MRI Relaxivity Changes of the Magnetic Nanoparticles Induced by Different Amino Acid Coatings

In this study, we analysed the physico-chemical properties of positively charged magnetic fluids consisting of magnetic nanoparticles (MNPs) functionalised by different amino acids (AAs): glycine (Gly), lysine (Lys) and tryptophan (Trp), and the influence of AA–MNP complexes on the MRI relaxivity. We found that the AA coating affects the size of dispersed particles and isoelectric point, as well as the zeta potential of AA–MNPs differently, depending on the AA selected. Moreover, we showed that a change in hydrodynamic diameter results in a change to the relaxivity of AA–MNP complexes. On the one hand, we observed a decrease in the relaxivity values, r1 and r2, with an increase in hydrodynamic diameter (the relaxivity of r1 and r2 were comparable with commercially available contrast agents); on the other hand, we observed an increase in r2* value with an increase in hydrodynamic size. These findings provide an interesting preliminary look at the impact of AA coating on the relaxivity properties of AA–MNP complexes, with a specific application in molecular contrast imaging originating from magnetic nanoparticles and magnetic resonance techniques.

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Magnetic Nanoparticles for Drug Delivery Applications

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2008.399 ◽

2008 ◽

Vol 8 (7) ◽

pp. 3247-3271 ◽

Cited By ~ 102

Author(s):

Mini Namdeo ◽

Sutanjay Saxena ◽

Rasika Tankhiwale ◽

M. Bajpai ◽

Y. M. Mohan ◽

...

Keyword(s):

Drug Delivery ◽

Magnetic Nanoparticles ◽

Biomedical Applications ◽

Chemical Properties ◽

Brain Targeting ◽

Resonance Imaging ◽

Contrast Imaging ◽

Physico Chemical ◽

Magnetic Resonance Imaging Contrast ◽

The Individual

In recent past magnetic nanoparticles have been explored for a number of biomedical applications due to their superparamagnetic moment with high magnetic saturation value. For these biomedical applications, magnetic nanoparticles require being monodispersed so that the individual nanoparticle has almost identical physico-chemical properties for biodistribution, bioelimination and contrast imaging potential. Further, the surface functionalization/modification of magnetic nanoparticles ultimately facilitate the protein or DNA separation, detection and magnetic resonance imaging contrast, drug delivery and hyperthermia applications. The essential goal of this review is to evaluate the recent advances of magnetic nanoparticles for tumor, brain targeting and hyperthermia applications.

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The Impact of Filler Geometry on Polylactic Acid-Based Sustainable Polymer Composites

Molecules ◽

10.3390/molecules26010149 ◽

2020 ◽

Vol 26 (1) ◽

pp. 149

Author(s):

Karol Leluk ◽

Stanisław Frąckowiak ◽

Joanna Ludwiczak ◽

Tomasz Rydzkowski ◽

Vijay Kumar Thakur

Keyword(s):

Polymer Composites ◽

Polylactic Acid ◽

Matrix Material ◽

Chemical Properties ◽

Precipitated Calcium Carbonate ◽

Cellulose Fibres ◽

Shape Factors ◽

Pure Cellulose ◽

Physico Chemical ◽

The Impact

Recently, biocomposites have emerged as materials of great interest to the scientists and industry around the globe. Among various polymers, polylactic acid (PLA) is a popular matrix material with high potential for advanced applications. Various particulate materials and nanoparticles have been used as the filler in PLA based matrix. One of the extensively studied filler is cellulose. However, cellulose fibres, due to their hydrophilic nature, are difficult to blend with a hydrophobic polymer matrix. This leads to agglomeration and creates voids, reducing the mechanical strength of the resulting composite. Moreover, the role of the various forms of pure cellulose and its particle shape factors has not been analyzed in most of the current literature. Therefore, in this work, materials of various shapes and shape factors were selected as fillers for the production of polymer composites using Polylactic acid as a matrix to fill this knowledge gap. In particular, pure cellulose fibres (three types with different elongation coefficient) and two mineral nanocomponents: precipitated calcium carbonate and montmorillonite were used. The composites were prepared by a melt blending process using two different levels of fillers: 5% and 30%. Then, the analysis of their thermomechanical and physico-chemical properties was carried out. The obtained results were presented graphically and discussed in terms of their shape and degree of filling.

