scholarly journals Intelligent copolymers based on poly (N-isopropylacrylamide) PNIPAm with potential use in biomedical applications. Part i: PNIPAm functionalization with 3-butenoic acid and piperazine

2018 ◽  
Vol 1 (1) ◽  
pp. 13 ◽  
Author(s):  
Maria G. Carrero ◽  
James J. Posada ◽  
Marcos A. Sabino
Keyword(s):  
Biomedical Applications ◽  
Chemical Structure ◽  
Morphological Analysis ◽  
Differential Scanning Calorimetric ◽  
Butenoic Acid ◽  
Anchor Points ◽  
Thermosensitive Copolymers ◽  
Interconnected Pore ◽  
Potential Use

The synthesis and characterization of the thermosensitive copolymers based on Poly (N-Isopropylacrylamide) (PNIPAm) and 3-butenoic acid and functionalized with piperazine was carried out. The free radical polymerization of the PNIPA copolymer with 3-butenoic acid was performed under microwave radiation. After obtaining this copolymer, the carboxyl groups present in the copolymer chain were activated with 1-ethyl- (3-3-dimethylaminopropyl) carbodiimide in the presence of N-hydroxysuccinimide, improving its reactivity to incorporate the piperazine through its amino group. The characterization consisted: differential scanning calorimetric and ultraviolet-visible spectrophotometry to determine the LCST phase transition temperature, ranging from (30-35)°C. Structurally it was analyzed by infrared spectroscopy. A morphological analysis was performed using scanning electron microscopy, after simulating an injectable process, with the objective to observe internally the porosity and interconnectivity. The biocompatibility was evaluated through hemocompatibility tests and it was observed that the copolymers obtained were not cytotoxic. In base of the results, the chemical structure of these new copolymers confers a functionality that allows them to serve as nuclei to graft other molecules, such as polysaccharides. Then, the results obtained on the LCST temperature, porosity, interconnected pore network morphology, the ability to be injectable and the biocompatible nature of these copolymers are indicative that these new synthetic biomaterials have the potential to be used in biomedical, pharmacological and for tissue engineering. Also, once their biocompatibility was demonstrate, they may serve to generate interesting compounds having chemical anchor points for the possible addition of polysaccharides using insertion reactions, thereby generating graft copolymers with potential use in biomedical applications.

scholarly journals Incidence and characterisation of Bacillus cereus bacteriophages from Thua Nao, a Thai fermented soybean product

2021 ◽  
Vol 12 (1) ◽  
pp. 85-93
Author(s):  
Wallapat Phongtang ◽  
Ekachai Chukeatirote
Keyword(s):  
Bacillus Cereus ◽  
Food Industry ◽  
Pathogenic Bacteria ◽  
Morphological Analysis ◽  
Food Poisoning ◽  
Fermented Soybean ◽  
Foodborne Pathogenic Bacteria ◽  
Ph Range ◽  
Potential Use

Abstract Bacillus cereus is considered to be an important food poisoning agent causing diarrhea and vomiting. In this study, the occurrence of B. cereus bacteriophages in Thai fermented soybean products (Thua Nao) was studied using five B. cereus sensu lato indicator strains (four B. cereus strains and one B. thuringiensis strain). In a total of 26 Thua Nao samples, there were only two bacteriophages namely BaceFT01 and BaceCM02 exhibiting lytic activity against B. cereus. Morphological analysis revealed that these two bacteriophages belonged to the Myoviridae. Both phages were specific to B. cereus and not able to lyse other tested bacteria including B. licheniformis and B. subtilis. The two phages were able to survive in a pH range between 5 and 12. However, both phages were inactive either by treatment of 50°C for 2 h or exposure of UV for 2 h. It should be noted that both phages were chloroform-insensitive, however. This is the first report describing the presence of bacteriophages in Thua Nao products. The characterization of these two phages is expected to be useful in the food industry for an alternative strategy including the potential use of the phages as a biocontrol candidate against foodborne pathogenic bacteria.

