Biosensors Move Cancer Detection Toward the Point of Care, Review Finds

A sweeping review published in Discover Sensors argues that biosensor technologies are closing a persistent gap in cancer care: the need for rapid, sensitive, low-cost detection of tumor biomarkers outside centralized laboratories. The review, authored by Shruti Patil, Hemant Kumar Tatapudi, Kishore Raju Vatsavai, Pavan Kumar Jaini and Kiran Kumar Chagarlamudi and published on 29 August 2026, synthesizes recent work on electrochemical, optical, mass-sensitive, microfluidic, nanomaterial-based and hydrogel biosensing platforms for cancer diagnosis and monitoring. It arrives against a stark backdrop: around 20 million cancer cases were diagnosed worldwide in 2022, causing almost 10 million deaths, with projections that this pattern will continue to rise significantly in the years ahead.

The authors frame the clinical problem in terms of the limitations of conventional diagnostics. Imaging, histopathology, ELISA, PCR and other centralized immunoassays have transformed patient management, the review notes, but they carry serious constraints: invasive tissue biopsy, dependence on advanced infrastructure, batch processing, high cost, and time delays that are inconsistent with real-time treatment decisions. Standard laboratory methods can also struggle to detect low-abundance markers of early-stage malignancy or minimal residual disease. Malignancies caught at a localized stage are associated with significantly higher survival than those that have metastasized, which makes the sensitivity gap at early stages a matter of life and death. Biosensors, the review argues, fill these voids by enabling sensitive, specific and rapid identification of circulating cancer biomarkers from minimally invasive liquid biopsies such as blood, serum, plasma, saliva and urine.

At the heart of the review is a taxonomy of biomarker classes that biosensors are being engineered to detect. Circulating protein biomarkers, including tumor-associated antigens such as PSA, CEA, CA-125, CA19-9 and HER2/neu, remain the most studied, but their sensitivity and specificity for early-stage disease in heterogeneous populations are limited. Nucleic acid biomarkers, including genomic DNA alterations, circulating tumor DNA (ctDNA) and non-coding RNAs such as microRNAs, capture the dynamic mutational and epigenetic characteristics of tumors. Cell-based biomarkers, particularly circulating tumor cells (CTCs), have become recognized prognostic indicators in several solid tumors, while extracellular vesicles such as exosomes carry proteins, lipids and nucleic acids from the parent tumor. Metabolite-based markers, including lactate, choline and amino acids, reflect reprogrammed cancer metabolism, and tumor microenvironment parameters such as pH, oxygen tension, reactive oxygen species and matrix metalloproteinases offer direct insight into tumor aggressiveness and treatment response.

Electrochemical biosensors receive the most detailed treatment. These devices, classified into potentiometric, amperometric, voltammetric, impedimetric and conductometric types, detect analytes at nanomolar or picomolar concentrations using protein or nucleic acid recognition elements. Recent emphasis has fallen on nanostructured materials such as gold nanoparticles, graphene and metal-organic frameworks, and on screen-printed disposable formats for low-cost point-of-care testing of multimarker panels. The review cites concrete examples: Li and colleagues built an electrochemical sensor for carcinoembryonic antigen using an antibody immobilized on a reduced graphene oxide–PtAu composite, while Jolly and colleagues developed a dual-mode aptasensor for prostate-specific antigen (PSA) with a detection limit of 10 picograms per milliliter, a linear range from 10 picograms to 10 nanograms per milliliter, and cross-reactivity with structurally comparable molecules of roughly 2 percent.

Optical platforms form the second major pillar. Fluorescence, surface plasmon resonance, surface-enhanced Raman scattering and chemiluminescence or colorimetric formats provide label-based and label-free detection of biomolecular interactions at very low concentrations. The review highlights a fiber-optic sensor by Kaur and colleagues operating at 1550 nanometers, engineered with a silica core, metal cladding and two-dimensional materials, whose figure of merit identified a SiO2–PF–Ag–MoS2 probe structure as the most effective for detecting refractive-index variations linked to blood, cervical, adrenal gland and breast cancers. Ribaut and colleagues developed a plasmonic immunosensor for cytokeratin 17, a lung cancer biomarker, capable of producing a stable surface plasmon resonance signal in gel matrices that mimic tissue. Surface-enhanced Raman approaches, the review notes, have achieved detection limits down to attomolar levels for microRNAs and other biomarkers.

