Apparatus, system and method for performing automated centrifugal separation

Abstract

Systems, methods and devices are provided for the automated centrifugal processing of samples. In some embodiments, an integrated fluidic processing cartridge is provided, in which a centrifugation chamber is fluidically interfaced, through a lateral surface thereof, with a microfluidic device, and wherein the integrated fluidic processing cartridge is configured to be inserted into a centrifuge for centrifugation. A cartridge interfacing assembly may be employed to interface with the integrated fluidic processing cartridge far performing various fluidic processing steps, such as controlling the flow of fluids into and out of the centrifugation chamber, and controlling the flow of fluids into the microfluidic device, and optionally for the further fluidic processing of fluids extracted to the microfluidic device. The integrated fluidic processing cartridge may include a supernatant chamber the extraction of a supernatant thereto, and a diluent chamber for diluting a suspension collected in the centrifugation chamber.

1 . A method of processing a sample containing microbial cells, the method comprising:
 forming, within a centrifugal processing chamber of a fluidic device, a mixture comprising the sample and a pre-treatment reagent;   employing an automated centrifugation and fluid processing system to perform autonomous operations on the fluidic device, the automated centrifugation and fluid processing system comprising a closure mechanism for maintaining the centrifugal processing chamber in a closed state during centrifugal processing of the fluidic device, the autonomous operations comprising:
 (a) performing centrifugation of the fluidic device, thereby separating the microbial cells from a first supernatant; 
 (b) removing at least a portion of the first supernatant from the centrifugal processing chamber; 
 (c) dispensing a wash buffer into the centrifugal processing chamber; 
 (d) performing centrifugation of the fluidic device, thereby separating the microbial cells from a second supernatant; and 
 (e) removing at least a first portion of the second supernatant from the centrifugal processing chamber; 
   resuspending the microbial cells to obtain a purified and concentrated microbial suspension; and   employing the microbial suspension to perform at least one downstream microbial assay.   
     
     
         2 . The method according to  claim 1  wherein steps (c) to (e) are repeated one or more times. 
     
     
         3 . The method according to  claim 1  wherein the at least one downstream microbial assay comprises identification by matrix assisted laser desorption/ionization (MALDI) analysis. 
     
     
         4 . The method according to  claim 1  wherein the at least one downstream microbial assay comprises identification by nucleic acid amplification and detection. 
     
     
         5 . The method according to  claim 4  wherein steps (c) to (e) are repeated a sufficient number of times to reduce a concentration of an assay interferent substance by factor of at least 10,000. 
     
     
         6 . The method according to  claim 4  wherein steps (c) to (e) are repeated a sufficient number of times to reduce a concentration of an assay interferent substance by factor of at least 100,000. 
     
     
         7 . The method according to  claim 1  wherein the at least one downstream microbial assay comprises antimicrobial susceptibility testing. 
     
     
         8 . The method according to  claim 1  wherein the sample comprises blood cells and the pre-treatment reagent is configured to facilitate lysis of the blood cells. 
     
     
         9 . The method according to  claim 1  wherein the sample comprises whole blood. 
     
     
         10 . The method according to  claim 1  wherein the sample is a blood culture sample. 
     
     
         11 . The method according to  claim 1  wherein the closure mechanism comprises a robotic actuator configured to engage with the fluidic device such that the centrifugal processing chamber is closed during centrifugation. 
     
     
         12 . The method according to  claim 1  wherein the fluidic device further comprises a wash buffer chamber and a waste chamber, wherein fluidic communication between the wash buffer chamber and the centrifugal processing chamber is controllable by actuation of a first valve, and wherein fluidic communication between the waste chamber and the centrifugal processing chamber is controllable by actuation of a second valve, and wherein the closure mechanism is actuated to prevent, during centrifugation of the fluidic device, fluid communication between the centrifugal processing chamber and the wash buffer chamber and between the centrifugal processing chamber and the waste chamber, by respective actuation of the first valve and the second valve. 
     
     
         13 . An automated centrifugation and fluid processing system comprising:
 a fluidic device comprising a centrifugal processing chamber;   a centrifugation subsystem capable of centrifugal processing of said fluidic device;   a fluid processing subsystem; and   a closure mechanism for maintaining said centrifugal processing chamber in a closed state during centrifugal processing of said fluidic device;   control circuitry operatively coupled to said centrifugation subsystem, said fluid processing subsystem and said closure mechanism to perform operations on said fluidic device after a mixture containing microbial cells has been added to said centrifugal processing chamber of said fluidic device, the operations comprising:
 (a) controlling said centrifugation subsystem to perform centrifugation of said fluidic device, thereby separating the microbial cells from a first supernatant; 
 (b) controlling said fluid processing subsystem to remove at least a portion of the first supernatant from said centrifugal processing chamber; 
 (c) controlling said fluid processing subsystem to dispense a wash buffer into said centrifugal processing chamber; 
 (d) controlling said centrifugation subsystem to perform centrifugation of said fluidic device, thereby separating the microbial cells from a second supernatant; and 
 (e) controlling said fluid processing subsystem to remove at least a first portion of the second supernatant from said centrifugal processing chamber. 
   
     
     
         14 . The system according to  claim 13  wherein said control circuitry is configured to perform additional operations such that steps (c) to (e) are repeated one or more times. 
     
     
         15 . The system according to  claim 13  wherein said control circuitry is configured to perform additional operations such that steps (c) to (e) are repeated a sufficient number of times to achieve a dilution factor of at least 10,000. 
     
     
         16 . The system according to  claim 13  wherein said control circuitry is configured to perform additional operations such that steps (c) to (e) are repeated to achieve a dilution factor of at least 100,000. 
     
     
         17 . The system according to  claim 13  wherein said closure mechanism comprises a robotic actuator configured to engage with said fluidic device such that said centrifugal processing chamber is closed during centrifugation. 
     
     
         18 . The system according to  claim 13  wherein said fluidic device further comprises a wash buffer chamber and a waste chamber, and wherein fluidic communication between said wash buffer chamber and said centrifugal processing chamber is controllable by actuation of a first valve, and wherein fluidic communication between said waste chamber and said centrifugal processing chamber is controllable by actuation of a second valve, and wherein said control circuitry is further configured to control said closure mechanism to prevent, during centrifugation of said fluidic device, fluid communication between said centrifugal processing chamber and said wash buffer chamber and between said centrifugal processing chamber and said waste chamber, by respective actuation of said first valve and said second valve.