scholarly journals Metal ions leachables from fake orthodontic braces incubated in simulated body fluid

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Riyam Haleem ◽  
Noor Ayuni Ahmad Shafiai ◽  
Siti Noor Fazliah Mohd Noor

Abstract Background The demand for fake braces usage in Southeast Asia are increasing but lack of certification and information on fake braces as medical devices from regulated bodies raised a concern towards its safety. The aim of this study was to determine the types of metal ion leachable from removable fake braces based on heavy metal ions present in metallic materials, immersed in simulated body fluid (SBF) and analysed using inductively coupled plasma atomic emission spectroscopy. Methods Three sets of fake braces and one control were dissembled to only their brackets and archwires and immersed separately in SBF. They were placed in an incubator shaker at a temperature of 37 °C at 50 rpm. A 3.0 ml measurement of SBF was taken out from the sample containers at days 7, 14 and 28 and kept at − 20 °C for further analysis. Data were analysed using SPSS version 26.0 (IBM, Armonk, USA) (P < 0.05). Descriptive and one-way ANOVA analyses with Bonferroni post hoc tests were used to assess the significant differences between the metal ions released in SBF from the control samples and fake braces. Results All 23 elements under investigation except Si ions were detected from the control samples and fake braces. There were significant increased K ions and reduced levels of Mg ions from the fake archwires and brackets. Most ions released were less than 10 mg/L (Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, Cd, Pb, Al) or 1 mg/L (Li, Ba) into the SBF medium. Conclusion There were significant release of Ca and K ions from the fake samples. Elements such as Li, Ba, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, Cd and Sb had increased in concentration at day 7 and the concentration plateaued until day 28.

Pharmacology ◽  
2019 ◽  
Vol 104 (1-2) ◽  
pp. 98-112 ◽  
Author(s):  
Katsuaki Dan ◽  
Naohiro Katoh ◽  
Takaaki Matsuoka ◽  
Katsuyuki Fujinami

Background: Historical evidence has verified the multifaceted antiviral efficacy of polyoxometalates (PMs). Methods: We carried out a study to investigate the antimicrobial effects of each of the 5 substances comprising virus block (VB): 3 PMs that have antibacterial and antiviral activity, an antibiotic agent, and an antibacterial agent. We also investigated the effectiveness of the addition of VB to moist hand towels in a study involving 120 volunteers. The time-dependent changes in metal ion concentrations in aqueous VB solution were analyzed using inductively coupled plasma atomic emission spectroscopy. Results: The metal elements in the aqueous VB solution remained stable for 12 weeks without undergoing time-dependent changes. Discussion: Further investigations were performed to study hand hygiene using moist hand towels in daily life settings. To this end, 120 volunteers provided 240 specimens that were used to investigate the presence of antibacterial compounds on the volunteers’ hands before and after hand towel use. An aliquot of each specimen was suspended in phosphate-buffered saline and plated on agar media, and the number of colonies formed was counted. Normal bacterial flora found on the hands of the volunteers was investigated before and after the use of 4 different moist hand towels. Conclusions: The effects of VB and PMs were superior to those of commercial moist hand towels, indicating that effective data were obtained that may be useful for the practical application of the tested items.


2019 ◽  
Vol 9 (3) ◽  
pp. 504 ◽  
Author(s):  
Yan Wang ◽  
Yanci Hu ◽  
Pengfei Qi ◽  
Lei Guo

Huge amounts of waste acid and wastewater are generated during the corncob pretreatment process, which limits chemical utilization of biomass resources to produce value-added chemicals and biofuels. In this work, a new approach, i.e., reuse of the corncob pretreatment liquid, is proposed toward diminishing acid and water consumption. Metal ions and soluble proteins in the pretreatment liquid were analyzed by the inductively coupled plasma atomic emission spectroscopy (ICP-AES) and the Coomassie rilliant blue G250 method, respectively. The results showed that the increament of soluble proteins and total metal ions in solution by three reuse rounds of the pretreatment liquid is nearly identical to that in solution by new added pretreatment liquid. Besides, the surface morphology of the corncob obtained by three reuse rounds of the liquid pretreatment did not exhibit significant difference comparing to that of the corncob acquired by new liquid pretreatment. Further, selection basis of an optimal reuse round of the pretreatment liquid is suggested depending on the effective removal of soluble proteins and metal ions from corncobs. By repeated use of the pretreatment liquid, the consumption of both acid and water during the corncob pretreatment process is expected to be significantly reduced.


