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Journal of Long-term Effects of Medical... 2018Alumina (Al2O3) ceramic is widely used for medical devices and its biocompatibility is well known and is reported in articles and textbooks. However, finding proof of... (Review)
Review
Alumina (Al2O3) ceramic is widely used for medical devices and its biocompatibility is well known and is reported in articles and textbooks. However, finding proof of this assertion gathered over more than 40 years can be challenging. We performed a literature review about alumina biocompatibility to compile data from the literature. We searched for articles on the biocompatibility of alumina in relation to the ISO 10993-1 International Standard, which defines the biocompatibility of biomaterials. For every biological effect listed in the norm, such as cytotoxicity, sensitization, implantation, and genotoxicity, in vitro and in vivo tests in animals and humans did not reveal any abnormal biological response. Proof for the the well-known biocompatibility of alumina is summarized in this review.
Topics: Aluminum Oxide; Animals; Biocompatible Materials; Humans; Materials Testing
PubMed: 29772987
DOI: 10.1615/JLongTermEffMedImplants.2018025635 -
International Journal of Toxicology Nov 2016This is a safety assessment of alumina and aluminum hydroxide as used in cosmetics. Alumina functions as an abrasive, absorbent, anticaking agent, bulking agent, and... (Review)
Review
This is a safety assessment of alumina and aluminum hydroxide as used in cosmetics. Alumina functions as an abrasive, absorbent, anticaking agent, bulking agent, and opacifying agent. Aluminum hydroxide functions as a buffering agent, corrosion inhibitor, and pH adjuster. The Food and Drug Administration (FDA) evaluated the safe use of alumina in several medical devices and aluminum hydroxide in over-the-counter drugs, which included a review of human and animal safety data. The Cosmetic Ingredient Review (CIR) Expert Panel considered the FDA evaluations as part of the basis for determining the safety of these ingredients as used in cosmetics. Alumina used in cosmetics is essentially the same as that used in medical devices. This safety assessment does not include metallic or elemental aluminum as a cosmetic ingredient. The CIR Expert Panel concluded that alumina and aluminum hydroxide are safe in the present practices of use and concentration described in this safety assessment.
Topics: Aluminum Hydroxide; Aluminum Oxide; Animals; Consumer Product Safety; Cosmetics; Equipment and Supplies; Government Regulation; Humans; Molecular Structure; Toxicity Tests; Toxicokinetics; United States; United States Food and Drug Administration
PubMed: 27913785
DOI: 10.1177/1091581816677948 -
Scientific Reports Feb 2020The knowledge about a potential in vivo uptake and subsequent toxicological effects of aluminum (Al), especially in the nanoparticulate form, is still limited. This...
The knowledge about a potential in vivo uptake and subsequent toxicological effects of aluminum (Al), especially in the nanoparticulate form, is still limited. This paper focuses on a three day oral gavage study with three different Al species in Sprague Dawley rats. The Al amount was investigated in major organs in order to determine the oral bioavailability and distribution. Al-containing nanoparticles (NMs composed of Al and aluminum oxide (AlO)) were administered at three different concentrations and soluble aluminum chloride (AlCl·6HO) was used as a reference control at one concentration. A microwave assisted acid digestion approach followed by inductively coupled plasma mass spectrometry (ICP-MS) analysis was developed to analyse the Al burden of individual organs. Special attention was paid on how the sample matrix affected the calibration procedure. After 3 days exposure, AlCl·6HO treated animals showed high Al levels in liver and intestine, while upon treatment with Al NMs significant amounts of Al were detected only in the latter. In contrast, following AlO NMs treatment, Al was detected in all investigated organs with particular high concentrations in the spleen. A rapid absorption and systemic distribution of all three Al forms tested were found after 3-day oral exposure. The identified differences between Al and AlO NMs point out that both, particle shape and surface composition could be key factors for Al biodistribution and accumulation.
Topics: Administration, Oral; Aluminum; Aluminum Chloride; Aluminum Oxide; Animals; Biological Availability; Humans; Intestines; Liver; Nanostructures; Rats; Rats, Sprague-Dawley; Spleen; Tissue Distribution
PubMed: 32060369
DOI: 10.1038/s41598-020-59710-z -
Biosensors Jul 2023Interferometry-based, reflectometric, label-free biosensors have made significant progress in the analysis of molecular interactions after years of development. The... (Review)
Review
Interferometry-based, reflectometric, label-free biosensors have made significant progress in the analysis of molecular interactions after years of development. The design of interference substrates is a key research topic for these biosensors, and many studies have focused on porous films prepared by top-down methods such as porous silicon and anodic aluminum oxide. Lately, more research has been conducted on ordered porous layer interferometry (OPLI), which uses ordered porous colloidal crystal films as interference substrates. These films are made using self-assembly techniques, which is the bottom-up approach. They also offer several advantages for biosensing applications, such as budget cost, adjustable porosity, and high structural consistency. This review will briefly explain the fundamental components of self-assembled materials and thoroughly discuss various self-assembly techniques in depth. We will also summarize the latest studies that used the OPLI technique for label-free biosensing applications and divide them into several aspects for further discussion. Then, we will comprehensively evaluate the strengths and weaknesses of self-assembly techniques and discuss possible future research directions. Finally, we will outlook the upcoming challenges and opportunities for label-free biosensing using the OPLI technique.
