AU714537C

AU714537C - Electrotransport device having reusable controller

Info

Publication number: AU714537C
Application number: AU58522/96A
Authority: AU
Inventors: Tighe M. Belden; Danny J. Cunagin; Philip C. Dretzka; Gary A Lattin
Original assignee: Alza Corp
Current assignee: Alza Corp
Priority date: 1995-05-15
Filing date: 1996-05-01
Publication date: 2001-11-08
Anticipated expiration: 2016-05-01
Also published as: IT1285873B1; ITTO960397A1; IE960331A1; ITTO960397A0; FR2734162A1; MX9708823A; NL1003109A1; AU5852296A; JPH11505158A; CN1104917C; AU714537B2; JP2006297132A; GB2317343A; NL1003109C2; JP2008100096A; DE19681392B4; CA2216731A1; CN1184433A; WO1996036394A1; DE19681392T1

Description

ELECTROTRANSPORTDEVICEHAVING REUSABLE CONTROLLER

TECHNICAL FIELD

The invention relates to electrotransport drug delivery systems having a drug containing assembly and a reusable controller having an electrically powered control circuit, the assembly and the controller being separably connected by a coupler which establishes electrical connection of the assembly to the controller.

BACKGROUND ART

The term "electrotransport" as used herein refers generally to the delivery of an agent (e.g., a drug) through a membrane, such as skin, mucous membrane, or nails. The delivery is induced or aided by application of an electrical potential. For example, a beneficial therapeutic agent may be introduced into the systemic circulation of a human body by electrotransport delivery through the skin. A widely used electrotransport process, electromigration (also called iontophoresis), involves the electrically induced transport of charged ions. Another type of electrotransport, electroosmosis, involves the flow of a liquid, which liquid contains the agent to be delivered, under the influence of an electric field. Still another type of electrotransport process, electroporation, involves the formation of transiently-existing pores in a biological membrane by the application of an electric field. An agent can be delivered through the pores either passively (i.e., without electrical assistance) or actively (i.e., under the influence of an electric potential). However, in any given electrotransport process, more than one of these processes may be occurring simultaneously to a certain extent. Accordingly, the term "electrotransport", as used herein, should be given its broadest ι possible interpretation so that it includes the electrically induced or enhanced

2 transport of at least one agent, which may be charged, uncharged, or a

3 mixture thereof, whatever the specific mechanism or mechanisms by which

4 the agent actually is transported.

5 Electrotransport devices use at least two electrodes that are in

6 electrical contact with some portion of the skin, nails, mucous membrane,

7 or other surface of the body. One electrode, commonly called the "donor" β or "active" electrode, is the electrode from which the therapeutic agent is

9 delivered into the body. The other electrode, typically termed the "counter" ιo or "return" electrode, serves to close the electrical circuit through the body. ιι For example, if the agent to be delivered is positively charged, i.e., a cation,

12 then the anode is the active or donor electrode, while the cathode serves

13 to complete the circuit. Alternatively, if an agent is negatively charged,

14 i.e., an anion, the cathode is the donor electrode. Additionally, both the

15 anode and cathode may be considered donor electrodes if both anionic and

16 cationic agent ions, or if uncharged or neutrally charged agents, are to be

17 delivered.

18 Furthermore, electrotransport delivery systems generally require at

19 least one reservoir or source of the agent to be delivered, which is typically in

20 the form of a liquid solution or suspension. Examples of such donor

21 reservoirs include a pouch or cavity, a porous sponge or pad, and a

22 hydrophilic polymer or a gel matrix. Such donor reservoirs are electrically

23 connected to, and positioned between, the anode or cathode and the body

24 surface, to provide a fixed or renewable source of one or more agents or

25 drugs. Electrotransport devices also have an electrical power source such as

26 one or more batteries. Typically, one pole of the power source is electrically

27 connected to the donor electrode, while the opposite pole is electrically

28 connected to the counter electrode. In addition, some electrotransport

29 devices have an electrical controller that controls the current applied through

