However,some groups make use of laboratory-assembled instruments utilizing
HPLC pumps and splitting the mobile phase with a mechanical split to obtain the desired flow rate [42–45]. Considering the low volumes involved with these miniaturized techniques, attention must be paid to dead volumes related to tube connections (I.D.as low as possible), detection cell and injection valve. Injected sample volumes are in the range 10–50 nL, detector cell must be as small as possible (e.g., UV detection on column is usually used with path-length 50–100 lm and 150–320 lm in nano-LC and CLC, respectively). Fig. 1 shows a scheme for laboratory-assembled nano-LC instrumentation