We demonstrate a low-threshold microsphere laser on a silicon chip, fabricated from erbium-doped silica sol–gel film. Single-longitudinal mode lasing emission is observed from a 37 μm diameter microsphere cavity with an erbium ion concentration of 2× 1019 cm−3. The measured lasing threshold of the silica microsphere laser is as low as 4.8 μW. (Some figures may appear in colour only in the onlin...

The release process of phenol blue from a dibutyrylchitin microsphere, prepared with chitin from a silkworm, into an aqueous solution was kinetically analyzed by single microparticle injection/manipulation and absorption microspectroscopy. The distribution ratio and the release rate of phenol blue in the single microsphere/water system were significantly influenced by the pH of the solution. Th...

In this paper, we have proposed a shell type dielectric microsphere resonator in order to enhance its quality factor. In this work we have assumed that the radius of dielectric microsphere is 12μm and that the interior metal layer radius is 11.5μm. We have obtained analytic equations for Vector potentials, characteristic equation, quality factor, resonance frequency and resonance location of TE...

BACKGROUND Alginate lyases belonging to polysaccharide lyase family-7 (PL-7) are the most well studied on their structures and functions among whole alginate lyases. However, all characterized PL-7 alginate lyases are from prokaryotic bacteria cells. Here we report the first identification of eukaryotic PL-7 alginate lyase from marine red alga Pyropia yezoensis. METHODS The cDNA encoding an a...

Alginate is a polysaccharide produced by certain seaweeds and bacteria that consists of mannuronic acid and guluronic acid residues. Seaweed alginate is used in food and industrial chemical processes, while the biosynthesis of bacterial alginate is associated with pathogenic Pseudomonas aeruginosa. Alginate lyases cleave this polysaccharide into short oligo-uronates and thus have the potential ...

Carbohydrate polymers are industrially and medically important. For instance, a polysaccharide, alginate (from seaweed), is widely used in food, textile and pharmaceutical industries. Certain bacteria also produce alginate through membrane spanning multi-protein complexes. Using Pseudomonas aeruginosa as a model organism, we investigated the biological function of an alginate degrading enzyme, ...

Alginates are classed as a dietary fibre and have been shown to inhibit digestive enzymes in vitro, and therefore could be used as an obesity treatment. The current study aims to assess whether alginate in a bread vehicle maintains its inhibition properties despite cooking and digestion, and may therefore be used as a potential treatment for obesity. After 180 min in a model gut that replicates...

Alginate hydrogels are well-characterized, biologically inert materials that are used in many biomedical applications for the delivery of drugs, proteins, and cells. Unfortunately, canonical covalently crosslinked alginate hydrogels are formed using chemical strategies that can be biologically harmful due to their lack of chemoselectivity. In this work we introduce tetrazine and norbornene grou...

Soft alginate hydrogels support robust neurite outgrowth, but their rapid disintegration in solutions of high ionic strength restricts them from long-term in vivo applications. Aiming to enhance the mechanical stability of soft alginate hydrogels, we investigated how changes in pH and ionic strength during gelation influence the swelling, stiffness, and disintegration of a three-dimensional (3D...

Cell microencapsulation in alginate hydrogel has shown interesting applications in regenerative medicine and the biomedical field through implantation of encapsulated tissue or for bioartificial organ development. Although alginate solution is known to have low antiviral activity, the same property regarding alginate gel has not yet been studied. The aim of this work is to investigate the poten...