30 the electrodes, thereby regulating the rate of agent delivery. Furthermore, passive flux control membranes, adhesives for maintaining device contact with a body surface, insulating members, and impermeable backing members are other optional components of an electrotransport device. All electrotransport agent delivery devices utilize an electrical circuit to electrically connect the power source (e.g., a battery) and the electrodes. In very simple devices, such as those disclosed in Ariura et al US Patent 4,474,570, the "circuit" is merely an electrically conductive wire used to connect the battery to an electrode. Other devices use a variety of electrical components to control the amplitude, polarity, timing, waveform shape, etc. of the electric current supplied by the power source. See, for example, McNichols et al US Patent 5,047,007. To date, commercial transdermal electrotransport drug delivery devices (e.g., the Phoresor, sold by lomed, Inc. of Salt Lake City, UT; the Dupel Iontophoresis System sold by Empi, Inc. of St. Paul, MN; the Webster Sweat Inducer, model 3600, sold by Wescor, Inc. of Logan, UT) have generally utilized a desk-top electrical power supply unit and a pair of skin contacting electrodes. The donor electrode contains a drug solution while the counter electrode contains a solution of a bio-compatible electrolyte salt. The "satellite" electrodes are connected to the electrical power supply unit by long (e.g., 1-2 meters) electrically conductive wires or cables. Examples of desk- top electrical power supply units which use "satellite" electrode assemblies are disclosed in Jacobsen et al US Patent 4,141 ,359 (see Figures 3 and 4); LaPrade US Patent 5,006,108 (see Figure 9); and Maurer et al US Patent 5,254,081 (see Figures 1 and 2). The power supply units in such devices have electrical controls for adjusting the amount of electrical current applied through the electrodes. Existing commercial electrotransport devices are approved for operation only by trained medical technicians. One important consideration when connecting the "satellite" electrodes to the power supply unit is to make sure that the electrodes are connected with the correct polarity, i.e., a satellite donor electrode which contains a cationic ι therapeutic agent must be connected to the positive output of the controller

2 whereas a satellite donor electrode which contains an anionic therapeutic

3 agent must be connected to the negative output of the controller. In order to

4 assist the medical technician to make the correct polarity connections,

5 two approaches have been used. In the first approach, the outputs of the

6 controller have been color coded to the appropriate satellite electrode.

7 In the second approach (used in the CF Indicator sold by ScandiPharm, Inc.), β the controller is provided with electrodes in the form of metal (e.g., stainless

9 steel) plates which are positioned on one side of the controller housing. ιo The two electrode plates have different geometric shapes (e.g., one square ιι and one circular). The drug-containing donor gel and the electrolyte-

12 containing counter gel each have a different shape which corresponds to the

13 respective electrode plate shape in order to ensure that the donor and

14 counter gels are placed in contact with the correct (i.e., correct polarity)

15 electrodes.

16 More recently, small self-contained electrotransport delivery devices

17 adapted to be worn on the skin, sometimes unobtrusively under clothing,

18 for extended periods of time have been proposed. The electrical components

19 in such miniaturized electrotransport drug delivery devices are also preferably

20 miniaturized, and may be either integrated circuits (i.e., microchips) or small

21 printed circuits. Electronic components, such as batteries, resistors, pulse

22 generators, capacitors, etc., are electrically connected to form an electronic

23 circuit that controls the amplitude, polarity, timing, waveform shape, etc. of the

24 electric current supplied by the power source. Such small self-contained

25 electrotransport delivery devices are disclosed for example in Tapper

26 US Patent 5,224,927; Sibalis et al US Patent 5,224,928 and Haynes et al

27 US Patent 5,246,418. ι There have recently been suggestions to utilize electrotransport

2 devices having a reusable controller which is adapted to be used with multiple

3 drug-containing units. The drug-containing units are simply disconnected

4 from the controller when the drug becomes depleted and a fresh drug-

5 containing unit is thereafter connected to the controller. In this way,

6 the relatively more expensive hardware components of the device

7 (e.g., batteries, LED's, circuit hardware, etc.) can be contained within the β reusable controller, and the relatively less expensive donor reservoir and

9 counter reservoir matrices can be contained in the disposable drug containing ιo unit thereby bringing down the overall cost of electrotransport drug delivery. ιι Examples of electrotransport devices comprised of a reusable controller

12 adapted to be removably connected to a drug-containing unit are disclosed in

13 Sage, Jr. et al, US Patent 5,320,597; Sibalis, US Patent 5,358,483;

14 Sibalis et al, US Patent 5,135,479 (Fig. 12); and Devane et al UK Patent

15 Application 2 239 803.

16 Electrotransport devices having reusable controllers and which are

17 adapted to be used with multiple drug-containing units are particularly well

18 suited for drug administration to patients outside of clinic/doctor's office

19 settings (e.g., for those patients requiring long term medication).

