文摘
In this work, a new glow discharge, microwave-induced-plasma (GDMIP), tandem ion source was developed,characterized, and used in conjunction with time-of-flightmass spectrometry. This tandem source was designed tobe simple and compact. The GD and the MIP unit areindependent and demountable, providing flexibility intuning and operating. The microwave plasma can beformed with very low power (a few watts) and overlappedwith the glow discharge. The discharge current increasedwith the addition of microwave discharge when the GDwas operated in constant-voltage mode, and the amplitudeof the current increase was found to be related tomicrowave power, discharge pressure, and samplingdistance. With the addition of microwave discharge,significant signal enhancement was achieved under adischarge pressure of 2.0 Torr and a discharge voltage of500 V with 2.0-mm sampling distance. Enhanced factorsof analyte signals ranging from ~1 to nearly 10 could beobtained with MIP boosting, while no significant changein noise level was observed. This new tandem sourceprovides improved performance in direct solid sampleanalysis.