Biocompatibility of Nanomaterials: Physical and Chemical Properties of Nanomaterials Relevant to Toxicological Studies, In Vitro and In Vivo

2016 ◽  
pp. 691-704
2020 ◽  
pp. 088532822095089
Author(s):  
Yuanxing Zhou ◽  
Xiaochi Ma ◽  
Zhonghai Li ◽  
Bo Wang

An effective and viable hemostatic agent is important for stopping bleeding during surgery. However, it is difficult to achieve hemostasis at uneven or deep bleeding sites using a gelatin sponge. A flowable hemostatic agent has therefore been developed by processing and improving gelatin sponge, to address bleeding under these conditions. In this study, we evaluated the efficacy, safety, and physical and chemical properties of this flowable hemostatic agent in various experiments. We examined its efficacy for stopping bleeding in a rabbit model of liver abrasion in vivo, and compared its efficacy in dynamic coagulation and erythrocyte aggregation tests with gelatin sponge in vitro. We also investigated its safety in rat histocompatibility and acute systemic toxicity tests in mice in vivo, and in hemolysis tests in vitro, to determine if the flowable hemostatic agent induced any pathological reactions or adverse events. In terms of its physical and chemical properties, we analyzed the morphology and chemical bonds of the flowable hemostatic agent by optical and electron microscopy and infrared spectroscopy, and its absorbency and density. The flowable hemostatic agent resulted in a shorter mean bleeding time, less bleeding, greater likelihood of successful hemostasis, and reduced clotting time compared with gelatin sponge. The flowable agent produced some changes in physical morphology, but no pathological changes or undesirable outcomes were detected. This flowable topical hemostatic agent thus provides a safe and more effective hemostatic method than gelatin sponge, and more promising results for intraoperative hemostasis, especially on uneven or deep bleeding surfaces.


Author(s):  
Loredana Stabili ◽  
Roberto Schirosi ◽  
Angela Di Benedetto ◽  
Alessandro Merendino ◽  
Luciano Villanova ◽  
...  

Although mucus plays many different roles among marine invertebrates, relatively little is known about the link between biochemical structure and function. In the present study we focused on some physical and chemical properties of the polychaeteSabella spallanzanii's mucus such as viscosity, osmolarity, electrical conductivity, elemental composition, the protein and carbohydrate content, the total lipids and fatty acid composition, and polychlorinated biphenyls (PCBs) contamination. Moreover, an antimicrobial activity of the mucus was investigated. The water content ofS. spallanzaniimucus was 96.2±0.3%. By dry weight 26±1.2% was protein, 8±0.21% was carbohydrate and only 0.1% lipid, much of the remainder of the dry weight was inorganic (about 65.2%). The estimated PCBs content was <0.005 μg g−1. The mucus ofS. spallanzaniiexerted a natural lysozyme-like activity and producedin vitrothe growth inhibition ofVibrio anguillarum, Vibrio harveyi, Pseudomonas aeruginosaandCandida albicans.The findings from this study contribute to improve the limited knowledge available on the mucus composition in invertebrates and have implications for future investigations related to employment ofS. spallanzaniimucus as a source of compounds of pharmaceutical and marine technological interest.


2018 ◽  
Vol 7 (12) ◽  
pp. 490 ◽  
Author(s):  
Daniel Teleanu ◽  
Cristina Chircov ◽  
Alexandru Grumezescu ◽  
Adrian Volceanov ◽  
Raluca Teleanu

Nanoparticles are zero-dimensional nanomaterials and, based on their nature, they can be categorized into organic, inorganic, and composites nanoparticles. Due to their unique physical and chemical properties, nanoparticles are extensively used in a variety of fields, including medicine, pharmaceutics, and food industry. Although they have the potential to improve the diagnosis and treatment of brain diseases, it is fundamentally important to develop standardized toxicological studies, which can prevent the induction of neurotoxic effects. The focus of this review is to emphasize both the beneficial and negative effects of nanoparticles on brain health.


1969 ◽  
Vol 15 (6) ◽  
pp. 501-507 ◽  
Author(s):  
M. A. Stillwell ◽  
F. A. Wood ◽  
G. M. Strunz

A growth inhibitor with the molecular formula C10H10O4Cl2 was isolated from a medium which had supported growth of a species of Cryptosporiopsis, an imperfect fungus. The compound was named cryptosporiopsin and was characterized on the basis of its physical and chemical properties. Cryptosporiopsin was active in vitro against many wood-rotting basidiomycetes as well as some phycomycetes, ascomycetes, and deuteromycetes. It was more effective than Dithane M-22 or nystatin against the in vitro spore germination of Phytophthora infestans. It was active to varying degrees against six species of bacteria. Cryptosporiopsin was compared with Orbenin and streptomycin against a penicillin-resistant strain of Staphylococcus aureus.


2021 ◽  
Vol 2 ◽  
Author(s):  
Hua Lin ◽  
Cuilan Yin ◽  
Anchun Mo

Zirconia, with its excellent mechanical properties, chemical stability, biocompatibility, and negligible thermal conductivity, is ideal for dental and orthopedic applications. In addition, the biocompatibility of zirconia has been studied in vivo, and no adverse reactions were observed when zirconia samples were inserted into bone. However, their use is controversial among dentists and researchers, especially when compared with mature implants made of titanium alloy. The advantages and limitations of zirconia as biomaterials, such as implant materials, need to be carefully studied, and the design, manufacture, and clinical operation guidelines are urgently required. In this review, the special components, microstructure, mechanical strength, biocompatibility, and the application of zirconia ceramics in biomaterials are detailly introduced. The review highlights discussions on how to implement innovative strategies to design the physical and chemical properties of zirconia so that the treated zirconia can provide better osteointegration after implantation.


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