20 Unfortunately, the existing schemes for ensuring that the drug reservoir

21 of an electrotransport device is connected to the electrode of the correct

22 polarity are not foolproof. This becomes an even greater problem in settings

23 outside of the clinic/doctor's office where the patient is expected to

24 periodically replace the drug-containing unit him/herself. The problem

25 becomes still greater in cases where the patient population tends to be

26 more elderly. DESCRIPTION OF THE INVENTION

It is an aspect of the present invention to ensure correct polarity electrical connection between the drug reservoir of a drug-containing assembly and the reusable controller of an electrotransport device comprised of a reusable controller adapted to be used with a plurality of drug-containing assemblies. The present invention is directed to ensuring correct polarity electrical connections in an electrotransport device comprised of a reusable electronic controller adapted to be used with a plurality of single use (e.g., disposable) drug-containing units. After the drug has been depleted from the drug- containing unit, the unit is disconnected from the controller and discarded, and then replaced with a fresh one. The controller includes a bipolar power source (e.g., one or more batteries), and optionally a circuit for controlling the timing, frequency, magnitude, etc. of the current applied by the device. The drug-containing unit has first and second electrodes, at least one of which contains the therapeutic agent (i.e., drug) to be delivered. In accordance with one embodiment of the present invention, the reusable controller is adapted to be electrically coupled to a more limited use (e.g., a single use) drug-containing unit by at least two electrically conductive snap connectors. The snap connectors have different sizes and/or are arranged with different male/female parts in the different respective units, so that the controller and the drug-containing unit may be coupled in only one way, i.e., with the correct polarity connections. In an alternative embodiment of the present invention, a projecting member is provided on either the controller or the drug-containing unit with a correspondingly shaped hole on the other unit. The positioning of the projecting member and the correspondingly shaped hole are such that the controller and the drug-containing unit may be coupled in only one way, i.e., with the correct polarity connections. 1 BRIEF DESCRIPTION OF THE DRAWINGS

2

3 In the figures, wherein like parts are given like reference numerals and

4 wherein;

5 Fig. 1 is a perspective view of an electrotransport device comprised of

6 a reusable controller and a separate drug-containing unit, in an uncoupled configuration, which controller and unit are couplable in accordance with this β invention;

9 Fig. 2 is a cross sectional view of the device shown in Fig. 1, showing ιo the controller and the drug-containing unit in a coupled configuration; ιι Fig. 3 is a perspective view of an electrotransport device comprised of

12 a reusable controller and a separate drug-containing unit, in an uncoupled

13 configuration, which controller and drug unit are couplable in accordance with

14 another embodiment of this invention; is Fig. 4 is a perspective view of an electrotransport device comprised of

16 a reusable controller and a separate drug-containing unit, in an uncoupled

17 configuration, which controller and drug unit are couplable in accordance with is yet another embodiment of this invention;

19 Fig. 5 is a perspective view of another electrotransport device with the

20 controller and the drug-containing unit in an uncoupled configuration,

21 the drug-containing unit adapted to slidably engage the controller;

22 Fig. 6 is a bottom view of the device shown in Fig. 5 with the controller

23 and the drug-containing unit in a coupled configuration;

24 Fig. 7 is a sectional view of the device shown in Figs. 5 and 6, taken

25 along line 7-7 shown in Fig. 6;

26 Fig. 8 is a perspective view of an electrotransport device comprised of

27 a reusable controller and a separate drug-containing unit, in an uncoupled

28 configuration, which controller and drug-containing unit are couplable in

29 accordance with another embodiment of this invention; Fig. 9 is a top view of a drug-containing unit in accordance with another embodiment of the present invention; Fig. 10 is a side view of the drug-containing unit shown in Fig. 9; Fig. 11 is a perspective view showing the coupling of a reusable controller to the drug-containing unit illustrated in Figs. 9 and 10; Fig. 12 is a top view of the coupled system shown in Fig. 11 ; Fig. 13 is a top view of a coupled electrotransport system in accordance with another embodiment of the present invention; Fig. 14 is a top view of the drug-containing unit shown in Fig. 13; Fig. 15 is a side view of the drug-containing unit shown in Fig. 14, with parts shown in section; Fig. 16 is a top view of another electrotransport system in accordance with the present invention; Fig. 17 is a top view of the drug-containing unit of the system shown in Fig. 16; and Fig. 18 is a perspective view showing the coupling of the reusable controller to the drug-containing unit of the system shown in Figs. 16 and 17.

