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Fulltext Monitoring model drug microencapsulation in PLGA scaffolds using X-ray powder diffraction

Aina A, Gupta M, Boukari Y, Morris A, Billa N, Doughty S

Saudi Pharm J, 2016 Mar;24(2):227-31.
PMID: 27013917 DOI: 10.1016/j.jsps.2015.03.015

The microencapsulation of three model drugs; metronidazole, paracetamol and sulphapyridine into Poly (dl-Lactide-Co-Glycolide) (PLGA) scaffolds were probed using X-ray Powder Diffraction (XRPD). Changes in the diffraction patterns of the PLGA scaffolds after encapsulation was suggestive of a chemical interaction between the pure drugs and the scaffolds and not a physical intermixture.

Matched MeSH terms: X-Rays
Monte Carlo simulation of gold nanoparticles for X-ray enhancement application

Dheyab MA, Aziz AA, Rahman AA, Ashour NI, Musa AS, Braim FS, et al.

Biochim Biophys Acta Gen Subj, 2023 Apr;1867(4):130318.
PMID: 36740000 DOI: 10.1016/j.bbagen.2023.130318

BACKGROUND: Gold nanoparticles (Au NPs) are regarded as potential agents that enhance the radiosensitivity of tumor cells for theranostic applications. To elucidate the biological mechanisms of radiation dose enhancement effects of Au NPs as well as DNA damage attributable to the inclusion of Au NPs, Monte Carlo (MC) simulations have been deployed in a number of studies.
SCOPE OF REVIEW: This review paper concisely collates and reviews the information reported in the simulation research in terms of MC simulation of radiosensitization and dose enhancement effects caused by the inclusion of Au NPs in tumor cells, simulation mechanisms, benefits and limitations.
MAJOR CONCLUSIONS: In this review, we first explore the recent advances in MC simulation on Au NPs radiosensitization. The MC methods, physical dose enhancement and enhanced chemical and biological effects is discussed, followed by some results regarding the prediction of dose enhancement. We then review Multi-scale MC simulations of Au NP-induced DNA damages for X-ray irradiation. Moreover, we explain and look at Multi-scale MC simulations of Au NP-induced DNA damages for X-ray irradiation.
GENERAL SIGNIFICANCE: Using advanced chemical module-implemented MC simulations, there is a need to assess the radiation-induced chemical radicals that contribute to the dose-enhancing and biological effects of multiple Au NPs.

Matched MeSH terms: X-Rays
Monte Carlo skin dose simulation in intraoperative radiotherapy of breast cancer using spherical applicators

Moradi F, Ung NM, Khandaker MU, Mahdiraji GA, Saad M, Abdul Malik R, et al.

Phys Med Biol, 2017 Jul 28;62(16):6550-6566.
PMID: 28708603 DOI: 10.1088/1361-6560/aa7fe6

The relatively new treatment modality electronic intraoperative radiotherapy (IORT) is gaining popularity, irradiation being obtained within a surgically produced cavity being delivered via a low-energy x-ray source and spherical applicators, primarily for early stage breast cancer. Due to the spatially dramatic dose-rate fall off with radial distance from the source and effects related to changes in the beam quality of the low keV photon spectra, dosimetric account of the Intrabeam system is rather complex. Skin dose monitoring in IORT is important due to the high dose prescription per treatment fraction. In this study, modeling of the x-ray source and related applicators were performed using the Monte Carlo N-Particle transport code. The dosimetric characteristics of the model were validated against measured data obtained using an ionization chamber and EBT3 film as dosimeters. By using a simulated breast phantom, absorbed doses to the skin for different combinations of applicator size (1.5-5 cm) and treatment depth (0.5-3 cm) were calculated. Simulation results showed overdosing of the skin (>30% of prescribed dose) at a treatment depth of 0.5 cm using applicator sizes larger than 1.5 cm. Skin doses were significantly increased with applicator size, insofar as delivering 12 Gy (60% of the prescribed dose) to skin for the largest sized applicator (5 cm diameter) and treatment depth of 0.5 cm. It is concluded that the recommended 0.5-1 cm distance between the skin and applicator surface does not guarantee skin safety and skin dose is generally more significant in cases with the larger applicators.
HIGHLIGHTS: • Intrabeam x-ray source and spherical applicators were simulated and skin dose was calculated. • Skin dose for constant skin to applicator distance strongly depends on applicator size. • Use of larger applicators generally results in higher skin dose. • The recommended 0.5-1 cm skin to applicator distance does not guarantee skin safety.

