A deep dive into polymerase chain reaction technology reveals it's surprisingly near-optimal despite being developed in 1987. The author initially set out to find ways to dramatically speed up PCR—used millions of times weekly for gene cloning and disease diagnosis—but research showed photonic PCR using LED lights or lasers only achieves modest time savings, reducing amplification from one hour to about six minutes.

Three main bottlenecks constrain PCR speed: molecular diffusion, DNA strand length, and temperature ramp rates between cycles. Switching polymerases offers the biggest gains—Phusion completes extension in just 15 seconds per kilobase compared to Taq's one minute. Standard thermocyclers heat at 4.75°C/s and cool at 3.82°C/s, while cheaper models like the Bio-Rad T100 run at only 2.5°C/s.

The author funded $3,500 in microgrants through Astera Institute's Fast Biology Bounties to explore photonic PCR approaches from Sebastian Cocioba and "Utah" Hans. However, the analysis concludes these innovations are unlikely to appear in academic labs soon—existing optimizations like faster polymerases already capture most available time savings.