A Bulk Oxygen Vacancy Dominating WO3-x Photocatalyst for Carbamazepine Degradation.

Creating oxygen vacancy in tungsten trioxide (WO3) has been considered as an effective strategy to improve the photocatalytic performance for degrading organic pollutants. In this study, oxygen vacancies were introduced into WO3 by thermal treatment under Ar atmosphere and their proportion was changed by setting different treatment times. WO3-x samples show better photoelectric properties and photocatalytic degradation performance for carbamazepine (CBZ) than an oxygen-vacancy-free sample, and WO3-x with the optimal proportion of oxygen vacancies is obtained by thermal treatment for 3 h in 550 °C. Furthermore, it discovers that the surface oxygen vacancies on WO3-x would be recovered when it is exposed to air, resulting in a bulk oxygen vacancy dominating WO3-x (bulk-WO3-x). The bulk-WO3-x exhibited much higher degradation efficiency for CBZ than WO3-x with both surface and bulk oxygen vacancies. The mechanism study shows bulk-WO3-x mainly degrades the CBZ by producing OH radicals and superoxide radicals, while oxygen-vacancy-free sample mainly oxidizes the CBZ by the photoexcited hole, which requires the CBZ to be adsorbed on the surface for degradation. The radical generated by bulk-WO3-x exhibits stronger oxidizing capacity by migrating to the solution for CBZ degradation. In summary, the influence of oxygen vacancy on photocatalytic degradation performance depends on both the proportion and location distribution and could lie in the optimization of the photodegradation mechanism. The results of this study could potentially broaden our understanding of the role of oxygen vacancies and provide optimal directions and methods for oxygen vacancy regulation for photocatalysts.

Ultrasensitive Graphene Field-Effect Biosensors Based on Ferroelectric Polarization of Lithium Niobate for Breast Cancer Marker Detection.

Herein, we present a novel ultrasensitive graphene field-effect transistor (GFET) biosensor based on lithium niobate (LiNbO3) ferroelectric substrate for the application of breast cancer marker detection. The electrical properties of graphene are varied under the electrostatic field, which is generated through the spontaneous polarization of the ferroelectric substrate. It is demonstrated that the properties of interface between graphene and solution are also altered due to the interaction between the electrostatic field and ions. Compared with the graphene field-effect biosensor based on the conventional Si/SiO2 gate structure, our biosensor achieves a higher sensitivity to 64.7 mV/decade and shows a limit of detection down to 1.7 fM (equivalent to 12 fg·mL-1) on the detection of microRNA21 (a breast cancer marker). This innovative design combining GFETs with ferroelectric substrates holds great promise for developing an ultrahigh-sensitivity biosensing platform based on graphene that enables rapid and early disease diagnosis.

Polyethylene Glycol Functionalized Silicon Nanowire Field-Effect Transistor Biosensor for Glucose Detection.

Accurate monitoring of blood glucose levels is crucial for the diagnosis of diabetes patients. In this paper, we proposed a simple "mixed-catalyzer layer" modified silicon nanowire field-effect transistor biosensor that enabled direct detection of glucose with low-charge in high ionic strength solutions. A stable screening system was established to overcome Debye screening effect by forming a porous biopolymer layer with polyethylene glycol (PEG) modified on the surface of SiNW. The experimental results show that when the optimal ratio (APTMS:silane-PEG = 2:1) modified the surface of silicon nanowires, glucose oxidase can detect glucose in the concentration range of 10 nM to 10 mM. The sensitivity of the biosensor is calculated to be 0.47 µAcm-2mM-1, its fast response time not exceeding 8 s, and the detection limit is up to 10 nM. This glucose sensor has the advantages of high sensitivity, strong specificity and fast real-time response. Therefore, it has a potential clinical application prospect in disease diagnosis.

Acrylamide Hydrogel-Modified Silicon Nanowire Field-Effect Transistors for pH Sensing.

In this study, we report a pH-responsive hydrogel-modified silicon nanowire field-effect transistor for pH sensing, whose modification is operated by spin coating, and whose performance is characterized by the electrical curve of field-effect transistors. The results show that the hydrogel sensor can measure buffer pH in a repeatable and stable manner in the pH range of 3-13, with a high pH sensitivity of 100 mV/pH. It is considered that the swelling of hydrogel occurring in an aqueous solution varies the dielectric properties of acrylamide hydrogels, causing the abrupt increase in the source-drain current. It is believed that the design of the sensor can provide a promising direction for future biosensing applications utilizing the excellent biocompatibility of hydrogels.

[Effect of lingdankang composite combined dendritic cell-cytokine induced killer cells in treating leukemia].

OBJECTIVE: To evaluate the effect and safety of Chinese herbal medicine Lingdankang Composite (LDK) combined dendritic cell-cytokine induced killer cells (DC-CIK) in treating leukemia. METHODS: Subjects were selected from leukemia patients who achieved hematological complete remission (HCR) but not achieved molecular biological remission (MBR), or with minimal residual leukemia (MRL) positive. Twenty patients, 19 of acute leukemia and 1 of chronic myelocytic leukemia, were enrolled. DC and CIK from patient's peripheral blood monocyte were separated respectively by blood cell separator, then DC-CIK was obtained through respective culture followed with mixed cultivation of them, and was infused back to the patient self via intravenous injection. The back infusion of DC-CIK was performed once every 15-20 days for 4-6 times in total. Meantime, LDK was administered orally every day. RESULTS: In the 20 patients treated, 4 case of HCR achieved MBR, the negatively reversed marker gene was AML1/ETO in 1 case, CBFbeta/MYH11 in 1, bcr/abl in 1, and the other 1 was IgH gene rearrangement; 3 patients with positive MRL were reversed to negative. The 3-year CR rate was 75% with a medium CR period of 25 months (10-37 months). Except transient fever and chill in 5 cases, no other remarkable adverse reaction happened during or after DC-CIK infusion. CONCLUSION: The combined treatment of LDK and autologous DC-CIK in treating patients with HCR shows an obvious effect of clearing MRL, it is the appropriate choice for curing leukemia of HCR, and is safety for intravenous infusion, so it has potential clinical prospect.