Advancing cancer diagnostics through multifaceted optical biosensors supported by nanomaterials and artificial intelligence: A panoramic outlook

Cancer is a major global health challenge, with many deaths due to uncontrolled tumor cells. Traditional cancer diagnosis methods, such as physical examination and imaging, often struggle to detect low levels of cancer symptoms in the early stages of the disease. Low levels of cancer biomarkers in early-stage cancer require alternative solutions, diagnostic accuracy, selectivity, and availability. This review focuses on nanomaterial-enabled optical biosensors that address this need by providing improved accuracy and selectivity. It covers developments from 2010 to 2024, discussing the principles of manufacturing, detection methods, and applications of these biosensors for early cancer detection. Optical biosensors integrated with nanomaterials in surface areas have high specificity, low penetration depth, tunable physicochemical properties, and rich surface functionality compared to conventional diagnostics that do not have early, targeted detection. Additionally, we discuss nanomaterial-enabled optical biosensors, including their working principles, detection mechanisms, and cancer biomarker detection applications. The paper summarizes advances in optical biosensing modules based on principles such as surface plasmon resonance, surface-enhanced Raman spectroscopy, fluorescence, colorimetry, chemiluminescence, luminescence, interference, and absorbance or reflectance. The integration of these biosensors with modern technologies like artificial intelligence, machine learning, bioinformatics, the internet of medical things and microfluidics has led to the development of 5th generation intelligent optical biosensors with point-of-care, lab-on-chip, personalized, and wearable features. In addition, the review discusses the challenges, alternative solutions, and prospects of nanomaterial-enabled intelligent optical biosensors, including their manufacturing, clinical implementation, and regulatory considerations to transform cancer diagnostics.