Toxicological evaluation of silver nanoparticles and silver nitrate in rats following 28 days of repeated oral exposure

2016 ◽  
Vol 32 (2) ◽  
pp. 609-618 ◽  
Author(s):  
Guangqiu Qin ◽  
Song Tang ◽  
Shibin Li ◽  
Haoliang Lu ◽  
Yanwu Wang ◽  
...  
2019 ◽  
Vol 29 (3) ◽  
Author(s):  
Mai Ngọc Tuan Anh

Silver nanoplates (SNPs) having different size were synthesized by a seed-mediated method. The seeds -silver nanoparticles with 4 – 6 nm diameters were synthesized first by reducing silver nitrate with sodium borohydride in the present of Trisodium Citrate and Hydrogen peroxide. Then these seeds were developed by continue reducing Ag\(^+\) ions with various amount of L-Ascorbic acid to form SNPs. Our analysis showed that the concentratrion of L-Ascorbic acid, a secondary reducing agent, played an important role to form SNPs. In addition, the size and in-plane dipole plasmon resonance wavelenght of silver nanoplates were increased when the concentration of added silver nitrate increased. The characterization of SNPs were studied by UV-Vis, FE-SEM, EDS and TEM methods.


2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Hamed Nosrati ◽  
Manijeh Hamzepoor ◽  
Maryam Sohrabi ◽  
Massoud Saidijam ◽  
Mohammad Javad Assari ◽  
...  

Abstract Background Silver nanoparticles (AgNPs) can accumulate in various organs after oral exposure. The main objective of the current study is to evaluate the renal toxicity induced by AgNPs after repeated oral exposure and to determine the relevant molecular mechanisms. Methods In this study, 40 male Wistar rats were treated with solutions containing 30, 125, 300, and 700 mg/kg of AgNPs. After 28 days of exposure, histopathological changes were assessed using hematoxylin-eosin (H&E), Masson’s trichrome, and periodic acid-Schiff (PAS) staining. Apoptosis was quantified by TUNEL and immunohistochemistry of caspase-3, and the level of expression of the mRNAs of growth factors was determined using RT-PCR. Results Histopathologic examination revealed degenerative changes in the glomeruli, loss of tubular architecture, loss of brush border, and interrupted tubular basal laminae. These changes were more noticeable in groups treated with 30 and 125 mg/kg. The collagen intensity increased in the group treated with 30 mg/kg in both the cortex and the medulla. Apoptosis was much more evident in middle-dose groups (i.e., 125 and 300 mg/kg). The results of RT-PCR indicated that Bcl-2 and Bax mRNAs upregulated in the treated groups (p < 0.05). Moreover, the data related to EGF, TNF-α, and TGF-β1 revealed that AgNPs induced significant changes in gene expression in the groups treated with 30 and 700 mg/kg compared to the control group. Conclusion Our observations showed that AgNPs played a critical role in in vivo renal toxicity.


2014 ◽  
Vol 466-467 ◽  
pp. 232-241 ◽  
Author(s):  
Fabianne Ribeiro ◽  
Julián Alberto Gallego-Urrea ◽  
Kerstin Jurkschat ◽  
Alison Crossley ◽  
Martin Hassellöv ◽  
...  

Nanomaterials ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 96
Author(s):  
John Jackson ◽  
Helen Burt ◽  
Dirk Lange ◽  
In Whang ◽  
Robin Evans ◽  
...  

The prompt treatment of burn wounds is essential but can be challenging in remote parts of Africa, where burns from open fires are a constant hazard for children and suitable medical care may be far away. Consequently, there is an unmet need for an economical burn wound dressing with a sustained antimicrobial activity that might be manufactured locally at low cost. This study describes and characterizes the novel preparation of a silver nitrate-loaded/poly(vinyl alcohol) (PVA) film. Using controlled heating cycles, films may be crosslinked with in situ silver nanoparticle production using only a low heat oven and little technical expertise. Our research demonstrated that heat-curing of PVA/silver nitrate films converted the silver to nanoparticles. These films swelled in water to form a robust, wound-compatible hydrogel which exhibited controlled release of the antibacterial silver nanoparticles. An optimal formulation was obtained using 5% (w/w) silver nitrate in PVA membrane films that had been heated at 140 °C for 90 min. Physical and chemical characterization of such films was complemented by in vitro studies that confirmed the effective antibacterial activity of the released silver nanoparticles against both gram positive and negative bacteria. Overall, these findings provide economical and simple methods to manufacture stable, hydrogel forming wound dressings that release antibiotic silver over prolonged periods suitable for emergency use in remote locations.