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Simple Nanoparticles from the Assembly of Cationic Polymer and Antigen as Immunoadjuvants

Vaccines ◽

10.3390/vaccines8010105 ◽

2020 ◽

Vol 8 (1) ◽

pp. 105 ◽

Cited By ~ 5

Author(s):

Yunys Pérez-Betancourt ◽

Bianca de Carvalho Lins Fernandes Távora ◽

Mônica Colombini ◽

Eliana L. Faquim-Mauro ◽

Ana Maria Carmona-Ribeiro

Keyword(s):

Delayed Type Hypersensitivity ◽

Hydrodynamic Diameter ◽

Spherical Nanoparticles ◽

Diallyldimethylammonium Chloride ◽

The One ◽

Antigen Presenting ◽

Th 1 ◽

Positively Charged ◽

Stimulation Of

Since antigens are negatively charged, they combine well with positively charged adjuvants. Here, ovalbumin (OVA) (0.1 mg·mL−1) and poly (diallyldimethylammonium chloride) (PDDA) (0.01 mg·mL−1) yielded PDDA/OVA assemblies characterized by dynamic light scattering (DLS) and scanning electron microscopy (SEM) as spherical nanoparticles (NPs) of 170 ± 4 nm hydrodynamic diameter, 30 ± 2 mV of zeta-potential and 0.11 ± 0.01 of polydispersity. Mice immunization with the NPs elicited high OVA-specific IgG1 and low OVA-specific IgG2a production, indicating a Th-2 response. Delayed-type hypersensitivity reaction (DTH) was low and comparable to the one elicited by Al(OH)3/OVA, suggesting again a Th-2 response. PDDA advantages as an adjuvant were simplicity (a single-component adjuvant), low concentration needed (0.01 mg·mL−1 PDDA) combined with antigen yielding neglectable cytotoxicity, and high stability of PDDA/OVA dispersions. The NPs elicited much higher OVA-specific antibodies production than Al(OH)3/OVA. In vivo, the nano-metric size possibly assured antigen presentation by antigen-presenting cells (APC) at the lymph nodes, in contrast to the location of Al(OH)3/OVA microparticles at the site of injection for longer periods with stimulation of local dendritic cells. In the future, it will be interesting to evaluate combinations of the antigen with NPs carrying both PDDA and elicitors of the Th-1 response.

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Unveiling the Efficiency of Vermicompost Derived from Different Biowastes on Wheat (Triticum aestivum L.) Plant Growth and Soil Health

Agronomy ◽

10.3390/agronomy9120791 ◽

2019 ◽

Vol 9 (12) ◽

pp. 791 ◽

Cited By ~ 1

Author(s):

Zubair Aslam ◽

Safdar Bashir ◽

Waseem Hassan ◽

Korkmaz Bellitürk ◽

Niaz Ahmad ◽

...

Keyword(s):

Plant Growth ◽

Temporal Trends ◽

Soil Health ◽

Chemical Properties ◽

Test Plant ◽

Cow Dung ◽

Aphid Infestation ◽

Physico Chemical ◽

Chemical Attributes ◽

The Impact

The present study was conducted to explore the role of different types of vermicomposts (VCs) prepared from different substrates to improve soil health (physical and chemical properties) and wheat plant growth under field conditions. Different combinations of vermicompost prepared from different substrates (cow dung, paper waste, and rice straw) and inorganic fertilizers were applied in soil using wheat as a test plant. The impact of three different VCs on physico-chemical characteristics and nutrient availability in soil was evaluated to examine their efficacy in combination with chemical fertilizers. Temporal trends in vermicomposting treatments at various stages showed significant improvement in physico-chemical attributes of the VCs substrates. All the plant physiological attributes showed significant response where N:P:K 100:50:50 kg ha−1 + 10 t ha−1 cow dung vermicompost was applied. In addition, post-harvest analysis of soil not only revealed that different combinations of the vermicomposting treatments improved the soil health by improving the physico-chemical attributes of the soil. Conclusively, application of cow dung vermicompost along with recommended NPK not only improved crop yield, soil health, reduced insect (aphid) infestation but also fortified grains with Zn and Fe.

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IMPACT OF AGRO-ENVIRONMENTAL SYSTEMS ON SOIL EROSION PROCESSES AND SOIL PROPERTIES ON HILLY LANDSCAPE IN WESTERN LITHUANIA

Journal of Environmental Engineering and Landscape Management ◽

10.3846/16486897.2015.1054289 ◽

2015 ◽

Vol 24 (1) ◽

pp. 60-69 ◽

Cited By ~ 6

Author(s):

Gintaras JARAŠIŪNAS ◽

Irena KINDERIENĖ

Keyword(s):

