Recent Advancements in Green Synthesis of Nanoparticles for improvement of bioactivities: a Review

2021 ◽  
Vol 22 ◽  
Author(s):  
Vinay Deep Punetha ◽  
Sunil Dhali ◽  
Anita Rana ◽  
Neha Karki ◽  
Himani Tiwari ◽  
...  
Keyword(s):  
Natural Products ◽  
Nano Particles ◽  
Nano Materials ◽  
Plant Metabolites ◽  
Plant Materials ◽  
Environment Friendly ◽  
Synthesis Of Nanoparticles ◽  
New Horizons ◽  
Metal Nano Particles

: Natural products have widely been used in applications ranging from antibacterial, antiviral, antifungal and various other medicinal applications. Use of these natural products was recognized way before the establishment of basic chemistry behind the disease and the chemistry of plant metabolites. After the establishment of plant chemistry various new horizons evolved, and application of the natural products breached the orthodox limitations. In one such interdisciplinary area, use of plant materials in the synthesis of nano particles (NPs) has exponentially emerged. This advancement has offered various environment friendly methods where hazardous chemicals are completely replaced by natural products in the sophisticated and hectic synthesis processes. This review is an attempt to understand the mechanism of metal nano particles synthesis using plant materials. It includes details on the role of plant’s secondary metabolites in the synthesis of nano particles including the mechanism of action. In addition, use of these nano materials has widely been discussed along with the possible mechanism behind their antimicrobial and catalytic action.

Electrowetting of Nanofluids Containing Silver Nanoparticles

2008 ◽  
Author(s):  
Leonard Laroque ◽  
Abhishek Jain ◽  
Tie Wang ◽  
Karthik Chinnathambi ◽  
Ganapathiraman Ramanath ◽  
...  
Keyword(s):  
Contact Angle ◽  
Nano Particles ◽  
Voltage Range ◽  
Electrowetting On Dielectric ◽  
Angle Change ◽  
Wide Range ◽  
Fundamental Understanding ◽  
Electro Wetting ◽  
Metal Nano Particles

Application of voltage across a liquid-dielectric interface resulting in the change of fluid contact angle is known as electrowetting on dielectric (EWOD) effect [1]. EWOD actuation is one of the most preferred techniques to move liquid at microscale due to relatively low voltages, low currents and power consumption requirements, and the absence of electrolysis. Our recent work has shown that nanofluids containing semiconductor nanoparticles exhibit a very strong EWOD effect [2, 3]. In particular, in the tested voltage range of 0 to 60 V, nanofluids loaded with molecularly-capped bismuth telluride nanoparticles show enhanced stability and increased actuation range of contact angle change. Developing a fundamental understanding of the role of nanostructure inclusions in controlling and potentially enhancing the EWOD effect would pave the way for the efficient use of EWOD with nanofluids in a wide range or microfluidic applications. Here we extend the studies on the EWOD behavior of nanofluids, to a system containing noble metal nano particles. In this abstract we report the preliminary results of the electro-wetting studies on nanofluids containing silver nano particles.

scholarly journals On the role of N-methylmorpholine-N-oxide (NMMO) in the generation of elemental transition metal precipitates in cellulosic materials

Cellulose ◽  
2021 ◽  
Author(s):  
Thomas Rosenau ◽  
Antje Potthast ◽  
Hubert Hettegger ◽  
Markus Bacher ◽  
Martina Opietnik ◽  
...  
Keyword(s):  
Transition Metal ◽  
Chloride Ions ◽  
Nano Particles ◽  
Reaction Conditions ◽  
Cellulosic Materials ◽  
Chemical Systems ◽  
Particle Generation ◽  
Transition Metal Salts ◽  
Metal Nano Particles

AbstractSeveral literature reports describe the role of aqueous solutions of N-methylmorpholine-N-oxide monohydrate (NMMO) as a suitable medium for the generation of transition metal (nano)particles in or on cellulosic materials and further elaborate its role as a co-reactant of the transition metal salts that are reduced to the elemental metal. However, this would assign NMMO the role of a reductant, which is in contradiction of its obvious oxidative nature. In the present study, the exemplary cases of silver, gold, and platinum salts as the precursors of the respective metal (nano)particles in aqueous NMMO/cellulose mixtures were investigated. Naturally, NMMO did not act as a reducing agent in any case—this role was taken over by the frequently used NMMO stabilizer propyl gallate, or by cellulose itself, into which carbonyl and carboxyl groups were introduced. Also, hypochlorite—produced intermediately from chloride ions and subsequently undergoing disproportionation into chloride and chlorate—or transient N-methylene(morpholinium) ions generated from NMMO, which are in turn oxidized to formyl morpholide, can act as the corresponding reductants while the metal ions are reduced, depending on the reaction conditions. Apart from providing interesting mechanistic insights, the study points to the importance of a precise description of the composition of the chemical systems used, as well as the importance of seemingly inert auxiliaries, which turned out to be essential co-reactants in the metal (nano)particle generation. Graphic abstract

