Limit of Vision by Linda Nagata
Virgil Copeland, Randall Panwar, and Gabrielle Villanti are all brilliant young biotechnologists, working together on an artificial life-form affectionately known as "LOVs," an acronym for Limit Of Vision, because in size LOVs are just at the boundary of what the human eye can easily see.
LOVs contain bioengineered human neurons. They enhance brain function when implanted in test animals. Experimentation on humans is, of course, highly illegal. But it's the nature of brilliant and ambitious young minds to ignore the rules. Believing the LOVs to be perfectly safe, Virgil, Panwar, and Gabrielle experiment on themselves, using implanted LOVs to enhance their own cognitive abilities.
But there is a limit of vision, too, when we try to foresee the consequences of technology--especially of a living, thinking technology that can evolve into new forms in a matter of hours.
When the experiment goes terribly wrong, the consequences are bizarre and unforeseeable. Virgil finds himself on the run, riding the whirlwind of a runaway biotechnology that could lead to the next phase of human evolution.