Matched MeSH terms: X-Rays
Fulltext Morphological Change of Heat Treated Bovine Bone: A Comparative Study

Pramanik S, Hanif ASM, Pingguan-Murphy B, Abu Osman NA

Materials (Basel), 2012 Dec 21;6(1):65-75.
PMID: 28809294 DOI: 10.3390/ma6010065

In this work, untreated bovine cortical bones (BCBs) were exposed to a range of heat treatments in order to determine at which temperature the apatite develops an optimum morphology comprising porous nano hydroxyapatite (nanoHAp) crystals. Rectangular specimens (10 mm × 10 mm × 3-5 mm) of BCB were prepared, being excised in normal to longitudinal and transverse directions. Specimens were sintered at up to 900 °C under ambient pressure in order to produce apatites by two steps sintering. The samples were characterized by thermogravimetric analysis, X-ray diffraction (XRD), and scanning electron microscopy (SEM) attached to an energy-dispersive X-ray spectroscopy detector. For the first time, morphology of the HAp particles was predicted by XRD, and it was verified by SEM. The results show that an equiaxed polycrystalline HAp particle with uniform porosity was produced at 900 °C. It indicates that a porous nanoHAp achieved by sintering at 900 °C can be an ideal candidate as an in situ scaffold for load-bearing tissue applications.

Matched MeSH terms: X-Rays
Fulltext Morphological and optical properties of graphene film synthesized from waste of industrial cooking oil, AYAMAS using DTCVD method

Mohd Muzamir Mahat, Nurfazianawatie Mohd Zin, Nurul Afaah Abdullah, Salifairus Mohammad Jafar, Mohd Firdaus Malek, M. Rusop, et al.

Science Letters, 2020;14(2):24-33.
MyJurnal

The synthesis of graphene by double thermal chemical vapor deposition (DTCVD) using waste of industrial cooking oil (WICO) as a natural carbon source was investigated. The synthesis parameter (Argon gas flow rate) was varied between 50sccm to 300sccm by 50sccm increments. The function of Argon gas is to provide ambient condition, remove the atmospheric air from the tube and could improve the crystallinity of graphene during synthesis. WICO (from AYAMAS food processing) was placed in the first furnace (precursor furnace) and nickel was placed in the second furnace (deposition furnace). During the synthesis, elevated quantities of carbon from the source material are separated and precipitated on the Nickel surface. The sample were characterized by using Field Emission Scanning Electron Microscopy (FESEM), X-Ray Diffraction (XRD), Energy Dispersive X-ray (EDX), and Ultraviolet Visible (UV-Vis) spectroscopy. Based on FESEM images, at 250sccm, hexagonal graphene formation was observed. Besides, optical properties can be seen by UV-Vis and as the results show that 250sccm is the highest reflectivity value. Consequently, graphene synthesis from WICO using various Argon gas flow rate as precursor is successfully demonstrated.

Matched MeSH terms: X-Rays
Fulltext Morphological, Physiochemical and Thermal Properties of Microcrystalline Cellulose (MCC) Extracted from Bamboo Fiber

Rasheed M, Jawaid M, Karim Z, Abdullah LC

Molecules, 2020 Jun 18;25(12).
PMID: 32570929 DOI: 10.3390/molecules25122824

Bamboo fibers are utilized for the production of various structures, building materials, etc. and is of great significance all over the world especially in southeast Asia. In this study, the extraction of microcrystalline cellulose (MCC) was performed using bamboo fibers through acid hydrolysis and subsequently different characterizations were carried out using various advanced techniques. Fourier transform infrared (FTIR) spectroscopy analysis has indicated the removal of lignin from MCC extracted from bamboo pulp. Scanning Electron Microscopy (SEM) revealed rough surface and minor agglomeration of the MCC. Pure MCC, albeit with small quantities of impurities and residues, was obtained, as revealed by Energy Dispersive X-ray (EDX) analysis. X-ray diffraction (XRD) indicates the increase in crystallinity from 62.5% to 82.6%. Furthermore, the isolated MCC has slightly higher crystallinity compared to commercial available MCC (74%). The results of thermal gravimetric analysis (TGA) demonstrate better thermal stability of isolated MCC compared to its starting material (Bamboo fibers). Thus, the isolated MCC might be used as a reinforcing element for the production of green composites and it can also be utilized as a starting material for the production of crystalline nanocellulose in future.

