Chromatography system for automatically separating different compounds in a sample

Abstract

A chromatography system including a chromatography column connected to receive a sample and separate different compounds in the sample, a flow-through detector that outputs a signal indicating the presence of compounds in the sample leaving the column, a fraction collector that directs fractions of the sample from the column to separate fraction wells, and an electronic controller that receives inputs from the detector and controls the fraction collector. The electronic controller monitors the signal from the detector over time and initiates a cut from one well to another at the fraction collector when the signal over time experiences a shoulder where the slope of the signal over time does not change in sign but does change by more than a predetermined amount.

What is claimed is:  
     
         1 . A chromatography system for automatically separating different compounds in a sample by chromatography, and collecting fractions of said different compounds of said sample in separate fraction wells, said system comprising 
 a chromatography column connected to receive a sample and separate different compounds in said sample,    a detector connected to receive said sample from said column and outputting a signal indicating the presence of compounds in said sample passing through said detector,    a fraction collector connected to receive said sample from said detector for directing fractions of said sample to separate fraction wells, and    an electronic controller receiving inputs from said detector and controlling said fraction collector,    said electronic controller monitoring said signal from said detector over time and initiating a cut from one well to another at said fraction collector when said signal over time experiences a shoulder where the slope of said signal over time does not change in sign but does change by more than a predetermined amount and is negative.    
     
     
         2 . A chromatography system for automatically separating different compounds in a sample by chromatography, and collecting fractions of said different compounds of said sample in separate fraction wells, said system comprising 
 a chromatography column connected to receive a sample and separate different compounds in said sample,    a detector connected to receive said sample from said column and outputting a signal indicating the presence of compounds in said sample passing through said detector,    a fraction collector connected to receive said sample from said detector for directing fractions of said sample to separate fraction wells, and    an electronic controller receiving inputs from said detector and controlling said fraction collector,    said electronic controller monitoring said signal from said detector over time and initiating a cut from one well to another at said fraction collector when said signal over time experiences a shoulder where the slope of said signal over time does not change in sign but does change by more than a predetermined amount, wherein said electronic controller determines to initiate a cut from one well to another when said slope is positive, and the slope at one point in time is less than the slope threshold, and the slope at a later time is greater than X times the slope threshold, where X is greater than one.    
     
     
         3 . The system of  claim 2 , where X is greater than 1.5.  
     
     
         4 . The system of  claim 3  wherein X is between 1.5 and 2.5.  
     
     
         5 . The system of  claim 3  wherein the slope at said later time must be less than a slope disable detection threshold in order for said controller to initiate said cut.  
     
     
         6 . The system of  claim 1  wherein said electronic controller determines to initiate a cut from one well to another at said fraction collector when said slope is negative and the slope is greater than a negative slope threshold.  
     
     
         7 . The system of  claim 6  wherein the slope must be less than a slope detection disable threshold in order for said controller to initiate said cut.  
     
     
         8 . The system of  claim 6  wherein said controller determines if said signal is in a valley by said slope being positive at a set time delay past said cut when said slope is negative.  
     
     
         9 . The system of  claim 8  where said controller causes said fraction collector to move to a new well after said set time delay.  
     
     
         10 . The system of  claim 8  where said controller ends collection after said set time delay.  
     
     
         11 . The system of  claim 8  further comprising a user interactive display and input device that permits said user to select whether to collect in valleys.  
     
     
         12 . The system of  claim 2  further comprising a user interactive display and input device that permits said user to enter said slope threshold.  
     
     
         13 . The system of  claim 6  further comprising a user interactive display and input device that permits said user to enter said slope threshold.  
     
     
         14 . The system of  claim 5  further comprising a user interactive display and input device that permits said user to enter said slope disable detection threshold.  
     
     
         15 . The system of  claim 8  further comprising a user interactive display and input device that permits said user to enter said set time delay.  
     
     
         16 . The system of  claim 9  further comprising a user interactive display and input device that permits said user to enter said set time delay.  
     
     
         17 . The system of  claim 1  or  2  further comprising a user interactive display and input device that permits said user to enter a threshold value for said signal for said controller to initiate and stop collection.  
     
     
         18 . A chromatography system for automatically separating different compounds in a sample by chromatography, and collecting fractions of said different compounds of said sample in separate fraction wells, said system comprising 
 a chromatography column connected to receive a sample and separate different compounds in said sample,    a flow-through detector connected to receive said sample from said column and outputting a signal indicating the presence of compounds in said sample passing through said detector,    a fraction collector connected to receive said sample from said detector for directing fractions of said sample to separate fraction wells, and    an electronic controller receiving inputs from said detector and controlling said fraction collector,    said electronic controller monitoring said signal from said detector over time and initiating a cut from one well to another at said fraction collector when said signal is less than a slope detection disable threshold and said signal over time experiences a specified change in slope condition.    
     
     
         19 . The system of  claim 18  wherein said change in slope condition is a change in a negative slope from one negative slope value that is less than a negative slope threshold to another negative slope value that is greater than said negative slope threshold.  
     
     
         20 . The system of  claim 18  wherein said change in slope condition is a change in a positive slope from one positive slope value that is less than a positive slope threshold to another positive slope value that is greater than said positive slope threshold.  
     
     
         21 . A chromatography system for automatically separating different compounds in a sample by chromatography, and collecting fractions of said different compounds of said sample in separate fraction wells, said system comprising 
 a chromatography column connected to receive a sample and separate different compounds in said sample,    a flow-through detector connected to receive said sample from said column and outputting a signal indicating the presence of compounds in said sample passing through said detector,    a fraction collector connected to receive said sample from said detector for directing fractions of said sample to separate fraction wells, and    an electronic controller receiving inputs from said detector and controlling said fraction collector,    said electronic controller monitoring said signal from said detector over time, said controller identifying valleys in said signal from said detector over time, and    a user interactive display and input device that permits said user to select whether to collect during valleys in said signal over time,    said controller either ending collection after identifying a valley or causing a fraction cut at a set time.    
     
     
         22 . The system of  claim 1  wherein said detector is a UV absorbance detector, and said signal is UV absorbance.  
     
     
         23 . The system of  claim 18  wherein said detector is a UV absorbance detector, and said signal is UV absorbance.  
     
     
         24 . The system of  claim 21  wherein said detector is a UV absorbance detector, and said signal is UV absorbance.  
     
     
         25 . A chromatography system for automatically separating different compounds in a sample by chromatography, and collecting fractions of said different compounds of said sample in separate fraction wells, said system comprising 
 a chromatography column connected to receive a sample and separate different compounds in said sample,    a flow-through detector connected to receive said sample from said column and outputting a signal indicating the presence of compounds in said sample passing through said detector,    a fraction collector connected to receive said sample from said detector for directing fractions of said sample to separate fraction wells,    an electronic controller receiving inputs from said detector and controlling said fraction collector,    said electronic controller monitoring said signal from said detector over time said controller identifying valleys in said signal from said detector over time, and    a user interactive display and input device that permits said user to select whether to operate in a custom mode in which the user determines setpoint conditions for initiating and ending collection or to operate in one of a set of preset collection modes in which the setpoint conditions for initiating and ending collection are preset.