vargis 2 (IMAGE) Utah State University Caption Bruch’s membrane is being modeled on a Transwell, which is made of plastic (row 1) compared to hagfish slime proteins (row 2) which are smooth and nonporous. Hagfish slime proteins are the better option for in vitro models. Credit American Chemical Society Usage Restrictions N/A License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.