Matched MeSH terms: X-Rays
Fulltext Morphology observation and physical properties of phenolic resin-silicate layered nanocomposites

Norul Azlin, M.Z., Senin, H.B., Kok Sheng, C.

Journal of Nuclear and Related Technologies, 2009;2009(1):121-134.
MyJurnal

Phenolic resin-silica nanocomposites samples in pellet shape have been successfully prepared by intercalation of polymer solution through the hot pressing method. The phenolic resin is modified with organic elastomers of silica nanoparticles, which is about 20 nanometer in diameter. The change of density and porosity was studied based on the addition of silica content in the phenolic resin composites. The densities of composites increased with the addition of the silica content from 10 wt.% to 40 wt.%. On the other hand, the porosity percentage was decreased with increasing of silica contents. The mechanical properties (Young’s modulus, energy to break and time to failure) of the nanocomposites samples were identified using the Universal Testing Material Machine (UTM). The results of Young’s modulus, energy to break and time to failure of the phenolic resin composites were found to be slightly increased with silica content from 10 wt.% to 30 wt.%. The X-Ray Microtomogaphy (XRM) topographies have shown that the porosity exists on fracture structure for each nanocomposite. The nanocomposites surface structure has been analyzed using Scanning Electron Microscope (SEM). The observation shows that the fracture surface of the pure phenolic resin is relatively smooth and glassy, which is typical for a brittle material, but the phenolic resin- silica composites fracture surface is not smooth at all. The observations indicate the pure phenolic resin is brittle than phenolic resin-silica nanocomposites. Consequently, the physical properties of the phenolic resin-silica nanocomposites were improved with the addition of 10 wt.% to 30 wt.% silica contents, as compared to that of the pure phenolic resin.

Matched MeSH terms: X-Rays
N-O, carboxymethyl chitosan enhanced scaffold porosity and biocompatibility under e-beam irradiation at 50 kGy

Lee SY, Kamarul T

Int J Biol Macromol, 2014 Mar;64:115-22.
PMID: 24325858 DOI: 10.1016/j.ijbiomac.2013.11.039

In this study, a chitosan co-polymer scaffold was prepared by mixing poly(vinyl alcohol) (PVA), NO, carboxymethyl chitosan (NOCC) and polyethylene glycol (PEG) solutions to obtain desirable properties for chondrocyte cultivation. Electron beam (e-beam) radiation was used to physically cross-link these polymers at different doses (30 kGy and 50 kGy). The co-polymers were then lyophilized to form macroporous three-dimensional (3-D) matrix. Scaffold morphology, porosity, swelling properties, biocompatibility, expression of glycosaminoglycan (GAG) and type II collagen following the seeding of primary chondrocytes were studied up to 28 days. The results demonstrate that irradiation of e-beam at 50 kGy increased scaffold porosity and pore sizes subsequently enhanced cell attachment and proliferation. Scanning electron microscopy and transmission electron microscopy revealed extensive interconnected microstructure of PVA-PEG-NOCC, demonstrated cellular activities on the scaffolds and their ability to maintain chondrocyte phenotype. In addition, the produced PVA-PEG-NOCC scaffolds showed superior swelling properties, and increased GAG and type II collagen secreted by the seeded chondrocytes. In conclusion, the results suggest that by adding NOCC and irradiation cross-linking at 50 kGy, the physical and biological properties of PVA-PEG blend can be further enhanced thereby making PVA-PEG-NOCC a potential scaffold for chondrocytes.

