Embodiments of the present invention are directed to methods and articles of manufacture to treat skin to improve and/or increase hydration, pliability, and thickness for improved texture, feel and appearance. Embodiments feature applying an effective amount of an acetylation agent to natural dermal collagen under reaction conditions to react the natural dermal collagen with the acetylation agent to form a modified collagen. The modified collagen has a higher net charge and higher net charge density than natural dermal collagen. The modified collagen improves or increases one or more skin characteristics consisting of hydration, pliability and thickness.