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1.
Gels ; 10(4)2024 Mar 29.
Article in English | MEDLINE | ID: mdl-38667654

ABSTRACT

Controlled drug delivery is a key strategy aimed at reducing both the frequency of therapeutic dosages and potential systemic side effects, particularly in the case of high drug concentrations. The nanocomposite hydrogel systems presented in this study were synthesized by combining carboxymethyl cellulose, polyvinyl alcohol, and (3-aminopropyl)triethoxysilane-functionalized halloysite nanotubes (fHNTs). This hydrogel system is a potential candidate for the controlled release of cefadroxil monohydrate. These hydrogels are analyzed by Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, and rheological measurements. Additionally, swelling properties, porosity, hydrophilicity, drug release, and in vitro and in vivo analyses were also evaluated. The observed trends in swelling and drug release demonstrated that the outcomes are dependent on the presence of fHNTs in the hydrogel matrix. Notably, fHNTs-loaded hydrogels displayed sustained drug release patterns. This innovative approach eliminates the need for traditional encapsulation and presents promising and translatable strategies for achieving more effective drug release.

2.
ACS Appl Mater Interfaces ; 15(38): 45354-45366, 2023 Sep 27.
Article in English | MEDLINE | ID: mdl-37702662

ABSTRACT

The present work aims to predict the degradation in the performance of a solid oxide fuel cell (SOFC) cathode owing to cation interdiffusion between the electrolyte and cathode and surface segregation. Cation migration in the (La0.60Sr0.40)0.95Co0.20Fe0.80O3-x (LSCF)-Gd0.10Ce0.90O1.95 (GDC) composite cathode is evaluated in relation to time up to 1000 h using scanning transmission electron microscopy (STEM)-energy-dispersive X-ray spectroscopy (EDXS). The resulting insulating phase formed within the GDC interlayer is quantified by means of the volume fraction using a two-dimensional (2D) image analysis technique. For the very first time, the amount of the insulating phase in the GDC interlayer is quantified, and the corresponding performance degradation of the LSCF cathode is predicted. Mathematical relationships are established for the estimation of degradation due to surface segregation of the cathode. The ohmic resistance between the cathode and the GDC interlayer/electrolyte interface and the polarization resistance of the cathode, characterized by electrochemical impedance spectroscopy (EIS), show an excellent match with the predicted results. The combined degradation analysis and modeling for the cathode lifetime prediction provide a systematic understanding of the time-dependent cation migration and segregation behavior.

3.
Sensors (Basel) ; 23(18)2023 Sep 20.
Article in English | MEDLINE | ID: mdl-37766053

ABSTRACT

In recent years, the Internet of Things (IoT) has had a big impact on both industry and academia. Its profound impact is particularly felt in the industrial sector, where the Industrial Internet of Things (IIoT), also known as Industry 4.0, is revolutionizing manufacturing and production through the fusion of cutting-edge technologies and network-embedded sensing devices. The IIoT revolutionizes several industries, including crucial ones such as oil and gas, water purification and distribution, energy, and chemicals, by integrating information technology (IT) with industrial control and automation systems. Water, a vital resource for life, is a symbol of the advancement of technology, yet knowledge of potential cyberattacks and their catastrophic effects on water treatment facilities is still insufficient. Even seemingly insignificant errors can have serious consequences, such as aberrant pH values or fluctuations in the concentration of hydrochloric acid (HCI) in water, which can result in fatalities or serious diseases. The water purification and distribution industry has been the target of numerous hostile cyber security attacks, some of which have been identified, revealed, and documented in this paper. Our goal is to understand the range of security threats that are present in this industry. Through the lens of IIoT, the survey provides a technical investigation that covers attack models, actual cases of cyber intrusions in the water sector, a range of security difficulties encountered, and preventative security solutions. We also explore upcoming perspectives, illuminating the predicted advancements and orientations in this dynamic subject. For industrial practitioners and aspiring scholars alike, our work is a useful, enlightening, and current resource. We want to promote a thorough grasp of the cybersecurity landscape in the water industry by combining key insights and igniting group efforts toward a safe and dependable digital future.