Matched MeSH terms: X-Rays
Fulltext Nano-structural study of microfibrils in Acacia Mangium wood using small- angle x-ray scattering (SAXS)

Tabet, Tamer A., Fauziah Abdul Aziz, Shahidan Radiman

Journal of Nuclear and Related Technologies, 2007;2007(1):209-216.
MyJurnal

Small-angle X-ray scattering (SAXS) was used to investigate the nanostructure of the microfibrils of cell wall in Acacia Mangium wood. Parameters, such as the fibre length (L), surface area of the single fibre (S), the correspondence distance from the center of the fibre to the center of its neighbor and the shape of the fibre were determined as a function to the distance from pith towards the bark. The results indicate that the fibre length ranged from 53.44 nm to 13.72 nm from pith to bark. Surface area of the single fibre varied from 0.65 nm 2 to 4.36 nm 2 , the highest being found at the end of bark region. The mean value of the correspondence distance is 13.95 nm. Surface structure analysis from scattering graph showed a rod shape of fibre in the pith region of Acacia Mangium wood. The use of SAXS technique and scanning electron microscope (SEM) micrographs gives the most reliable dimensions values.

Matched MeSH terms: X-Rays
Nanomedicines guided nanoimaging probes and nanotherapeutics for early detection of lung cancer and abolishing pulmonary metastasis: Critical appraisal of newer developments and challenges to clinical transition

Gao X, Guo L, Li J, Thu HE, Hussain Z

J Control Release, 2018 12 28;292:29-57.
PMID: 30359665 DOI: 10.1016/j.jconrel.2018.10.024

Lung cancer (LC) is the second most prevalent type of cancer and primary cause of mortality among both men and women, worldwide. The most commonly employed diagnostic modalities for LC include chest X-ray (CXR), magnetic-resonance-imaging (MRI), computed tomography (CT-scan), and fused-positron-emitting-tomography-CT (PET-CT). Owing to several limitations associated with the use of conventional diagnostic tools such as radiation burden to the patient, misleading diagnosis ("missed lung cancer"), false staging and low sensitivity and resolution, contemporary diagnostic regimen needed to be employed for screening of LC. In recent decades, nanotechnology-guided interventions have been transpired as emerging nanoimaging probes for detection of LC at advanced stages, while producing signal amplification, better resolution for surface and deep tissue imaging, and enhanced translocation and biodistribution of imaging probes within the cancerous tissues. Besides enormous potential of nanoimaging probes, nanotechnology-based advancements have also been evidenced for superior efficacy for treatment of LC and abolishing pulmonary metastasis (PM). The success of nanotherapeutics is due to their ability to maximise translocation and biodistribution of anti-neoplastic agents into the tumor tissues, improve pharmacokinetic profiles of anti-metastatic agents, optimise target-specific drug delivery, and control release kinetics of encapsulated moieties in target tissues. This review aims to overview and critically discuss the superiority of nanoimaging probes and nanotherapeutics over conventional regimen for early detection of LC and abolishing PM. Current challenges to clinical transition of nanoimaging probes and therapeutic viability of nanotherapeutics for treatment for LC and PM have also been pondered.

Matched MeSH terms: X-Rays
Fulltext Neuroendocrine tumour of the lung: a diagnostic challenge

Nur Hidayah Bahrom, Anis Safura Ramli, Nor Suraya Samsudin, Norliana Dalila Mohamad Ali, Nor Salmah Bakar

