In 2018, Dr Tan was involved in a Initial Coin Offering (ICO) process on a blockchain project he co-founded. Here is the site and whitepaper - http://www.wellderly.network/
The ICO did not go through due to poor investor climate on cryptocurrency projects then. Dr Tan continued to be involved in Blockchain based startups since. Here is an article in Blockchain friendly magazine site "Medium" -https://medium.com/@drtan_18581/blockchain-use-in-eldercare-funding-ecosystem-in-singapore-3c81dfd2b519
Here is Dr Tan speaking in a conference in Monaco in 2018 on Healthcare and Blockchain.