4.
Pak J Pharm Sci ; 36(2): 525-533, 2023 Mar.
Article in English | MEDLINE | ID: mdl-37530161

ABSTRACT

Ranitidine hydrochloride (RTD), a moisture-sensitive drug, has issues of stability during shelf life especially when formulated through wet granulation method. In current study, RTD was blended with non-hygroscopic excipient like ethyl cellulose and compressed using direct compression method. The physical and physicochemical characteristics were evaluated including hardness, thickness, diameter, friability, weight variation, disintegration, dissolution and accelerated stability study to optimize findings. Subsequently, the optimized formulation was characterized for Fourier Transform Infrared (FTIR) analysis and in vitro drug release kinetics. The physical characterization was unaffected by polymer variation while the friability and weight variation were within the USP limits. In vitro drug release depicted that the release rate was sustained by increasing the amount of ethyl cellulose, with a 10% increase of ethyl cellulose 99.09% drug was released. FTIR analysis exhibited no interaction among the ingredients of the optimized formulation (E2). The optimized formulation followed Hixson-Crowell release kinetics. Formulation A5 displayed immediate release characters as plain uncoated formulation. Accelerated studies showed no significant change in the drug content. The RTD was successfully sustained to be released up to 6 h and accelerated stability showed that the optimized formulation (E2) containing 4% starch 1500 and 10% of ethyl cellulose, respectively, was stable up to 6 months.


Subject(s)
Chemistry, Pharmaceutical , Ranitidine , Delayed-Action Preparations/chemistry , Excipients/chemistry , Starch/chemistry , Tablets/chemistry
5.
RSC Adv ; 13(36): 25029-25053, 2023 Aug 21.
Article in English | MEDLINE | ID: mdl-37614791

ABSTRACT

Solid oxide fuel cells (SOFCs) are highly efficient, low-emission, and fuel-flexible energy conversion devices. However, their commercialization has lagged due to the lack of long-term durability. Among several performance degradation mechanisms, cathode degradation and elemental inter-diffusion of the electrolyte and cathode has been identified as the predominant factors. In the most common SOFC systems, a cobalt-based perovskite material is used, for example LSC or LSCF. These cobalt-based materials offer mixed conductivity and higher concentration of oxygen vacancies as compared to LSM at lower operating temperature leading to favorable reduction kinetics. However, the presence of cobalt results in higher cost, higher thermal expansion co-efficient (TEC) mismatch and most importantly leads to rapid degradation. Various elements like strontium, cobalt, cerium, chromium, or zirconium accumulate or deposit at the electrode-electrolyte interface, which results in sluggish reaction kinetics of the oxygen reduction reaction (ORR). These elements react to form secondary phases that have lower ionic and electronic conductivity, cover active reaction sites, and eventually lead to cell and system deterioration. Over the past decade, several studies have focused on preventative and protective measures to prolong SOFC lifetime which includes novel fabrication techniques, introduction of new layers, addition of thin films to block the cation transport. Such efforts to prevent the formation of insulating phases and decomposition of the cathode have resulted in a remarkable improvement in long-term stability. In this review paper, current research on leading mechanisms responsible for the degradation of cobaltite cathode of solid oxide fuel cell has been summarized and durability improvement strategies of cobalt-based SOFC cathodes have been discussed.

6.
RSC Adv ; 13(32): 22017-22028, 2023 Jul 19.
Article in English | MEDLINE | ID: mdl-37483669

ABSTRACT

Metal sulfides and 2D materials are the propitious candidates for numerous electrochemical applications, due to their superior conductivity and ample active sites. Herein, CuS nanoparticles were fabricated on 2D greener HF-free Cl-terminated MXene (Ti3C2Cl2) sheets by the hydrothermal process as a proficient electrocatalyst for the hydrogen evolution reaction (HER) and overall water splitting. CuS/Ti3C2Cl2 showed an overpotential of 163 mV and a Tafel slope of 77 mV dec-1 at 10 mA cm-2 for the HER. In the case of the OER, CuS/Ti3C2Cl2 exhibited an overpotential of 334 mV at 50 mA cm-2 and a Tafel slope of 42 mV dec-1. Moreover, the assembled CuS/Ti3C2Cl2||CuS/Ti3C2Cl2 electrolyzer delivered current density of 20 mA cm-2 at 1.87 V for overall water splitting. The CuS/Ti3C2Cl2 electrocatalyst showed excellent stability to retain 96% of its initial value for about 48 hours at 100 mA cm-2 current density. The synthesis of CuS/Ti3C2Cl2 enriches the applications of MXene/metal sulfides in efficient bifunctional electrocatalysis for alkaline water splitting.

