Preparing biological samples for analysis

Abstract

Methods and devices for preparing a biological sample for analysis are described. The biological sample from an organism has at least macromolecule having a primary structure that naturally degrades after the sample is removed from the organism. The method includes causing the biological sample to adopt a shape to permit rapid and uniform heating. The shaped sample is then rapidly and uniformly heated, thereby altering a secondary structure of the macromolecule while preserving its primary structure.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This is a continuation of U.S. National Phase application Ser. No. 11 / 996,545 filed 27 Aug. 2006; which claims the benefit of priority to International Application No. PCT / SE2006 / 000979 filed 27 Aug. 2006; which is a continuation-in-part of U.S. application Ser. No. 11 / 212,454, filed 26 Aug. 2005; each of which is incorporated herein by reference in its entirety.STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT[0002]Not Applicable.INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED IN COMPUTER READABLE FORMAT (CRF)[0003]Not Applicable.FIELD OF THE INVENTION[0004]The present invention relates to methods and apparatus for preparing a biological sample for analysis. The invention more particularly relates to methods and apparatus for heating a biological sample soon after it is extracted so that the primary structures of proteins in it are not degraded.BACKGROUND OF THE INVENTION[0005]It is key to any analysis of a biological samp...

AI Technical Summary

Benefits of technology

The present invention is a method for preparing a biological sample for analysis. The method involves shaping the sample by causing it to adopt a shape that allows for uniform and rapid heating, which disrupts the secondary structure of the sample without affecting its primary structure. This helps to shorten the time needed to reach a disrupted secondary structure and minimizes degradation of certain constituents of the sample. The heating also reduces proteolytic activity by at least 70%. This method, which can be performed immediately after taking the sample, has several advantages, including enabling the preservation of the protein's primary structure, minimizing degradation of neuropeptides and proteins, and making it possible to compare the content and levels of proteins and peptides from different samples without sacrificing the entire organism.

Problems solved by technology

Sample degradation, however, is both hard to impede, and hard to detect.

The result is that many analyses miss the presence of species that have degraded long before the analysis is carried out; correspondingly, such analyses may in fact identify degradation products of critical components in place of the original components.

Despite their ubiquity, proteins are extremely sensitive to their environments and thus are not always easy to detect and to identify because they can degrade very quickly.

Once an organism dies, or once a sample of tissue is extracted from a-living organism, the regulatory balance of the organism or in the sample is lost and key proteins start to break down.

For example, some proteins whose natural role is to digest other proteins (a “proteolytic” function), and whose natural levels are kept in check while an organism is alive, may go out of control after death.

However, the study of tissue samples from patients or model organisms usually exposes the samples to a certain period of oxygen and nutrient depletion before homogenization and protease inactivation occurs.

Use of aldehyde solutions is problematic because it doesn't arrest natural degradation of proteins (though it is somewhat effective at maintaining large-scale structure of tissues).

Microwave irradiation is problematic because it is generally non-uniform, that is, some parts of the sample reach a temperature that is high enough to cause sample breakdown.

Furthermore, microwave irradiation has formerly been applied to living (non-human) subjects as part of a sacrificial protocol and thus has yet to be established as a tool for analyzing samples that have been extracted from subjects, both human and non-human.

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