Quality control method

Abstract

A method of quality control to diagnose the cause of a malfunction of an instrument. The method uses measurements of the physical property of a sample to diagnose the cause of a malfunction of an instrument. The spatial position of a control product sample is analyzed. Alternatively, the spatial position of a statistically significant number of patient blood samples can be used. The method enables the monitoring of an instrument for problems associated with debris and noise caused by red cell lysis inefficiency; instrument reagents pump volume settings; instrument laser alignments; instrument gain settings; and flow noise caused by partial plugs, residual plugs or other flow problems. The method provides a more specific indication of the type and cause of an instrument malfunctioning than non specific flagging provided by prior art methods.

1 - 39 . (canceled)  
     
     
         40 . A method of making a white blood cell analog resistant to degradation by the lytic reagents used in a hematological test instrument, comprising the steps of: 
 (a) providing a composition comprising white blood cells and red blood cells;    (b) treating the composition resulting from step (a) with a lytic reagent to lyse the red blood cells from the white cells;    (c) collecting the white blood cells resulting from step (b);    (d) fixing the white blood cells collected in step (c);    (e) washing the fixed white blood cells; and,    (f) admixing the product of step (e) in a suspension medium suitable for delivering said product to a hematology analyzer for analysis.    
     
     
         41 . A method of making a nucleated blood cell analog resistant to degradation by the lytic reagents used in a hematological test instrument, comprising the steps of: 
 (a) providing a quantity of avian nucleated red blood cells;    (b) treating said nucleated red blood cells with a lytic reagent;    (c) collecting the blood cells resulting from step (b);    (d) fixing the blood cells collected in step (c);    (e) washing the fixed blood cells; and,    (f) admixing the product of step (e) in a suspension medium suitable for delivering said product to a hematology analyzer for analysis.    
     
     
         42 . A method of making a nucleated blood cell analog resistant to degradation by the lytic reagents used in a hematological test instrument, comprising the steps of: 
 (a) providing a quantity of mammalian nucleated red blood cells;    (b) treating said nucleated red blood cells with a lytic reagent;    (c) collecting the blood cells resulting from step (b);    (d) fixing the blood cells collected in step (c);    (e) washing the fixed blood cells; and,    (f) admixing the product of step (e) in a suspension medium suitable for delivering said product to a hematology analyzer for analysis.    
     
     
         43 . A method of using a hematology control product including at least one nucleated blood cell analog resistant to degradation by the lytic reagents used in a hematological test instrument, comprising the steps of: 
 (a) providing a hematology control product including a nucleated blood cell analog, wherein the analog is a blood cell that has been treated with a lytic reagent and a fixative;    (b) providing an instrument for analyzing a blood cell sample by light scatter;    (c) passing the control product through the instrument for detection of said nucleated blood cell analog; and    (d) reporting said nucleated blood cell analog in the control product.    
     
     
         44 . A method according to  claim 43 , said instrument having the capability to analyze a blood cell sample by light scatter at various angular ranges.  
     
     
         45 . A method according to  claim 44 , said instrument having the capability to analyze a blood cell sample by at least one of low angle light scatter, median angle light scatter, and high angle light scatter.  
     
     
         46 . A method of using a hematology control product including at least one white blood cell analog resistant to degradation by the lytic reagents used in a hematological test instrument, comprising the steps of: 
 (a) providing a hematology control product including a white blood cell analog, wherein the analog is a blood cell that has been treated with a lytic reagent and a fixative;    (b) providing an instrument for analyzing a blood cell sample by light scatter;    (c) passing the control product through the instrument for detection of said nucleated blood cell analog; and    (d) reporting said nucleated blood cell analog in the control product.    
     
     
         47 . A method according to  claim 46 , said instrument having the capability to analyze a blood cell sample by light scatter at various angular ranges.  
     
     
         48 . A method according to  claim 47 , said instrument having the capability to analyze a blood cell sample by at least one of low angle light scatter, median angle light scatter, and high angle light scatter.  
     
     
         49 . A white blood cell analog resistant to degradation by the lytic reagents used in a hematological test instrument, said analog produced by 
 (a) providing a composition comprising white blood cells and red blood cells;    (b) treating the composition resulting from step (a) with a lytic reagent to lyse the red blood cells from the white cells;    (c) collecting the white blood cells resulting from step (b);    (d) fixing the white blood cells collected in step (c);    (e) washing the fixed white blood cells; and,    (f) admixing the product of step (e) in a suspension medium suitable for delivering said product to a hematology analyzer for analysis, said analog having the light scatter characteristics of a white blood cell of interest.    
     
     
         50 . A nucleated blood cell analog resistant to degradation by the lytic reagents used in a hematological test instrument, said analog produced by: 
 (a) providing a quantity of avian nucleated red blood cells;    (b) treating said nucleated red blood cells with a lytic reagent;    (c) collecting the blood cells resulting from step (b);    (d) fixing the blood cells collected in step (c);    (e) washing the fixed blood cells; and,    (f) admixing the product of step (e) in a suspension medium suitable for delivering said product to a hematology analyzer for analysis said analog having the light scatter characteristics of a nucleated blood cell of interest.    
     
     
         51 . A nucleated blood cell analog resistant to degradation by the lytic reagents used in a hematological test instrument, said analog produced by: 
 (a) providing a quantity of mammalian nucleated red blood cells;    (b) treating said nucleated red blood cells with a lytic reagent;    (c) collecting the blood cells resulting from step (b);    (d) fixing the blood cells collected in step (c);    (e) washing the fixed blood cells; and,    (f) admixing the product of step (e) in a suspension medium suitable for delivering said product to a hematology analyzer for analysis said analog having the light scatter characteristics of a nucleated blood cell of interest.    
     
     
         52 . A nucleated blood cell analog resistant to degradation by the lytic reagents used in a hematological test instrument, said analog produced by: 
 (a) providing a quantity of nucleated blood cells selected from avian, mammalian, and reptile nucleated blood cells;    (b) treating said nucleated red blood cells with a lytic reagent;    (c) collecting the blood cells resulting from step (b);    (d) fixing the blood cells collected in step (c);    (e) washing the fixed blood cells; and,    (f) admixing the product of step (e) in a suspension medium suitable for delivering said product to a hematology analyzer for analysis said analog having the light scatter characteristics of a nucleated blood cell of interest.    
     
     
         53 . A method of making a control including a nucleated blood cell analog resistant to degradation by the lytic reagents used in a hematological test instrument, comprising the steps of: 
 (a) providing a quantity of nucleated red blood cells selected from avian, mammalian, and reptile nucleated red blood cells;    (b) treating said nucleated red blood cells with a lytic reagent;    (c) collecting the blood cells resulting from step (b);    (d) fixing the blood cells collected in step (c);    (e) washing the fixed blood cells; and,    (f) admixing the product of step (e) in a suspension medium suitable for delivering said product to a hematology analyzer for analysis.