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The effect of chemical modification of hyaluronic acid (HA) on its distribution throughout the body was successfully visualized in nude mice through real-time bioimaging using quantum dots (QDots). Adipic acid dihydrazide modified HA (HA-ADH) was synthesized and conjugated with QDots having carboxyl terminal ligands activated with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide and N-hydroxysulfosuccinimide. The formation of HA-QDot conjugates could be confirmed by gel permeation chromatography, fluorometry, transmission electron microscopy, and ζ-size analysis. According to the real-time bioimaging of HA-QDot conjugates after subcutaneous injection to nude mice, the fluorescence of HA-QDot conjugates with a near infrared wavelength of 800 nm could be detected up to 2 months, whereas that with an emission wavelength of 655 nm disappeared almost completely within 5 days. The results can be ascribed to the fact that near-infrared light has a high penetration depth of about 5–6 cm in the body compared to that of about 7–10 mm for visible light. Thereby, using QDots with a near-infrared emission wavelength of 800 nm, the distribution of HA-QDot conjugates throughout the body was bioimaged in real-time after their tail-vein injection into nude mice. HA-QDot conjugates with 35 mol% ADH content maintaining enough binding sites for HA receptors were mainly accumulated in the liver, while those with 68 mol% ADH content losing much of HA characteristics were evenly distributed to the tissues in the body. The results are well matched with the fact that HA receptors are abundantly present in the liver with a high specificity to HA molecules. © 2008 Wiley Periodicals, Inc. Biopolymers 89: 1144–1153, 2008. This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com

Technology has had a profound effect on how services are designed and delivered. There have been many changes emerging in services as a result of technology. This paper describes and provides illustrations of a framework which is useful for technology management in the service sector. The framework focuses on managing according to where the value is added in the service: in the service production system/process (knowledge-embedded) or in the worker him/herself (knowledge-based). This paper explores the strategic technology management issues on different types of service. Copyright © 2006 John Wiley & Sons, Ltd.

Technology as a source of building competitive advantage is playing an important role in many service firms. However, technology management in the service sector has significantly lagged behind that in the manufacturing sector. Service technologies have radically altered the strategic environment in ways that offer significant new opportunities and threats for service firms. In addition, service technologies offer a variety of ways for service providers to add value within their own operations. This paper presents a technology-centred strategic planning model, which emphasizes the important role of technology in strategy formulation and implementation in services. Copyright © 2005 John Wiley & Sons, Ltd.