2008 ◽  
Vol 587-588 ◽  
pp. 138-142 ◽  
Author(s):  
A.M.B. Silva ◽  
Rui N. Correia ◽  
J.M. Oliveira ◽  
Maria Helena F.V. Fernandes

This study compares the in vitro behaviour in SBF of glasses from two different systems, TiO2-CaO-P2O5 and SiO2-CaO-P2O5 with the same TiO2 and SiO2 molar content, in order to evaluate the effect of TiO2 and SiO2 on the surface reactivity of those glasses. The glass formation regions in both systems were observed for compositions with less than 40 mol% TiO2 and 40 mol% SiO2, respectively. Four glasses with similar TiO2 and SiO2 molar contents have been selected for comparison. These glasses are equimolar in CaO and P2O5 with TiO2 or SiO2 varying from 4 to 33 mol %. Powder glasses were immersed in Simulated Body Fluid (SBF) and kept at 37°C for different times, up to 14 days. Surfaces were observed by Scanning Electron Microscopy (SEM) and specimen ion leaching to SBF was studied by Inductively Coupled Plasma (ICP) spectroscopy. Preliminary spectroscopic studies by Raman were performed to identify the structure of the glasses. For glasses of the SiO2-CaO-P2O5 system a significant dissolution of all ions was observed together with the formation of phosphoric acid. In opposition, the immersion of TiO2-CaO-P2O5 glasses produced a small Ca consumption and stable Ti and P concentrations, indicating the formation of a Ca-P rich layer on these glasses. The observed differences in the dissolution behaviour are tentatively explained in terms of the glass structures obtained by spectroscopy.


2021 ◽  
Vol 20 (2) ◽  
Author(s):  
Siti Hajjar Nasir ◽  
Muhammad Syahmi Mohamad Amran ◽  
Muhammad Muaz Abidin Mustaffar

INTRODUCTION: The growing demand for orthodontic braces among Malaysians has led to the development of fake braces. These fake braces services are illegal and their brackets are reported to be of inferior quality. Fake braces are constantly being exposed to the saliva intraorally, hence they are susceptible to corrosion. This study was conducted to investigate the release of metal ions as a result of corrosion from standard and fake orthodontic braces immersed in artificial saliva of different pH. MATERIALS AND METHODS: A total of six different types of brackets (three from standard and three from fake braces) were immersed in containers containing 5 mL of artificial saliva of pH 4.9 and pH 7.8. The samples were collected for analysis on day 1, day 14, and day 28 using Inductively-Coupled Plasma Mass Spectrometry (ICPMS) to evaluate the amount of metal ion released. Statistical analysis was performed to isolate the significant difference of metal ions released between two types of braces in different pH solutions. RESULTS: The release of aluminum, nickel, chromium, manganese and copper were observed and analyzed. Fake braces released the highest concentration of chromium, manganese, and nickel ions in both artificial saliva as compared to standard braces. Brackets immersed in pH 4.9 released a higher number of ions compared to pH 7.8. CONCLUSION: This study showed that fake braces released the highest concentration of metal ions as compared to standard braces. Both time and pH influenced the release of metal ions from orthodontic brackets.


2018 ◽  
Author(s):  
Danila Barskiy ◽  
Lucia Ke ◽  
Xingyang Li ◽  
Vincent Stevenson ◽  
Nevin Widarman ◽  
...  

