Sensing for Biomedical Application

Fabrication and Biomedical Application of Core-Shell Nanoparticles [ 下載 PDF ]

Fang-hsin Lin, Ruey-an Doong

Core-shell particles are novel nanomaterials which can be fabricated using two or more different materials to form core and shell layers. Compared to the single nanoparticles, nanocomposite coreshell particles have many advantages such as wide applicability, good tunability and high sensitivity when compared to the single nanoparticles. Nanocomposite core-shell particles have been extensively utilized in the areas of nanosensing, immunoassay, molecular imaging and therapy. By changing core and shell materials, several physical and chemical properties including magnetic, electronic, catalytic and optical properties can be easily controlled. CdSe/ZnS quantum dots and SiO₂/Au metal nanoshell are the most often used nanocomposite core-shell particles for biomedical applications to the fields of nanosensing, immunoassay, drug delivery and molecular imaging. In this text, the fabrication and application of core-shell nanoparticles are introduced. In addition, the future development of core-shell particles as nanosensors will be presented and discussed.

Micro/Nano Biosensing System and Its Application on Biomedicine [ 下載 PDF ]

Ching-Yu Chang, Hsien-Chang Chang

Development of micro/nano biosensors had not only established a fresh platform but also expanded the essential scopes for the biomedical researches which covers science, engineering, medicine and agriculture fields. By these advanced sensing technologies, people can observe the molecules transportation in the cell and the micro interaction between cells, then the prior hypothesizes and theories can be validated with the success of these technologies; on the other hand, these technologies gradually play an important role for the biomedical detection. The biosensor showed a diverse developments and applications with respect to the impact of nano technology. In this article, we briefly described the sensing principle and also some advance and unique characteristics of micro/nano biosensor. The advanced biosensing systems which were developed for the detection of biochemistry, immunological proteins and genomic nucleotides in human blood were taken as examples to compare the developing technologies with current methods; we addressed some possible challenges for the new ones. Finally, we summarized the chances that micro/nano biosensors can play in the molecular diagnosis of human blood, and proposed the future trends and challenges for the new sensing technologies based on the market and practical considerations.

Nanosensor in Biomedicine [ 下載 PDF ]

Jar-Jin Bai, Chun Chin Lin, Chung-Shi Yang

The development of nanotechnology has imposed profound impact on the biomedical detection and diagnosis. The combination of nanoscience, biochemistry and photonics has made it possible to detect and monitor biomarkers at the molecular and even atomic level, and subsequently bring diverse potential application targeting on cellular medicine research and development. The major theme of this article is to overview the fundamental principles of biomedical sensing, including the surface modification of nanoparticles, nano-material development, and the detection mechanisms.

Biosensors Based on Noble Metal Nanoparticles [ 下載 PDF ]

Wei-Ting Hsu, Lai-Kwan Chau

Noble metal nanoparticles exhibit a characteristic absorption band in the absorption spectrum, known as 'localized surface plasmon resonance (LSPR)'. The absorbance and peak wavelength of the LSPR band are linearly dependent on the refractive index of the surrounding medium. The sensing sensitivity can be increased by using nanoparticles of different shapes and by using waveguides to increase the optical path. The nanoparticles can also be functionalized to allow the selectivity of the sensor. Since the detection process is based on the change of refractive index of the surrounding medium when the analyte interacts with the molecular recognition group on the nanoparticle surface, the analyte does not require to have a spectroscopic signature (e.g. fluorophore, chromophore, etc.). Thus, noble metal nanoparticles can be used to construct label-free sensors.

Principles and New Developed Techniques of Portable Devices for Determining Blood Coagulation Time [ 下載 PDF ]

Chia-Chern Chen, Tsun-Mei Lin, Hsien-Chang Chang

The need of an ideal point-of-care (POC) blood coagulation analyzer increases rapidly due to the increased invasive medical procedures and the prescription of both antiplatelet agents and anticoagulants. A POC coagulation analyzer features its portability, easy to use, providing rapid results, multifunction, safe and low equipment and operating costs. This article provides the basic principles and knowledge for designing an ideal portable blood coagulation analyzer and the future view on the techniques and markets of it.

Biomedical Application of Magnetic Nanoparticles: Principles and Current Developments [ 下載 PDF ]

Kun-Feng Lee, Chao-Hung Kao, Cheng-Yi Chen, Chi-Min Chau, Hui-Ju Cho, Yuh-Jiuan Lin

Magnetic nanoparticles have been utilized for biomedical purpose due to their unique features such as its superparamagnetism, high saturation magnetization and high effective surface areas, etc. In diagnosis aspect, magnetic nanoparticles can be used as contrast agents for magnetic resonance imaging, and as labels for biomedical sensing. On the other hand, they have attracted attention in disease therapies because of their potential as carriers for site-specific drug delivery and heating mediators for hyperthermia. However, the bio-separation is also an important in vitro application of magnetic nanoparticles. In this article, the development of variety of biomedical application including biomedical diagnosis imaging, disease therapies, bio-separation and biosensing were introduced.

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The Principle and Applications of Gas Chromatograph Isotopic Ratio Mass Spectrometer [ 下載 PDF ]

Yong-Chien Ling, Ming-Sheng Hsu, Jenn-Ru Shao, Yu-Sheng Yin, Chia-Yi Yang

The organic compounds in nature are usually consisted of basic units such as atoms and molecules. The isotope ratio of the composing atom are generally affected by factors including the environment of raw materials (namely, reactants), the reaction pathway (such as manufacturing means, synthetic means, and growth means), weathering sample collection, storage, preparation, treatment, analysis, etc. The resultant ratio is different and varying. Gas chromatograph – isotope ratio mass spectrometer (GC-IRMS) uses GC to separate sample into individual organic compound which is combusted under high temperature (800–950 °C) in furnace and form CO₂ and H₂O. After the removal of H₂O, the products enter the IRMS. Three ions with m/z = 44 (¹²C¹⁶O₂), 45 (¹³C¹⁶O₂), 46 (¹²C¹⁶O¹⁸O) are detected. The paper first introduces the origin of isotope difference among organic compounds. The instrumental principles and kinds of commercially available GC-IRMS are briefed thereafter. Based on the content of 5 review papers, the applications of GC-IRMS in food science, illicit drugs, environment science, and biodegradation fields are discussed.

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The Implementation of Arcing-Based and GRINBased Fiber Lens [ 下載 PDF ]

Chun-Jen Weng, Jerwei Hsieh, Chih-Hsien Yao

This article reports on analysis and fabrication of arcing-based and GRIN-based fiber lens. The comparisons with their performance and limitation have also been conducted in this work. Using arc-discharge fusion at end of coreless fiber spliced to SM fiber can produce an arcing-based fiber lens whose radius of curvature can be controlled from 70 µm to 125 µm with ±1.5 µm error. The GRIN-based fiber lens are composed of two welded section: GRIN fiber and coreless silica fiber spliced to SM fiber. The length of GRIN fiber can be cleaved from 100 µm to 10 mm with ±10 µm error. The tilt angle of optic axis due to off-axis misalignment of arcing-based fiber lens is about 4.9° while the tilt angle of optic axis of GRIN-based fiber lens is only 0.5°.