||Sanjiv Kumar et al., Effect of concentration of molecular crowder on the unfolding force distribution: emergence of a long tail, Journal of Statistical Mechanics: Theory and Experiment, Volume 2017, March 2017, link p.3 top paragraph
||Abstract: "[Researchers] investigate the force induced unfolding transitions of a polymer in presence of crowding particles over a wide range of conditions."
||P.3 top paragraph: "Single molecule force spectroscopy (SMFS) techniques have provided important information about molecular interactions and their role in determining the structure of biomolecules and cellular processes [refs 1–4] inside the cell. It is still unclear that whether data obtained from these experiments are capable of predicting the stability of biomolecules inside the living cells or not. Because the interior of cells has a crowded environment, quite different from the environment seen in vitro. In fact, it is occupied by different kinds of biomolecules such as sugar, nucleic acids, lipids, etc. A major faction (≈40%) of the cellular volume is physically occupied and unavailable to other molecules and thus causing obstruction to the free motion of biomolecules inside the cell [primary sources]. However, most of these studies [refs 10–13] have been performed using single molecule in a dilute solution."