MODES FOR CARRYING OUT THE INVENTION

Fig. 1 is a perspective view of electrotransport device 10 having a reusable electronic controller 12 which is adapted to be coupled to and uncoupled from, drug-containing unit 30. The controller 12 is reusable, i.e., it is adapted to be used with a plurality of drug units 30, e.g., a series of identical and/or similar drug units 30. On the other hand, drug unit 30 typically has a more limited life and is adapted to be discarded after use, i.e., when the drug contained therein has been delivered or has been depleted. 1 The controller 12 is comprised of a housing 14, typically formed of a

2 molded plastic material. With reference to Fig. 2, there is shown a sectional

3 view of the device 10 with the drug unit 30 coupled to the controller 12. The controller 12 includes a battery 20, e.g. a button cell battery, for

5 powering the circuit board 22. The circuit board 22 is formed in a e conventional manner, having conductive traces patterned for interconnecting

7 component(s) 24 thereon. Electrical component(s) 24 control the β magnitude, timing, frequency, waveform shape, etc., of the electric current

9 applied by device 10. Although not critical to the invention, controller 12 ιo includes a push button switch 18 which can be used to start operation of ιι device 10 and a liquid crystal display (LCD) 16 which can display system

12 information such as current level, dosing level, number of doses delivered,

13 elapsed time of current application, battery strength, etc.

1 The drug unit 30 is configured to be removably coupled to the is controller 12, with the top of drug unit 30 adjacent to and facing the bottom of

16 the controller 12. The top of drug unit 30 is provided with the male parts of

17 two snap type connectors, the male parts being posts 36 and 38 which s extend upwardly from drug unit 30. The bottom of housing 14 is provided with

19 receptacles 26 and 28 (shown in Fig. 2) which are electrically connected

20 to the outputs of the circuit on circuit board 22 by through-board connectors

21 23 and 25, respectively. Receptacle 26 is positioned and sized to receive

22 donor post 36 and receptacle 28 is positioned and sized to receive counter

23 post 38. Receptacles 26, 28 and posts 36, 38 are made from an electrically

2 conductive material (e.g., a metal such as silver, brass, stainless steel,

25 platinum, gold, nickel, beryllium, copper, etc. or a metal coated polymer,

26 e.g., ABS with a silver coating). The donor post 36 is electrically connected to

