Mobile rapid test system for nucleic acid analysis

Abstract

A mobile rapid test system for nucleic acid analysis. A method comprising the steps of amplification of the nucleic acids by means of rapid-PCR technology, conversion of a double-stranded amplification product into a single-stranded DNA fragment, hybridization with a labeled probe and detection of the nucleic acids on a lateral-flow test strip. A device comprising a reaction cavity which preferably consists of a thin film, inlet and outlet openings for the reaction cavity, one or more heatable sample blocks which are connected to miniaturized cooling bodies and a window for reading off the result. The lateral-flow test strip is a component of the mobile rapid test system. Operation of the instrument system requires no external power source, but only batteries or a rechargeable battery.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application claims benefit under 35 U.S.C. §365(c) and 35 U.S.C. §120 to PCT / EP2008 / 068197, filed Dec. 22, 2008, which claims priority to Germany 10 2007 062 441.9, filed Dec. 22, 2007. Both of these documents are hereby incorporated by reference in their entireties.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]A mobile equipment system for gene diagnostics.[0004]2. Description of the Related Art[0005]The examination of diagnostically relevant biological samples, such as serum, plasma, blood, swab samples, or organ smears, for the detection of infectious pathogens has gained tremendous importance in recent years. Viral infections such as HIV, HCV, or HBV are increasing worldwide. Furthermore, bacterial infections are also increasing again, among other things also as the result of climatic changes. The occurrence of new, deadly infectious diseases having an extremely high infection potential (SARS, bird flu) shows mo...

AI Technical Summary

Benefits of technology

[0015]The invention was based on the task of developing a novel mobile gene-diagnostic rapid test system (combination of hardware and reagents), which is supposed to be easy to operate, allows extremely rapid diagnostic information, and is inexpensive both with regard to the device and with regard to the test to be performed. Therefore, the possibility of being able to carry out diagnostics of infectious diseases in developing countries, without qualitative restrictions, is also supposed to be created.

Problems solved by technology

These tests are tied to extremely expensive equipment technology prerequisites, and also expensive reagents.

These methods can only be carried out by trained technical personnel in special laboratories.

On-site diagnostics are not possible.

New generations of integrative system solutions (combinations of nucleic acid isolation, amplification, and chip detection) for mobile on-site diagnostics are in development, but not in a stage of successful marketing.

Furthermore, these systems often focus on the sector of military diagnostics, and, in analogy to the “traditional REAL-TIME PCR” methods, are also very expensive, in terms of both devices and reagents.

However, these receptacles all have a very thick wall thickness (approximately 0.2 mm-0.35 mm), which opposes good heat transfer from the heated sample block into the sample, as a very great resistance.

200) are not able to significantly improve this condition.

The technical prerequisites (heating and cooling) for rapid processing of the temperatures in PCR are implemented technically, but the efficacy is greatly impaired, because of the consumable used.

The metallic sample blocks used (aluminum, silver) in thermocyclers having a very great heat capacity furthermore ensure that rapid temperature changes in the sample are impossible to implement, even when using strong heating elements.

The rapidity of existing systems on the market, which work on the basis of metallic sample blocks and injection-molded consumables, thus comes up against objective limits.

From this, it follows that because of their tremendous thermal inefficiency, miniaturized, mobile variants of these thermocyclers exceed the electrical conductivity of accessible battery technology in unacceptable manner.

However, this large glass surface area absorbs components of standard PCR batches and thus causes the reaction to become more and more inactive.

Another disadvantage in this connection is the handling of the very thin capillaries and their price.

Miniaturization and simple handling of the receptacles continues to be impossible, however.

Thus, while this reference explains that rapid PCR is supposed to be carried out, it does not, however, provide sufficient information about technical implementation.

This point also includes the fact that the consumable described there does not meet the requirements of being a cost-advantageous consumable material.

However, a disadvantage of this method is that the PCR product is not hybridized with a marked probe.

The sole detection of an amplification product in this manner is diagnostically very uncertain, however, since the required 100% specificity of the amplification product is not guaranteed.

Furthermore, there is the latent risk that false-positive results occur due to mis-priming and primer dimers.

However, the lateral-flow method does not serve to detect amplification events.

Because of the use of a large number of thermoelectric modules (“hydrogel ice valves”) and fluid pumps, a person skilled in the art recognizes that this device cannot be suitable for mobile battery operation.

These modules, which are very power-intensive, as well as the consumable design, which is not optimized, thus preclude even the possibility of mobile battery operation.

Finally, a person skilled in the art recognizes that this system cannot be used for mobile use, since the complexity of the consumable (multiple production steps, introduction of hydrogels) requires unreasonable production costs.

However, it is known to a person skilled in the art that such a detection method on a test strip is highly problematical, since specific amplification products cannot be separated from the non-specific amplificates and so-called primer dimers.

Thus, such a detection system cannot be used in diagnostics.

The inefficiency of the concept becomes evident to a person skilled in the art when the authors discuss the difficulties in achieving an acceptable cooling rate.

This makes it evident to a person skilled in the art that this chip concept makes a cost-advantageous consumable impossible.

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