Single spin process for blood plasma separation and plasma composition including preservative

Abstract

A screening method for the identification of a characteristic of a target nucleic acid in a whole blood sample, including positioning a composition comprising whole blood and at least one preservative agent within a centrifuge, centrifugating the composition to isolate a plasma that includes at least one target nucleic acid for further analysis and analyzing the at least one target nucleic acid to identify a characteristic about the at least one target nucleic acid, and a composition including the plasma, the preservative agent, and any other ingredient, which is produced by the method.

1 : A screening method for the identification of a characteristic of a target nucleic acid in a whole blood sample, comprising the steps of:
 a. positioning a composition comprising whole blood (bio sample?) and at least one preservative agent within a centrifuge;   b. centrifugating the composition at a speed of least about 1000 g for at least about 5 minutes to isolate a plasma that includes at least one target nucleic acid for further analysis;   c. analyzing the at least one target nucleic acid to identify a characteristic about the at least one target nucleic acid,   wherein the centrifugating step is performed at a speed that does not exceed 7500 g for more than 1 minute.   
     
     
         2 : The method of  claim 1 , wherein the preservative agent is selected from the group consisting of: diazolidinyl urea, imidazolidinyl urea, dimethoylol-5,5dimethylhydantoin, dimethylol urea, 2-bromo-2.-nitropropane-1,3-diol, oxazolidines, sodium hydroxymethyl glycinate, 5-hydroxymethoxymethyl-1-1aza-3,7-dioxabicyclo [3.3.0]octane, 5-hydroxymethyl-1-1aza-3,7dioxabicyclo[3.3.0]octane, 5-hydroxypoly[methyleneoxy]methyl-1-1aza-3, 7dioxabicyclo[3.3.0]octane, quaternary adamantine and any combination thereof. 
     
     
         3 : The method of  claim 2 , wherein the concentration of the preservative agent prior to the centrifugating step is between about 1% and about 30% 
     
     
         4 : The method of  claim 1 , wherein the concentration of the preservative agent prior to the centrifugating step is between about 4% and about 10%. 
     
     
         5 : The method of  claim 1 , wherein the concentration of the preservative agent prior to the centrifugating step is a concentration at which cross-linking of nucleic acids and proteins is observed, as indicated by agarose gel electrophoresis. 
     
     
         6 : The method of  claim 2 , wherein the concentration of the preservative agent is less than about 2% of the blood sample. 
     
     
         7 : The method of  claim 1 , wherein the composition further includes one or more other nonaqueous ingredients selected from the group consisting of glycine, lysine, ethylene diamine, arginine, urea, adinine, guanine, cytosine, thymine, spermidine, ethylenediaminetetraacetic acid (EDTA), aurintricarboxylic acid (ATA), glyceraldehyde, sodium fluoride or combinations thereof. 
     
     
         8 : The method of  claim 7 , wherein the ratio (by volume) of the concentration of the preservative agent to the total volume of the one or more other nonaqueous ingredients ranges from about 10:1 to about 1:10. 
     
     
         9 : The method of  claim 1 , wherein the centrifugating step consists of a single step of centrifugating the composition at a speed below about 4500 g. 
     
     
         10 : The method of  claim 1 , wherein the centrifugating step consists of a single step of centrifugating the composition at a speed below about 2500 g. 
     
     
         11 : The method of  claim 1 , wherein the centrifugating step consists of a single step of centrifugating the composition at a speed of at least about 500 g. 
     
     
         12 : The method of  claim 1 , wherein the centrifugating step consists of a single step of centrifugating the composition at a speed of at least about 1500 g. 
     
     
         13 : The method of  claim 1 , wherein the total time of all centrifugation is below about 18 minutes. 
     
     
         14 . The method of  claim 1 , wherein the method is free of any centrifugating at two speeds that differ by a factor of at least about 5:1 (e.g., 7:1 or about 10:1). 
     
     
         15 . The method of  claim 14 , wherein (i) either or both of the centrifugating or analyzing steps occurs within 14 days after the blood sample is drawn, (ii) either or both of the centrifugating or analyzing steps occurs without freezing the blood sample (e.g. to a temperature colder than about −30° C. (more preferably colder than about −70° C.)); or both (i) and (ii). 
     
     
         16 . A composition including the plasma, the preservative agent, which is produced by the method of  claim 1 . 
     
     
         17 : A screening method for the identification of a characteristic of a target nucleic acid in a biological sample, comprising the steps of:
 a. collecting a biological sample having at least one first phase dispersed within at least one second phase;   b. modifying a characteristic of the first phase or the second phase for increasing the rate of phase separation between the first phase and the second phase during centrifugation of each of a plurality of individual cells within the biological sample   c. continuously centrifugating the biological sample at a speed of least about 1000 g for at least about 5 minutes to form an isolated plasma that includes at least one target nucleic acid for further analysis;   d. removing at least a portion of the isolated plasma for further analysis;   wherein the method is free of any second centrifugating step after the removing step d.   
     
     
         18 : The method of  claim 17 , wherein the characteristic modified is a surface energy characteristic, a surface area characteristic, a size characteristic, a density characteristic, or any combination thereof. 
     
     
         19 : The method of  claim 17 , wherein the density is modified by increasing the density of the plurality of blood cells by at least about 10%. 
     
     
         20 : The method of  claim 17 , wherein the density is modified by decreasing the density of the plurality of blood cells by at least about 10%.