2 the donor electrode 31 , which in turn is electrically connected to the donor

28 reservoir 32 which typically contains a solution of the therapeutic agent

29 (e.g., a drug salt) to be delivered. The counter post 38 is electrically

30 connected to the counter electrode 33, which in turn is electrically connected to the counter reservoir 34 which typically contains a solution of a biocompatible electrolyte (e.g., buffered saline). The electrodes 31 and 33 are typically comprised of electrically conductive materials, most preferably a silver (e.g., silver foil or silver powder loaded polymer) anodic electrode and a silver chloride cathodic electrode. The reservoirs 32 and 34 typically include hydrogel matrices which hold the drug or electrolyte solutions and are adapted to be placed in contact with the body surface (e.g., skin) of a patient (not shown) when in use. The electrodes 31 ,33 and the reservoirs 32,34 are isolated from each other by foam member 35. The bottom (i.e., patient contacting) surface of foam member 35 is preferably coated with a skin contact adhesive. A release liner 39 covers the body contacting surfaces of the two reservoirs 32 and 34 and the adhesive coated surface of foam member 35 before the unit 30 is put in use. The release liner 39 is preferably a silicone coated polyester sheet. The release liner 39 is removed when the device 10 is applied to the skin of a patient (not shown). Thus, the donor post 36 and the receptacle 26 comprise a snap type connector which electrically connects an output of the circuit on circuit board 22 to the drug-containing donor electrode 32. Similarly, the counter post 38 and the receptacle 28 comprise a snap type connector which electrically connects an output of the circuit on circuit board 22 to the electrolyte containing counter electrode 34. In addition to providing the above described electrically connections, the two snap connectors also provide a separable (i.e., not permanent) mechanical connection of the drug unit 30 to the controller 12. The two outputs of the circuit on circuit board 22 have different polarities, i.e., one output is positive and is adapted to be connected to the anodic electrode in drug unit 30 whereas the other circuit output is negative and is adapted to be connected to the cathodic electrode in drug unit 30. It is important to ensure that the connections of the two electrodes in drug unit 30 are connected to the controller outputs of the correct polarity, since if the connections are reversed (i.e., if the positive circuit output is connected to the cathodic electrode and the negative circuit output is connected to the anodic electrode), little if any drug would be delivered by electrotransport. The present invention ensures correct polarity connections by making it substantially impossible to make incorrect (i.e., reversed) polarity connections between the controller 12 and the drug unit 30. As is clearly shown in Figs. 1 and 2, the diameter of post 36 is larger than the diameter of post 38. Similarly, the inside diameter of receptacle 26 is larger than the inside diameter or receptacle 28. Preferably, the inside diameter of receptacle 28 is smaller than the diameter of post 36 so that it is not possible to insert post 36 into receptacle 28. In accordance with this embodiment of the present invention, each of posts 36 and 38 has a different size. Those skilled in the art will appreciate that in addition to the size (i.e., diameter) of posts 36, 38 being made different, the shape (e.g., cross-sectional or other shape) of posts 36, 38 could be made sufficiently different to ensure only correct polarity connections between controller 12 and drug unit 30. An alternate means for ensuring correct polarity connections between a drug unit having donor and counter electrodes and a controller is illustrated in Fig. 3. Reusable controller 12' is adapted to be separably connected to one or more drug units 40. Drug unit 40 has a donor post 42 which performs a similar function as donor post 36 illustrated in Figs. 1 and 2. However, unlike drug unit 30, drug unit 40 has a receptacle 44 which is electrically connected to the counter electrode (not shown) in the drug unit 40. Receptacle 44 is adapted to engage a post (not shown) extending from the underside of controller 12'. Thus, drug unit 40 contains both a male part (i.e., post 42) of a first snap connector and a female part (i.e., receptacle 44) of a second snap connector. The two snap connectors provide both electrical and mechanical coupling of the drug unit 40 to controller 12'. By having a ι male connector and a female connector in each of the drug unit 40 and the

2 controller 12', the coupling of the controller 12' to the drug unit 40 can only be

3 accomplished in one way, i.e., with the correct polarity connections.

4 Referring now to Fig. 4, there is shown an electrotransport device

5 comprised of a reusable electronic controller 12" and a drug unit 50.

6 Unlike device 10 illustrated in Figs, and 2, the reusable controller 12" has a

7 third snap type receptacle adapted to receive a third post 56 on drug unit 50. ^β Thus, posts 52 and 54 perform substantially the same function as posts 36,