Journal of Clinical and Health Sciences, 2019;4(2):97-104.
MyJurnal

This is a case of a 62-year-old Indian man who was diagnosed with a rare type of lung
neuroendocrine tumour (NET) of atypical carcinoid (AC) subtype which comprises only 0.1%–
0.2% of pulmonary neoplasms. He initially presented to a private hospital in May 2018 with a
6-month history of chronic productive cough and haemoptysis. Chest X-Ray (CXR), CT scan,
bronchoscopy, biopsy and broncho-alveolar lavage were conducted. At this stage, imaging and
histopathological investigations were negative for malignancy. Diagnosis of bronchiectasis was
made and he was treated with antibiotic and tranexamic acid. Due to financial difficulties, his
care was transferred to a university respiratory clinic in June 2018. His condition was monitored
with CXR at every visit and treatment with tranexamic acid was continued for 6 months.
However, due to persistent haemoptysis, he presented to the university primary care clinic in
Dec 2018. Investigations were repeated in January 2019 where his CXR showed increased
opacity of the left retrocardiac region and CT scan revealed a left lower lobe endobronchial
mass causing collapse with mediastinal lymphadenopathy suggestive of malignancy.
Bronchoscopy, biopsy and histopathology confirmed the presence of NET. Although the Ki-67
index was low, the mitotic count, presence of necrosis and evidence of liver metastases
favoured the diagnosis of AC. A positron emission tomography Ga-68 DONATOC scan showed
evidence of somatostatin receptor avid known primary malignancy in the lungs with suspicions
of liver metastasis. He was subsequently referred to the oncology team and chemotherapy was
initiated. This case highlights the challenge in diagnosis and management of patients with AC.
Physicians ought to be vigilant and have a high index of suspicion in patients who present with
persistent symptoms on multiple visits. Early diagnosis of NET would prevent metastasis and
provide better prognosis. Continuous follow-up shared care between primary care and
secondary care physicians is also essential to provide ongoing psychosocial support for
patients with NET, especially those with metastatic disease

Matched MeSH terms: X-Rays
Fulltext Neutron-activated biodegradable samarium-153 acetylacetonate-poly-L-lactic acid microspheres for intraarterial radioembolization of hepatic tumors

Wong YH, Tan HY, Kasbollah A, Abdullah BJJ, Acharya RU, Yeong CH

World J Exp Med, 2020 Mar 30;10(2):10-25.
PMID: 32266125 DOI: 10.5493/wjem.v10.i2.10

BACKGROUND: Liver cancer is the 6th most common cancer in the world and the 4th most common death from cancer worldwide. Hepatic radioembolization is a minimally invasive treatment involving intraarterial administration of radioembolic microspheres.
AIM: To develop a neutron-activated, biodegradable and theranostics samarium-153 acetylacetonate (153SmAcAc)-poly-L-lactic acid (PLLA) microsphere for intraarterial radioembolization of hepatic tumors.
METHODS: Microspheres with different concentrations of 152SmAcAc (i.e., 100%, 150%, 175% and 200% w/w) were prepared by solvent evaporation method. The microspheres were then activated using a nuclear reactor in a neutron flux of 2 × 1012 n/cm2/s1, converting 152Sm to Samarium-153 (153Sm) via152Sm (n, γ) 153Sm reaction. The SmAcAc-PLLA microspheres before and after neutron activation were characterized using scanning electron microscope, energy dispersive X-ray spectroscopy, particle size analysis, Fourier transform infrared spectroscopy, thermo-gravimetric analysis and gamma spectroscopy. The in-vitro radiolabeling efficiency was also tested in both 0.9% sodium chloride solution and human blood plasma over a duration of 550 h.
RESULTS: The SmAcAc-PLLA microspheres with different SmAcAc contents remained spherical before and after neutron activation. The mean diameter of the microspheres was about 35 µm. Specific activity achieved for 153SmAcAc-PLLA microspheres with 100%, 150%, 175% and 200% (w/w) SmAcAc after 3 h neutron activation were 1.7 ± 0.05, 2.5 ± 0.05, 2.7 ± 0.07, and 2.8 ± 0.09 GBq/g, respectively. The activity of per microspheres were determined as 48.36 ± 1.33, 74.10 ± 1.65, 97.87 ± 2.48, and 109.83 ± 3.71 Bq for 153SmAcAc-PLLA microspheres with 100%, 150%, 175% and 200% (w/w) SmAcAc. The energy dispersive X-ray and gamma spectrometry showed that no elemental and radioactive impurities present in the microspheres after neutron activation. Retention efficiency of 153Sm in the SmAcAc-PLLA microspheres was excellent (approximately 99%) in both 0.9% sodium chloride solution and human blood plasma over a duration of 550 h.
CONCLUSION: The 153SmAcAc-PLLA microsphere is potentially useful for hepatic radioembolization due to their biodegradability, favorable physicochemical characteristics and excellent radiolabeling efficiency. The synthesis of the formulation does not involve ionizing radiation and hence reducing the complication and cost of production.

