A variable flow rate injector provides accurate, precise, and reproducible
injection volumes that have low dispersion. The invention is particularly
well-suited for HPLC injection volumes <500 nL but can be used to
inject larger volumes and in different applications as well. Injections
are performed at a first flow rate and separations are performed at a
second flow rate. For improved IIPLC system performance, the first flow
rate is less than the second flow rate. The injector uses a variable flow
rate fluid supply that allows rapid switching between flow rates desired
for injection and flow rates desired for separations.