9 38 in device 10. The positioning of the third post 56, as well as the o positioning of the receptacle (not shown) for post 56 in the bottom of 1 controller 12", should not be equidistant from posts 52 and 54 assuming that 2 the posts and receptacle are all the same size and shape. By positioning 3 post 56 closer to post 54 than to post 52, there is only one way to connect the 4 drug unit 50 to the controller 12", i.e., with correct polarity connections. 5 An alternative way to ensure correct polarity connections between a 6 controller 62 and a drug unit 80 is illustrated in Figs 5 to 7. Electrotransport 7 device 60 is comprised of a reusable controller which is adapted to be s coupled to a plurality of same or similar drug units 80 in succession. 9 The body of the controller 62, shown in section in Fig. 7, is shown as a solid 0 cross section to simplify the drawing. Those skilled in the art will appreciate 1 that controller 62 contains an electrical power source and a current control 2 circuit similar to that illustrated in Fig.2. Controller 62 has two circuit outputs 3 68 and 70 which need to make electrical connection to electrode contacts 82 and 84, respectively in order to ensure correct polarity electrical 5 connection of electrodes 88 and 90 to controller 62. Controller 62 includes a 6 clasp 64. The drug unit 80 is adapted to be slid into the space between clasp 7 64 and the body of controller 62. A post 66 engages notch 86 in drug unit 80 8 when the drug unit 80 is slid into place and helps position drug unit 80 relative 9 to controller 62 so that circuit output 68 touches electrode contact 82 and 0 circuit output 70 contacts electrode contact 84. In addition to the siding engagement of drug unit 80 with controller 62, there is also provided a snap type connector which provides secure, but separable, mechanical connection of drug unit 80 to controller 62. The snap connector is comprised of a receptacle 72 in the body of controller 62 and a post 92 on drug unit 80. The post 92 snaps into receptacle 72 as best shown in Fig. 7. An alternative way to ensure correct polarity connections between a controller 1 12 and a drug unit 130 is illustrated in Fig. 8. Electrotransport device 1 10 is comprised of a reusable controller 1 12 which is adapted to be coupled to a plurality of same or similar drug units 130 in succession. Controller 1 12 contains an electrical power source and a current control circuit similar to controller 12 illustrated in Figs. 1 and 2. Controller 1 12 has two receptacles (not shown in Fig. 8) adapted to engage posts 136 and 138 in drug unit 130. Unlike the device illustrated in Figs. 1 and 2, posts 136 and 138 have the same size. In order to ensure that the posts 136 and 138 are snapped into the correct receptacles on the underside of controller 112, a projecting member 134 is provided on the surface of drug unit 130 which abuts against the underside of controller 112. As shown in Fig. 8, projecting member 134 has a square shape which engages a square shaped hole (not shown in Fig. 8) on the underside of controller 1 12. Those skilled in the art will appreciate that projecting member 134 may have any number of different shapes such as triangular, rectangular, circular, half-moon, etc. and should preferably project out a sufficient distance from the surface of drug unit 130 to ensure that post 138 cannot engage the incorrect receptacle in controller 1 12 in the event the patient attempts to couple the drug unit 130 to the controller with incorrect polarity connections. Preferably, the projecting member 134 is provided on a spine member 132 having increased rigidity. It is important that projecting member 134 be positioned on spine 132 at a location other than the midpoint between the two posts 136 and 138 in order to ensure that only one (i.e., the correct) polarity connection between the drug unit 130 and the controller 1 12 can be made. ι Referring now to Figs. 9 through 12, there is shown an alternate

2 embodiment of an electrotransport device 210 comprised of a controller 212

3 which is adapted to be coupled to a plurality of same or similar drug units 230

4 in succession. As best shown in Figs. 9 and 10, drug unit 230 has a pair of

5 posts 236, 238 adapted to engage receptacles (not shown) in the underside e of controller 212. The posts 236, 238 are preferably provided on a rigid spine member 232. Also provided on spine member 232 is a wedge-shaped β projecting member 234. As best shown in Figs. 11 and 12, the controller 212

9 has a wedge-shaped opening 235 with a size and shape which is adapted to ιo mate with the wedge-shaped projecting member 234. The projecting member ιι 234 and the opening 235 provide a visual lock and key mechanism which

12 visually guides the user to couple the controller 212 to the drug unit 230 with

13 the correct polarity connections therebetween. If further certainty is required,

14 the controller 212 may be made in a manner wherein the projecting member

15 234 engages and closes a switch contained in controller 212 thereby closing

16 a circuit pathway which enables the device to deliver electrotransport drive

17 current to the patient. When the projecting member 234 is disengaged from is the opening 235, the switch is opened and electrotransport drug delivery is

19 not possible.

20 Referring now to Figs. 13 through 15, there is shown an

21 electrotransport device 310 comprised of a reusable controller 312 adapted to

22 be coupled to a series of same or similar drug units 330. The drug unit 330

23 has a receptacle 334 which is adapted to accept and engage an end of

24 controller 312. The snap connections are provided in a position which insures

25 that the controller 312 can be electrically coupled to drug unit 330 only when

26 one of the two ends of controller 312 is inserted into receptacle 334.

27 Alternatively, the receptacle 334 can be sized and/or shaped to accept only

28 one of the two ends of controller 312. The selective engagement of controller

29 312 can be accomplished through any number of known means including

30 appropriately varying the size and/or shape of the respective ends of ι controller 312 and/or providing some type of appropriate keying mechanism

2 (not shown). In this way, only one end of the controller 312 may be engaged

3 within receptacle 334, thereby ensuring correct polarity connections between

4 the controller 312 and the drug unit 330 by means of the two snap connectors

5 of the kind described hereinbefore.

