Abstract The high mortality rate of ovarian cancer is directly related to the lack of an effective screening strategy, as up to 90% of cancers that have not metastasized beyond the ovaries can be treated effectively using current strategies. While the biomarker CA125 has been used with some success for detecting ovarian cancer, additional biomarkers can increase the sensitivity and specificity of an ovarian cancer diagnostic test. Here, a panel of 4 biomarkers, CA125, HE4, CA72-4 and MMP-7, has been multiplexed with the programmable Bio-Nano-Chip (p-BNC). A rapid, precise and multiplexable diagnostic system will more successfully validate these suspected biomarkers over traditional methods by utilizing less volume of precious clinical samples and significantly reducing assay times. Additionally, the p-BNC has potential to provide a method for the point-of-care analysis of patients’ health, reducing costs and turn-around times for results. This system utilizes antibodies on nano-nets of agarose microbeads to capture protein biomarkers for a fluorescence-based sandwich immunoassay. By housing the microbeads in individual addressable wells that allow for the sample and reagents to pass through the porous agarose, multiple biomarkers can be analyzed in a single assay. The in-development disposable microfluidic card is utilized to control sample and reagent processing and allows the fluid to interact with the beads, as well as contains all biowaste for safer disposal. Low limits of detection (LODs) and high precision have been achieved using the p-BNC with a short analysis time under an hour, confirming its ability to be used for measuring biomarker levels in the physiological rage. Dose response curves of the four individual biomarkers are performed on the p-BNC system and are compared to the multiplexed dose response curve to ensure minimal cross-reactivity between biomarker reagents. Additionally, all four biomarker assays are compared to EIA using late-stage clinical samples to validate the system's diagnostic value. Concurrently, samples from patients separated into blood, plasma and serum are being used to determine the feasibility of a finger-stick assay for the ovarian cancer biomarkers. A novel card for the p-BNC is now in development for analyzing finger-stick quantities of blood and is being demonstrated to work effectively with high concentrations as a proof of concept. The p-BNC shows strong promise to be an effective system capable of the multiplexed analysis of ovarian cancer biomarkers and now a retrospective trial in collaboration with MD Anderson and UKCTOCS is underway to create a risk of ovarian malignancy algorithm by utilizing pre-clinical sera from 50 patients destined to develop ovarian cancer. Citation Format: Basil Shadfan, Archana Raamanathan, Glennon Simmons, Robert C. Bast, John T. McDevitt. Multiplexed detection of early-stage ovarian cancer biomarkers using a microfluidic bead-based immunosensor. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3495. doi:10.1158/1538-7445.AM2013-3495