CN101284159A

CN101284159A - Metal fibril electrode array producing method for optic nerve stimulation

Info

Publication number: CN101284159A
Application number: CNA2008100381968A
Authority: CN
Inventors: 隋晓红; 王卫峻; 孙晓东; 任秋实
Original assignee: Shanghai Jiaotong University
Current assignee: Shanghai Jiaotong University
Priority date: 2008-05-29
Filing date: 2008-05-29
Publication date: 2008-10-15
Anticipated expiration: 2028-05-29
Also published as: CN101284159B

Abstract

The invention relates to a making method of a metal micro-wire electrode array used for optic nerve stimulation. The method comprises the following steps: in step one, insulating layers at the two ends of a metal wire are stripped; in step two, an electrochemical corrosion loop is utilized to erode the exposed end of the metal wire; after the metal wire is separated from a liquid level, a switch is disconnected, and then the metal wire is taken out; in step three, a plurality of eroded metal wires are selected and inserted into a punched plastic base, partial metal wires are exposed, and are fixed by epoxide resin AB glue, and the metal wires and an external circuit connector are connected by adopting lacquered wires; in step four, the metal micro-wire electrode array is put in a plastic mould and is cast by medical silicone adhesive, and a microelectrode is taken out after solidification, so that a Pt-Ir alloy micro-wire electrode array which is applied to the optic nerve stimulation is obtained. The making method can lead an electrode to have good biocompatibility, and the made electrode is suitable for penetrating into the inner part of biological tissues and the long-term engraftment in vivo.

Description

Metal fibril electrode array producing method for optic nerve stimulation

Technical field

What the present invention relates to is the method for making its electrode in a kind of biomedical engineering technology field, particularly a kind of metal fibril electrode array producing method for optic nerve stimulation.

Background technology

Visual system is and complicated biosystem, because gene pathological changes or extraneous damage all may influence or block the transmission of visual signal, for sustaining damage because of optic nerve, retina or brain or causing the handicapped patient of vision, also there are not effective medicine or operation method to help them to regain vision so far by some inherited genetic factors generation pathological changes.In recent years, Therapeutic Method such as photodynamics, gene, medicine in controlling blind research, have been used, but what also do not have various fundus oculi diseases such as effective clinical treatment measure, particularly retinitis pigmentosa (RP), age-related macular degeneration (AMD) and a wound etc. reason caused blindly all lacks effective treatment measure at present.According to the characteristics of visual system, theoretically, carry out electricity irritation at any place of looking the road and all may cause vision.The position that vision prosthesis is implanted according to microelectrode generally can be divided on visual cortex prosthese, optic nerve prosthese, the retina implant under the implant and retina, promptly all may realize the vision reparation by electrode stimulating visual cortex, optic nerve or retina.As the unique physical channel of biological nervous system with artificial electronic equipment, the performance quality of implanted neural microelectrode has directly determined the effectiveness that vision is repaired.With regard to the reparation of optic nerve vision,, need development to thrust the metal fibril electrode array of formula in order to improve spatial resolution to optic nerve stimulation.

Find through literature search prior art, people such as Hirokazu Takahashi were IEEETRANSACTIONS ON BIOMEDICAL ENGINEERING (IEEE biomedical engineering periodical) (2005,5 phases, the 952-956 page or leaf) (" Easy-to-Prepare Assembly Array of TungstenMicroelectrodes ") (making of tungsten filament microelectrode) delivered on, propose based on substrate of glass in this article in conjunction with electric spark, the technology that sandblasts is made the tungsten filament microelectrode, concrete grammar is for adopting electric spark, the technology that sandblasts is transferred to the etching figure on the substrate of glass on the polystyrene, with its fixed structure as the tungsten filament microelectrode, its deficiency is: its technology is made complicated, tungsten filament is directly received external interface, make the microelectrode size increase like this, be not easy to implant for a long time; In addition, the physicochemical characteristics of tungsten material has limited its biocompatibility.

