Silver nanoparticles (AgNPs) have tremendous potentials in medical devices due to their excellent antimicrobial properties. Blood compatibility should be investigated for AgNPs due to the potential blood contact. However, so far, most studies are not systematic and have not provided insights into the mechanisms for blood compatibility of AgNPs. In this study, we have investigated the blood biological effects, including hemolysis, lymphocyte proliferation, platelet aggregation, coagulation and complement activation, of 20 nm AgNPs with two different surface coatings (polyvinyl pyrrolidone and citrate). Our results have revealed AgNPs could elicit hemolysis and severely impact the proliferation and viability of lymphocytes at all investigated concentrations (10, 20, 40 μg/mL). Nevertheless, AgNPs didn’t show any effect on platelet aggregation, coagulation process, or complement activation at up to ~40 μg/mL. Proteomic analysis on AgNPs plasma proteins corona has revealed that acidic and small molecular weight blood plasma proteins were preferentially adsorbed onto AgNPs, and these include some important proteins relevant to hemostasis, coagulation, platelet, complement activation and immune responses. The predicted biological effects of AgNPs by proteomic analysis are mostly consistent with our experimental data since there were few C3 components on AgNPs and more negative than positive factors involving platelet aggregation and thrombosis.

We present a wavelength tunable absorber composed of periodically patterned cross-shaped graphene arrays in the far-infrared and THz regions. The absorption of the single-layer array can essentially exceed the continuous graphene sheet by increasing the cross-arm width, even for small graphene filling ratio. As chemical potential and relaxation time increase, the absorption can be significantly enhanced. The complementary structure shows higher absorption compared to the original graphene array. Moreover, the wavelength of absorption maximum is angle-insensitive for both TE and TM polarizations. The absorption efficiency can be further improved with double layers of the cross-shaped graphene arrays, which are helpful to design dual-band and broadband absorbers.

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A B S T R A C TConsidering the harmful effects of volatile organic compounds (VOCs) on the atmosphere and public health, the search for proper catalytic materials for the effective catalytic elimination of VOCs remains one of the most pressing issues in the environmental field. In this study, a series of mesoporous Co 3 O 4 -n (n = 0.00, 0.0001, 0.01, 0.05, 0.10, 1.00, representing the concentration of HNO 3 aqueous solution) catalysts were fabricated by the acid treatment of Co 3 O 4 that was previously prepared via a hydroxycarbonate precipitation method (Co 3 O 4 -P). The catalytic performances of the prepared catalysts were evaluated for the model reaction of toluene oxidation. An obvious enhancement of catalytic activity in the reaction was achieved over the acid-treated Co 3 O 4 catalysts using lower HNO 3 concentrations, with Co 3 O 4 -0.01 exhibiting the optimum catalytic activity (T 90 = 225°C, 15°C lower than that of Co 3 O 4 -P), excellent catalytic durability under dry conditions and a high regeneration capability under humid conditions. Benefitting from the dilute acid treatment, the Co 3 O 4 -n (n = 0.01, 0.05, 0.10) catalysts presented higher specific surface areas, more weak acidic sites and higher abundances of surface Co 2+ and O ads species, which were regarded as the key factors responsible for their enhanced catalytic activities.

The emergence of antibiotic resistant bacteria is a major threat to the practice of modern medicine. Photobactericidal agents have obtained significant attention as promising candidates to kill bacteria, and they have been extensively studied. However, to obtain photobactericidal activity, an intense white light source or UV-activation is usually required. Here we report a photobactericidal polymer containing crystal violet (CV) and thiolated gold nanocluster ([Au 25 (Cys) 18 ]) activated at a low flux levels of white light. It was shown that the polymer encapsulated with CV do not have photobactericidal activity under white light illumination of an average 312 lux. However, encapsulation of [Au 25 (Cys) 18 ] and CV into the polymer activates potent photobactericidal activity. The study of the photobactericidal mechanism shows that additional encapsulation of [Au 25 (Cys) 18 ] into the CV treated polymer promotes redox reactions through generation of alternative electron transfer pathways, while it reduces photochemical reaction type-ІІ pathways resulting in promotion of hydrogen peroxide (H 2 O 2) production.

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Simultaneous on-chip sensing of multiple greenhouse gases in a complex gas environment is highly desirable in industry, agriculture, and meteorology, but remains challenging due to their ultralow concentrations and mutual interference. Porous microstructure and extremely high surface areas in metal-organic frameworks (MOFs) provide both excellent adsorption selectivity and high gases affinity for multigas sensing. Herein, it is described that integrating MOFs into a multiresonant surface-enhanced infrared absorption (SEIRA) platform can overcome the shortcomings of poor selectivity in multigas sensing and enable simultaneous on-chip sensing of greenhouse gases with ultralow concentrations. The strategy leverages the near-field intensity enhancement (over 1500-fold) of multiresonant SEIRA technique and the outstanding gas selectivity and affinity of MOFs. It is experimentally demonstrated that the MOF-SEIRA platform achieves simultaneous on-chip sensing of CO 2 and CH 4 with fast response time (<60 s), high accuracy (CO 2 : 1.1%, CH 4 : 0.4%), small footprint (100 × 100 µm 2), and excellent linearity in wide concentration range (0-2.5 × 10 4 ppm). Additionally, the excellent scalability to detect more gases is explored. This work opens up exciting possibilities for the implementation of all-in-one, real-time, and on-chip multigas detection as well as provides a valuable toolkit for greenhouse gas sensing applications.

Plasmonic metal nanoparticles have extinction cross sections surpassing their physical cross sections, enabling them to act as a powerful intermediary for enhancing light−matter interactions.