Methods and apparatus for processing temperature sensitive materials

Abstract

A method and system (10) for selectively removing one component of a material thereby concentrating other components of the material are disclosed. The material is cooled to below the melting temperature of the material to form a supercooled liquid phase with heat transfer plate with cooling channels (20). Ultrasonic energy from ultrasonic drivers (42) is applied to the material to form solid phase crystals of the component to be removed. These crystals are removed to leave the concentrated product. The ultrasonic energy prevents the growth of dendrites on the crystals, resulting in the formation and removal of small crystals of the component to be removed without damage to or removal of the remaining components. Methods and apparatuses for cryoprecipitation and chromatography are also disclosed.

Description

BACKGROUND OF THE INVENTION [0001] This application claims priority to U.S. Provisional Patent Application Ser. No. 60 / 101,307, filed on Sep. 21, 1998.FIELD OF THE INVENTION [0002] The present invention relates generally to a method and system for concentrating liquid materials. The invention relates more specifically to a method and system for selective removal of one or more components of a temperature-sensitive, multi-component material to form a product having an increased concentration of one or more other components of the material. The present invention further relates to methods and apparatus for processing temperature-sensitive materials, such as blood plasma. In particular, the present invention relates to methods and apparatus for concentrating temperature-sensitive materials, such as blood plasma, and for processing temperature-sensitive materials, such as blood plasma, by cryoprecipitation and / or chromatography. DESCRIPTION OF THE BACKGROUND [0003] Plasma is the straw-c...

AI Technical Summary

Benefits of technology

[0061] Briefly described, in preferred form, the present invention comprises a method and system for concentrating materials. The method and system of the present invention are particularly suited to the concentration of temperature-sensitive materials, but can also be utilized for the concentration of materials that are not temperature-sensitive. According to the preferred forms of the present invention described in greater detail herein, the method and system of the present invention are applied to concentrate a material comprising at least a first component and a second component. At least a portion of the first component of the material is removed to form a product having an increased concentration of the second component, relative to the concentration of the second component in the initial material. The method and system of the present invention are applicable to concentration of materials including, without limitation: biological materials such as plasma, and / or other blood constituents; pharmaceuticals; chemicals; laboratory testing diagnostics; and food products.

[0062] One aspect of the invention provides a method of concentrating a solution or other material comprising at least a first component and a second component, to form a product having an increased concentration of one of the components. The method preferably comprises cooling at least a portion of the material to a temperature at or below the melting point of the solution, said portion containing the first component in liquid phase. The method preferably further comprises applying ultrasonic energy to at least the cooled portion of the material to form crystals of the first component in solid phase. The method preferably also comprises removing the crystals from the material to form the concentrated product. The product can be the material remaining after removal of the crystals and having an increased concentration of the second component or, conversely, can be the removed crystals having an increased concentration of the second component.

[0063] In another aspect, the present invention comprises a system for concentrating a material comprising at least a first component and a second component, to form a product having an increased concentration of one of the components. The system preferably includes a heat transfer device for cooling at least a portion of the material to a temperature at or below the melting point of the material, said portion containing the first component in liquid phase. The system preferably also includes an ultrasonic energy source for applying ultrasonic energy to at least the cooled portion of the material to form crystals of the first component in solid phase. The system preferably also includes means for collecting the crystals from the material to form the product. The product can be the material remaining after removal of the crystals and having an increased concentration of the second component or, conversely, can be the removed crystals having an increased concentration of the second component.

[0064] In another aspect, the present invention comprises a container for containing a quantity of material during separation of a first component from the material to form a first product having an increased concentration of the first component and a second product having an increased concentration of a second component of the material. The container preferably comprises a flexible wall portion enclosing a treatment chamber for allowing heat transfer between an external heat transfer device and the material, and allowing ultrasonic energy transmission from an external energy source into the material. The container preferably further comprises a collection chamber for collecting a removed portion of the first product. The container preferably also comprises a product chamber for collecting the second product.

[0065] The system and method of the present invention may find application in a number of fields, for example: concentration of biological materials such as plasma and other blood constituents; concentration of pharmaceuticals; concentration of chemicals; concentration of laboratory test specimens to increase recognition of low concentration components; and concentration of food products.

Problems solved by technology

However, it is not possible to obtain enough material to meet these demands.

For example, the storage and shipment of blood products typically requires expensive refrigeration equipment.

Previously known material concentration methods have been found to be less than fully successful for many applications.

In particular, temperature-sensitive materials are often damaged by known material concentration methods.

For example, forced evaporative and distillation methods of concentration, which typically involve the application of heat to the material to be concentrated, can irreversibly denature proteins or otherwise damage the product.

Previously known cryoprecipitation methods of concentration, which typically involve freezing the entire quantity of material to be concentrated, can likewise damage temperature-sensitive products.

Previously known filtration methods of material concentration typically suffer inefficiencies due to clogging of the filter media, necessitating frequent replacement or cleaning of the filter.

Previously known methods and systems for concentrating also suffer from low yields and inefficiencies.

For example, pump and line losses often consume a substantial quantity of concentrate in known methods and systems.

Conventional cryoprecipitation techniques, however, suffer from long processing times and poor yields; these limits are indeed some of the prime motivations for the concentrator.

There are, however, four major factors that act against these ideal conditions.

First, the sample may be so large that the starting conditions are not well defined, i.e., part of the sample may be subject to solvent motion, while the rest of the sample sees no treatment.

Second, molecular diffusion of the solute under the action of the increasing concentration gradient tends to spread the material in all directions.

Third, eddy diffusion due to irregularities in the media can also spread the solute in all directions.

Fourth, the resistance of the media to mass transfer can hinder local equilibration.

The net effect of these, and other lesser factors, is to spread the components (i.e., the components migrate as broad, possibly overlapping bands as opposed to narrow, resolved bands), thereby reducing the resolution of the system.

These techniques, which include the use of high pressure, rotation, ion exchange, affinity, etc., are often quite successful, but are expensive, complicated, and require long processing times. These problems are particularly severe for high molecular weight components, such as blood plasma proteins.

Even in this state-of-the-art facility, however, the process is still quite involved and lengthy.

This very long time is in fact the underlying problem behind recent shortages of various immunoglobulins in the United States, shortages so severe that FDA has relaxed some safety standards.

Images