To realize fast and sensitive detection of NH3 in the environment

a cross-responsive 6×6 visual sensor array is developed using porphyrin

prophyrin derivatives

and pH indicators that are sensitive to NH3.Using the visual sensor arrays

4 different volume fraction of NH3 are detected

the response time is less than 30 s

and 10-9 volume fraction of NH3 can be effectively identified.The digital data library are analyzed with statistical methods

which suggests that linear relationship exists between the euclidean distance and volume fraction.The correlation coefficient R2=0.996 2.SPSS clustering analysis result shows that the accuracy of identification on different volume fraction is 100 %.NH3 can be fastly and sensitively detected using the visual sensor arrays.