Preparation and Characterization of Gelatin/Oligomeric Proanthocyanidins Composite Microspheres

2011 ◽  
Vol 287-290 ◽  
pp. 132-135
Author(s):  
Ching Wen Lou ◽  
Jin Jia Hu ◽  
Chao Chiung Huang ◽  
Shih Yu Huang ◽  
Hsiu Hui Yeh ◽  
...  
Keyword(s):  
Biomedical Applications ◽  
Air Permeability ◽  
Wound Dressings ◽  
Water Contact ◽  
Composite Microsphere ◽  
Oligomeric Proanthocyanidins ◽  
Composite Microspheres ◽  
Hemostatic Activity ◽  
Potential Use

Gelatin is a heterogeneous mixture of single or multi-stranded polymers made of amino acids. Its film formability, air permeability, biocompatibility, and hemostatic activity render it appropriate for wound dressing. In this study, we used a syringe to drop gelatin solution into oligomeric proanthocyanidins solution to prepare the composite microspheres. Physical properties of the composite microsphere, such as swelling, stability in water, contact angle, and Fourier transform infrared spectroscopy were examined. We aimed at investigating its potential use in promoting wound healing along with wound dressings. The greatest swelling (1480 %) of the gelatin/OPC composite microsphere was achieved in 10 min. The composite microspheres dissolved 90% in the first 60 min during water stability test. Therefore, the developed composite microsphere has great hydrophilic and can be used in biomedical applications.

Synthesis and characterization of graphene-based nanocomposites with potential use for biomedical applications

2013 ◽  
Vol 15 (3) ◽  
Author(s):  
Daniele Nuvoli ◽  
Valeria Alzari ◽  
Roberta Sanna ◽  
Sergio Scognamillo ◽  
Jenny Alongi ◽  
...  
Keyword(s):  
Biomedical Applications ◽  
Synthesis And Characterization ◽  
Potential Use

scholarly journals Chemical characterization of agroforestry solid residues aiming its utilization as adsorbents for metals in water

2015 ◽  
Vol 19 (1) ◽  
pp. 77-83 ◽  
Author(s):  
Francisco H. M. Luzardo ◽  
Fermin G. Velasco ◽  
Clemildes P. Alves ◽  
Ivea K. da S. Correia ◽  
Lázaro L. Cazorla
Keyword(s):  
Adsorption Capacity ◽  
Functional Groups ◽  
Chemical Structure ◽  
Chemical Characterization ◽  
Soluble Solids ◽  
Carbonyl Groups ◽  
Specific Chemical ◽  
Coconut Shells ◽  
Potential Use

In this work, a study of the correlation between the functional groups present in the chemical structure of the fibers of coconut shells, cocoa and eucalyptus, and their adsorption capacity of Cd+2 and Cu+2 ions from water was performed. The content of soluble solids and reactive phenols in aqueous extracts were determined. The chemical functional groups present in the fibers were examined using the IR spectra. The adsorption capacity of the peels was determined using atomic absorption spectrophotometer. For Cd+2, a significant correlation between the adsorption capacity and some specific chemical functional groups present in the fiber was verified. The potential use of these peels, as adsorbent of Cd+2 ions, is based on the presence of OH functional groups such as aryl-OH, aryl-O-CH2 of phenol carboxylic acids, as well as carbonyl groups derived from carboxylic acid salts, in these fibers.

scholarly journals Green Nanobiotechnology: Factors Affecting Synthesis and Characterization Techniques

2014 ◽  
Vol 2014 ◽  
pp. 1-12 ◽  
Author(s):  
Jayanta Kumar Patra ◽  
Kwang-Hyun Baek
Keyword(s):  
Biomedical Applications ◽  
Energy Use ◽  
Synthesis And Characterization ◽  
Factors Affecting ◽  
Synthesis Of Nanoparticles ◽  
Specific Composition ◽  
Pressure Time ◽  
Biological Sources ◽  
Potential Use

Nanobiotechnology is gaining tremendous impetus in this era owing to its ability to modulate metals into their nanosize, which efficiently changes their chemical, physical, and optical properties. Accordingly, considerable attention is being given to the development of novel strategies for the synthesis of different kinds of nanoparticles of specific composition and size using biological sources. However, most of the currently available techniques are expensive, environmentally harmful, and inefficient with respect to materials and energy use. Several factors such as the method used for synthesis, pH, temperature, pressure, time, particle size, pore size, environment, and proximity greatly influence the quality and quantity of the synthesized nanoparticles and their characterization and applications. Additionally, characterization of the synthesized nanoparticles is essential to their potential use in various drug delivery and biomedical applications. The present review highlights various parameters affecting the synthesis of nanoparticles by green nanobiotechnology and different techniques used for characterizing the nanoparticles for their potential use in biomedical and environmental applications.