7.
Chemosphere ; 326: 138448, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36940825

ABSTRACT

The substantial quantity of Cr(VI) contaminants in the aqueous atmosphere is a major environmental fear that cannot be overlooked. For the first time, MXene and chitosan-coated polyurethane foam have been employed for wastewater treatment, including heavy metal ions (Cr (VI)) through a fixed-bed column study. It is also the most inexpensive, lightweight, and globally friendly material tested. The Mxene and chitosan-coated polyurethane foam hybrid materials were thoroughly investigated using FTIR (Fourier transform infrared), SEM (scanning electron microscope), XPS (X-ray photoelectron spectroscopy) and XRD (X-ray diffraction). The presence of the rough surface and the pore creation in the Mxene- MX3@CS3@PUF should rise its surface area, which is useful to interact the surface-active assembly of MX3@CS3@PUF and the Cr(VI) contaminations in the aqueous solution. With the help of the ion exchange mechanism and electrostatic contact, negatively charged MXene hexavalent ions were being adsorbed on the surface. MXene and chitosan have been coated on PUF foam in the form of three different layers, which shows the highest adsorption capacity, where up to ∼70% Cr (VI) was removed in the first 10 min and more than 60% elimination after 3 h when the metal ion concentration was 20 ppm. The electrostatic interaction between the negative charge MXene and the positive charge chitosan on the surface of PUF, which was absent in MX@PUF, is accountable for the high removal efficiency. This was done through a sequence of fixed-bed column studies, which took place in the continuous flowing of wastewater.


Subject(s)
Chitosan , Water Pollutants, Chemical , Wastewater , Chitosan/chemistry , Water Pollutants, Chemical/analysis , Chromium/chemistry , Water/chemistry , Ions , Adsorption , Hydrogen-Ion Concentration , Kinetics , Spectroscopy, Fourier Transform Infrared
9.
RSC Adv ; 12(54): 35350-35357, 2022 Dec 06.
Article in English | MEDLINE | ID: mdl-36540254

ABSTRACT

Longer silver nanowires (AgNWs) > 50 µm and even 90 µm in length have been produced via a polyol method by just changing the stirring speed at a temperature of 130 °C. As-synthesized longer AgNWs are further utilized to construct transparent conductive AgNWs films by a facile drop-casting technique that attained a sheet resistance of 14.5 Ω sq-1 and transmittance over 85%, which is higher than ITO film. The use of a AgNWs/TiO2 hybrid electrode decreases the sheet resistance to 8.3 Ω sq-1, which is attributed to the enhancement of connections between AgNWs by filling the empty spaces between nanowires and TiO2 nanoparticles. Transparent perovskite solar cells (PSCs) on the basis of these AgNWs and AgNWs/TiO2 hybrid top electrodes were made and examined. Due to the light scattering nature of TiO2 nanoparticles, optical transmittance of the AgNWs/TiO2 hybrid electrode enhances to some extent after the coating of a TiO2 layer. Both cell efficiencies and stability of the PSCs are enhanced by using the AgNWs/TiO2 top electrode. A power conversion efficiency (PCE) of 10.65% was attained for perovskite devices based on only the AgNW electrode with a sheet resistance of 14.5 Ω sq-1. A PCE of 14.53% was achieved after coating with TiO2 nanoparticles, indicating the layer effect of TiO2 coating.

10.
Nanomaterials (Basel) ; 12(16)2022 Aug 22.
Article in English | MEDLINE | ID: mdl-36014753

ABSTRACT

In this study, a honeycomb-like porous-structured nickel-iron-cobalt layered double hydroxide/Ti3C2Tx (NiFeCo-LDH@MXene) composite was successfully fabricated on a three-dimensional nickel foam using a simple hydrothermal approach. Owing to their distinguishable characteristics, the fabricated honeycomb porous-structured NiFeCo-LDH@MXene composites exhibited outstanding bifunctional electrocatalytic activity for pair hydrogen and oxygen evolution reactions in alkaline medium. The developed NiFeCo-LDH@MXene electrocatalyst required low overpotentials of 130 and 34 mV to attain a current density of 10 mA cm-2 for OER and HER, respectively. Furthermore, an assembled NiFeCo-LDH@MXene‖NiFeCo-LDH@MXene device exhibited a cell voltage of 1.41 V for overall water splitting with a robust firmness for over 24 h to reach 10 mA cm-2 current density, signifying outstanding performance for water splitting reactions. These results demonstrated the promising potential of the designed 3D porous NiFeCo-LDH@MXene sheets as outstanding candidates to replace future green energy conversion devices.