Plant-Mediated Synthesis of Iron Oxide Nanoparticles and Evaluation of the Antimicrobial Activity: A Review

2020 ◽  
Vol 17 ◽  
Author(s):  
Abderrhmane Bouafia ◽  
Salah Eddine Laouini
Keyword(s):  
Natural Products ◽  
Green Synthesis ◽  
Pathogenic Bacteria ◽  
State Of The Art ◽  
Environment Friendly ◽  
Capping Agents ◽  
Synthesis Of Nanoparticles ◽  
Wide Range ◽  
Important Challenge ◽  
Made In

: In this review, we examine ‘greener’ routes to nanoparticles of iron oxides, in the recent years; nanotechnology has emerged as a state-of-the-art and cutting edge technology with multifarious applications in a wide array of fields. Natural products or extracted from natural products. Such as different plant extracts, have been used as reductants, and as capping agents during synthesis. A very easy, efficient and environment-friendly protocol was developed to synthesize green nanoparticles (NPs) with an aqueous extract of various plant, phenolic compounds extracted from plants play a major role as a non-toxic reducing and capping agents for nanoparticle. Nanoparticles and their compounds are known to exert a strong inhibitory and microbial activity on bacteria, viruses, and fungi. In today's world, because of the epidemic of infectious diseases caused by different pathogenic bacteria and the development of antibiotic resistance. Green synthesis, characterization, and application of nanoparticles (NPs) are becoming an important challenge in nanotechnology. Green synthesis of nanoparticles is made in large quantities worldwide for a wide range of applications. This technique is very safe and environmentally friendly.

Pharmacologic Role of Vitamin D Natural Products

2014 ◽  
Vol 12 (2) ◽  
pp. 278-285 ◽  
Author(s):  
Pablo Urena-Torres ◽  
Jean Souberbielle
Keyword(s):  
Vitamin D ◽  
Natural Products

Recent Progress in the Analysis of Captopril Using Electrochemical Methods: A Review

2019 ◽  
Vol 15 (3) ◽  
pp. 198-206 ◽  
Author(s):  
Sarfaraz Ahmed Mahesar ◽  
Saeed Ahmed Lakho ◽  
Syed Tufail Hussain Sherazi ◽  
Hamid Ali Kazi ◽  
Kamran Ahmed Abro ◽  
...  
Keyword(s):  
Enzyme Inhibitor ◽  
Modified Electrodes ◽  
High Sensitivity ◽  
Pharmaceutical Formulations ◽  
Inorganic Materials ◽  
Electrochemical Methods ◽  
Nano Particles ◽  
Moderate Heart Failure ◽  
Analytical Instrumentation

Background: Captopril is the synthetic dipeptide used as an angiotensin converting enzyme inhibitor. Captopril is used to treat hypertension as well as for the treatment of moderate heart failure. Analytical instrumentation and methodology plays an important role in pharmaceutical analysis. Methods: This review presents some important applications of electrochemical modes used for the analysis of captopril. So far captopril has been analyzed by using different bare and modified working electrodes with a variety of modifiers from organic and inorganic materials to various types of nano particles/materials. Results: This paper presents some of the methods which have been published in the last few years i.e. from 2003 to 2016. This review highlights the role of the analytical instrumentation, particularly electrochemical methods in assessing captopril using various working electrodes. Conclusion: A large number of studies on voltammetry noted by means of various bare and modified electrodes. Among all of the published voltammetric methods, DPV, SWV, CV and miscellaneous modes were trendy techniques used to analyze captopril in pharmaceutical formulations as well as biological samples. Electrodes modified with nanomaterials are promising sensing tools as this showed high sensitivity, good accuracy with precision as well as selectivity. In comparison to chromatographic methods, the main advantages of electrochemical methods are its cheaper instrumentation, lower detection limit and minimal or no sample preparation.