Summary of the invention

The present invention is directed to above-mentioned the deficiencies in the prior art, a kind of metal fibril electrode array producing method for optic nerve stimulation has been proposed, its Pt/Ir alloy silk and low tension chemical attack technology of adopting the polytetrafluoroethylene insulation to have good biocompatibility are combined, make optic nerve implanted multichannel microelectrode.

The present invention is achieved through the following technical solutions, comprises following concrete steps:

Step 1, stripping metal silk two end portions insulating barrier.

Described tinsel is the platinoiridita silk.

Described insulating barrier is polytetrafluoroethylene or C type Parylene.

Step 2, tinsel one end that utilizes the corrosion of electrochemical corrosion loop to expose after tinsel breaks away from liquid level, cuts off switch, promptly is removed.

Step 3 is chosen the tinsel that many root-rot erosions finish, is inserted on the plastic base of punching, and the exposed portions serve tinsel, and adopt epoxide resin AB glue to fix, and adopt enamel-covered wire to connect tinsel and external circuit adapter.

Described plastic base is the anchor clamps of fixing many one metal wires.

Step 4 is placed on this metal fibril electrode array in the mould of plastics, and cast medical silica-gel binding agent, after the curing, takes out microelectrode, just obtains being suitable for the platinumiridio silk microelectrode array of optic nerve stimulation.

Described silica adhesive is the biocompatibility good material, can carry out normal temperature cure, and one pack system need not to stir.

Compared with prior art, the present invention has following beneficial effect: the present invention adopts platinumiridio as the stimulating micro electrode material, make full use of the characteristics at electrochemical corrosion modified metal tip,, made optic nerve and thrust the formula multichannel microelectrode in conjunction with the mould of machining.The registration of the strict control corrosion of manufacturing process voltage swing, corrosive liquid concentration and ammeter, can improve the concordance of metal fibril structure, its impedance variation scope is ± 3%, employing has the polytetrafluoroethylene of good biocompatibility or C-Parylene as insulating barrier, the entire electrode structure has certain radian simultaneously, can closely paste the eyeball rear wall, be fit to intravital long-term implantation.

Description of drawings

Fig. 1 is an electrochemical corrosion of the present invention loop sketch map.

Fig. 2 is the perspective view of metal fibril electrode of the present invention.

Fig. 3 is a metal fibril electrode encapsulating mould sketch map of the present invention.

The specific embodiment

Below in conjunction with accompanying drawing embodiments of the invention are elaborated: present embodiment has provided detailed embodiment and process being to implement under the prerequisite with the technical solution of the present invention, but protection scope of the present invention is not limited to following embodiment.

Step 1 is got the platinoiridita silk that length is about the tape insulation layer of 2cm, uses meticulous blade to divest tinsel two ends each 3mm of insulating barrier and 200 μ m at microscopically.The platinoiridita silk exposes the end of 3mm to be clamped by alligator clamp, and the other end is waited until and immersed the NaOH corrosive liquid.

Step 2, the transformator 1 that is connected in series, ammeter 5, switch 4 and carbon-point 2, NaOH corrosive liquid 3 and treat that corrosive platinoiridita silk 6 constitutes the electrochemical corrosion loops, as shown in Figure 1.Near the liquid level wire segments should keep vertical with liquid level as far as possible, tilts to occur inhomogeneous with tapered after avoiding occurring corroding because of angle.Submergence needs accurately control, extracts 1ml left and right sides NaOH solution out with syringe, and when the platinoiridita silk was about to immersed in liquid level, closed electrochemical corrosion circuit switching was used syringe instead and slowly injected, the about 0.02ml of each one little lattice.Observe the ammeter reading simultaneously, when from 0 saltus step to a certain registration (generally being no more than 30mA), stop to inject electrolyte, electrochemical corrosion course begins.On the ammeter electric current drop to zero the time, corrosion process finishes.Can observe, there is small size swing all the time in current value in the decline process, and general trend diminishes, and (below the 10mA) saltus step is extremely zero in the lower then.This moment, electrochemical corrosion course finished, and cut-off switch takes out the platinumiridio silk.

