Polymer-Based Device Fabrication and Applications Using Direct Laser Writing Technology.

Polymer materials exhibit unique properties in the fabrication of optical waveguide devices, electromagnetic devices, and bio-devices. Direct laser writing (DLW) technology is widely used for micro-structure fabrication due to its high processing precision, low cost, and no need for mask exposure. This paper reviews the latest research progresses of polymer-based micro/nano-devices fabricated using the DLW technique as well as their applications. In order to realize various device structures and functions, different manufacture parameters of DLW systems are adopted, which are also investigated in this work. The flexible use of the DLW process in various polymer-based microstructures, including optical, electronic, magnetic, and biomedical devices are reviewed together with their applications. In addition, polymer materials which are developed with unique properties for the use of DLW technology are also discussed.

Recent Progress of Imprinted Polymer Photonic Waveguide Devices and Applications.

Polymers are promising materials for fabricating photonic integrated waveguide devices. Versatile functional devices can be manufactured using a simple process, with low cost and potential mass-manufacturing. This paper reviews the recent progress of polymer photonic integrated devices fabricated using the UV imprinting technique. The passive polymer waveguide devices for wavelength filtering, power splitting, and light collecting, and the active polymer waveguide devices based on the thermal-optic tuning effect, are introduced. Then, the electro-optic (EO) modulators, by virtue of the high EO coefficient of polymers, are described. Finally, the photonic biosensors, which are based on low-cost and biocompatible polymer platforms, are presented.

Expression of surfactant protein-A in exhaled breath condensate of patients with chronic obstructive pulmonary disease.

Pulmonary surfactant protein A (SP-A) has been associated with host defense in the lung, and contributes to the pathogenesis of chronic obstructive pulmonary disease (COPD). The present study aimed to determine a non­invasive method of measurement of SP­A, and further examine the expression levels of SP­A in patients with COPD. SP­A was detected in the exhaled breath condensate (EBC) obtained from patients with COPD and from non­COPD subjects. The individuals recruited for the present study comprised 60 subjects with and without COPD, who underwent lobectomy for a solitary peripheral lung nodule. EBC was collected using a condenser, and an enzyme­linked immunosorbent assay (ELISA) was used to measure the levels of SP­A. Tissue samples were obtained during lobectomy through resection of the adjacent lung tissues, located >5 cm from the nodule. Western blot analysis and immunohistochemistry were used to measure SP­A and SP­A­positive type II pneumocytes. The results demonstrated that SP­A was detectable in the EBC of all subjects. The results of the ELISA and western blotting demonstrated that the expression levels of SP­A were significantly decreased in patients with COPD, compared with the non­COPD subjects. The reduction of SP­A­positive type II pneumocytes was associated with the expression levels of SP­A. Decreased expression levels of SP­A in EBC were associated with a higher degree of airway limitation. These results suggested that the measurement of SP­A levels in the EBC may serve as a method for monitoring airway obstruction in patients with COPD. Further investigations are required in order to examine these observations further and to elucidate the underlying mechanisms.