Introducing the MSQ
_______________________________________________ The Source–An Introduction to API Techniques
Spectral Characteristics
Like electrospray, APCI is a soft ionization technique and forms singly
charged ions–either the protonated, [M+H]
+
, or deprotonated, [M-H]
-
,
molecule–depending on the selected ionization mode. Unlike electrospray,
however, APCI does not produce multiply charged ions and so is unsuitable
for the analysis of high molecular weight compounds such as proteins or
peptides.
Although a high temperature is applied to the probe, most of the heat is used
in evaporating the solvent, so the thermal effect on the sample is minimal. In
certain circumstances (for example, with very thermally labile (unstable)
compounds), the heated probe may cause some thermal fragmentation.
Flow Rate
Flow rates of 0.2 to 2.0 mL/min can be used with APCI.
___________________________MSQ Hardware Manual ___________________________
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