Patent ID: 7601543
Filing Date: 2009-10-13
Classification: G01N,Y10T

Abstract:
1. A method of modulating a second carrier in two-dimensional liquid or gas chromatography, wherein a first carrier containing an analyte is separated in a primary column and then partially modulated by introduction of a second carrier before being separated in a secondary column, said second carrier modulated between a primary flow rate and a secondary flow rate, said primary flow rate and said secondary flow rate being unequal, comprising: introducing said second carrier to a modulator; passing said second carrier through a T-connector, wherein said second carrier is at least partially divided into a primary second carrier and a secondary second carrier; said primary second carrier entering a primary pathway connected to a primary exit of said T-connector; said secondary second carrier entering a secondary pathway connected to a secondary exit of said T-connector; regulating said primary flow rate of said primary second carrier with a primary regulator along said primary pathway; regulating said secondary flow rate of said secondary second carrier with a secondary regulator along said secondary pathway; regulating said primary flow rate and said secondary flow rate such that said primary flow rate is slower than said secondary flow rate; monitoring said primary flow rate and said secondary flow rate; regularly alternating a modulating valve, located downstream of said primary regulator and said secondary regulator, between said primary flow rate and said secondary flow rate; venting said primary second carrier when said modulating valve directs said secondary second carrier to a modulator exit downstream of said modulating valve; and venting said secondary second carrier when said modulating valve directs said primary second carrier to said modulator exit.