Step 3 is chosen the tinsel that many root-rot erosions finish, is inserted on the plastic base of punching, and exposed portions serve tinsel 11, and adopt epoxide resin AB glue fixing metal silk.The end that the enamel-covered wire of insulating barrier is removed at two ends twines the exposed ends of not corroding wiry, and the other end is received the metal pins of external circuit adapter.

Step 4, this metal fibril electrode array is wound with enamel-covered wire one end and enamel-covered wire is placed in the mould of plastics, and cast medical silica-gel binding agent, after the curing, take out microelectrode array, can realize encapsulation, obtain being suitable for metal fibril electrode array after the encapsulation of optic nerve stimulation, as shown in Figure 2 microelectrode array.

Described encapsulation back metal fibril electrode array, wherein the thickness 7 of enamel-covered wire part is 2mm, and width 8 is 3mm, and radius of the radian is 10mm; Wire array partial width 9 is 2mm.

As shown in Figure 3, the arcuate groove part 12 of described mould of plastics, radius is 10mm, width is 2mm, dark 2mm, the enamel-covered wire of placement metal fibril array in it; Projected square part 13, length and width are respectively 2mm, and the degree of depth is 2mm, places the metal fibril electrode array part in it, and corrosive tinsel tip is up.

Compared with prior art, the present invention has following beneficial effect: the present invention adopts platinumiridio as stimulation The microelectrode material takes full advantage of the characteristics at electrochemical corrosion modified metal tip, in conjunction with the mould of machining, Made optic nerve thrust-type multichannel microelectrode. Manufacturing process is strictly controlled the corrosion voltage swing, corrosive liquid is dense Degree and the registration of ammeter can improve the uniformity of metal fibril structure, and its impedance excursion is ± 3%, Employing has the teflon of good biocompatibility or C-Parylene as insulating barrier, simultaneously whole electrode knot Structure has the eyeball radian, can closely paste the eyeball rear wall, is fit to the long-term implantation in the body.

Claims

1, a kind of metal fibril electrode array producing method for optic nerve stimulation is characterized in that, comprises the steps:

Step 1, stripping metal silk two end portions insulating barrier, wherein: described tinsel is the platinoiridita silk, described insulating barrier is polytetrafluoroethylene or C type Parylene;

Step 2, tinsel one end that utilizes the corrosion of electrochemical corrosion loop to expose after tinsel breaks away from liquid level, cuts off switch, promptly is removed;

Step 3 is chosen the tinsel that many root-rot erosions finish, is inserted on the plastic base of punching, and the exposed portions serve tinsel, and adopt epoxide resin AB glue to fix, and adopt enamel-covered wire to connect tinsel and external circuit adapter;

Step 4, the metal fibril electrode array that step 3 is obtained is placed in the mould of plastics, and cast medical silica-gel binding agent, after the curing, takes out microelectrode, just obtains the optic nerve stimulation metal fibril electrode array.

2, metal fibril electrode array producing method for optic nerve stimulation according to claim 1 is characterized in that, described stripping metal silk two end portions insulating barrier is meant and adopts metal blade to strike off platinumiridio silk insulation layer at microscopically.

3, metal fibril electrode array producing method for optic nerve stimulation according to claim 1, it is characterized in that, described electrochemical corrosion loop is by transformator, ammeter, switch and carbon-point, NaOH corrosive liquid and treat that corrosive platinoiridita silk is connected in series and constitute, adopt static corrosion, corrosion finishes, and tinsel breaks away from liquid level automatically.

4, metal fibril electrode array producing method for optic nerve stimulation according to claim 1 is characterized in that, described plastic base is the anchor clamps of fixing many one metal wires.

5, metal fibril electrode array producing method for optic nerve stimulation according to claim 1 is characterized in that, described exposed portions serve tinsel is meant and exposes the 1mm-1.5mm tinsel.

6, metal fibril electrode array producing method for optic nerve stimulation according to claim 1 is characterized in that, described employing epoxide resin AB glue is fixed, and is meant with the coating of epoxide resin AB glue, treats room temperature full solidification after 5 minutes.