Next-generation biosensor technologies for Alzheimer's disease: Innovations in diagnosis, monitoring, and treatment.

Alzheimer's disease (AD), the most prevalent neurodegenerative disorder, remains a global health crisis due to the lack of early diagnostic tools, dynamic monitoring strategies, and effective therapies. Current diagnostic methods such as cerebrospinal fluid (CSF) analysis and neuroimaging, while accurate, are invasive, expensive, and unsuitable for routine screening, highlighting the pressing need for alternative approaches. This review comprehensively examines the transformative role of next-generation biosensors in revolutionizing AD management. By leveraging breakthroughs in nanotechnology, materials science, and artificial intelligence (AI), modern biosensors enable ultrasensitive, non-invasive detection of AD biomarkers, including amyloid-β (Aβ), Tau proteins, and neurofilament light chain (NfL), across diverse biofluids such as blood, saliva, and tears. We critically evaluate electrochemical, optical, and acoustic biosensing platforms, highlighting their integration into wearable and portable devices for real-time disease monitoring and personalized therapeutic interventions. Emerging trends such as AI-driven analytics, CRISPR-based diagnostics, and closed-loop neuromodulation systems are explored for their potential to decode disease progression and optimize treatment responses. Challenges in clinical translation, including sensor stability, regulatory hurdles, and ethical considerations, are addressed to pave the way for scalable, patient-centric solutions. By synthesizing cutting-edge advancements and interdisciplinary insights, this review charts a roadmap for biosensor technologies to shift AD care from reactive to proactive, ultimately improving quality of life for patients and caregivers.