Aptamer-based Stimuli-Responsive Surfaces

Abstract

This book chapter provides an overview of aptamer-based stimuli-responsive surfaces, which are functional materials that exhibit dynamic changes in their surface properties in response to specific external stimuli by employing aptamers, the engineered oligonucleotides which can specifically bind to their target molecules, as the essential sensing unit. Earlier research focused on stimuli-responsive surfaces made from DNA and proteins, which paved the path for the implementation of aptamer-based stimuli-responsive surfaces. The stimuli-responsive systems harness various stimuli to trigger desired responses, such as metal ions, small molecules, enzymes, pH value, temperature, electrical fields, and light exposure. In the field of molecular sensing and targeting, electrostatic stimuli are scalable and easily reversible but lack specificity. In contrast, aptamer-target interactions present remarkable specificity at nanoscale. Hence, the performance of smart surfaces with combination of aptamer and electrostatic stimuli could be optimized. In the field of cellular targeting and regulation, conformational transition of either the aptamer structure itself, or its conjugated structure in the biointerface in response to various types of stimuli serve as the essential mechanism to govern or modulate the performance of the smart surfaces. Overall, this book chapter covers the design and synthesis of aptamer-based stimuli surfaces, and their broad applications in biosensing, drug delivery, cell capture and release, and other potential fields; prospective challenges and future directions are also briefly discussed.