Dielectric Properties Measurement of Biological Materials Using Non-Destructive Sensors

2015 ◽  
Vol 5 (1) ◽  
pp. 46-56
Author(s):  
N. Aouabdia ◽  
N. E. Belhadj-Tahar ◽  
Georges. Alquié
Keyword(s):  
Dielectric Properties ◽  
Research Work ◽  
Biological Materials ◽  
Liver Fat ◽  
Commercial Software ◽  
Rectangular Patch ◽  
Edge Conditions ◽  
The Moment ◽  
Non Destructive

The authors' research work has for objective the study of a sensor with planar resonator for applications in the non-destructive control. In this context, two approaches were defined. In a first part, a conception, a modeling, a simulation with commercial software (HFSS, CST), a realization and measurements were treated on Rectangular Patch Resonators (RPR). The proposed theoretical analysis is based on the Moment Method (MoM) via the Galerkin's approach, in which three types of entire domain basis functions are used to expand the patch currents. While, the first two types of basic functions involve a set of sinusoidal cavity modes without edge conditions (sbf-wo-ec) and with edge conditions (sbf-w-ec), and in order to incorporate the edge conditions (cp-ec), the third one consists of Chebyshev polynomials combinations with weighting factors. These last ones as well as the Green Dyadic spectral functions are efficiently implanted with compact Fortran 90 codes. Two EM commercial software HFSS and CST was used to validate the proposed RPR prototypes. The exactness of the obtained results is estimated using four prototypes operating near 6 GHz, taking into account only the fundamental mode resonant frequency. The theoretical model is compared with the simulations and the measurement results. The second approach of the authors' work which is developed in this paper is focused on the characterization of biological materials in vitro using the RPR prototypes proposed as applicator in the non-destructive control and the medical domain to find the abnormalities of these tissues such as: eczema, psoriasis, cancer, etc. The authors' center of interest will be managed towards the dielectric properties of the biological material to extract the relative permittivity and the loss factor on several samples (liver, fat, chicken, butter, foie gras, etc.).

Theory, Analysis and Measurements of Rectangular Patch Resonator Sensors

2014 ◽  
Vol 4 (2) ◽  
pp. 8-23
Author(s):  
N. Aouabdia ◽  
N. E. Belhadj-Tahar ◽  
G. Alquie
Keyword(s):  
Theoretical Model ◽  
Dominant Mode ◽  
Theory Analysis ◽  
Modeling Simulation ◽  
Rectangular Patch ◽  
Anisotropic Substrate ◽  
Fortran 90 ◽  
The Moment ◽  
Non Destructive

This paper has for objective to explore the study of a sensor based on a rectangular planar resonator (RPR) for applications to Non-destructive Evaluation (NDE). In this context, conception, modeling, simulation and realization have been made on rectangular structures with an anisotropic substrate and an isotropic superstrate. The theoretical model is based on the moment method (MoM) via Galerkin's approach, in which three types of basis and testing functions are used. These functions as well as the spectral dyadic Green function are efficiently implanted on compact structured Fortran 90 codes. The accuracy of the obtained results is assessed using four prototypes of RPRs operating around 6 GHz, taking only into account the Resonant Frequency (RF) of the fundamental dominant mode. The theoretical model is compared to simulation and measurements results and shown very good agreements. The RPR criteria are established theoretically and validated experimentally with two electromagnetic commercial softwares (HFSS and CST); to be used in future prospects as an electromagnetic (EM) sensor for the characterization of superstrates.

Solubility Enhancement of Poorly Water-Soluble Antifungal Drug Acyclovir by Nanocrystal Formulation Approach

2018 ◽  
Vol 11 (2) ◽  
pp. 4036-4042
Author(s):  
Prakash Goudanavar ◽  
Ankit Acharya ◽  
Vinay C.H
Keyword(s):  
Chemical Interaction ◽  
Research Work ◽  
Antiviral Drug ◽  
In Vitro Release ◽  
Oral Route ◽  
Water Soluble ◽  
Precipitation Method ◽  
Dsc Studies ◽  
Ft Ir

Administration of an antiviral drug, acyclovir via the oral route leads to low and variable bioavailability (15-30%). Therefore, this research work was aimed to enhance bioavailability of acyclovir by nanocrystallization technique. The drug nanocrystals were prepared by anti-solvent precipitation method in which different stabilizers were used. The formed nanocrystals are subjected to biopharmaceutical characterization including solubility, particle size and in-vitro release. SEM studies showed nano-crystals were crystalline nature with sharp peaks. The formulated drug nanocrystals were found to be in the range of 600-900nm and formulations NC7 and NC8 showed marked improvement in dissolution velocity when compared to pure drug, thus providing greater bioavailability. FT-IR and DSC studies revealed the absence of any chemical interaction between drug and polymers used. 

