PAT is driving the need for in situ process monitoring capabilities. Most early stage process development is done is done in simple disposable reactors that lack any monitoring and control capabilities. In part, this is due to the lack of available sensor technology. We have focused on developing low-cost non-invasive optical sensors that promise to address this need. We will describe these next generation sensors to monitor pH, dissolved oxygen, dissolved CO2 using non-invasive optical sensors. In addition, promising new high throughput glucose and glutamine sensing schemes are being developed. These can be readily implemented in a variety of different reactor configurations and scales. These tools promise to pave the way for next generation bioreactors that offer a scalable paradigm to help the implementation of PAT at all the stages of a bioprocess.