scholarly journals Synthesis and Characterization of an Amphiphilic Linoleic Acid-g-Quaternary Chitosan with Low Toxicity

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Xiaobin Fang ◽  
Yingqi Xu ◽  
Jinming Zhang ◽  
Xianghong Lu ◽  
Yitao Wang ◽  
...  
Keyword(s):  
Linoleic Acid ◽  
Self Assembly ◽  
Biomedical Applications ◽  
Chemical Structure ◽  
H Nmr ◽  
Low Toxicity ◽  
Low Cytotoxicity ◽  
Average Size ◽  
Novel Drug

A novel amphiphilic derivative of chitosan, namely, a linoleic acid-g-quaternary chitosan (LA-g-QC), was designed and synthesized as low toxic material for biomedical applications in this study. The chemical structure of LA-g-QC was characterized by Fourier transform infrared spectroscopy (FTIR),1H nuclear magnetic resonance (1H-NMR), and elemental analysis. LA-g-QC could form nanosized micelles with self-assembly, which was confirmed by the results of critical micelle concentration (CMC) via fluorescence spectroscopy. The average size of LA-g-QC was 140 nm and its zeta potential was approximately +35.50 mV. CMC value was 31.00 mg/mL. Furthermore, LA-g-QC micelles, at final concentrations between 0.94 μg/mL and 30 μg/mL, did not inhibit the proliferation of HepG2 or SMMC 7721 cell lines. Taken together, LA-g-QC has low cytotoxicity and high potential for the preparation of novel drug-delivery micelles.

scholarly journals Preparation and Characterization of Oxidized Inulin Hydrogel for Controlled Drug Delivery

Pharmaceutics ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 356 ◽  
Author(s):  
Franklin Afinjuomo ◽  
Paris Fouladian ◽  
Ankit Parikh ◽  
Thomas G. Barclay ◽  
Yunmei Song ◽  
...  
Keyword(s):  
Biomedical Applications ◽  
Gravimetric Analysis ◽  
Colon Cancer Cells ◽  
Scanning Calorimetry ◽  
In Vitro Drug Release ◽  
Acidic Conditions ◽  
Direct Targeting ◽  
Potential Use

Inulin-based hydrogels are useful carriers for the delivery of drugs in the colon-targeted system and in other biomedical applications. In this project, inulin hydrogels were fabricated by crosslinking oxidized inulin with adipic acid dihydrazide (AAD) without the use of a catalyst or initiator. The physicochemical properties of the obtained hydrogels were further characterized using different techniques, such as swelling experiments, in vitro drug release, degradation, and biocompatibility tests. The crosslinking was confirmed with Fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA), and differential scanning calorimetry (DSC). In vitro releases of 5-fluorouracil (5FU) from the various inulin hydrogels was enhanced in acidic conditions (pH 5) compared with physiological pH (pH 7.4). In addition, blank gels did not show any appreciable cytotoxicity, whereas 5FU-loaded hydrogels demonstrated efficacy against HCT116 colon cancer cells, which further confirms the potential use of these delivery platforms for direct targeting of 5-FU to the colon.

scholarly journals Intelligent copolymers based on poly (N-isopropilacrylamide). Part ii: Grafts polysaccharide to obtain new biomaterials for biomedical and pharmacological applications

2019 ◽  
Vol 2 (1) ◽  
pp. 17
Author(s):  
Marcos Antonio Sabino ◽  
Maria Gabriela Carrero ◽  
Carlos Julio Rodriguez
Keyword(s):  
Hyaluronic Acid ◽  
Differential Scanning Calorimetric ◽  
High Porosity ◽  
Chemically Modified ◽  
Modification Process ◽  
Graft Polymers ◽  
Ft Ir ◽  
Anchor Points ◽  
Reversible Gel