6 Referring now to Figs. 16 through 18, there is shown another

7 embodiment of the present invention. Like the system shown in Figures 13 β through 15, electrotransport device 410 is comprised of a controller 412 which

9 is adapted to fit in a single orientation within receptacle 434 on drug unit 430 ιo due to the dissimilarly shaped ends (one end is flat and the other end is ιι rounded) of controller 412 and receptacle 434. By shaping the receptacle

12 434 to "match" the shape of only one of the two ends of controller 412,

13 only one (i.e., the correct) polarity connection between controller 412 and the

14 drug unit 430 can be made.

15 While the foregoing detailed description has described several

16 embodiments for ensuring correct polarity coupling of an electrotransport

17 controller to a drug unit having donor and counter electrodes, it is to be

18 understood that the above description is illustrative only and not limiting of the

19 disclosed invention. It will be appreciated that it is possible for one skilled in

20 the art to modify the materials, dimensions, type and shape of the couplers

21 disclosed herein, or to include or exclude various elements, and yet remain

22 within the scope and spirit of this invention. Thus the invention is to be limited

23 only by the following claims.

Claims

ι Claims:

2

3 1. An electrotransport device (10) for delivering a therapeutic

4 agent through a body surface of a patient, the device (10) including an

5 assembly (30) having first and second electrodes (31 , 32 and 33, 34), at least

6 one of the electrodes containing the therapeutic agent to be delivered, and a

7 controller (12) having a bipolar electrical power source (20) for providing s electric current to the electrodes (31 , 32 and 33, 34), and coupling apparatus

9 (36, 26 and 38, 28) for electrically coupling and uncoupling the controller (12) o and the assembly (30), the device being characterized by a coupling 1 apparatus which permits the first electrode (31 , 32) to be electrically 2 connected to a predetermined pole of the bipolar power source (20) and 3 prevents the first electrode (31 , 32) from being electrically connected to the 4 other pole of the bipolar power source (20). 5 2. The device of claim 1 , wherein the coupling apparatus permits 6 the second electrode (33, 34) to be electrically connected to the other pole of 7 the bipolar power source (20) and prevents the second electrode (33, 34) s from being electrically connected to the predetermined pole of the bipolar 9 power source (20). 0 3. The device of claim 1 , wherein the predetermined pole of the 1 bipolar power source (20) is a positive pole, the electrode electrically 2 connected to the predetermined pole is an anode, and the therapeutic agent 3 is cationic. 4 4. The device of claim 1 , wherein the predetermined pole of the 5 bipolar power source (20) is a negative pole, the electrode electrically 6 connected to the predetermined pole is a cathode, and the therapeutic agent 7 is anionic. 8 5. The device of claim 1 , wherein the coupling apparatus 9 comprises a pair of electrically conductive snap connectors (36, 26 0 and 38, 28). 1 6. The device of claim 5, wherein the snap connectors (36, 26 and

2 38, 28) are comprised of a material selected from the group consisting of

3 metal and carbon.

4 7. The device of claim 6, wherein the metal is selected from the

5 group consisting of silver and stainless steel.

6 8. The device of claim 1 , wherein the coupling apparatus also

7 provides a mechanical coupling of the assembly (30) to the controller (12). β 9. The device of claim 1 , wherein the coupling apparatus

9 comprises a first coupler (36, 26) having male (36) and female (26) mating ιo members, the first electrode (31 , 32) being electrically connected to the power ιι source (20) when the first coupler mating members (32, 26) are mated, and a

12 second coupler (38, 28) having male (38) and female (28) mating members,

13 the second electrode (33, 34) being electrically connected to the power

14 source (20) when the second coupler mating members (38, 28) are mated, is and wherein the male mating member (36) of the first coupler is unable to

16 mate with the female mating member (28) of the second coupler.

17 10. The device of claim 1 , wherein the coupling apparatus

18 comprises a first coupler having first and second pairs (52, 54) of male and

19 female mating members, the first electrode (31, 32) being electrically

20 connected to the power source (20) when the two pairs (52, 54) of male and

21 female mating members are mated, and a second coupler having a third pair

22 (56) of male and female mating members, the second electrode being

23 electrically connected to the power source when the third pair of male and

24 female mating members are mated, and wherein the positioning of the three

25 pairs of male and female mating members permits only one electrical

26 connection of the assembly (50) and the controller (12").

