Fe and Co-doped (Ba, Ca)TiO3 Perovskite as Potential Electrocatalysts for Glutamate Sensing

Barium titanate (BaTiO3) and calcium titanate (CaTiO3) are renown perovskite-structured dielectric materials. Nevertheless, utilization of BaTiO3 and CaTiO3 in sensing applications has not been extensive. This study, therefore, aims at examining potential usage of BaTiO3 and CaTiO3 as enzyme-less sensors.  BaTiO3, CaTiO3, Fe-doped BaTiO3, Co-doped BaTiO3, Fe-doped BaTiO3, and Co-doped CaTiO3 (with Fe and Co 5 at%) were synthesized by solution combustion technique, compositionally and microstructurally examined, and tested for their electrocatalytic activities. All powders consisted of submicrometer-sized particles. Measurements of electrocatalytic activities in 0.01 M glutamate solution by cyclic voltammetry were performed. It was found that oxidation peaks occurred at applied voltage close to 0.6 V. Peak currents, which denoted electrocatalytic performance, were prominent in doped powders. Electrocatalytic activities of the powders were discussed with respect to chemical composition, microstructure, and electronic characteristic of the materials

Implantable CMOS Biomedical Devices

The results of recent research on our implantable CMOS biomedical devices are reviewed. Topics include retinal prosthesis devices and deep-brain implantation devices for small animals. Fundamental device structures and characteristics as well as in vivo experiments are presented

再発性甲状腺癌のリンパ節転移におけるTc-99m MDPの集積(Tc-99m MDP Accumulation in Lymph Node Metastases of Recurrent Thyroid Cancer)(英語)

金沢医科大学 放射線科原著論文/症例報

Wide field-of-view lensless fluorescence imaging device with hybrid bandpass emission filter

We demonstrate a highly sensitive lensless fluorescence imaging device with a wide field-of-view by using a hybrid bandpass filter composed of interference filters, an absorption filter, and a fiber optic plate. The hybrid filter shows high excitation light rejection characteristics even in a lensless setup. In this study, we fabricated a hybrid bandpass filter and improved fluorescence observation performance for a target with auto-fluorescence. The filter was combined with a large image sensor with an imaging area of 67 mm2. As a demonstration, a brain slice from a green fluorescent protein transgenic mouse was observed and fluorescent cell bodies were detected with the lensless imaging device

Optical and Electric Multifunctional CMOS Image Sensors for On-Chip Biosensing Applications

In this review, the concept, design, performance, and a functional demonstration of multifunctional complementary metal-oxide-semiconductor (CMOS) image sensors dedicated to on-chip biosensing applications are described. We developed a sensor architecture that allows flexible configuration of a sensing pixel array consisting of optical and electric sensing pixels, and designed multifunctional CMOS image sensors that can sense light intensity and electric potential or apply a voltage to an on-chip measurement target. We describe the sensors’ architecture on the basis of the type of electric measurement or imaging functionalities

Thin and Scalable Hybrid Emission Filter via Plasma Etching for Low-Invasive Fluorescence Detection

Hybrid emission filters, comprising an interference filter and an absorption filter, exhibit high excitation light rejection performance and can act as lensless fluorescent devices. However, it has been challenging to produce them in large batches over a large area. In this study, we propose and demonstrate a method for transferring a Si substrate, on which the hybrid filter is deposited, onto an image sensor by attaching it to the sensor and removing the substrate via plasma etching. Through this method, we can transfer uniform filters onto fine micrometer-sized needle devices and millimeter-sized multisensor chips. Optical evaluation reveals that the hybrid filter emits light in the 500 to 560 nm range, close to the emission region of green fluorescent protein (GFP). Furthermore, by observing the fluorescence emission from the microbeads, a spatial resolution of 12.11 μm is calculated. In vitro experiments confirm that the fabricated device is able to discriminate GFP emission patterns from brain slices