Implantable measuring device

The present invention relates to a diagnostic device for determining analytical parameters that essentially consists of a plurality of identical and / or different units of measurement for the determination of an analytical Parameter in which a signal is generated which in a certain Proportion to the quantity to be determined and which falls through appropriate transfer action to a receiver located outside the body becomes.

An implantable diagnostic devices have been described, for. Example, as Components of implantable insulin pumps. Essentially, there are such Devices of an implantable measuring chamber in which a biosensor an analyte dependent Signal which seinerseit for controlling the insulin pump serves. These devices must be periodically exchanged when the insulin supply is exhausted. Since this exchange is relatively frequently takes place, is the Austauschinterval often shorter than the service life of the biosensors.

A disadvantage of the previous methods, and probably one reason why the previously methods for glucose determination in conjunction with insulin pumps not have been transferred to other parameters, the problem is caused the would if the biosensors over a longer period in contact with blood are and then its function by deposits such. as fat or protein-containing deposits (Clot) impaired or even impossible.

In particular, methods for the determination of coagulation parameters that naturally often accompanied by a clot formation, be as not promising considered.

The object of the present invention is based was to provide a diagnostic to provide apparatus which enables the intervals between the Replacing the devices to significantly increase.

Surprisingly, it was found that the device according to the invention containing both Einzelmeßkammer, and in a multiple measuring chamber Apparatus advantageously used for the determination of coagulation parameters can be.

The device according to the invention thus consists of one or more measuring chambers, in turn, consists essentially of three parts, namely the actual Measurement chamber, a fact excellent cannula, in turn, into a vessel are projects, detected in the liquid volume of analytical parameters should. Further, associated with each measuring chamber - or even at all measuring chambers together - a signal transmission unit. The tube-side end of the cannula can advantageously be completed by a filter through the but the analytes allows cells restrains. The cannulas are further provided with a flap provided that operated by the action of an extracorporeal signal can be.

The diagnostic device is advantageously additionally provided with a device provided for storing the measuring signals, which are then retrieved as needed can.

A preferred embodiment of the measuring chamber is shown in figure 2.

Advantageously, a plurality of measuring chambers is a diagnostic Device combined with the number of Einzelmeßkammern preferably Is 20 to 50. The number as such is not critical, it is based on a Determining a week, so a number of 50 ± 10 appears particularly advantageous, since in this case an exchange per year is sufficient.

The method and apparatus according to the invention can be used both for flow measurements as be equipped for single determinations. By the possibility of contactless signal transmission may advantageously both stationary as well as outpatients without an additional restriction of movement the patients are used. The types of signal transmission are the Skilled known. The structure of an embodiment of the device is in 1 shown FIG.. The structure of a special measuring chamber is shown in Fig. 2A. The preparation is sufficiently smaller measuring chambers with at the skilled worker known methods possible.

Of particular importance is the closure of the measuring chambers. Here can advantageously magnetically operable shutters, take the 2 solid states can (flip-flops) are used. In FIG. 2, B is an arrangement of several measuring chambers shown. The light supply to the individual measuring chambers can separately as either correspondingly small, for each measurement chamber arranged light sources such as light emitting diodes, or via corresponding light guides done.

Advantageously, each measuring chamber the one or more necessary for the reaction Reagent (s), eg thromboplastin for a PT (thromboplastin time, "Prothrombin time) determination. With the usual in the coagulation applied Determination method is the innovative technology difficult to realize. Advantageously, a new technology is applied, in the following will be described.

Thus, for. Example, singlet oxygen emitting particles (SSEP), the z. B. are EP 0515194 describes used. This SSEPs be in the applied measurement chamber on a conductive surface, for example made of carbon together with the analyte-specific reagents. In the measuring chamber extends a Light source that irradiates a light, which is suitable to excite the SSEPs. If clotting occurs, the mobility of SSEPs is changed, usually restricted, thereby to SSEPs accumulate the conductive surface and it produces a measurable current flow (see also Fig. 3).

An analogous method can be applied for immunological determinations, wherein a specific binding partner immobilized on the conductive surface , and by the analyte SSEPs, also specific with one, for the analyte Binding partners are coated, bonded in the vicinity of the conductive surface , which in turn to a measurable change in the current flow leads.

An advantageous embodiment can be carried out as follows:

A device consisting of the elements of a measuring unit, a signal-processing Unit and a cannula is implanted under the skin so that the Cannula projects into a vessel. The units are by means of Micro technology as For example, in the manufacture of integrated circuits (chip technology) uses are produced and characterized so small that they known endoscopic techniques can be implanted. For testing, a launched external receiver and the power to measure transmitted conductively. Simultaneously, the measurement signals or results are transmitted to the receiver and can be called up there.

The measuring unit consists of discrete measuring chambers which individually closed by valves can be and can be used only once, and a Pumping device in connection to the cannula, and, if applicable. To a reservoir with physiological NaCl to flush the cannula. Further contains the measuring unit a light generator, such as a microlaser, and power lines for the disposal and Processing of the measurement signal. The measuring chamber contains a miniaturized diode is connected via an optical waveguide with the central light generator. In the Measuring chamber are used to detect the plasma protein or the Coagulation Analysis necessary reagents. The process for preparing the discrete components, such. as valves or pumps are known to those skilled in the known.

Detection of the reaction is carried out via a novel combination of sensitizer beads from the LOCI technology with an amperometric sensitive circuit board. By excitation with light of oxygen free radicals are generated, which on the printed circuit board produce a measurable signal. When a clot this arises immobilization preferably near the circuit board. The free solution can be held by a stirrer in motion. For immunochemical reactions are immobilized on the Obertläche corresponding binding partner. By Binding of the sensitizer beads to the analyte to be detected, which to the binding partner the surface is bonded, the sensitizer beads in the be brought close to the circuit board, so that more likely a transmission of charge (oxygen radicals) occurs. The measuring signal is thus the concentration of analyte proportional. Alternatively, the common reagents LOCI system consisting of Sensitizer and acceptor beads are used. In the measuring chamber is located then a light receiver in place of the circuit boards.

The signal verbeitende unit includes an arithmetic processor and a transducer for transmission of results, and other electrical units for energy reception.

The cannula may contain filters that the exclusion of cellular components ensure the blood so that plasma is used for analysis. through rear Rinse with saline can by measurement Access channels, cannula and filters are cleaned.