聚二甲基硅氧烷

Background: Heparan sulfate proteoglycans (HSPGs) at the cell surface play an important role in cell adhesion, spreading, formation of focal adhesion complexes (FACs), and sensing mechanical stress. Syndecans are members of the HSPGs family and are highly expressed in various tumor cells. Syndecan-4 (SDC4) is a unique member of syndecans that activates protein kinase C alpha (PKCα). However, syndecan-4 in tumor cells development is not clear when receiving mechanical stress.

Fiber Bragg Grating (FBG) is the most distributed type of fiber-optic sensors. FBGs are primarily sensitive to the effects of temperature and deformation. By employing different transformation techniques, it is possible to use FBG to monitor any physical quantity. To use them as parts of sensor applications, it is essential to encapsulate FBGs to achieve their maximum protection against external effects and damage. Another reason to encapsulate is increasing of sensitivity to the measured quantity.

This article focuses on the functionality verification of a novel non-invasive fibre-optic sensor monitoring basic vital signs such as Respiratory Rate (RR), Heart Rate (HR) and Body Temperature (BT). The integration of three sensors in one unit is a unique solution patented by our research team. The integrated sensor is based on two Fiber Bragg Gratings (FBGs) encapsulated inside an inert polymer (non-reactive to human skin) called PolyDiMethylSiloxane (PDMS).

In this article we report on the validation of a novel fiber-optic sensor system suitable for simultaneous cardiac and respiration activity monitoring during Magnetic Resonance Imaging (MRI) examinations. This MRI-compatible Heart Rate (HR) and Respiration Rate (RR) measurement system is based on the Fiber-optic Bragg Grating (FBG) sensors. Using our system, we performed real measurements on 4 test subjects (2~males and 2 females) after obtaining their written informed consents.

Molecular-level and particle-dispersed inorganic-organic hybrids, containing TiO as the inorganic component, have been prepared in order to study the effect of the introduced inorganic phase dimension on the structure and properties of the hybrids. The hybrids prepared from silanol-terminated polydimethylsiloxane (PDMS) and titanium ethoxide (Ti(OEt)) in the molar ratios of Ti(OEt)/PDMS=1, 2 and 4 were transparent with no visible particles, thus considered as molecular-level hybrids.

The coloration behavior of the inorganic/organic hybrids prepared from polydimethylsiloxane (PDMS) and chemically modified metal alkoxides was investigated by ultraviolet-visible (UV-VIS), X-ray photoelectron (XPS) and electron spin resonance (ESR) spectroscopies. Although the hybrids were transparent in the visible region, a broad absorption was observed from the visible to UV regions, leading to a color from yellow to wine-red. The color and the absorption edge of the hybrids depend on the inorganic components derived from metal alkoxides.

AbstractThe preparation of highly compatible polydimethylsiloxane/epoxy system has been a challenging task. Here, we designed and synthesized a vinyl-containing bifunctional epoxy resin, which was chemically bonded with polydimethylsiloxane by hydrosilylation. A silicone-epoxy block hybrid network with restricted micromorphology and outstanding macro-performance was formed. The phase separation scale of polydimethylsiloxane/epoxy system was strictly restricted by molecular structure design and the modified PDMS was transparent.

We demonstrated that our previously developed gas-phase fluoroalkylsilane patterning method was applicable to polydimethylsiloxane (PDMS) and we compared the stability of patterned proteins and cultured cells between PDMS and glass surfaces. The shapes of the protein patterns were stable on both glass and PDMS surfaces for more than 1 week. The cell patterns were stable on glass surfaces for 1 week, while those on PDMS collapsed within a few days.