11.
ACS Omega ; 7(24): 20556-20568, 2022 Jun 21.
Article in English | MEDLINE | ID: mdl-35755385

ABSTRACT

The ultimate goal of this research was to produce a cold galvanizing compound (CGC) at reduced pigment volume concentration (PVC) to protect metallic structures from corrosion attacks. The influence of partial replacement of Zn by nanolayered graphene (NGr) and red iron oxide (Fe2O3) nanoparticles on the electrochemical, morphological, rheological, and mechanical properties of CGCs was investigated. Electrochemical impedance spectroscopy (EIS) was used to investigate the electrochemical nature of coatings. The EIS results revealed that the partial replacement of Zn by NGr and Fe2O3 nanoparticles enhanced the cathodic protection at reduced PVC (4:1) by improving the electrical contact between the Zn particles and the metal substrate. The Tafel scan was conducted to support the cathodic behavior of the coatings. It was found that the sample formulated solely with Zn at PVC 4:1 was dominated in physical barrier characteristics over cathodic protection. By increasing the concentration of NGr in the formulation, the corrosion potential shifted toward a more negative side, and the coating with 1.5% NGr showed the highest galvanic action at reduced PVC. Field-emission scanning electron microscopy confirmed the interconnected network of conducting particles. The coating without NGr and Fe2O3 at PVC 4:1 showed significant gaps between the Zn particles. The novelty was evidenced when micrographs showed the consistent distribution of NGr and Fe2O3 nanoparticles all over the surface, which acted as a bridge between spherical Zn particles and provided cathodic protection at a reduced PVC. The layered structure of graphene also improved the physical shielding effect of the coatings, which limited the diffusion of electrolytes and corrosion products (oxides/hydroxides) into the coatings, which was reflected by the salt spray test. The rheological properties of coatings were studied in continuous ramp, peak hold step, temperature ramp, and frequency sweep oscillation experiments. All the coatings showed good liquid/fluid properties. The coatings having less PVC displayed better flow behavior during the application due to the less frictional forces in the internal structure. All the coatings showed excellent adhesion but had different strength values. In NGr/Fe2O3-modified coatings, the strength increased from 7.14 to 14.12 Mpa at reduced PVC. The addition of NGr provided an additional chemical bonding (galvanic action) to steel, which supported the physical adhesion and increased the overall adhesion strength. A real-time scratch resistance assessment showed that all the coatings had good scratch resistance due to the solid interconnection between Zn, NGr, and Fe2O3 particles.

12.
Mikrochim Acta ; 189(2): 64, 2022 01 17.
Article in English | MEDLINE | ID: mdl-35038033

ABSTRACT

Development of MXene (Ti3C2Cl2)-based sensing platforms by exploiting their inherent active electrochemistry is highly challenging due to their characteristic poor stability in air and water. Herein, we report a cost-effective methodology to deposit MXene on a conductive graphitic pencil electrode (GPE). MXenes can provide active surface area due to their clever morphology of accordion-like sheets; however, the disposition to stack together limits their potential applications. A task-specific ionic liquid (1-methyl imidazolium acetate) is utilized as a multiplex host material to engineer MXene interface via π-π interactions as well as to act as a selective binding site for biomolecules. The resulting IL-MXene/GPE interface proved to be a highly stable interface owing to good interactions between MXene and IL that inhibited electrode leaching and boosted electron transfer at the electrode-electrolyte interface. It resulted in robust dopamine (DA) oxidation with amplified faradaic response and enhanced sensitivity (9.61 µA µM-1 cm-2) for DA detection. This fabricated sensor demonstrated large linear range (10 µM - 2000 µM), low detection limit (702 nM), high reproducibility, and good selectivity. We anticipate that such platform will pave the way for the development of stable and economically viable MXene-based sensors without sacrificing their inherent properties. Scheme 1 Schematic illustration of the IL-MXene/GPE fabrication and oxidative process towards non-enzymatic dopamine sensor.