Topics: Porosity; Interferometry; Biosensing Techniques; Silicon; Aluminum Oxide
PubMed: 37504128
DOI: 10.3390/bios13070730 -
Biological Trace Element Research Sep 2022Aluminum oxide nanoparticles (AlONPs) are one class of widely used nanomaterials. However, the teratogenicity toxicity of AlONPs in mammal remains poorly understood....
Aluminum oxide nanoparticles (AlONPs) are one class of widely used nanomaterials. However, the teratogenicity toxicity of AlONPs in mammal remains poorly understood. This study was aimed to evaluate the teratogenicity of AlONPs in Sprague Dawley (SD) rats by gavage and to compare the effects of AlONPs to those of equivalent dose of microscale aluminum oxide (bulk AlO). Sixty pregnant rats were randomly divided into 5 groups and treated with 100 and 200 mg/kg body weight (bw) AlONPs (30 nm), 200 mg/kg bulk AlO, deionized water (as the negative control), and 300 mg/kg aspirin (as the positive control). Rats were exposed daily by oral gavage from the 7 day of gestation for 10 consecutive days and sacrificed on the 20 day of gestation. Results of the study showed that there were no significant effects of AlONPs on pregnant rats (clinical signs, body weight, food consumption, ovary and uterus weight, number of corpora lutea) and fetuses (body weight, sex, body length, tail length, skeletal and visceral development). Under the experimental conditions of the present study, 10 consecutive days of repeated oral administration of AlONPs at doses of up to 200 mg/kg/day did not induce any treatment-related teratogenicity in SD rats. Accordingly, the NOAEL was determined to be 200 mg/kg AlONPs (106 mg Al/kg bw/day) in rats. The teratogenic effects of AlONPs in rats were comparable to those of the bulk AlO of same doses (200 mg/kg).
Topics: Aluminum Oxide; Animals; Body Weight; Female; Fetus; Mammals; Nanoparticles; Pregnancy; Rats; Rats, Sprague-Dawley
PubMed: 34761357
DOI: 10.1007/s12011-021-03004-6 -
Journal of Esthetic and Restorative... May 2024This scoping review aims to assess the influence of air abrasion with aluminum oxide and bioactive glass on dentin bond strength. (Review)
Review
OBJECTIVE
This scoping review aims to assess the influence of air abrasion with aluminum oxide and bioactive glass on dentin bond strength.
MATERIALS AND METHODS
An electronic search was conducted in three databases (PubMed, Cochrane Library, and Embase), on March 3rd, 2023, with previously identified MeSH Terms. A total of 1023 records were screened. Exclusion criteria include primary teeth, air abrasion of a substrate other than sound dentin, use of particles apart from aluminum oxide or bioactive glass, and studies in which bond strength was not assessed.
RESULTS
Out of the 1023 records, title and abstract screening resulted in the exclusion of 895 and 67 studies, respectively, while full-text analysis excluded another 25 articles. In addition, 5 records were not included, as full texts could not be obtained after requesting the authors. Two cross-references were added. Thus, 33 studies were included in this review. It is important to emphasize the absence of standardization of air abrasion parameters. According to 63.6% of the studies, air abrasion does not influence dentin bond strength. Moreover, 30.3% suggest improving bonding performance, and 6.1% advocate a decrease.
CONCLUSIONS
Air abrasion with aluminum oxide does not enhance or impair dentin bond strength. The available data on bioactive glass are limited, which hinders conclusive insights.
CLINICAL SIGNIFICANCE
Dentin air abrasion is a widely applied technique nowadays, with numerous clinical applications. Despite the widespread adoption of this procedure, its potential impact on bonding performance requires a thorough analysis of the existing literature.
Topics: Composite Resins; Dental Bonding; Air Abrasion, Dental; Materials Testing; Surface Properties; Aluminum Oxide; Dentin; Resin Cements
PubMed: 38130045
DOI: 10.1111/jerd.13183 -
Journal of Biomedical Materials... May 2020The use of nanoscale surface modifications offers a possibility to regulate the bacterial adherence behavior. The aim of this study was to evaluate the influence of...
The use of nanoscale surface modifications offers a possibility to regulate the bacterial adherence behavior. The aim of this study was to evaluate the influence of nanoporous anodic aluminum oxide of different pore diameters on the bacterial species Streptococcus mitis and Streptococcus mutans. Nanoporous anodic aluminum oxide (AAO) surfaces with an average pore diameter of 15 and 40 nm, polished pure titanium and compact aluminum oxide (alumina) samples as reference material were investigated. S. mitis and mutans were evaluated for initial adhesion and viability after an incubation period of 30 and 120 min. After 30 min a significantly reduced growth of S. mitis and mutans on 15 nm samples compared to specimens with 40 nm pore diameter, alumina and titanium surfaces could be observed (p < .001). Even after 120 min incubation there was a significant difference between the surfaces with 15 nm pore diameter and the remaining samples (p < .001). AAO surfaces with a small pore diameter have an inhibitory effect on the initial adhesion of S. mitis and mutans. The use of such pore dimensions in the area of the implant shoulder represents a possibility to reduce the adhesion behavior of these bacterial species.