Soil Erosion ◽

Soil Properties ◽

Soil Ph ◽

Soil Texture ◽

Sandy Loam ◽

Chemical Properties ◽

Available Phosphorus ◽

Erosion Processes ◽

Physico Chemical ◽

The Impact

The objective of this study was to evaluate the impact of different land use systems on soil erosion rates, surface evolution processes and physico-chemical properties on a moraine hilly topography in Lithuania. The soil of the experimental site is Bathihypogleyi – Eutric Albeluvisols (abe–gld–w) whose texture is a sandy loam. After a 27-year use of different land conservation systems, three critical slope segments (slightly eroded, active erosion and accumulation) were formed. Soil physical properties of the soil texture and particle sizes distribution were examined. Chemical properties analysed for were soil ph, available phosphorus (P) and potassium (K), soil organic carbon (SOC) and total nitrogen (N). We estimated the variation in thickness of the soil Ap horizon and soil physico-chemical properties prone to a sustained erosion process. During the study period (2010–2012) water erosion occurred under the grain– grass and grass–grain crop rotations, at rates of 1.38 and 0.11 m3 ha–1 yr–1, respectively. Soil exhumed due to erosion from elevated positions accumulated in the slope bottom. As a result, topographic transfiguration of hills and changes in soil properties occurred. However, the accumulation segments of slopes had significantly higher silt/clay ratios and SOC content. In the active erosion segments a lighter soil texture and lower soil ph were recorded. Only long-term grassland completely stopped soil erosion effects; therefore geomorphologic change and degradation of hills was estimated there as minimal.

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A study on Apple ber to identify the suitability of new product development

Plant Science Today ◽

10.14719/pst.2020.7.1.640 ◽

2020 ◽

Vol 7 (1) ◽

pp. 61-69

Author(s):

S Mathangi ◽

J P Maran

Keyword(s):

Product Development ◽

New Product Development ◽

New Products ◽

Chemical Properties ◽

New Product ◽

Proximate Analysis ◽

Physico Chemical ◽

The World ◽

The One ◽

Powdered Form

This study emphasis on the physico-chemical properties of a new ber variety (Apple ber) originated in Thailand and slowly emerging in many parts of the world. The analysis is done under two different conditions the one being controlled and second one is blanched. The analysis revealed that the controlled condition is superior in physico-chemical properties than the blanched one. Also, proximate analysis was carried out on the fruit and its powdered form. In this analysis also controlled condition parameters were ahead of blanched. New products were developed with the Apple ber powder.

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Evaluation of the Physico-Chemical Properties of Liposomes Assembled from Bioconjugates of Anisic Acid with Phosphatidylcholine

International Journal of Molecular Sciences ◽

10.3390/ijms222313146 ◽

2021 ◽

Vol 22 (23) ◽

pp. 13146

Author(s):

Hanna Pruchnik ◽

Anna Gliszczyńska ◽

Aleksandra Włoch

Keyword(s):

Phase Transition ◽

Lipid Bilayer ◽

Chemical Properties ◽

Main Phase ◽

Cancer Therapies ◽

Dependent Manner ◽

Scanning Calorimetry ◽

Physico Chemical ◽

Anisic Acid ◽

The Impact

The aim of this work was the evaluation of the physico-chemical properties of a new type of liposomes that are composed of DPPC and bioconjugates of anisic acid with phosphatidylcholine. In particular, the impact of modified anisic acid phospholipids on the thermotropic parameters of liposomes was determined, which is crucial for using them as potential carriers of active substances in cancer therapies. Their properties were determined using three biophysical methods, namely differential scanning calorimetry (DSC), steady-state fluorimetry and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR). Moreover, temperature studies of liposomes composed of DPPC and bioconjugates of anisic acid with phosphatidylcholine provided information about the phase transition, fluidity regarding chain order, hydration and dynamics. The DSC results show that the main phase transition peak for conjugates of anisic acid with phosphatidylcholine molecules was broadened and shifted to a lower temperature in a concentration- and structure-dependent manner. The ATR-FTIR results and the results of measurements conducted using fluorescent probes located at different regions in the lipid bilayer are in line with DSC. The results show that the new bioconjugates with phosphatidylcholine have a significant impact on the physico-chemical properties of a membrane and cause a decrease in the temperature of the main phase transition. The consequence of this is greater fluidity of the lipid bilayer.

