Bio-Responsive Biosensor-Integrated Drug Delivery Platforms for Precision Cancer Therapy

Abstract

Biosensor-coupled smart drug delivery platforms have evolved into a new frontier in precision medicine, offering various disease surveillance and targeted therapy intervention. These platforms combine the real-time analytical capabilities of biosensors with precisely modulated therapeutic delivery mechanisms, enabling dynamic responses to specific physiological cues. Smart polymers, bio-microelectromechanical systems (MEMS), and bio-electrochemical sensing devices (bioESD) are at the core of these innovations, having been extensively explored in managing chronic conditions notably diabetes mellitus, oncological and cardiovascular pathologies, in addition to advancing tissue engineering and regenerative therapeutics. The operational principle of these systems involves continuous sensing of biologically relevant molecules—such as metabolites, nucleic acids, or proteins—followed by drug release triggered by specific biochemical signals. Their primary advantages include exceptional sensitivity, rapid drug delivery kinetics, and the potential to significantly improve patient compliance and quality of life. In oncology, the tumor microenvironment (TME) offers multiple endogenous triggers that can be exploited for selective drug release. Tumor tissues differ substantially from healthy tissues, exhibiting hypoxia (O₂ depletion), mildly acidic pH, elevated glutathione (GSH) levels, and increased expression of specific enzymes such as hyaluronidase. These unique biochemical features have been strategically harnessed to design bio-responsive drug delivery systems sensitive to pH, redox state, enzymatic activity, or tumor-associated molecular markers (e.g., miRNA, nucleolin). Such stimuli-responsive platforms offer high precision in localizing therapeutic action while minimizing systemic toxicity. One example is glucose oxidase (GOx)-based biosensing, which leverages the abnormally high glucose consumption rate of tumor cells. GOx catalyzes the oxidation of β-D-glucose to gluconic acid and hydrogen peroxide (H₂O₂), consuming molecular oxygen in the process. This reaction not only serves as a diagnostic marker—by detecting oxygen depletion, pH reduction, or H₂O₂ generation—but also acts as a therapeutic trigger. GOx has been combined with hypoxia-activated prodrugs, photosensitizers, or Fenton’s reagents to enable multi-modal cancer therapies, including synergistic oxidative stress induction and photodynamic effects. Recent research has demonstrated that biosensor-integrated drug delivery platforms can achieve adaptive, feedback-controlled cancer therapy, wherein drug release is continuously modulated based on tumor-specific biochemical changes. Such approaches are advancing toward intelligent nanomedicine paradigms, in which a single theranostic platform can diagnose, monitor, and treat cancer in real time.