2 11. The device of claim 10, wherein both of the first and second

28 pairs of mating members must be mated in order to electrically connect the

29 first electrode to the power source. ι 12. The device of claim 10, wherein only the first pair of mating

2 members must be mated in order to electrically connect the first electrode to

3 the power source, the second pair of mating members providing a mechanical

4 coupling of the assembly and the controller.

5 13. The device of claim 1 , wherein the coupling apparatus

6 comprises a first coupler (44) having male and female mating members, the

7 first electrode (31 , 32) being electrically connected to the power source (20) β when the first coupler (44) mating members are mated, and a second coupler

9 (42) having male and female mating members, the second electrode (33, 34) ιo being electrically connected to the power source (20) when the second ιι coupler (42) mating members are mated, and wherein the male mating

12 member of the first coupler is positioned on the controller (12') and the male

13 mating member (42) of the second coupler is positioned on the

14 assembly (40).

15 14. The device of claim 1 , wherein the coupling apparatus

16 comprises a first coupler having male and female mating members, the first

17 electrode being electrically connected to the power source when the first

18 coupler mating members are mated, and a second coupler having male and

19 female mating members, the second electrode being electrically connected to

20 the power source when the second coupler mating members are mated, and

21 wherein the female mating member of the first coupler is positioned on the

22 controller and the female mating member of the second coupler is positioned

23 on the assembly.

24 15. The device of claim 1 , wherein the coupling apparatus

25 comprises a first coupler having male and female mating members, the first

26 electrode being electrically connected to the power source when the first

27 coupler mating members are mated, and a second coupler having male and

28 female mating members, the second electrode being electrically connected to

29 the power source when the second coupler mating members are mated, ι the mating members being positioned to achieve an overhang/non-alignment

2 orientation of the controller with the assembly when the first coupler male

3 mating member is mated to the second coupler female mating member and

4 the first coupler female mating member is mated to the second coupler male

5 mating member.

6 16. The device of claim 1 , wherein the bipolar power source (20)

7 comprises a battery. β 17. The device of claim 1 , wherein the assembly (30) is adapted to

9 be discarded after a single use. o 18. The device of claim 1 , wherein the controller (12) is adapted to 1 be coupled to a plurality of assemblies (30) in succession. 2 19. A method of electrically coupling an assembly (30) to a 3 controller (12), the assembly (30) having first and second electrodes (31 , 21 4 and 33, 34) and at least one of the electrodes containing a therapeutic agent s to be delivered, the controller (12) having a bipolar electrical power source 6 (20) for providing electric current to the electrodes (31 , 32 and 33, 34), 7 the method comprising electrically coupling and uncoupling the controller (12) 8 and the assembly (30) by means of a coupling apparatus (36, 26 and 38, 28) 9 which permits the first electrode (31 , 32) to be electrically connected to a 0 predetermined pole of the bipolar power source (20) and prevents the first 1 electrode (31 , 32) from being electrically connected to the other pole of the 2 bipolar power source (20). 3 20. The. method of claim 19, wherein the coupling of the controller 4 (12) and the assembly (30) is achieved by means of an electrically conductive 5 snap connector (36, 26). 6 21. The method of claim 19, wherein the coupling of the controller (12) the assembly (30) is achieved by means of a pair of electrically 8 conductive snap connectors (36, 26 and 38, 28). 9 ι 22. The method of claim 19, wherein the bipolar power source (20)

2 comprises a battery.

3 23. The method of claim 19, including discarding the assembly (30)

4 after the assembly (30) is uncoupled from the controller (12).

5 24. The method of claim 19, including coupling the controller (12) to

6 a plurality of assemblies (30), one at a time in succession.

7 25. The device of claim 1 , wherein the coupling apparatus

8 comprises a projecting member on one of the controller (112) and the

9 assembly (130). ιo 26. The device of claim 25, wherein the projecting member engages ιι an opening on the other of the assembly (130) and the controller (112).

12 27. The device of claim 1 , wherein the coupling apparatus

13 comprises a receptacle (334, 434) on the assembly (330, 430) and wherein

1 the controller (312, 412) is adapted to engage the receptacle (334, 434) in

15 only a single orientation.