The Pdcl <sub> 2 </ Sub>, The Hb Sensitized Nm Of Sio <sub> 2 </ Sub> Film Co Sensor

Silicon dioxide thin film prepared by a sol-gel technique, was used as a sensing layer after treatment of solution of palladium chloride and copper chloride,because the reduction of Pd2+ ions by CO gas resulted in change of the layer absorbance.With photocurrent measurement at 510nm wavelength, an obvious photocurrent response was observed for 6 10-1 CO gas in comparison with the blank sample and it can be expected that the present sensing layer can detect the concentration of CO gas below 1.8 X 10~5 based on three times of Signal-to-Noise.The sensing layer could be recovered through copper chloride oxidizing Pd. Interferential experiments showed that no obvious response was found for the organic odor in living surroundings. For the improvement of the performence of CO sensors, It was discussed that 3 ~4 pieces of identical standard film were arrayed.Moreover,the optical CO sensor based on sensing layer of hemoglobin/nano-sized SiO2 particles was explored.The sensing element was prepared by embeding hemoglobin in nano-SiO2 film. Using the optical transducer, the concentration of CO was determined based on the change of the spectrum of Hb. Experiment results showed that the present CO sensor possesses high sensitivity and selectivity, fast response, etc. In this study, the method for purification and storage of Hb was improved, and the concentration of the Hb extract was 0.274g/ml.The working wavelengh of the sensor was 620nm, which was optimized by experiments, and the response of Hb to CO was investigated.Finally.the immobilization of Hb was also dissussed.