Stuck on a crossword puzzle? Decode this tricky prefix for the answer!

Prefixes, small groups, letters, added, beginning, word, change, meaning, ‘nano’, one-billionth, commonly used, fields, science, technology, very small units, measurement, electronics, nanometer, size, transistors, components, nanosecond, time, duration, electrical signals, medicine, particles, penetrate, individual cells, nanoparticles, potential drug carriers, deliver medications, site, disease, applications, nanotechnology, design, extremely small devices, materials, working, nanoscale, scientists, engineers, create, new technologies, efficient, effective, current ones, sum it up.