Morphological and chemical stability of silicon nanostructures and their molecular overlayers under physiological conditions: towards long-term implantable nanoelectronic biosensors

The fast and direct detection of small quantities of biological and chemical species is of key importance for numerous biomedical applications. Extensive research has been conducted on nanoelectronic devices that can perform such detection with high sensitivity using silicon nanowires and nanostructures. However, it was recently demonstrated that Si material suffers a lack of long-term stability in physiological environments at nanometer scale [1,2], and is hence not suited for in situ sensing of biological molecules. The results presented here are two important steps toward the realization of core-shell Si-SiC NWFETs for the detection of biomolecules in liquid media. First, we show that SiC NWs exhibit higher chemical stability than Si NWs under physiological conditions. Second, we present the successful carburation of a thin film of Si resulting in a 3.6 nm thin SiC layer.

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Chemical stability of oil-infused polyethylene

Journal of Biomaterials Applications ◽

10.1177/0885328220977353 ◽

2020 ◽

pp. 088532822097735

Author(s):

Fedra P Zaribaf ◽

Harinderjit S Gill ◽

Elise C Pegg

Keyword(s):

Vitamin E ◽

Chemical Stability ◽

Antioxidant Properties ◽

Oxidation Stability ◽

Thermal Ageing ◽

Similar Process ◽

Mechanical Degradation ◽

Suitable Material ◽

Thermally Treated

Ultra-high molecular weight polyethylene (UHMWPE) can be made radiopaque for medical imaging applications through the diffusion of an iodised oil-based contrast agent (Lipiodol Ultra Fluid). A similar process is used for Vitamin E incorporated polyethylene which provides antioxidant properties. This study aimed to investigate the critical long-term properties of oil-infused medical polyethylene after 4 weeks of accelerated thermal ageing. Samples treated with an oil (Vitamin E or Lipiodol) had a higher oxidation stability than currently used medical grade polyethylene, indicated by a smaller increase in oxidation index after ageing (Vitamin E + 36%, Lipiodol +40%, Untreated +136%, Thermally treated +164%). The tensile properties of oil treated polyethylene after ageing were significantly higher than the Untreated and Thermally treated controls (p<0.05) indicating less mechanical degradation. There was also no alteration in the percentage crystallinity of oil treated samples after ageing, though the radiopacity of the Lipiodol treated samples reduced by 54% after ageing. The leaching of oil with time was also investigated; the leaching of Lipiodol and Vitamin E followed the same trend and reached a steady state by two weeks. Overall, it can be concluded that the diffusion of an oil-based fluid into polyethylene not only increases the oxidative and chemical stability of polyethylene but also adds additional functionality (e.g. radiopacity) providing a more suitable material for long–term medical applications.

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Long-Term Structural and Chemical Stability of Carbon Electrodes in Vanadium Redox Flow Battery

ACS Applied Energy Materials ◽

10.1021/acsaem.1c00912 ◽

2021 ◽

Author(s):

Bhuvaneswari M. Sivakumar ◽

Venkateshkumar Prabhakaran ◽

Kaining Duanmu ◽

Edwin Thomsen ◽

Brian Berland ◽

...

Keyword(s):

Chemical Stability ◽

Vanadium Redox Flow Battery ◽

Carbon Electrodes ◽

Redox Flow Battery ◽

Flow Battery ◽

Vanadium Redox

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Chemical stability and long-term cell performance of low-cobalt, Ni-Rich cathodes prepared by aqueous processing for high-energy Li-Ion batteries

Energy Storage Materials ◽

10.1016/j.ensm.2019.08.020 ◽

2020 ◽

Vol 24 ◽

pp. 188-197 ◽

Cited By ~ 30

Author(s):

Marissa Wood ◽

Jianlin Li ◽

Rose E. Ruther ◽

Zhijia Du ◽

Ethan C. Self ◽

...

Keyword(s):

Chemical Stability ◽

High Energy ◽

Cell Performance ◽

Li Ion Batteries ◽

Aqueous Processing ◽

Li Ion

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Cancer Nano-Immunotherapy from the Injection to the Target: The Role of Protein Corona

International Journal of Molecular Sciences ◽

10.3390/ijms21020519 ◽

2020 ◽

Vol 21 (2) ◽

pp. 519

Author(s):

Idoia Mikelez-Alonso ◽

Antonio Aires ◽

Aitziber L. Cortajarena

Keyword(s):

Protein Corona ◽

Biological Properties ◽

Immune Reactivity ◽

Target Tissue ◽

Physiological Conditions ◽

Different Types ◽

Cancer Remission ◽

New Strategies

Immunotherapy has become a promising cancer therapy, improving the prognosis of patients with many different types of cancer and offering the possibility for long-term cancer remission. Nevertheless, some patients do not respond to these treatments and immunotherapy has shown some limitations, such as immune system resistance or limited bioavailability of the drug. Therefore, new strategies that include the use of nanoparticles (NPs) are emerging to enhance the efficacy of immunotherapies. NPs present very different pharmacokinetic and pharmacodynamic properties compared with free drugs and enable the use of lower doses of immune-stimulating molecules, minimizing their side effects. However, NPs face issues concerning stability in physiological conditions, protein corona (PC) formation, and accumulation in the target tissue. PC formation changes the physicochemical and biological properties of the NPs and in consequence their therapeutic effect. This review summarizes the recent advances in the study of the effects of PC formation in NP-based immunotherapy. PC formation has complex effects on immunotherapy since it can diminish (“immune blinding”) or enhance the immune response in an uncontrolled manner (“immune reactivity”). Here, future perspectives of the field including the latest advances towards the use of personalized protein corona in cancer immunotherapy are also discussed.

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Genome flux in tomato cell clones cultured in vitro in different physiological equilibria. II. A RAPD analysis of variability

Genome ◽

10.1139/g96-107 ◽

1996 ◽

Vol 39 (5) ◽

pp. 846-853 ◽

Cited By ~ 26

Author(s):

Patrizia Bogani ◽

Alessandra Simoni ◽

Pietro Lio' ◽

Angela Scialpi ◽

Marcello Buiatti

Keyword(s):

Rapd Analysis ◽

Cell Populations ◽

Physiological Conditions ◽

Active Defense ◽

Cell Clones ◽

Pattern Correlation ◽

Key Words Tomato ◽

High Competence

An analysis of the effect of changing physiological conditions on genome evolution in tomato cell populations has been carried out on long-term in vitro cultured clones grown on different auxin–cytokinin equilibria or selected for low–high competence for active defense against Fusarium oxysporum f.sp. lycopersici. RAPD analysis, confirmed through pattern rehybridization, was used as a random tool to measure the genetic variability. Through the use of a modified ANOVA, variation was shown to depend on both the initial genotype and the physiological conditions. Pattern correlation analysis through a mutual information algorithm suggested the fixation of RAPD patterns specific to physiological equilibria. The results are discussed in view of the possible relevance for evolution at hierarchical levels higher than cell populations. Key words : tomato clones, somaclonal variation, RAPD, coadaptation.

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