γ-Valerolactone-Introduced Controlled-Isomerization of Glucose for Lactic Acid Production over Sn-Beta Catalyst

2021 ◽  
Author(s):  
Xinpeng Zhao ◽  
Zhimin Zhou ◽  
hu luo ◽  
Yanfei Zhang ◽  
Wang Liu ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Lactic Acid ◽  
Dft Calculations ◽  
Acid Production ◽  
Density Functional ◽  
Lactic Acid Production ◽  
Hydrothermal Conversion ◽  
Functional Theory ◽  
Environment Friendly

Combined experiments and density functional theory (DFT) calculations provided insights into the role of the environment-friendly γ-valerolactone (GVL) as a solvent in the hydrothermal conversion of glucose into lactic acid...

scholarly journals Oxidation of Terpenoids to Achieve High-Value Flavor and Fragrances—Questioning Microalgae Oxidative Capabilities in the Biotransformation of the Sesquiterpene Valencene and of Selected Natural Apocarotenoids

Chemistry ◽  
2021 ◽  
Vol 3 (3) ◽  
pp. 821-830
Author(s):  
Davide De Simeis ◽  
Stefano Serra ◽  
Alessandro Di Fonzo ◽  
Francesco Secundo
Keyword(s):  
Experimental Data ◽  
Natural Products ◽  
Aqueous Medium ◽  
Photochemical Reaction ◽  
Substrate Oxidation ◽  
Market Size ◽  
Chlorella Sp ◽  
General Opinion ◽  
Natural Way

Natural flavor and fragrance market size is expected to grow steadily due to the rising consumer demand of natural ingredients. This market request is guided by the general opinion that the production of natural compounds leads to a reduction of pollution, with inherent advantages for the environment and people’s health. The biotransformation reactions have gained high relevance in the production of natural products. In this context, few pieces of research have described the role of microalgae in the oxidation of terpenoids. In this present study, we questioned the role of microalgal based oxidation in the synthesis of high-value flavors and fragrances. This study investigated the role of three different microalgae strains, Chlorella sp. (211.8b and 211.8p) and Chlorococcum sp. (JB3), in the oxidation of different terpenoid substrates: α-ionone, β-ionone, theaspirane and valencene. Unfortunately, the experimental data showed that the microalgal strains used are not responsible for the substrate oxidation. In fact, our experiments demonstrate that the transformation of the four starting compounds is a photochemical reaction that involves the oxygen as oxidant. Even though these findings cast a shadow on the use of these microorganisms for an industrial purpose, they open a new possible strategy to easily obtain nootkatone in a natural way by just using an aqueous medium, oxygen and light.

Role of CEUS in Vascular Pathology

2021 ◽  
Author(s):  
Vito Cantisani ◽  
Nicola Di Leo ◽  
Emanuele David ◽  
Dirk-André Clevert
Keyword(s):  
Research Field ◽  
Arterial System ◽  
Qualitative Assessment ◽  
Vascular Pathology ◽  
New Horizons ◽  
Contrast Enhanced ◽  
Inflammatory Infiltrates ◽  
Time Evaluation

AbstractIn recent years, the implementation of contrast-enhanced ultrasound (CEUS) in clinical practice has opened new horizons in the arterial pathologies research field, since this technique is able to supply new sets of data that can be crucial in patient management. The main applications of CEUS in the arterial system are the detection, characterization, and follow-up of carotid plaques and endoleaks after EVAR. Other situations in which CEUS was demonstrated to be a useful tool are large vessel vasculitis, dissections, and untreated aneurysms. In carotid atherosclerosis CEUS is not only able to acquire quantitative data about stenosis but also to perform a qualitative assessment of the plaque. The most important plaque features that CEUS is able to depict are ulceration, neovascularization, and the presence of inflammatory infiltrates. All of these factors contribute to plaque vulnerability. Thus, CEUS is crucial in order to allow better risk stratification and management of patients. In follow-up after EVAR, CEUS shows sensitivity and specificity values similar to CTA while ensuring several advantages, such as lower cost and the absence of ionizing radiation and nephrotoxic agents. Moreover, CEUS is able to offer real-time evaluation of endoleaks and thus is a useful tool in cases that are ambiguous on CTA. Most limitations are patient-related and are the same as in all other ultrasound techniques, such as high BMI and meteorism.

Sign in / Sign up

Export Citation Format

Share Document