Nyctanthes Arbor-Tristis and its Role in the Alleviation of Arthritic Pain: A Review

2020 ◽  
Vol 16 (8) ◽  
pp. 1147-1156
Author(s):  
Ruchi Singh ◽  
Syed M. Hasan ◽  
Amit Verma ◽  
Sanjay K. Panda
Keyword(s):  
Research Work ◽  
Plant Distribution ◽  
Pharmacological Activities ◽  
Whole Plant ◽  
Modern Drug ◽  
Active Chemical ◽  
Drug Synthesis ◽  
New Compounds

Background: A plant is a reservoir of potentially useful active chemical entities which act as drugs as well as intermediates for the discovery of newer molecules and provide newer leads for modern drug synthesis. The demand for new compounds in the field of medicine and biotechnology is centuries old and with a rise in chronic diseases and resistance to existing drugs in the field of anti-infective agents, the chemicals obtained from plant sources have been an area of attraction. The whole plant has possessed multiple pharmacological activities. This is scientifically established by in-vivo and in-vitro studies. Methods: Various electronic databases such as PubMed, Science Direct, Scopus and Google were searched to collect the data of the present review. All the collected information is categorized into different sections as per the aim of the paper. Results: Fifty-six research and review papers have been studied and were included in this review article. After a detailed study, we provide a significant description of various phytochemicals present in Nyctanthes arbor-tristis Linn., which is responsible for various pharmacological activities. Twenty of studied articles gives a general introduction and ethnobotanical information about the plant, two papers contained microscopic detail of leaf and fruit. Twenty papers contained information about the phytoconstituents present in different parts of Nyctanthes arbor-tristis plant and fourteen articles reported pharmacological activities like antioxidant, anti-inflammatory, antiarthritic, antimicrobial and immunobiotic activity. Conclusion: This review explores the published research work comprising the ethnobotanical description of the subjected plant, distribution, phytochemical profile, and arthritis-related pharmacological activities.

Quality-by-Design Enabled Chitosan Nanoparticles for Antitubercular Therapy: Formulation, Statistical Optimization, and In vitro Characterization

2020 ◽  
Vol 15 ◽  
Author(s):  
Manasi M. Chogale ◽  
Sujay S. Gaikwad ◽  
Savita P. Kulkarni ◽  
Vandana B. Patravale
Keyword(s):  
Side Effects ◽  
Treatment Regimen ◽  
Research Work ◽  
Chitosan Nanoparticles ◽  
In Vitro Release ◽  
Antitubercular Therapy ◽  
Prolonged Treatment ◽  
High Dose ◽  
Average Size

Background: Tuberculosis (TB) continues to be among the leading causes for high mortality among developing countries. Though a seemingly effective treatment regimen against TB is in place, there has been no significant improvement in the therapeutic rates. This is primarily owing to the high drug doses, their associated sideeffects, and prolonged treatment regimen. Discontinuation of therapy due to the severe side effects of the drugs results in the progression of the infection to the more severe drug-resistant TB. Objectives: Reformulation of the current existing anti TB drugs into more efficient dosage forms could be an ideal way out. Nanoformulations have been known to mitigate the side effects of toxic, high-dose drugs. Hence, the current research work involves the formulation of Isoniazid (INH; a first-line anti TB molecule) loaded chitosan nanoparticles for pulmonary administration. Methods: INH loaded chitosan nanoparticles were prepared by ionic gelation method using an anionic crosslinker. Drugexcipient compatibility was evaluated using DSC and FT-IR. The formulation was optimized on the principles of Qualityby-Design using a full factorial design. Results: The obtained nanoparticles were spherical in shape having an average size of 620±10.97 nm and zeta potential +16.87±0.79 mV. Solid state characterization revealed partial encapsulation and amorphization of INH into the nanoparticulate system. In vitro release study confirmed an extended release of INH from the system. In vitro cell line based safety and efficacy studies revealed satisfactory results. Conclusion: The developed nanosystem is thus an efficient approach for antitubercular therapy.

