Several researchers are working on iPSC to hepatic differentiation. Commonly, the first step required is definitive endoderm differentiation. Following the definitive endoderm fate, the cells need to be taken through posterior foregut fate and then towards hepatic. There is no one culture media to accomplish these different steps available today. Currently this process involves the use of specific media systems at each of the step during the differentiation process.
The following reference may be useful to you, however we have not performed this protocol in our labs and cannot comment on reproducibility.
• Highly Efficient Differentiation of Functional Hepatocytes From Human Induced Pluripotent Stem Cells (PMID: 23681950) - http://stemcellstm.alphamedpress.org/content/2/6/409.full.pdf+html