It's funny that scientists try to create ion transistors and DNA-based computers. Nature has found other ways to process information, though. Trying to "replicate" electronic circuitry using biologic systems has all the drawbacks of both approaches and little if any of the benefits. Biologic systems are based on chemical diffusion in water solutions, therefore they are slower than electronic systems. However, they are massively parallel, self-organizing, self-repairing, swarm-like, use built-in negative and positive selection, and have a propensity for learning at all structural levels. More importantly, they mix "hardware" and "software" in a way that still escapes human understanding. But then again, why not...