An AIEgen-porphyrin co-assembly sensor array for fingerprinting glycosaminoglycans

Although sensor arrays are powerful for discriminating glycosaminoglycans, the construction of a sensor array is usually cost and labour inefficient. With the purpose to acquire a high dimensional response data using only a limited number of dyes, the rational assembly of fluorescent dye molecules may provide an alternative approach. We envision that co-assembling different dyes within a supramolecular structure can trigger multiple photophysical processes, which should produce high dimensional optical signals.

A supramolecular AIEgen-porphyrin co-assembly is synthesized by assembling a negatively charged AIEgen (TPE) and meso-tetra(4-carboxyphenyl)porphine (TCPP) on the surface of a cationic polymer saying poly(diallyldimethylammonium chloride) (PDDA). With the co-assembly strategy, the aggregation-induced emission of TPE, the aggregation-caused quenching characteristic of TCPP, and especially, the Förster Resonance Energy Transfer efficiency from TPE to TCPP can be manipulated by a dynamic dye assembly approach. A sensor array is thus readily constructed by varying the loading ratio of TPE and TCPP on the surface of PDDA.

The sensor array is determined to be powerful for pattern recognition of various glycosaminoglycans even in 100% serum media through competitive compaction or removal of the aggregated TPE and TCPP dyes on the PDDA surface. It can be successfully applied for accurate and reliable detecting trace GAG analogues in Hep samples and identifying unknown GAG samples with an accuracy of 96.88%.