Design and Evaluation of Long Acting Biodegradable PLGA Microspheres for Ocular Drug Delivery

2019 ◽  
Vol 10 ◽  
Author(s):  
Anjali Pandya ◽  
Rajani Athawale ◽  
Durga Puro ◽  
Geeta Bhagwat
Keyword(s):  
Particle Size ◽  
Drug Release ◽  
Degradation Products ◽  
Ex Vivo ◽  
Research Work ◽  
Entrapment Efficiency ◽  
Rational Approach ◽  
Plga Microspheres ◽  
Long Acting

Background: The research work involves development of PLGA biodegradable microspheres loaded with dexamethasome for intraocular delivery. Objective: To design and evaluate long acting PLGA microspheres for ocular delivery of dexamethasone. Method: Present formulation involves the development of long acting dexamethasone loaded microspheres composed of a biodegradable controlled release polymer, Poly(D, L- lactide-co-glycolide) (PLGA), for the treatment of posterior segment eye disorders intravitreally. PLGA with monomer ratio of 50:50 of lactic acid to glycolic acid was used to achieve a drug release up to 45 days. Quality by Design approach was utilized for designing the experiments. Single emulsion solvent evaporation technique along with high pressure homogenization was used to facilitate formation of microspheres. Results: Particle size evaluation, drug content and drug entrapment efficiency were determined for the microspheres. Particle size and morphology was observed using Field Emission Gun-Scanning Electron Microscopy (FEG-SEM) and microspheres were in the size range of 1-5 μm. Assessment of drug release was done using in vitro studies and transretinal permeation was observed by ex vivo studies using goat retinal tissues. Conclusion: Considering the dire need for prolonged therapeutic effect in diseases of the posterior eye, an intravitreal long acting formulation was designed. Use of biodegradable polymer with biocompatible degradation products was a rational approach to achieve this aim. Outcome from present research shows that developed microspheres would provide a long acting drug profile and reduce the frequency of administration thereby improving patient compliance.

Apoprotein C effect on triglyceride transport in tandem-perfused rat hind end and liver

1984 ◽  
Vol 247 (3) ◽  
pp. G305-G310
Author(s):  
W. J. Kortz ◽  
J. R. Nashold ◽  
M. R. Greenfield ◽  
H. Hilderman ◽  
S. H. Quarfordt
Keyword(s):  
Fatty Acid ◽  
Free Fatty Acid ◽  
Fatty Acyl ◽  
Liver Fat ◽  
Molar Ratio ◽  
Perfusion System ◽  
In Vitro Perfusion ◽  
Arterial Inflow ◽  
High Concentrations

The metabolism of double-labeled triglyceride in a synthetic emulsion was defined in an in vitro perfusion system of rat hind end and liver described previously [Am. J. Physiol. 245 (Gastrointest. Liver Physiol. 8): G106-G112, 1983]. The metabolism of [3H]glycerol-[14C]triolein was defined in the absence of added apoproteins and with additions of human CII and both CII and CIII. Without apoprotein, a pronounced lipolysis of the triglyceride was recognized by high concentrations of radiolabeled glycerol and free fatty acid in the perfusate. The removal of an aliquot of hind-end venous effluent 5 min after adding the labeled triglyceride emulsion to the arterial inflow demonstrated a brisk lipolysis of the substrate when incubated outside the perfusion system. The addition of CII protein to the emulsion before its introduction into the tandem system eliminated perfusate lipolysis, both within the perfusion system and in incubations of aliquots withdrawn from the system. Intravascular lipolysis was not seen with triglyceride emulsions containing both CII and CIH or when an aliquot of hind-end venous effluent was incubated with triglycerides that had not been exposed to the perfusion system. The intravascular lipolysis observed for the [14C]triglyceride added to the tandem system without apoproteins was associated with relatively greater recoveries of 14C-fatty acyl in liver, fat, and muscle and relatively greater recoveries of 14CO2 than when CII alone or both CII and CIII were added with the triglyceride. The addition of CIII to CII in a 1:1 molar ratio increased the recovery of 14C-fatty acyl in muscle and the recovery as 14CO2.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Comparison of Fracture Resistance in Thermal and Self-Curing Acrylic Resins—An In Vitro Study