Mass-sensitive and acoustic devices, including quartz crystal microbalances, microcantilevers and surface acoustic wave systems, detect biomarkers through resonance frequency shifts induced by mass loading or surface stress, without fluorescent tags. Zhao and colleagues developed a Rayleigh-mode surface acoustic wave immunosensor on ST-cut quartz for carcinoma antigen 125, an ovarian cancer biomarker, operating at 203.5 megahertz with a broad linear range of 0.01 to 300 milliunits per milliliter and a detection limit of 0.00371 milliunits per milliliter. A separate Love-wave sensor with a molecularly imprinted polymer film, designed to detect volatile organic compounds for colorectal cancer diagnosis, achieved up to four times the sensitivity of non-imprinted polymer sensors. Nanobiosensors, meanwhile, exploit the high surface-area-to-volume ratio of nanomaterials to reach attomolar detection limits for ctDNA, microRNAs and sparse proteins, with examples including polysilicon nanowire field-effect transistor sensors for label-free PSA detection in human serum and microfluidic purification chips combined with silicon nanoribbon detectors that capture biomarkers directly from whole blood.

Microfluidic and lab-on-a-chip systems couple microchannels, valves and chambers with electrochemical or optical transducers to process microliter samples with on-chip enrichment, separation and detection. The review cites the CTC-Chip demonstrated by Stott and colleagues for capturing epithelial cell adhesion molecule-expressing circulating tumor cells, a microfluidic chip using the CD71 transferrin receptor to analyze breast and prostate cancer cells, and a surface-patterned gold substrate functionalized with graphene oxide nanosheets that captured circulating tumor cells from pancreatic, lung and breast cancer blood samples with 73 plus or minus 32.4 percent sensitivity at concentrations of 3 to 5 cells per milliliter. Hydrogel and flexible biosensors, a newer category, use three-dimensional hydrated polymer networks matched to the mechanical properties of tissue, enabling wearable or implantable monitoring of tumor microenvironment parameters such as reactive oxygen species in preclinical studies, including a glutathione-responsive polymer dot hydrogel sensor selective for the CD44 receptor in cancer cell lines.

The review is notably candid about why so few laboratory biosensors reach clinical practice. Despite thousands of published studies, only a small fraction have been translated, because real-world deployment requires steady performance across varied biological conditions, broad-scale verification, regulatory approval, stable manufacturing and financial viability. Key barriers include reproducibility, long-term stability, antifouling performance in complex clinical matrices, matrix effects that can cause accuracy deviations greater than 20 percent at low concentrations, biofouling and biolayer formation, the absence of standardized testing protocols, and the high cost of scale-up. Regulatory validation demands extensive evidence of analytical validity, clinical performance and utility, with manufacturing compliance under ISO 13485 and Good Manufacturing Practices. Most approved cancer-related biosensor platforms are molecular diagnostics aimed at genetic markers rather than straightforward electrochemical or optical devices, and reimbursement limitations further impede adoption even after technical and regulatory success.

Looking forward, the authors identify AI-assisted data analysis, 4M biosensors combining multitarget, multiplex, multimodal and machine-learning capabilities, and integrated diagnostic-therapeutic platforms as the dominant trends of the coming decade. CRISPR-based biosensors using programmable Cas enzymes have achieved femtomolar detection limits with single-base specificity for cancer-related mutations, ctDNA and microRNAs, while digital ELISA and single-molecule array technologies can quantify individual biomolecules in femtoliter compartments, supporting early diagnosis and minimal residual disease detection. AI-augmented systems integrating genomic, proteomic and metabolomic data have reportedly achieved up to 87.5 percent accuracy in therapy recommendations, and the market for AI-biosensor systems is projected to grow to 25.43 billion dollars by 2035. The review concludes that laboratory prototypes have demonstrated nanomolar sensitivity, multiplex detection and reported specificity of 96 to 100 percent in distinguishing cancer patients from non-cancer patients, but that widespread adoption will require large-scale clinical validation against gold-standard biopsies, standardized electrode materials, affordable manufacturing, and solutions to biofouling, sensor instability and matrix interference before wearable, continuously monitoring devices become routine in oncology.

Subject of Research: Biosensor technologies for cancer biomarker detection and diagnosis

Article Title: Recent advances in biosensors for cancer diagnosis and analytical strategies

Article References: Patil, S., Tatapudi, H. K., Vatsavai, K. R., Jaini, P. K., & Chagarlamudi, K. K. (2026). Recent advances in biosensors for cancer diagnosis and analytical strategies. Discover Sensors, 2(1), Article 49. https://doi.org/10.1007/s44397-026-00082-w

Image Credits: AI Generated

DOI: 10.1007/s44397-026-00082-w

Keywords: biosensors, cancer diagnosis, liquid biopsy, electrochemical biosensors, optical biosensors, microfluidics, nanobiosensors, circulating tumor DNA, biomarkers, point-of-care testing, machine learning, regulatory approval