Sol-Gel platforms are made up of tiny transparent dots of inert polymer gels with highly porous architecture. They provide an excellent three dimensional matrix to study bio-molecular interactions or assays with enhanced signal intensity (fluorescence or color) without the loss of integrity compared to traditional 2D platforms.

Aptamers are oligonucleotide or peptide molecules that bind to specific target molecules. Using SELEX methodology Aptamers can be generated against the pollutants (like Bis phenol-A) which can be further used to develop assays for sensing, detection or removal.

Visual detection of polluting molecules provides a simple and straightforward method for their identification. Aptamer-metal nanoparticle conjugates enables this task due to aptamer specificity against pollutants and aggregation induced color change of metal nanoparticles.