Subject(s)
Biosensing Techniques , Dopamine , Electrochemical Techniques , Ionic Liquids , Titanium , Biosensing Techniques/instrumentation , Biosensing Techniques/methods , Dopamine/chemistry , Electrochemical Techniques/instrumentation , Electrochemical Techniques/methods , Ionic Liquids/chemistry , Titanium/chemistry
13.
Talanta ; 239: 123109, 2022 Mar 01.
Article in English | MEDLINE | ID: mdl-34864531

ABSTRACT

With each passing year, the agriculture and wood processing industries generate increasingly high tonnages of biomass waste, which instead of being burned or left to accumulate should be utilized more sustainably. In parallel, advances in green technology have encouraged large companies and nations to begin using eco-friendly materials, including eco-friendly emulsifiers, which are used in various industries and in bio-based materials. The emulsion-conducive properties of lignocellulosic materials such as cellulose, hemicellulose, and lignin, the building blocks of plant and wood structures, have demonstrated a particular ability to alter the landscape of emulsion technology. Beyond that, the further modification of their structure may improve emulsion stability, which often determines the performance of emulsions. Considering those trends, this review examines the performance of lignocellulosic materials after modification according to their stability, droplet size, and distribution by size, all of which suggest their outstanding potential as materials for emulsifying agents.


Subject(s)
Emulsifying Agents , Lignin , Biomass , Cellulose
14.
Polymers (Basel) ; 13(19)2021 Oct 07.
Article in English | MEDLINE | ID: mdl-34641251

ABSTRACT

This study depicts the investigations of the effect of composition of aromatic polyester polyol produced from terephthalic acid (TPA) and different concentrations of mono ethylene glycol (mEG) as a chain extender on the mechanical properties of polyurethane (PU) elastomer. Aromatic polyester polyols are prepared via the poly-esterification of adipic acid, terephthalic acid, catalyst, and mono ethylene glycol; while a polyurethane elastomer is formulated via the pre-polymerization of polyol with pure monomeric Methylene diphenyl diisocyanate (MDI.) Mechanical properties of polyurethane elastomers are examined, such as hardness via shore A hardness, apparent density via ASTM (American Society for Testing and Materials) D1622-08, and abrasion wear resistance via a Deutches Institut fur Normung (DIN) abrasion wear resistance tester. Structural properties are investigated through Fourier-transform infrared spectroscopy (FTIR) analysis. Results reveal that the shore A hardness of the PU elastomer increases with an increasing concentration of mEG from 4g to 12g. Nevertheless, the elastomer's density depicts a reduction with an increasing extender content. The abrasion wear resistance of polyurethane, however, increases with an increasing concentration of glycol. A structural analysis through FTIR confirms the formation of polyurethane elastomer through the characteristic peaks demonstrated.

15.
ACS Omega ; 6(33): 21316-21326, 2021 Aug 24.
Article in English | MEDLINE | ID: mdl-34471736

ABSTRACT

It is extremely prudent and highly challenging to design a greener bifunctional electrocatalyst that shows effective electrocatalytic activity and high stability toward electrochemical water splitting. As several hundred tons of catalysts are annually deactivated by deposition of carbon, herein, we came up with a strategy to reutilize spent methane reforming catalysts that were deactivated by the formation of graphitic carbon (GC) and carbon nanofibers (CNF). An electrocatalyst was successfully synthesized by in situ deposition of noble metal-free MoS2 over spent catalysts via a hydrothermal method that showed exceptional performance regarding the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER). At 25 mA cm-2, phenomenal OER overpotentials (η25) of 128 and 154 mV and modest HER overpotentials of 186 and 207 mV were achieved for MoS2@CNF and MoS2@GC, respectively. Moreover, OER Tafel slopes of 41 and 71 mV dec-1 and HER Tafel slopes of 99 and 107 mV dec-1 were obtained for MoS2@CNF and MoS2@GC, respectively. Furthermore, the synthesized catalysts exhibited good long-term durability for about 18 h at 100 µA cm-2 with unnoticeable changes in the linear sweep voltammetry (LSV) curve of the HER after 1000 cycles. The carbon on the spent catalyst increased the conductivity, while MoS2 enhanced the electrocatalytic activity; hence, the synergistic effect of both materials resulted in enhanced electrocatalysts for overall water splitting. This work of synthesizing enhanced nanostructured electrocatalysts with minimal usage of inexpensive MoS2 gives a rationale for engineering potent greener electrocatalysts.