Polymers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1234
Author(s):  
António Sérgio Silva ◽  
Aurora Carvalho ◽  
Pedro Barreiros ◽  
Juliana de Sá ◽  
Carlos Aroso ◽  
...  
Keyword(s):  
Fracture Resistance ◽  
Research Work ◽  
Testing Machine ◽  
In Vitro Study ◽  
Dimensional Accuracy ◽  
Acrylic Resin ◽  
Thermosetting Resins ◽  
Acrylic Resins ◽  
The Difference

Thermal and self-curing acrylic resins are frequently and versatilely used in dental medicine since they are biocompatible, have no flavor or odor, have satisfactory thermal qualities and polishing capacity, and are easy and fast. Thus, given their widespread use, their fracture resistance behavior is especially important. In this research work, we comparatively analyzed the fracture resistance capacity of thermo and self-curing acrylic resins in vitro. Materials and Methods: Five prosthesis bases were created for each of the following acrylic resins: Lucitone®, ProBase®, and Megacryl®, which were submitted to different forces through the use of the CS® Dental Testing Machine, usually mobilized in the context of fatigue tests. To this end, a point was defined in the center of the anterior edge of the aforementioned acrylic resin bases, for which the peak tended until a fracture occurred. Thermosetting resins were, on average, more resistant to fracture than self-curable resins, although the difference was not statistically significant. The thermosetting resins of the Lucitone® and Probase® brands demonstrated behavior that was more resistant to fracture than the self-curing homologues, although the difference was not statistically significant. Thermosetting resins tended to be, on average, more resistant to fracture and exhibited the maximum values for impact strength, compressive strength, tensile strength, hardness, and dimensional accuracy than self-curing resins, regardless of brand.

scholarly journals X-ray Fluorescence Uptake Measurement of Functionalized Gold Nanoparticles in Tumor Cell Microsamples

2021 ◽  
Vol 22 (7) ◽  
pp. 3691
Author(s):  
Oliver Schmutzler ◽  
Sebastian Graf ◽  
Nils Behm ◽  
Wael Y. Mansour ◽  
Florian Blumendorf ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Irradiation Time ◽  
High Sensitivity ◽  
Nanoparticle Uptake ◽  
X Ray ◽  
Functionalized Gold Nanoparticles ◽  
Uptake Measurement ◽  
Prostate Tumor Cells ◽  
Non Destructive

Quantitative cellular in vitro nanoparticle uptake measurements are possible with a large number of different techniques, however, all have their respective restrictions. Here, we demonstrate the application of synchrotron-based X-ray fluorescence imaging (XFI) on prostate tumor cells, which have internalized differently functionalized gold nanoparticles. Total nanoparticle uptake on the order of a few hundred picograms could be conveniently observed with microsamples consisting of only a few hundreds of cells. A comparison with mass spectroscopy quantification is provided, experimental results are both supported and sensitivity limits of this XFI approach extrapolated by Monte-Carlo simulations, yielding a minimum detectable nanoparticle mass of just 5 pg. This study demonstrates the high sensitivity level of XFI, allowing non-destructive uptake measurements with very small microsamples within just seconds of irradiation time.

scholarly journals Moisture Measurement in Paper and Cardboard Packaging Waste Bales for Recycling

2021 ◽  
Vol 11 (10) ◽  
pp. 4586
Author(s):  
Ana Silveira ◽  
João Cardoso ◽  
Maria José Correia ◽  
Graça Martinho
Keyword(s):  
Quality Control ◽  
Dielectric Properties ◽  
Moisture Content ◽  
Reliable Method ◽  
Drying Method ◽  
Waste Streams ◽  
Oven Drying ◽  
Quality Issue ◽  
Commercial Device ◽  
Non Destructive

Moisture content is a quality issue raised by recycling plants in the acceptance of paper and cardboard coming from waste streams. The current way to measure this parameter is by the oven drying method, which is a slow and invasive process, costing time and resources for the recyclers to do this type of quality control. An alternative to such a measurement technique is the use of plate-form devices which indirectly measure the moisture content using the dielectric properties of water and paper. This study has tested this method and developed a representative equation for the use of devices with these properties in the Portuguese market. For that, 48 wastepaper and cardboard bales were tested with both the traditional (oven drying) method and a commercial device equipped with dielectric technology. An equation that fits the studied reality (R2 = 0.76) was achieved, and possible problems regarding the use of this device were tested. The results showed that this type of device could be used as a time- and cost-saving, non-destructive and reliable method in the quality control of wastepaper and cardboard bales.

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