Trace Metal Assay in GAS CHROMATOGRAPHY ? Yes,

How often I heard about that " GC could not be applied on trace metal determination/"

But I really do not like the general confusing answer: Be a decent chemist, I prefer the answer is ---- it depends.

Yes, GC procedures for the trace determination of entire metal groups, such as the groups I A, II A, lanthanides, and actinide elements are, simply, still nonexistent.

On the other hand, { or however, or but, (<: I learned to say however, but now)} elements, such as Be, Al, Cr, Co, Rh, Cu, Ni, Pd, and V can be determined individually or in small groups at concentrations which compare favorably with other sensitive methods of metal determination. Here I just need a list of ligand types examined to date and the applicability of these in trace determinations is given in Figure.

Cool, Technology is beautiful.

The effects of dead volume on HPLC @ Glucosamine Sulfate HPLC Analysis

The effects of dead volume on Particle Size(1- 5um) HPLC and the resulting chromatography have been well studied and documented by chemist. The effects of dead volume are critical and significant when using 1-5 um columns as the impact on band broadening greatly increases compared to analytical columns. To optimize the use of narrow bore columns, it is the top priority to reduce the potential dead volume throughout the flow path in the system and the HPLC column.

So, general when dead volume can occur at the HPLC column and instrument, our focus is on the HPLC column end fittings and frits.

Replacing the Active Inlet Valve

The active inlet valve needs to be serviced in cases where the pressure ripple is unstable and the leak test verifies problems with the active inlet valve due to internal leaking. The active inlet valve contains a cartridge that is exchanged.
1. Remove the AIV using a 14 mm wrench.
2. Change the cartridge .
3. Reinstall the AIV.

PS: Properly position the AIV cable when you reinstall the valve.

The Pressure @ HPLC

Here I would like to emphasis the pressure at HPLC system again.

General lots of chemists would say"Ok, the maximum pressure is 400 Bar or something" We do not need to pay attention to that, because when it excess its maximum pressure, the system could automatically turn off." That is Right, But for me, that is not a good and satisfying answer I want to. Yes, now I want to further to discuss the pressure @ HPLC. Yes, the maximum pressure is 400 Bar. However, that is pressure of flow pathway is not the same as the 400 Bar.
When we use H2O/MeOH to wash flow pathway to elute residual analyte or air bubbles, Always CAUTION If pressure is too high, the flow cell may be damaged or broken. When removing air bubbles, set the pump pressure limit to 150 psi (10 atm) or less. Flow cell is easy be damaged or broken when we try to use high flow rate solvents to wash. So Bypass the column, pay attention to the maximum pressure and flow rate, is a Good Lab Practices Standard.

PS: A flow cell rebuilt kit is 400$.