Biosensor-Based Innovations in Therapeutic Drug Monitoring: Bridging Traditional Methods and Precision Medicine

Therapeutic Drug Monitoring (TDM) serves as a crucial component of personalized medicine, allowing healthcare providers to tailor drug dosages according to individual pharmacokinetic and pharmacodynamic profiles, thereby maximizing effectiveness and minimizing adverse effects. This detailed review investigates the essential principles and justifications for TDM, stressing its importance for medications with narrow therapeutic windows, considerable variations among patients, non-linear pharmacokinetics, and intricate drug interactions. It outlines the conventional TDM process from evaluating the patient and collecting samples to analyzing measurements, interpreting results, and continuous enhancement while also showcasing alternative methods that include point-of-care testing, non-invasive sampling methods, and AI-based modeling. A critical analysis of traditional analytical techniques such as LC-MS/MS, HPLC-UV/FLD, GC-MS, immunoassays, and atomic spectroscopy is provided, examining their principles, uses, benefits, and drawbacks. Following this, the article highlights the emerging trend towards the use of biosensors, motivated by the limitations of standard approaches like long turnaround times, invasiveness, and expensive procedures. Recent innovations in biosensors featuring continuous monitoring, non-invasive sampling, detailed PK/PD profiling, multiplexing, AI incorporation, CRISPR related systems, and nanomaterials are explored, demonstrating their capacity to transform TDM through real-time, decentralized, and patient-focused methods. The challenges faced in adopting biosensors, such as issues with stability, scalability, and regulatory obstacles, are discussed, emphasizing the importance of hybrid models that integrate both traditional and cutting-edge technologies. Ultimately, this review argues that the incorporation of biosensors in clinical settings can significantly improve patient outcomes in the age of precision medicine.