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1.
Nat Mater ; 22(12): 1548-1555, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37723337

RESUMO

Aerophilic surfaces immersed underwater trap films of air known as plastrons. Plastrons have typically been considered impractical for underwater engineering applications due to their metastable performance. Here, we describe aerophilic titanium alloy (Ti) surfaces with extended plastron lifetimes that are conserved for months underwater. Long-term stability is achieved by the formation of highly rough hierarchically structured surfaces via electrochemical anodization combined with a low-surface-energy coating produced by a fluorinated surfactant. Aerophilic Ti surfaces drastically reduce blood adhesion and, when submerged in water, prevent adhesion of bacteria and marine organisms such as barnacles and mussels. Overall, we demonstrate a general strategy to achieve the long-term stability of plastrons on aerophilic surfaces for previously unattainable underwater applications.

2.
Adv Sci (Weinh) ; 9(25): e2202803, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35780494

RESUMO

Utilizing ionizing radiation for in situ studies in liquid media enables unique insights into nanostructure formation dynamics. As radiolysis interferes with observations, kinetic simulations are employed to understand and exploit beam-liquid interactions. By introducing an intuitive tool to simulate arbitrary kinetic models for radiation chemistry, it is demonstrated that these models provide a holistic understanding of reaction mechanisms. This is shown for irradiated HAuCl4 solutions allowing for quantitative prediction and tailoring of redox processes in liquid-phase transmission electron microscopy (LP-TEM). Moreover, it is demonstrated that kinetic modeling of radiation chemistry is applicable to investigations utilizing X-rays such as X-ray diffraction (XRD). This emphasizes that beam-sample interactions must be considered during XRD in liquid media and shows that reaction kinetics do not provide a threshold dose rate for gold nucleation relevant to LP-TEM and XRD. Furthermore, it is unveiled that oxidative etching of gold nanoparticles depends on both, precursor concentration, and dose rate. This dependency is exploited to probe the electron beam-induced shift in Gibbs free energy landscape by analyzing critical radii of gold nanoparticles.


Assuntos
Nanopartículas Metálicas , Nanoestruturas , Ouro/química , Nanopartículas Metálicas/química , Microscopia Eletrônica de Transmissão , Difração de Raios X
3.
Mater Sci Eng C Mater Biol Appl ; 95: 275-285, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30573250

RESUMO

An ultrasonication treatment is developed as an external method to control the degradation behavior of pure iron. Immersion tests (weight loss measurements) and electrochemical measurements were conducted in two different pseudo-physiological solutions, simulated body fluid (SBF) and Dulbecco's modified Eagle medium (DMEM) solution. By the comparison study in these two different solutions, more information and the mechanism of the degradation process can be revealed. Degradation morphologies (with and without ultrasonication treatment) were observed by scanning electron microscope (SEM), and degradation products on the surface were characterized by Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS). Moreover, the biocompatibility of iron surfaces after being ultrasonicated was evaluated. Ultrasonication was found to accelerate the degradation rate in DMEM, while it makes no difference in SBF solution; the origin of this different behavior is investigated and discussed. The parameters of the ultrasonication treatment, intensity and frequency, show an influence on the degradation rate. No adverse effects on the proliferation and adhesion of human osteoblast-like cells (MG-63) are observed on surfaces after ultrasonication treatment, as compared to bare iron. Based on these results, ultrasonication treatment is considered to have high potential to control the biodegradation behavior of iron-based materials in an external and flexible manner.


Assuntos
Ferro/química , Soluções/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Microscopia Eletrônica de Varredura , Espectroscopia Fotoeletrônica , Espectroscopia de Infravermelho com Transformada de Fourier
4.
Gastroenterol Nurs ; 40(1): 56-62, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28134720

RESUMO

Transmission of carbapenem-resistant Enterobacteriaceae (CRE) via duodenoscopes, specialized endoscopes used during endoscopic retrograde cholangiopancreatography (ERCP) procedures, has attracted media attention since early 2015. This attention has placed increasing focus on the reprocessing of duodenoscopes. Current reprocessing recommendations for these endoscopes require either high-level disinfection or ethylene oxide sterilization. While reprocessing duodenoscopes, staff at endoscopy locations within the Mercy health system perform a single high-level disinfection cycle that is preceded by two cycles of manual cleaning. The Mercy system has 37 locations for gastrointestinal endoscopic procedures and nine that can accommodate patients requiring ERCP. In early 2016, the Mercy Oklahoma City location performed an ERCP on a patient known prior to the case to be a carrier of CRE. After the case, multiple departments located in both the Oklahoma City and St. Louis facilities partnered to culture and sterilize the duodenoscope used in that case to ensure its safety for use on subsequent patients. This case study presents the situation and discusses culturing of endoscopes. In light of the evidence presented, the importance of enhanced communication and cooperation to achieve patient safety should be paramount to all other factors.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Infecção Hospitalar/epidemiologia , Duodenoscópios/microbiologia , Infecções por Enterobacteriaceae/transmissão , Enterobacteriaceae/isolamento & purificação , Contaminação de Equipamentos/prevenção & controle , Carbapenêmicos/administração & dosagem , Colangiopancreatografia Retrógrada Endoscópica/instrumentação , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana , Duodenoscopia/efeitos adversos , Duodenoscopia/instrumentação , Enterobacteriaceae/efeitos dos fármacos , Feminino , Humanos , Incidência , Masculino , Avaliação das Necessidades , Medição de Risco
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