF. Our findings provide a method for broadening the scope by post-functionalizing the parent framework for effective water splitting.

3.
Nanoscale ; 15(43): 17570-17582, 2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-37873646

RESUMO

Monitoring therapeutic drugs and their elimination is crucial because they may cause severe side effects on the human body. Methotrexate (MTX) is a widely used anti-cancer drug, which is highly expensive, and the detection of unwanted overdoses of MTX using traditional procedures is time-consuming and involves complex instrumentation. In this work, we have developed a nanocomposite material using phosphorene, cystine, and gold (Ph-Cys-Au) that shows excellent optical properties. This nanocomposite can be used as an optical sensing platform for the detection of MTX in the range 0-260 µM. The synthesized sensing platform is very sensitive, selective, and cost-effective for the detection of MTX. Ph-Cys-Au can effectively detect MTX in aqueous media with a limit of detection (LOD) of about 0.0266 nM (for a linear range of 0-140 µM) and 0.0077 nM (for a linear range of 160-260 µM). The nanocomposite is equally selective for real samples, such as human blood serum (HBS) and artificial urine (AU) with a LOD of 0.0914 nM and 0.0734 nM, respectively. We have also determined the limit of quantification (LOQ); the LOQ values for the aqueous media were 0.0807 nM (for a linear range of 0-140 µM) and 0.0234 nM (for a linear range of 160-260 µM), whereas, the values for HBS and AU were around 0.2771 nM and 0.2226 nM, respectively. Moreover, the nanocomposite also provides a feasible platform for cytotoxicity screening in cancerous cells (Caco-2 cell lines) and non-cancerous cells (L-929 cell lines).


Assuntos
Antineoplásicos , Humanos , Células CACO-2 , Antineoplásicos/farmacologia , Metotrexato/farmacologia , Cistina , Ouro/farmacologia
4.
ACS Omega ; 8(39): 36065-36075, 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37810656

RESUMO

Covalent organic framework (COF) materials have greatly expanded their range in a variety of applications since the cognitive goal of a highly organized and durable adsorbent is quite rational. The characteristics of a conjugated organic framework are combined with an industrially relevant polymer to produce a composite membrane optimized for selectively adsorbing carbon dioxide (CO2) gas across a wide temperature range. Additionally, treatment of the composite membrane with cold atmospheric plasma (CAP) that specifically enhanced the parent membrane's surface area by 36% is established. Following CAP treatment, the membrane accelerates the CO2 uptake by as much as 66%. This is primarily due to a Lewis acid-base interaction between the electron-deficient carbon atom of CO2 and the newly acquired functionalities on the COFs@PVDF membrane's surface. In particular, the C-N bonds, which appear to be a higher electron density site, play a key role in this interaction. Moreover, the empirical model proposed here has confirmed CO2 adsorption phenomena in the COF@PVDF composite membrane, which closely matches the findings from the experimental data set under designated operating conditions. As a result, the current study may pave the way for future design work as well as refine the covalent framework polymer composite membrane's features, revealing a more sophisticated approach to addressing CO2 capture problems.

5.
ACS Omega ; 8(24): 21914-21928, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37360495

RESUMO

The abuse of tetracycline (TC) antibiotics causes the accumulation of their residue in the environment, which has an irreversible impact on food safety and human health. In light of this, it is vital to offer a portable, quick, efficient, and selective sensing platform to detect TC instantly. Herein, we have successfully developed a sensor using silk fibroin-decorated thiol-branched graphene oxide quantum dots through a well-known thiol-ene click reaction. It is applied to ratiometric fluorescence sensing of TC in real samples in the linear range of 0-90 nM, with the detection limit of 49.69, 47.76, 55.25, 47.90, and 45.78 nM for deionized water, chicken sample, fish sample, human blood serum, and honey sample, respectively. With the gradual addition of TC to the liquid media, the sensor develops a synergetic luminous effect in which the fluorescence intensity of the nanoprobe steadily declines at 413 nm, while the intensity of a newly emerging peak increases at 528 nm, maintaining a ratio that is dependent on the analyte concentration. The increase of luminescence properties in the liquid media is clearly visible by naked eyes in the presence of 365 nm UV light. The result helps us in building a filter paper strip-based portable smart sensor using an electric circuit comprising a 365 nm LED (light-emitting diode) powered by a mobile phone battery which is attached just below the rear camera of a smartphone. The camera of the smartphone captures the color changes that occur throughout the sensing process and translates into readable RGB data. The dependency of color intensity with respect to the concentration of TC was evaluated by deducing a calibration curve from where the limit of detection was calculated and found to be 0.125 µM. These kinds of gadgets are important for the possible real-time, on-the-spot, quick detection of analytes in situations where high-end approaches are not easily accessible.

6.
Chemistry ; 29(38): e202300756, 2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37186106

RESUMO

The cognitive intent of a highly ordered and robust adsorbent is extremely sensible and, in this context, Covalent Organic Framework (COF) materials have significantly burgeoned their scope in diverse applications. Herein, a simple time-competent hydrothermal procedure is presented to construct a covalent framework with an ultrahigh surface area of 1428 m2 /g that shows active adsorption of carbon dioxide (CO2 ) at variable temperature ranges. Moreover, a facile scalably controlled post-synthetic air liquid interfacial plasma (ALIP) induced protocol is substantiated that explicitly amplifies the surface area of the pristine framework even to a higher value of 2051 m2 /g. The post-synthetic plasma approach presented here led to the rapid enhancement of the surface area of the pristine COF by 43 %, which concurrently advances the CO2 uptake up to 67 %. Hence, the current study may open up a new frontier in the design as well as fine-tune the properties of the covalent framework that unfolds the advanced outlook in addressing the challenges of CO2 capture.


