We have studied the possibility of creating a superhydrophobic surface based on the unique micro-structure of polypropylene material.
As a result, it was confirmed that a contact angle of 150 degree or more could be realized by optimizing the dimensions of height, pitch and tip radius of the grooves.
Additionally, we have tried to improve the resistance against friction force which is one of the big issues associated with this technology and have demonstrated that this is essentially influenced by the tip radius of the grooves.
Consequently, the micro-grooves, of which the tip radius is about 5.0 μm, showed both high hydrophobicity (130 degree) and friction resistance. It is anticipated that superhydrophobic surfaces will be utilised in future for home appliance products.
Gold nanoparticle (NP)-loaded semiconductors (Au/SCs) have emerged as a new type of visible-light photocatalysts. The so-called “plasmonic photocatalyst” has strong and broad visible-light absorption by the localized surface plasmon resonance well matching the solar spectrum. A key parameter for the photocatalytic activity is the Au particle size. This review paper deals with the Au particle size effect on various solarto-chemical transformations.
Early diagnosis of cancer is important for the success of clinical treatments. Blood testing is a useful method for detecting cancer by measuring biomarkers, which are proteins produced by cancer cells. Enzyme Linked Immunosorbent Assay is often used to quantitatively analyze proteins. Although blood testing is simple and minimally invasive, the specificity of existing biomarkers is not sufficient for definitive cancer diagnosis. Surface Plasmon field-enhanced Fluorescence Spectroscopy (SPFS) is well known as one of the most sensitive technologies for fluorescence detection. By localizing excitation energy and optimizing the design of the sensor, SPFS performs much higher signal-to-noise ratio than conventional methods. We developed an automated immunoassay system with SPFS technology and evaluated its performance using Prostate Specific Antigen (PSA) assay, which is commonly used as a model marker in prostate cancer diagnosis. The effective sensitivity of the automated immunoassay system was under 0.04 ng/mL, and the analytical sensitivity was 0.00032 ng/mL. The dynamic range was 0.00032-10 ng/mL. We believe that a highly sensitive SPFS immunoassay system can provide greater value than previous systems by detecting new biomarkers.
Anisotropic gold nanocrystals, such as nanowires and nanoflowers, are attractive because of their potentials for novel optical and catalytic properties. In this review, we described optical property of anisotropic gold nanowires and nanoflowers prepared by using capping agent with amine group, which has selective adsorption property on gold surface. Dispersion and morphological stabilities of gold nanoflowers were improved by supporting Al2O3 and coating SiO2, respectively, and the localized surface plasmon resonance was changed by supporting and coating method. In addition, the supported gold nanoflowers showed high catalytic activity for alcohol oxidation.
The substrate with a wavelength-size periodic structure (grating structure) coated with thin metal layers is called a plasmonic chip. It can provide the enhanced fluorescence excited by the grating-coupled surface plasmon resonance (GC-SPR) field. In this paper, the structure pattern for the enhanced fluorescence is introduced and the plasmonic chip is applied to the fluorescence microscopic imaging and the sensitive immunosensor based on the fluorescence detection. The improvement of the fluorescence enhancement and the detection sensitivity are discussed and the advantage of a plasmonic chip is explained.