Silver Nanoclusters Hydrogel For Tableware Disinfection And Drug Delivery

The nanomaterials have attracted a great deal of attention since the 1980 s and been widely used in various fields. Silver nanoclusters, an important part of nanomaterials, has been extensively used in biological sensing, optics and biomedicine due to its unique antibacterial properties, optical properties and catalytic properties. Silver nanoclusters is a broad spectrum antimicrobial and many bacterial strains are susceptible to them, however resistance to other common antimicrobial. Therefore silver nanoclusters has gained some popularity in food packaging, food preservation and tableware disinfection. They can effectively reduce bacterial contamination of food and tableware. Incorporating silver nanoclusters into hydrogels to make nanocomposites can improve their similarity of the biological systems. Silver nanoclusters hydrogel can hold on the basis of shape and absorb large amounts of water or biological fluids. As silver nanoclusters hydrogel is sensitive to temperature, pH and forces, it has a good prospect in biosensor, tissue engineering, drug delivery and so on. However, there is no unified conclusion about the safety of silver nanomaterials. Because distinct synthetic materials and methods result in differences in the properties of silver nanomaterials. This paper focuses on exploring the acute toxicity of silver nanoclusters hydrogel for applications in tableware disinfection and drug delivery.The main contents include:(1) The vitro cytotoxicity of silver nanoclusters hydrogel against two kinds of human cancer cells, human breast cancer cells(MCF-7) and human cervical cancer cells(HeLa), was evaluated by using the methyl thiazolyl tetrazolium assay(MTT).The acute oral toxicity of silver nanoclusters hydrogel was evaluated by using the maximum tolerated experiment and its oral half lethal dose(LD50) was obtained. The antibacterial activity of silver nanoclusters hydrogel against the bacterial in the chopping block was conducted using zones of inhibition, killing logarithm value, and antibacterial effect. The results demonstrated that the half maximal inhibitory concentration(IC50) of MCF-7 and HeLa occurred at 35.91, 24.98, 17.67 μg/m L and 42.13, 28.48, 22.54 μg/mL, respectively after 24 h, 48 h and 72 h exposure to silver nanoclusters hydrogel. After once administration 20 g/kg silver nanoclusters hydrogel, no any poisoning or death was noted in the mice during 14 days. The LD50 of silver nanoclusters hydrogel exceeded 5000 mg/kg in mice. The size of the inhibition zone was 3 mm, and the antibacterial efficiency of silver nanoclusters hydrogel met the national standard as the killing logarithm value was 1.25, which was greater than 1.00 in national standard during 0.5 h. And silver nanoclusters hydrogel was gelatinous and convenient for using, and washing.(2) To examine the acute dermal toxicity of silver nanoclusters hydrogel, mice were subcutaneously injected with silver nanoclusters hydrogel. Then silver nanoclusters hydrogel as a carrier for doxorubicin hydrochloride(DOX·HCl@AgNCs-H), and the release behavior of DOX·HCl@AgNCs-H was investigated in physiological environments by dialysis. The DOX·HCl@AgNCs-H was subcutaneously injected into breast tumor bearing mice to evaluate the tumor inhibition efficacy. And the tumor inhibition efficacy was accessed by analysising body weight, tumor volume, tumor weight and tissue sections. The results demonstrated that the hydrogel was nontoxic at the administered dose of up to 8 g/kg. The drug accumulation release of DOX·HCl@AgNCs-H was 41.21% after 10 h while the release of the DOX·HCl solution was 97.35%. The tumor inhibition efficacy of DOX·HCl@AgNCs-H was 1.66 times higher and the main toxic effect on heart was depressed comparing with that of DOX·HCl solution.