Matched MeSH terms: X-Rays
Fulltext Novel Functionalized Polythiophene-Coated Fe₃O₄ Nanoparticles for Magnetic Solid-Phase Extraction of Phthalates

Baharin SNA, Muhamad Sarih N, Mohamad S

Polymers (Basel), 2016 Apr 28;8(5).
PMID: 30979266 DOI: 10.3390/polym8050117

Poly(phenyl-(4-(6-thiophen-3-yl-hexyloxy)-benzylidene)-amine) (P3TArH) was successfully synthesized and coated on the surface of Fe₃O₄ magnetic nanoparticles (MNPs). The nanocomposites were characterized by Fourier transform infra-red (FTIR), X-ray diffractometry (XRD), Brunauer-Emmett-Teller (BET) surface area analysis, analyzer transmission electron microscopy (TEM) and vibrating sample magnetometry (VSM). P3TArH-coated MNPs (MNP@P3TArH) showed higher capabilities for the extraction of commonly-used phthalates and were optimized for the magnetic-solid phase extraction (MSPE) of environmental samples. Separation and determination of the extracted phthalates, namely dimethyl phthalate (DMP), diethyl phthalate (DEP), dipropyl phthalate (DPP), dibutyl phthalate (DBP), butyl benzyl phthalate (BBP), dicyclohexyl phthalate (DCP), di-ethylhexyl phthalate (DEHP) and di-n-octyl phthalate (DNOP), were conducted by a gas chromatography-flame ionization detector (GC-FID). The best working conditions were as follows; sample at pH 7, 30 min extraction time, ethyl acetate as the elution solvent, 500-µL elution solvent volumes, 10 min desorption time, 10-mg adsorbent dosage, 20-mL sample loading volume and 15 g·L-1 concentration of NaCl. Under the optimized conditions, the analytical performances were determined with a linear range of 0.1⁻50 µg·L-1 and a limit of detection at 0.08⁻0.468 µg·L-1 for all of the analytes studied. The intra-day (n = 7) and inter-day (n = 3) relative standard deviations (RSD%) of three replicates were each demonstrated in the range of 3.7⁻4.9 and 3.0⁻5.0, respectively. The steadiness and reusability studies suggested that the MNP@P3TArH could be used up to five cycles. The proposed method was executed for the analysis of real water samples, namely commercial bottled mineral water and bottled fresh milk, whereby recoveries in the range of 68%⁻101% and RSD% lower than 7.7 were attained.

Matched MeSH terms: X-Rays
Novel Synthesis and Characterization Studies of Spinel Ni x Co1-xAl₂O₄ (x= 0.0 to 1.0) Nano-Catalysts for the Catalytic Oxidation of Benzyl Alcohol

Suguna S, Shankar S, Jaganathan SK, Manikandan A

J Nanosci Nanotechnol, 2018 Feb 01;18(2):1019-1026.
PMID: 29448527 DOI: 10.1166/jnn.2018.13960

Ni-doped cobalt aluminate NixCo1-xAl2O4 (x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0) spinel nanoparticles were successfully synthesized by a simple microwave combustion method using urea as the fuel and as well as reducing agent. X-ray powder diffraction (XRD) was confirmed the formation of single phase, cubic spinel cobalt-nickel aluminate structure without any other impurities. Average crystallite sizes of the samples were found to be in the range of 18.93 nm to 21.47 nm by Scherrer's formula. Fourier transform infrared (FT-IR) spectral analysis was confirmed the corresponding functional groups of the M-O, Al-O and M-Al-O (M = Co and Ni) bonds of spinel NixCo1-xAl2O4 structure. Scanning electron microscope (SEM) and transmission electron microscope (TEM) images was confirmed the particle like nanostructured morphology. Energy band gap (Eg) value was calculated using UV-Visible diffuse reflectance spectra (DRS) and the Eg values increased with increasing Ni2+ dopant from x = 0.2 (3.58 eV) to x = 1.0 (4.15 eV). Vibrating sample magnetometer (VSM) measurements exposed that undoped and Ni-doped CoAl2O4 samples have superparamagnetic behavior and the magnetization (Ms) values were increased with increasing Ni2+ ions. Spinel NixCo1-xAl2O4 samples has been used for the catalytic oxidation of benzyl alcohol into benzaldehyde and was found that the sample Ni0.6Co0.4Al2O4 showed higher conversion 94.37% with 100% selectivity than other samples, which may be due to the smaller particle size and higher surface area.