Topics: Aluminum Oxide; Bacterial Adhesion; Electrodes; Porosity; Streptococcus mitis; Streptococcus mutans
PubMed: 31763773
DOI: 10.1002/jbm.b.34514 -
Advances in Protein Chemistry and... 2015Porous aluminum is a nanostructured material characterized by unique properties, such as chemical stability, regular uniformity, dense hexagonal porous lattice with high... (Review)
Review
Porous aluminum is a nanostructured material characterized by unique properties, such as chemical stability, regular uniformity, dense hexagonal porous lattice with high aspect ratio nanopores, excellent mechanical strength, and biocompatibility. This overview examines how the structure and properties of porous alumina can be exploited in the field of public health. Porous alumina can be employed for fabricating membranes and filters for bioremediation, water ultrafiltration, and microfiltration/nanofiltration, being a promising technique for having clean and fresh water, which is essential for human health. Porous alumina-based nanobiosensor coated with specific antibodies or peptides seem to be a useful tool to detect and remove pathogens both in food and in water, as well as for environmental monitoring. Further, these applications, being low-energy demanding and cost-effective, are particularly valuable in resource-limited settings and contexts, and can be employed as point of use devices in developing countries, where there is an urgent need of hygiene and safety assurance.
Topics: Aluminum Oxide; Biocompatible Materials; Biodegradation, Environmental; Environmental Monitoring; Food Microbiology; Humans; Porosity; Public Health; Water Microbiology
PubMed: 26572980
DOI: 10.1016/bs.apcsb.2015.08.003 -
International Journal of Biological... Jul 2018l-asparaginase from Escherichia coli (l-ASNase) was covalently immobilized on aluminum oxide pellets (AlOPs) using a cross-linking agent, glutaraldehyde. Maximum...
l-asparaginase from Escherichia coli (l-ASNase) was covalently immobilized on aluminum oxide pellets (AlOPs) using a cross-linking agent, glutaraldehyde. Maximum immobilization yield (85.0%) was obtained after optimizing immobilization parameters using response surface methodology (RSM). Both free and immobilized l-ASNase (AlOP-ASNase) were optimally active at 37°C and pH7.5. However, the bioconjugate exhibited enhanced activity and stability at different pH and temperatures. It had higher affinity (low K) and was comparatively more stable in presence of some solvents (ethyl acetate, acetone, acetonitrile), metal ions (Ag, Zn) and β-mercaptoethanol. AlOP-ASNase was reused in a glass column reactor for l-asparagine hydrolysis upto nine successive cycles without any loss in activity. The AlOP-ASNase was effective in lowering l-asparagine level in blanched potato chips indicating its potential use in mitigating acrylamide formation in starchy foods. This cost-effective enzyme preparation had shelf-life of more than 30days and can be effectively used in starch based food industries.
Topics: Aluminum Oxide; Asparaginase; Catalysis; Enzymes, Immobilized; Escherichia coli; Escherichia coli Proteins
PubMed: 29572146
DOI: 10.1016/j.ijbiomac.2018.03.081 -
Environmental Science and Pollution... Dec 2023The global "copper-poor and aluminum-rich" situation has made the possibility of "copper saving with aluminum" an important topic. This study established a framework for...
The global "copper-poor and aluminum-rich" situation has made the possibility of "copper saving with aluminum" an important topic. This study established a framework for analyzing multiple substances' coupled flows at the product level based on material flow analysis (MFA), and took the household air conditioning system of the Chinese mainland in 2020 as an example to characterize the coupled flows of aluminum and copper. The results showed that the system consumed 0.69 million tons of aluminum and 2.10 million tons of copper, and discharged 0.17 million tons of aluminum and 0.43 million tons of copper to the environment cumulatively to achieve 13.2 million terajoules of final heat exchanged and serve 1.24 billion square meters during lifetime in mainland China alone, secondary aluminum and copper accounted for only 22.61% and 24.83% of the total consumption, and the in-use stocks increased by 0.19 million tons of aluminum and 0.70 million tons of copper. The external dependency of copper ore was 92.83%, which was significantly higher than the 44.29% of bauxite. The comprehensive utilization efficiency of copper reached 77.88%, which was slightly higher than the 70.80% of aluminum. The conclusion indicates that under the premise of meeting use requirements, promoting "replacing copper with aluminum" can improve the stability and safety of China's material supply chain, but there is a need to further boost the production efficiency of aluminum in primary production.
Topics: Aluminum; Copper; Air Conditioning; China; Aluminum Oxide
PubMed: 37991616
DOI: 10.1007/s11356-023-30861-6