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Interdisciplinary Projects Applied to Chemistry Lessons: Example of Chemistry Linked to Food Science

CHIMIA International Journal for Chemistry ◽

10.2533/chimia.2020.196 ◽

2020 ◽

Vol 74 (3) ◽

pp. 196-198

Author(s):

Lydie Moreau ◽

Véronique Breguet Mercier

Keyword(s):

Ascorbic Acid ◽

Network Formation ◽

Chemical Properties ◽

Working Environment ◽

Food Science ◽

Physico Chemical ◽

Interdisciplinary Projects ◽

The Impact ◽

Design Experiments ◽

Good Organization

An interdisciplinary project regarding the effect of ascorbic acid on bread dough's physico-chemical properties was proposed to bachelor students in chemistry and food sciences. Such an approach was proposed to develop both scientific and soft skills, in order to prepare students for their future working environment. Together, students deepened their knowledge regarding food science and chemistry. They were then able to plan and design experiments demonstrating the impact of gluten network formation and ascorbic acid influence onto bread dough and finished product characteristics. This way of teaching was very appreciated by students, nevertheless it highlighted the fact that the professors' investment was considerably high, and that good organization, alignment and preparation prior to the start of this project is key.

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The Effect of Chitosan on the Chemical Structure, Morphology, and Selected Properties of Polyurethane/Chitosan Composites

Polymers ◽

10.3390/polym12051205 ◽

2020 ◽

Vol 12 (5) ◽

pp. 1205

Author(s):

Agnieszka Piotrowska-Kirschling ◽

Joanna Brzeska

Keyword(s):

Chemical Structure ◽

Materials Science ◽

Chemical Properties ◽

Materials Synthesis ◽

Physico Chemical ◽

Structure Morphology ◽

Basic Parameters ◽

Properties Of Materials ◽

The Impact ◽

Positive Effect

Materials science is an interdisciplinary area of studies. This science focuses on the influence of the physico-chemical properties of materials on their application in human everyday lives. The materials’ synthesis should be developed in accordance with sustainable development. Polyurethanes (PUR) represent a significant consumption of plastic in the world. Modification of PUR, e.g., with polysaccharide of natural origin (chitosan, Chit), should have a positive effect on their functional properties and degradability in the natural environment. The basic parameters affecting the scope and direction of changes are the size and quantity of the chitosan particles. The impact assessment of chitosan on the chemical structure, morphology, thermal properties, crystallinity, mechanical properties, flammability, water sorption, adsorption properties, degradability, and biological activity of PUR/Chit composites (without other additives) is discussed in this article. To the best of our knowledge, recent literature does not contain a study discussing the direct impact of the presence of chitosan in the structure of PUR/Chit composite on its properties, regardless of the intended uses. This paper provides an overview of publications, which presents the results of a study on the effect of adding chitosan in polyurethane/chitosan composites without other additives on the properties of polyurethane.

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PCL/POSS Nanocomposites: Effect of POSS Derivative and Preparation Method on Morphology and Properties

Polymers ◽

10.3390/polym11010033 ◽

2018 ◽

Vol 11 (1) ◽

pp. 33 ◽

Cited By ~ 5

Author(s):

Mónica Cobos ◽

Johnny R. Ramos ◽

Dailyn J. Guzmán ◽

M. Dolores Fernández ◽

M. Jesús Fernández

Keyword(s):

Preparation Method ◽

Chemical Properties ◽

Surface Hydrophobicity ◽

Polyhedral Oligomeric Silsesquioxanes ◽

Melt Compounding ◽

Physico Chemical ◽

Amino Derivatives ◽

The One ◽

Crystalline Aggregates

The incorporation of polyhedral oligomeric silsesquioxanes (POSS) molecules as nanoparticles into polymers can provide improved physico-chemical properties. The enhancement depends on the extent of dispersion of the nanofiller, which is determined by the compatibility with the polymer that is by the POSS type, and the processing method. In this study, poly(ε-caprolactone)/POSS derivatives nanocomposites (PCL/POSS) were obtained via solution-casting and melt compounding. Two amino-derivatives containing different alkyl substituents, and ditelechelic POSS-containing hybrid PCL masterbatch were used as nanofillers. The effect of preparation method, POSS content and type on the morphology, thermal, mechanical, and surface properties of nanocomposites were studied. Morphological analysis evidenced the formation of POSS crystalline aggregates, self-assembled POSS molecules of submicrometer size dispersed in the polymer matrix. The best dispersion was achieved using the ditelechelic POSS-containing hybrid PCL masterbatch, and comparing the two amino-POSS derivatives, the one with longer alkyl chain of substituents exhibited better degree of dispersion independent of preparation method. DSC analysis showed the role of POSS derivatives as nucleating agents for PCL. The incorporation of POSS derivatives into the PCL matrix improved thermal stability. The preparation method, POSS type and content had influence on mechanical properties of nanocomposites. POSS nanoparticles enhanced the surface hydrophobicity of PCL.

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