GoldenTime: A Blockchain-Based Decentralized Medical Identity And Emergency Response System

Abstract

Healthcare data management faces significant challenges including fragmented records, risk of unauthorized modification, and critical delays during medical emergencies. GoldenTime is a blockchain-integrated medical record management system built on the MERN stack and Ethereum smart contracts that addresses these challenges. The system introduces a dual-tier data model where non-confidential emergency data such as blood group and allergies are publicly accessible via a QR-based Emergency Grid, while confidential records are exposed only through contract functions restricted to on-chain authorized doctors. A Solidity smart contract named GoldenTimeLedgerV3 serves as the immutable data layer, enforcing role-based access through the onlyAuthorized modifier. The backend is implemented using Node.js and Express.js with MongoDB for off-chain mirroring, Cloudinary for file storage, and Nodemailer for OTP-based two-factor authentication. The frontend is built with React 19 and Ethers.js v6 for direct blockchain interaction. The system was deployed and tested on the Ethereum Sepolia test network. Results demonstrate tamper-proof record storage, instant emergency data retrieval without authentication, and a complete doctor credential verification workflow.