Noble Metal Nanomaterials Sensor Array For Bacterial Recognition

The detection and identification of bacteria is of great importance in the fields of clinical medicine,biology,environment and food science,and has been the frontier and hot spot of international research.In recent years,with the continuous advances in the research of noble metal nanomaterials,sensors based on noble metal nanomaterials have been greatly developed for detecting biomolecules such as bacteria.Precious metal nanomaterials including gold nanomaterials and silver nanomaterials,etc.,which have excellent physicochemical properties,can be used to construct fluorescent and colorimetric sensors with sensitive detection and visual identification.Array sensors collect multiple non-selective or semi-selective sensing units to identify a range of target molecules,and have the advantages of reducing the difficulty of screening sensing units,expanding the range of applications,and being suitable for analyzing and identifying a range of biomolecules.Therefore,array sensors have received a lot of attention in recent years.In this paper,a fluorescent sensing array and two colorimetric sensing arrays have been constructed using noble metal nanomaterials and successfully applied to the differentiation and identification of complex samples such as bacteria,providing a reference for the development and application of fluorescent and colorimetric sensor arrays.The main results include:(1)Fluorescence sensing arrays based on gold cluster nanomaterials were constructed;the samples with different concentrations of single bacteria,mixed bacteria,and the same bacteria were analyzed to obtain their "fingerprint",i.e.,characteristic response patterns.Through linear discriminant analysis,the differentiation and identification of 11 kinds of bacteria,10 kinds of bacteria with mixed concentration and 5 kinds of bacteria with the same concentration gradient were realized,and the sensitivity and efficiency of the identification of bacteria and other biological samples were improved.(2)The colorimetric sensing array based on gold sphere nanomaterials was constructed to obtain the characteristic response patterns of bacteria.It also successfully identified 12 species of bacteria,10 species of bacteria with mixed concentrations,and 9 species of the same bacteria with concentration gradients by linear discriminant analysis.In addition,this colorimetric sensing array can be used to achieve visual identification of bacteria detection.(3)The colorimetric sensing array based on triangular silver nanoplates was constructed to obtain the characteristic response patterns of bacteria.And eight species of bacteria were successfully identified by linear discriminant analysis.Meanwhile,the solution response color change can be used for visual detection of bacteria by the naked eye.Thus,a colorimetric sensing array with four sensing units was constructed,and complete identification of the eight bacteria analyzed could be achieved.