Protein Discrimination using a Fluorescence Based Sensor Array of Thiacarbocyanine-GUMBOS.

Sensitive and selective detection of proteins from complex samples has gained substantial interest within the scientific community. Early and precise detection of key proteins play an important role in potential clinical diagnosis, treatment of different diseases, as well as in proteomic research. In the study reported here, six different compounds belonging to a group of uniform materials based on organic salts (GUMBOS) have been synthesized using three thiacarbocyanine (TC) dyes and employed as fluorescent sensors. Fluorescent properties of micro- and nano- aggregates of these TC-based GUMBOS formed in phosphate buffer solutions are studied in the absence and presence of seven proteins. Fluorescence response patterns of these TC-based GUMBOS were analyzed using linear discriminant analysis (LDA). The constructed LDA model allowed discrimination of these seven proteins at various concentrations with 100% accuracy. The sensing and discrimination abilities of these TC-based GUMBOS were further evaluated in mixtures of two major proteins, i.e. human serum albumin (HSA) and hemoglobin (Hb). Fluorescent response patterns of these mixtures were analyzed using LDA. This model allowed discrimination of various mixtures with 100% of accuracy. Moreover, spiked urine samples were prepared and the responses of these sensors were collected and analyzed using LDA. Remarkably, discrimination of these seven proteins was also achieved with 100% of accuracy.