L-Lysine increased

Ryser, H.P., Shen, W.C. (1978). Conjugation of methotrexate to poly(L-lysine) increases drug transport and overcomes drug resistance in cultured cells. Proc. Natl. Acad. Sci. U.S.A., 75, 3867-3870. 

As illustrated, increasing the size of poly-L-lysine increased the resistance of the complex to hydrolysis by RNase A. More importantly again, however, was the fact that as the size of the... 

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