Assuntos
Dióxido de Carbono , Estruturas Metalorgânicas , Adsorção , Transporte Biológico , Software
7.
RSC Adv ; 11(56): 35274-35279, 2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-35493194

RESUMO

Organic entities like suitably functionalized naphthalene diimide (NDI) exhibited logical behaviours in response to various external stimuli and can be used to develop digital logic operations. The present findings include utilization of two congeners of NDI i.e., N1 and N2 for the successive turning ON/OFF of fluorescence with inclusion of acid and base. The recognition of the switching phenomenon of the probes N1 and N2 are applied to construct fundamental digital logic gates such as NOT, YES, IMPLICATION, INHIBIT, etc. The inputs to each of the logic gates are defined by the presence or absence of acid and base. Accordingly, the outputs generated from the gates are in the form of fluorescence ON or OFF status denoted by "1" and "0" respectively. Likewise, we have adopted Boolean algebra and its associated De-Morgan's theorem to build the combined logic gates such as XOR and XNOR gates. The proposed logic gates are validated by the optical behaviour of the congeners N1 and N2 in response to acid as well as base and the experimental results are confirmed by the theoretical predictions. The proposed work can have potential applications in next-generation logic based analytical applications.

8.
RSC Adv ; 11(45): 28313-28319, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-35480746

RESUMO

Real time detection of explosive compounds in today's time is of utmost necessity due to security and severe environmental safety issues. Herein, we have synthesized a biobased conjugated molecular system from riboflavin and l-cystine utilized it for detecting picric acid in trace amount using optical sensing technique. The bioconjugate probe showed high quenching efficiency towards picric acid, which is 92.2%. In depth mechanistic study showed that ground state electrostatic interaction and inner filter effect are the factors leading to the diminishing of the probe's fluorescence intensity on addition of trace amount of the nitrophenol, picric acid. The detection limit of the conjugate is 0.37 nM which is extremely low and highly desirable for clinical applications of this system.

9.
ACS Appl Mater Interfaces ; 7(21): 11195-202, 2015 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-25955402

RESUMO

Rapid detection of picric acid in real sample is of outmost importance from the perspective of health, safety, and environment. In this study, a very simple and cost-effective detection of picric acid is accomplished by developing a couple of biobased conjugates curcumin-cysteine (CC) and curcumin-tryptophan (CT), which undergo efficient fluorescence turn on toward picric acid in aqueous media. Both the probes experience about 26.5-fold fluorescence enhancements at 70 nM concentration of the analyte. Here, the fluorescence turn on process is governed by the aggregation induced emission, which is induced from the electrostatic interaction between the conjugates with picric acid. The detection limit of CC and CT are about 13.51 and 13.54 nM of picric acid, respectively. Importantly, both the probes exhibit high selectivity and low interference of other analogues toward the detection of picric acid. In addition, the probes are highly photostable, show low response time and are practically applicable for sensing picric acid in real environmental samples, which is the ultimate goal of this work.


Assuntos
Curcumina/química , Cisteína/química , Monitoramento Ambiental/métodos , Picratos/análise , Triptofano/química , Poluentes Químicos da Água/análise , Nanoconjugados/química , Picratos/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Água/química
10.
Analyst ; 139(24): 6502-10, 2014 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-25343270

RESUMO

The development of a rapid, label free, cost effective and highly efficient sensor for DNA detection is of great importance in disease diagnosis. Herein, we have reported a new hybrid fluorescent probe based on a cationic curcumin-tryptophan complex and water soluble mercapto succinic acid (MSA) capped CdTe quantum dots (QDs) for the detection of double stranded DNA (ds DNA) molecules. The cationic curcumin-tryptophan complex (CT) directly interacts with negatively charged MSA capped quantum dots via electrostatic coordination, resulting in photoluminescence (PL) quenching of QDs via the Photoinduced Electron Transfer (PET) process. Further, addition of ds DNA results in restoration of PL, as CT would intercalate between DNA strands. Thus, this process can be utilized for selective sensing of ds DNA via fluorescence measurements. Under optimized experimental conditions, the PL quenching efficiency of QDs is found to be 99.4% in the presence of 0.31 × 10(-9) M CT. Interestingly, the regain in PL intensity of QD-CT is found to be 99.28% in the presence of 1 × 10(-8) M ds DNA. The detection limit for ds DNA with the developed sensing probe is 1.4 × 10(-10) M. Furthermore, the probe is found to be highly sensitive towards bacterial DNA isolated from Streptomyces sanglieri with a detection limit of 1.7 × 10(-6) M. The present work will provide a new insight into preparation of bio-inspired hybrid materials as efficient sensors for disease diagnosis and agricultural development.


Assuntos
Compostos de Cádmio/química , DNA Bacteriano/análise , Corantes Fluorescentes/química , Pontos Quânticos/química , Streptomyces/isolamento & purificação , Telúrio/química , Curcumina/química , Transporte de Elétrons , Substâncias Intercalantes/química , Limite de Detecção , Microbiologia do Solo , Espectrometria de Fluorescência/métodos , Streptomyces/química , Triptofano/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA