Patent ID: 8916542

Claim:
A method of inhibiting the growth of a bacterium or killing a bacterium in a subject, comprising contacting the bacterium with a derivatized chitosan and an anti-bacterial agent in an effective combined amount, thereby inhibiting the growth of the bacterium or killing a bacterium, wherein the anti-bacterial agent and the derivatized chitosan are present at a concentrations, or administered at doses, which result in a fractional inhibitory concentration (FIC) of less than or equal to 0.5, wherein the derivatized chitosan comprises a chitosan of the following formula (I): wherein: n is an integer between 20 and 6000; and each R 1 is independently selected for each occurrence from hydrogen, acetyl, wherein at least 25% of R 1 substituents are H, at least 1% of R 1 substituents are acetyl, and at least 2% of R 1 substituents are