16.
Expert Syst Appl ; 185: 115695, 2021 Dec 15.
Article in English | MEDLINE | ID: mdl-34400854

ABSTRACT

During the current global public health emergency caused by novel coronavirus disease 19 (COVID-19), researchers and medical experts started working day and night to search for new technologies to mitigate the COVID-19 pandemic. Recent studies have shown that artificial intelligence (AI) has been successfully employed in the health sector for various healthcare procedures. This study comprehensively reviewed the research and development on state-of-the-art applications of artificial intelligence for combating the COVID-19 pandemic. In the process of literature retrieval, the relevant literature from citation databases including ScienceDirect, Google Scholar, and Preprints from arXiv, medRxiv, and bioRxiv was selected. Recent advances in the field of AI-based technologies are critically reviewed and summarized. Various challenges associated with the use of these technologies are highlighted and based on updated studies and critical analysis, research gaps and future recommendations are identified and discussed. The comparison between various machine learning (ML) and deep learning (DL) methods, the dominant AI-based technique, mostly used ML and DL methods for COVID-19 detection, diagnosis, screening, classification, drug repurposing, prediction, and forecasting, and insights about where the current research is heading are highlighted. Recent research and development in the field of artificial intelligence has greatly improved the COVID-19 screening, diagnostics, and prediction and results in better scale-up, timely response, most reliable, and efficient outcomes, and sometimes outperforms humans in certain healthcare tasks. This review article will help researchers, healthcare institutes and organizations, government officials, and policymakers with new insights into how AI can control the COVID-19 pandemic and drive more research and studies for mitigating the COVID-19 outbreak.

17.
Mikrochim Acta ; 188(7): 230, 2021 06 12.
Article in English | MEDLINE | ID: mdl-34117945

ABSTRACT

The synthesis of novel architecture comprising perylene diimide (PDI)-MXene (Ti3C2TX)-integrated graphitic pencil electrode for electrochemical detection of dopamine (DA) is reported. The good electron passage between PDI-MXene resulted in an unprecedented nano-adduct bearing enhanced electrocatalytic activity with low-energy electronic transitions. The anionic groups of PDI corroborated enhanced active surface area for selective binding and robust oxidation of DA, thereby decreasing the applied potential. Meanwhile, the MXene layers acted as functional conducive support for PDI absorption via strong H-bonding. The considerable conductivity of MXene enhanced electron transportation thus increasing the sensitivity of sensing interface. The inclusively engineered nano-adduct resulted in robust DA oxidation with ultra-sensitivity (38.1 µAµM-1cm-2), and low detection limit (240 nM) at very low oxidation potential (-0.135 V). Moreover, it selectively signaled DA in the presence of physiological interferents with wide linearity (100-1000 µM). The developed transducing interface performed well in human serum samples with RSD (0.1 to 0.4%) and recovery (98.6 to 100.2%) corroborating the viability of the practical implementation of this integrated system. Graphical abstract Schematic illustration of the oxidative process involved on constructed sensing interface for the development of a non-enzymatic dopamine sensor.


Subject(s)
Dopamine/chemistry , Electrochemical Techniques/methods , Electrodes/standards , Imides/chemistry , Perylene/analogs & derivatives , Graphite , Humans , Perylene/chemistry
18.
Int J Biol Macromol ; 164: 4370-4380, 2020 Dec 01.
Article in English | MEDLINE | ID: mdl-32926902

ABSTRACT

Controlled drug delivery is a prime stratagem for minimizing both the frequency of therapeutic administration as well as systematic side effects with high drug content. One of the extensively studied approaches for controlling medicament delivery is the encapsulation of drug within polymer chains which sluggish the release on the basis of its crosslinked network. Recent advances in biomedical field have led to the fabrication of chitosan (CS) based biocompatible and biodegradable hydrogels for controlled delivery of encapsulated drug. In this study, CS-PVP based hydrogels are fabricated by varying the concentration of 3-glycidyloxypropyl trimethoxysilane (GPTMS) via solution casting technique. Swelling indices of prepared hydrogel samples were determined in different media including distilled water, different pH and electrolyte solutions. FTIR, TGA and WAXRD are conducted to evaluate the structural, thermal and crystalline properties of prepared hydrogels, respectively. Porosity (71%), hydrophilicity (55°) and mechanical properties (97.56 MPa of UTS and 85.23% E%) were investigated for the fabricated samples. Extensively in vitro biodegradation, antimicrobial performance and cytotoxicity were evaluated for these hydrogels. The drug release analysis was carried out to examine the release response of encapsulated iodopovidone at physiological conditions. These results tender a strategy for the design of structural hydrogel with different crosslinking mechanism like physical and covalent interactions. These insights obviate the demand for encapsulation and offer promising and translatable strategies for more effective release of drugs.