2018 ◽  
Vol 772 ◽  
pp. 73-77
Author(s):  
Ruelson S. Solidum ◽  
Arnold C. Alguno ◽  
Rey Capangpangan

We report on the green synthesis of silver nanoparticles utilizing theP.purpureumleaf extract. Controlling the surface plasmon absorption of silver nanoparticles was achieved by regulating the amount of extract concentration and the molarity of silver nitrate solution. The surface plasmon absorption peak is found at around 430nm. The surface plasmon absorption peak have shifted to lower wavelength as the amount of extract is increased, while plasmon absorption peak shifts on a higher wavelength as the concentration of silver nitrate is increased before it stabilized at 430nm. This can be explained in terms of the available nucleation sites promoted by the plant extract as well as the available silver ions present in silver nitrate solution.


2021 ◽  
Vol 37 (2) ◽  
pp. 126-133
Author(s):  
O.O Elekofehinti ◽  
M.O Akinjiyan

Hyperlipidemia and hyperglycemia have been implicated in diabetes mellitus (DM) leading to complications such as nephropathy. Medicinal plants like Mormodica charantia (MC) have been used in the treatment of DM over the years but little is known about their mechanisms of action. This study used biotechnology tools to investigate and compare the effects of M. charantia silver nanoparticles (MCSNPs) with M. charantia extract on expressions of genes linked with nephrotoxicity, lipid and glucose metabolisms using reverse-transcriptase polymerase chain reaction (RT-PCR) in streptozotocin-induced diabetic rats. The genes investigated include kidney injury molecule-1 (KIM-1), 3-hydroxyl, 3-methyl glutaryl_coA reductase (HMG-CoA reductase), peroxisome proliferator-activated receptor alpha and gamma (PPARα and PPARγ). Synthesis of MCSNPs was done using 1 mM concentration of aqueous silver nitrate solution at ratio 1:9 (v/v). Experimental rats were induced intraperitoneally with streptozotocin (65 mg/kg) and divided into six groups viz: diabetic control; normal control; silver nitrate (10 mg/kg); MCSNPs (50 mg/kg); Metformin (100 mg/kg) and M. charantia fraction (100 mg/kg). Sacrifice was done after 12 days of treatment and RT-PCR was then used to investigate gene expressions in liver and kidney tissues of the rats. The expression of HMG-CoA reductase gene was significantly upregulated (p<0.05) upon treatment with 50 mg/kg MCSNPs relative to the diabetic untreated group. M. charantia extracts and MCSNPs significantly upregulate (p<0.05) the expressions of PPAR-α and PPAR-γ compared to the diabetic control. Also, a significant (p<0.05) down-regulation of KIM-1 mRNA expression was observed in MCSNPs- treated group, relative to the diabetes untreated group. M. charantia silver nanoparticles could be a potent antidiabetic agent due to its potential to modulate genes associated with lipid metabolism and nephrotoxicity. Keywords: Medicinal plant; Diabetes Mellitus; Silver Nanoparticles; nephrotoxicity; gene expression


2018 ◽  
Vol 18 (3) ◽  
pp. 421 ◽  
Author(s):  
Dian Susanthy ◽  
Sri Juari Santosa ◽  
Eko Sri Kunarti

A study to examine the performance of p-aminobenzoic acid as both reducing agent for silver nitrate to silver nanoparticles (AgNPs) and stabilizing agent for the formed AgNPs has been done. The synthesis of AgNPs was performed by mixing silver nitrate solution as precursor with p-aminobenzoic acid solution and heating it in a boiling water bath. After the solution turned to yellow, the reaction stopped by cooling it in tap water. The formed AgNPs were analyzed by using UV-Vis spectrophotometry to evaluate their SPR absorption in wavelength range of 400–500 nm. The synthesis process was highly depend on the pH, reaction time, and mole ratios of the reactants. The synthesis only occur in pH 11 and at reaction time 30 min, the particle size of the formed AgNPs was 12 ± 7 nm. Longer reaction time increased the reducing performance of p-aminobenzoic acid in AgNPs synthesis but decreased its stabilizing performance. The increase of silver nitrate amount relative to p-aminobenzoic acid in the synthesis increased the reducing and stabilizing performance of p-aminobenzoic acid and the optimum mole ratio between AgNO3 and p-aminobenzoic acid was 5:100 (AgNO3 to p-aminobenzoic acid).


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