Matched MeSH terms: X-Rays
Fulltext Novel chemical synthesis and characterization of copper pyrovanadate nanoparticles and its influence on the flame retardancy of polymeric nanocomposites

Ghiyasiyan-Arani M, Masjedi-Arani M, Ghanbari D, Bagheri S, Salavati-Niasari M

Sci Rep, 2016 05 04;6:25231.
PMID: 27143312 DOI: 10.1038/srep25231

In this work, copper pyrovanadate (Cu3V2O7(OH)2(H2O)2) nanoparticles have been synthesized by a simple and rapid chemical precipitation method. Different copper-organic complexes were used to control the size and morphology of products. The morphology and structure of the as-synthesized products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectrum, electron dispersive X-ray spectroscopy (EDX), thermal gravimetric analysis (TGA), differential thermal analysis (DTA) and photoluminescence (PL) spectroscopy. The influence of copper pyrovanadate nanostructures on the flame retardancy of the polystyrene, poly vinyl alcohol and cellulose acetate was studied. Dispersed nanoparticles play the role of a magnetic barrier layer, which slows down product volatilization and prevents the flame and oxygen from the sample during decomposition of the polymer. Cu3V2O7(OH)2(H2O)2 is converted to Cu3V2O8 with an endothermic reaction which simultaneously releases water and decrease the temperature of the flame region.

Matched MeSH terms: X-Rays
One pot synthesis, molecular structure and spectroscopic studies (X-ray, IR, NMR, UV-Vis) of novel 2-(4,6-dimethoxy-1,3,5-triazin-2-yl) amino acid ester derivatives

El-Faham A, Soliman SM, Osman SM, Ghabbour HA, Siddiqui MR, Fun HK, et al.

Spectrochim Acta A Mol Biomol Spectrosc, 2016 Apr 15;159:184-98.
PMID: 26845586 DOI: 10.1016/j.saa.2016.01.051

Novel series of 2-(4,6-dimethoxy,1,3,5-triazin-2-yl) amino acid ester derivatives were synthesized using simple one pot method in methanol. The products were obtained in high yields and purities as observed from their spectral data, elemental analyses, GC-MS and X-ray crystallographic analysis. The B3LYP/6-311G(d,p) calculated molecular structures are well correlated with the geometrical parameters obtained from the X-ray analyses. The spectroscopic properties such as IR vibrational modes, NMR chemical shifts and UV-Vis electronic transitions were discussed both experimentally and theoretically. The IR vibrational frequencies showed good correlations with the experimental data (R(2)=0.9961-0.9995). The electronic spectra were assigned based on the TD-DFT results. Intense electronic transition band is calculated at 198.1nm (f=0.1389), 204.2nm (f=0.2053), 205.0 (f=0.1704) and 205.7 (0.2971) for compounds 6a-i, respectively. The molecular orbital energy levels contributed in the longest wavelength transition band were explained. For all compounds, the experimental wavelengths showed red shifts compared to the calculations due to the solvent effect. The NMR chemical shifts were calculated using GIAO method. The NBO analyses were performed to predict the stabilization energies due to the electron delocalization processes occur in the studied systems.

Matched MeSH terms: X-Rays
Fulltext Optical absorption and photoluminescence studies of gold nanoparticles deposited on porous silicon

Amran TS, Hashim MR, Al-Obaidi NK, Yazid H, Adnan R

Nanoscale Res Lett, 2013 Jan 18;8(1):35.
PMID: 23331761 DOI: 10.1186/1556-276X-8-35

We present an investigation on a coupled system consists of gold nanoparticles and silicon nanocrystals. Gold nanoparticles (AuNPs) embedded into porous silicon (PSi) were prepared using the electrochemical deposition method. Scanning electron microscope images and energy-dispersive X-ray results indicated that the growth of AuNPs on PSi varies with current density. X-ray diffraction analysis showed the presence of cubic gold phases with crystallite sizes around 40 to 58 nm. Size dependence on the plasmon absorption was studied from nanoparticles with various sizes. Comparison with the reference sample, PSi without AuNP deposition, showed a significant blueshift with decreasing AuNP size which was explained in terms of optical coupling between PSi and AuNPs within the pores featuring localized plasmon resonances.

