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Process Mass Intensity (PMI)

PMI Metric

Process development chemists and engineers in pharmaceutical companies are tasked with identifying efficient routes and processes to new chemical entities that become the active pharmaceutical ingredient in final drug products. The efficiency of any molecular synthesis is a combination of the strategy a chemist uses to assemble the different parts of the molecule (i.e., the route to the final target molecule through a series of isolated intermediates) and the subsequent effort to design and optimize the process (i.e., the combination of solvents, reagents, catalysts, process chemicals, etc. that enable bond-making and breaking).

Process mass intensity was proposed as a means of bench marking green chemistry and engineering performance among member companies from the earliest days of Roundtable existence. The first PMI bench marking exercise was held in 2008 and has been held on a regular basis ever since. PMI has helped the industry to focus attention on the main drivers of process inefficiency, cost, and environment, safety and health impact.

Consequently, there has been a progression in tool development from a simple PMI calculator to a convergent PMI calculator, to one that allows a streamlined life cycle assessment, to others that allow standardized comparisons and the last which provides estimations of PMI based on the phase of drug development.

The contribution to green chemistry and engineering of this continuing initiative, and the latter two tools in particular, should not be underestimated. The ability to benchmark and predict process mass intensity of processes use to make complex organic molecules will enable scientists and engineers in academia and industry to develop better, more cost effective and more sustainable processes.

PMI Calculator

Decreasing the overall quantity of materials used to manufacture a final product is a significant challenge for pharmaceutical companies. Because of the large amount of solvent used in typical manufacturing processes, decreasing materials used saves companies money (less purchased and less energy used in workup and isolation). The Process Mass Intensity (PMI) metric was developed as a way to benchmark and quantify improvements towards greener manufacturing processes. The PMI Calculator enables you to quickly determine the PMI value by accounting for the raw material inputs on the basis of the bulk API output.

Download PMI Calculator

Convergent PMI Calculator

The original PMI calculator was enhanced to accommodate convergent synthesis in this second ACS GCI Pharmaceutical Roundtable PMI calculator. The Convergent PMI Calculator uses the same calculations, but allows multiple branches for single step or convergent synthesis.

Download Convergent PMI Calculator

Related Articles

Presentation

Introducing the Convergent PMI Calculator

2014 presentation explaining the reasoning for creating the Convergent PMI Calculator and its methodology.
Presentation

Pharma and Suppliers: Collaborating on Green Chemistry. Launch of PMI Tool

2011 presentation by Dave Houghes going over the background behind making the PMI calculator, Roundtable PMI benchmarking, and the utility of PMI to the pharma supply chain.
Publication

Using the Right Green Yardstick: Why Process Mass Intensity Is Used in the Pharmaceutical Industry To Drive More Sustainable Processes

Concepcion Jimenez-Gonzalez, Celia S. Ponder, Quirinus B. Broxterman, and Julie B. Manley. Org. Process Res. Dev. 2011, 15, 4, 912–917.