Biopolymers such as polysaccharides are compounds that have functional groups and they are very susceptible to be used in chemical modifications and also allows them to synthesizer of new copolymers (used as graft-like chains). Poly (N-Isopropylacrylamide) PNIPAm, is a thermosensitive synthetic polymer widely used in the preparation of intelligent gels for the biomedical field, but have some limitations in use as biodegradable matrix or scaffolds. In this research wered the synthesis and characterization of copolymers their PNIPAm grafted with the polysaccharides: chitosan (CS) or hyaluronic acid (HA), were performed to obtain new biodegradable and biocompatible biomaterials that conserve the intelligent character (thermosensitivity).The PNIPAm was in first chemically modified with 3-butenoic acid in order to generate carboxyl end groups on the graft-polymer chain (PNIPAm-co-COOH) which serve as anchor points and then covalently graft the polysaccharides. For the specific case of grafting with hyaluronic acid, it was necessary to perform a second modification using piperazine (PIP) and obtain the graft-polymers PNIPAm-co-COO-g-PIP. All this modification process was previously reported (Carrero et al, 2018). In this case, the polysaccharides used as grafts-like chains were: (1) chitosan oligomers obtained by acid degradation and (2) hyaluronic acid. The characterization of all copolymers obtained was follow by infrared spectroscopic (FT-IR); the differential scanning calorimetric (DSC) technique was used to determine the lower critical solution transition temperature (LCST), resulting in the range of 29-34 °C. Its morphology was studied using scanning electron microscopy (SEM), but previously was simulate an inject process, for the reversible gel character presented by these novel copolymers; resulting a high porosity and interconnection between pores (scaffold-like micrometric structures). Hemocompatibility assays were performed on agar/blood systems, showing non cytotoxicity. All these results give these graftcopolymers a high potentiality of use as scaffolds in tissue engineering and also for pharmacological applications.

Characterization of Wet-Chemically Nanostructured Stainless Steel Surfaces

2001 ◽  
Vol 676 ◽  
Author(s):  
R. Buescher ◽  
H. P. Jennissen ◽  
M. Chatzinikolaidou ◽  
A. Fischer
Keyword(s):  
Stainless Steel ◽  
Acid Treatment ◽  
Biomedical Applications ◽  
Chemical Structure ◽  
Substrate Material ◽  
Passive Layer ◽  
Chemically Modified ◽  
Modification Process ◽  
Steel Surfaces

ABSTRACTA novel surface modification process is presented, which creates a macroscopically smooth and a nanoscopically rough surface on an austenitic stainless steel. The chemical structure of the oxide layer is changed due to the acid treatment, whereas the thickness is not increased. An altered chromiumoxide content in the passive layer connected with a high bonding strength to the substrate material suggests the use of these wet chemically modified steels in biomedical applications.

scholarly journals Thermometric Characterization of Fluorescent Nanodiamonds Suitable for Biomedical Applications

2021 ◽  
Vol 11 (9) ◽  
pp. 4065
Author(s):  
Francisco Pedroza-Montero ◽  
Karla Santacruz-Gómez ◽  
Mónica Acosta-Elías ◽  
Erika Silva-Campa ◽  
Diana Meza-Figueroa ◽  
...  
Keyword(s):  
Biomedical Applications ◽  
Data Representation ◽  
Colour Centres ◽  
High Pressure High Temperature ◽  
Aqueous Environments ◽  
Fluorescent Nanodiamonds ◽  
Low Cytotoxicity ◽  
Scientific Fields ◽  
Potential Use

Nanodiamonds have been studied for several biomedical applications due to their inherent biocompatibility and low cytotoxicity. Recent investigations have shown perspectives in using fluorescent nanodiamonds as nanothermometers because of their optical properties’ dependence on temperature. Easy and accurate localized temperature sensing is essential in a wide variety of scientific fields. Our work demonstrated how the fluorescence spectrum of high-pressure high-temperature fluorescent nanodiamonds of three different sizes: 35 nm, 70 nm and 100 nm, changes with temperature within an important biological temperature range (25 °C to 60 °C). Taking advantage of this phenomenon, we obtained nanothermic scales (NS) from the zero phonon lines (ZPL) of the NV0 and NV− colour centres. In particular, the 100 nm-sized features the more intense fluorescence spectra whose linear dependence with temperature achieved 0.98 R2 data representation values for both NV0 and NV−. This model predicts temperature for all used nanodiamonds with sensitivities ranging from 5.73% °C−1 to 6.994% °C−1 (NV0) and from 4.14% °C−1 to 6.475% °C−1 (NV−). Furthermore, the non-cytotoxic interaction with HeLa cells tested in our study enables the potential use of fluorescence nanodiamonds to measure temperatures in similar nano and microcellular aqueous environments with a simple spectroscopic setup.

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