Subject(s)
Chitosan/chemistry , Drug Carriers/chemistry , Drug Delivery Systems , Hydrogels/chemistry , Povidone-Iodine/administration & dosage , Cross-Linking Reagents/chemistry , Delayed-Action Preparations , Drug Liberation , Electrolytes , Humans , Hydrogen-Ion Concentration , Hydrophobic and Hydrophilic Interactions , Porosity , X-Ray Diffraction
19.
Int J Biol Macromol ; 162: 175-187, 2020 Nov 01.
Article in English | MEDLINE | ID: mdl-32562726

ABSTRACT

Inflammation is a key challenge in the treatment of chronic diseases. Spurred by topical advancement in polymer chemistry and drug delivery, hydrogels that release a drug in temporal, spatial and dosage controlled fashion have been trendy. This research focused on the fabrication of hydrogels with controlled drug release properties to control inflammation. Chitosan and polyvinyl pyrrolidone were used as base polymers and crosslinked with epichlorohydrin to form hydrogel films by solution casting technique. Prepared hydrogels were analyzed by swelling analysis in deionized water, buffer and electrolyte solutions and gel fraction. Functional groups confirmation and development of new covalent and hydrogen bonds, thermal stability (28.49%) and crystallinity were evaluated by FTIR, TGA and WAXRD, respectively. Rheological properties including gel strength and yield stress, elasticity (2309 MPa), porosity (75%) and hydrophilicity (73°) of prepared hydrogels were also evaluated. In vitro studies confirmed that prepared hydrogels have good biodegradability, excellent antimicrobial property and admirable cytotoxicity. Drug release profile (87.56% in 130 min) along with the drug encapsulation efficiency (84%) of prepared hydrogels was also studied. These results paved the path towards the development of hydrogels that can release the drugs with desired temporal patterns.


Subject(s)
Artemia/drug effects , Chitosan/chemistry , Diclofenac/chemistry , Drug Delivery Systems/methods , Escherichia coli/drug effects , Hydrogels/chemistry , Animals , Cross-Linking Reagents/chemistry , Delayed-Action Preparations/chemistry , Drug Carriers/chemistry , Drug Liberation , Elasticity , Epichlorohydrin/chemistry , Hydrogels/chemical synthesis , Hydrogen Bonding , Hydrophobic and Hydrophilic Interactions , Inflammation , Microscopy, Electron, Scanning , Porosity , Povidone/chemistry , Rheology , Spectroscopy, Fourier Transform Infrared , Water/chemistry , X-Ray Diffraction
20.
Dalton Trans ; 48(31): 11803-11812, 2019 Aug 21.
Article in English | MEDLINE | ID: mdl-31304494

ABSTRACT

Industrial utilization of nuclear resources greatly depends on the effective treatment of nuclear waste. The efficient removal of radioactive nuclides from liquid effluents by using different adsorbents has thus become crucial. Herein, for the first time, two-dimensional transition metal carbides (MXenes) are investigated as scavengers of cesium (Cs+) from contaminated water. Due to the combined advantages of the layered structure and the presence of heterogeneous sites (hydroxyl, oxygen and fluorine groups), the adsorbent reached the steady state within 1 min with the maximum Cs+ adsorption capacity of 25.4 mg g-1 at room temperature. The kinetics studies of the Cs+ scavenging process demonstrated that the adsorption of Cs+ followed the pseudo-second-order model whereas the adsorption equilibrium data obeyed the Freundlich model. Thermodynamic studies revealed that the adsorption process was endothermic. The adsorbent showed an excellent Cs+ removal efficiency in neutral to slightly alkaline solutions. Moreover, it can retain Cs+ even in the presence of a high concentration of competing cations (Li+, Na+, K+, Mg2+ and Sr2+). The Cs+ loaded adsorbent was regenerated with a 0.2 M HCl solution and reused at least five times for over 91% removal of contaminants.

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