<p>Hyperpolarization techniques based on the use of parahydrogen provide orders of magnitude signal enhancement for magnetic resonance spectroscopy and imaging. The main drawback limiting widespread applicability of parahydrogen-based techniques in biomedicine is the presence of organometallic compounds (the polarization transfer catalysts) in solution with hyperpolarized contrast agents. These catalysts are typically complexes of platinum-group metals and their administration in vivo should be avoided.</p> <p><br></p><p>Herein, we show how extraction of a hyperpolarized compound from an organic phase to an aqueous phase combined with a rapid (less than 10 seconds) Ir-based catalyst capture by metal scavenging agents can produce pure parahydrogen-based hyperpolarized contrast agents as demonstrated by high-resolution nuclear magnetic resonance (NMR) spectroscopy and inductively coupled plasma atomic emission spectroscopy (ICP-AES). The presented methodology enables fast and efficient means of producing pure hyperpolarized aqueous solutions for biomedical and other uses.</p>


2018 ◽  
Author(s):  
Danila Barskiy ◽  
Lucia Ke ◽  
Xingyang Li ◽  
Vincent Stevenson ◽  
Nevin Widarman ◽  
...  

<p>Hyperpolarization techniques based on the use of parahydrogen provide orders of magnitude signal enhancement for magnetic resonance spectroscopy and imaging. The main drawback limiting widespread applicability of parahydrogen-based techniques in biomedicine is the presence of organometallic compounds (the polarization transfer catalysts) in solution with hyperpolarized contrast agents. These catalysts are typically complexes of platinum-group metals and their administration in vivo should be avoided.</p> <p><br></p><p>Herein, we show how extraction of a hyperpolarized compound from an organic phase to an aqueous phase combined with a rapid (less than 10 seconds) Ir-based catalyst capture by metal scavenging agents can produce pure parahydrogen-based hyperpolarized contrast agents as demonstrated by high-resolution nuclear magnetic resonance (NMR) spectroscopy and inductively coupled plasma atomic emission spectroscopy (ICP-AES). The presented methodology enables fast and efficient means of producing pure hyperpolarized aqueous solutions for biomedical and other uses.</p>


2020 ◽  
Vol 86 (5) ◽  
pp. 16-21
Author(s):  
T. A. Karimova ◽  
G. L. Buchbinder ◽  
S. V. Kachin

Calibration by the concentration ratio provides better metrological characteristics compared to other calibration modes when using the inductively coupled plasma atomic emission spectrometry (ICP-AES) for analysis of geological samples and technical materials on their base. The main reasons for the observed improvement are: i) elimination of the calibration error of measuring vessels and the error of weighing samples of the analyzed materials from the total error of the analysis; ii) high intensity of the lines of base element; and iii) higher accuracy of measuring the ratio of intensities compared to that of measuring the absolute intensities. Calcium oxide is better suited as a base when using calibration by the concentration ratio in analysis of carbonate rocks, technical materials, slags containing less than 20% SiO2 and more than 20% CaO. An equation is derived to calculate the content of components determined in carbonate materials when using calibration by the concentration ratio. A method of ICP-AES with calibration by the concentration ratio is developed for determination of CaO (in the range of contents 20 – 100%), SiO2 (2.0 – 35%), Al2O3 (0.1 – 30%), MgO (0.1 – 20%), Fe2O3 (0.5 – 40%), Na2O (0.1 – 15%), K2O (0.1 – 5%), P2O5 (0.001 – 2%), MnO (0.01 – 2%), TiO2 (0.01 – 2.0%) in various carbonate materials. Acid decomposition of the samples in closed vessels heated in a HotBlock 200 system is proposed. Correctness of the procedure is confirmed in analysis of standard samples of rocks. The developed procedure was used during the interlaboratory analysis of the standard sample of slag SH17 produced by ZAO ISO (Yekaterinburg, Russia).


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