Matched MeSH terms: X-Rays
Fulltext Optimization of Aceclofenac Proniosomes by Using Different Carriers, Part 1: Development and Characterization

Sammour RMF, Taher M, Chatterjee B, Shahiwala A, Mahmood S

Pharmaceutics, 2019 Jul 18;11(7).
PMID: 31323799 DOI: 10.3390/pharmaceutics11070350

In the contemporary medical model world, the proniosomal system has been serving as a new drug delivery system that is considered to significantly enhance the bioavailability of drugs with low water solubility. The application of this system can improve the bioavailability of aceclofenac that is used for the relief of pain and inflammation in osteoarthritis, rheumatoid arthritis, and ankylosing spondylitis. The present study is intended to develop an optimized proniosomal aceclofenac formula by the use of different carriers. Aceclofenac proniosomes have been prepared by slurry method, and different carriers such as maltodextrin, mannitol, and glucose were tried. Prepared proniosomes characterized by differential scanning calorimetry (DSC) analysis and Fourier transform infrared (FTIR) analysis revealed the compatibility of the drug chosen with the ingredient added, powder X-ray diffractometry (XRD) confirmed the amorphous phase of the prepared proniosomes, and finally, the surfactant layer was observed by scanning electron microscopy (SEM). Aceclofenac physical state transformations were confirmed with all formulas but maltodextrin proniosomes exhibited solubility more than other formulations. HPLC method has been used to analyze the niosomes derived from proniosomes in terms of their entrapment capability and drug content. The obtained results revealed that aceclofenac proniosomes can be successfully prepared by using different carriers.

Matched MeSH terms: X-Rays
Fulltext Overuse, overdose, overdiagnosis… overreaction?

Ho E

Biomed Imaging Interv J, 2010 Jul-Sep;6(3):e8.
PMID: 21611049 DOI: 10.2349/biij.6.3.e8

When x-rays were first discovered, the harmful effects of radiation had to be manifest in the early users before they were known. Today, radiation protection and safety have been established and the effects of radiation, as well as its risks, are known. Even so, medical radiation, in particular the growth in the use of computed tomography (CT), has resulted in soaring radiation doses received by the population in general. Inappropriate use has resulted in overuse, overdose and, perhaps, overdiagnosis, especially when used in screening. In the quest to control and curb the use of procedures involving radiation, however, we must be careful not to provoke a pandemic of irrational fear of radiation. Overreaction to the overuse and overdose of radiation might deter patients from life-saving procedures.

Matched MeSH terms: X-Rays
Fulltext PREPARATION AND CHARACTERIZATION OF MAGNESIUM/ALUMINIUM LAYERED DOUBLE HYDROXIDE AS FILLER IN LOW-DENSITY POLYETHYLENE COMPOSITE

NUR ATHIRAH ZULKIFLI, MOHD AIDIL ADHHA ABDULLAH, MAZIDAH MAMAT

UMT Journal of Undergraduate Research, 2021;3(1):1-6.
MyJurnal

Polymer had been widely used in industries nowadays. However, the properties of the polymer itself are limited to a particular application. This study describes synthetic clay, layered double hydroxide (LDH), as a filler in low-density polyethylene (LDPE) composite. LDHs of magnesium/aluminium-dodecyl sulfate (Mg/Al-DS) and its grafted with triethoxymethylsilane (TEMS), (TEMS-g-Mg/Al-DS) were synthesized through co-precipitation and salinization reaction methods. The presence of alkyl group, v(C-H) in both LDH had confirmed through Fourier transform infrared (FTIR). The appearance of peaks in FTIR spectra within the absorbance range of 2800 – 2930 cm-1indicates a successful surface modification of LDH, supported by the changes of interlayer spacing and the presence of carbon from X-ray diffractogram and CHNS elemental analysis, respectively. The synthesized LDH was mixed with LDPE via melt intercalation method. The LDH modification resulted in higher interaction and compatibility between the LDPE matrix and LDH by the formation exfoliated type of nanocomposites, as suggested by XRD analysis.

Matched MeSH terms: X-Rays

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