Endoscopic additive manufacturing of conductors and wireless implants

Abstract

A device for 3D printing at least one electromagnetic component of a wireless implant in-situ may include an insertable shaft having a proximal end and a distal end, the insertable shaft defining a lumen. The device may include a reservoir coupled to the proximal end of the insertable shaft, the reservoir containing a conductive media. The device may include a pump connected to the reservoir and configured to inject the conductive media along the lumen. The device may include an extrusion nozzle at the distal end of the insertable shaft defining an outlet in fluid communication with the lumen.

Description

ENDOSCOPIC ADDITIVE MANUFACTURING OF CONDUCTORS ANDWIREEESS IMPEANTSCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Patent Application No. 63 / 524,420, filed June 30, 2023, which is incorporated herein by reference in its entirety.BACKGROUND

[0002] Wireless implants functionalized with antennas for wireless communication with external devices are becoming increasingly appealing for various diagnostic, therapeutic, and monitoring applications. Implanting such devices into the human body often requires major incisions performed during surgery. Besides the highly invasive nature of these surgeries and associated recovery time both inside and outside the hospital, the risk of post-operative complications increases as well (e.g., bacterial infection, prolonged discomfort, and immobility).

[0003] In turn, wireless implants are currently limited in clinical applicability, despite their numerous advantages in sensing / stimulating signals right at their source. Theoretical limitations exist as to how small the antenna can be without significantly compromising its Radio- Frequency (RF) performance, particularly inside the lossy biological tissue environment.

[0004] Therefore, there is a need for a safer and more efficient means of implanting devices and their associated components within the human body.SUMMARY

[0005] According to one aspect, a 3D printing device is disclosed, the device configured to print at least one electromagnetic component of a wireless implant in-situ. The device includes an insertable shaft having a proximal end and a distal end. The insertable shaft defines a lumen. The device further includes a reservoir coupled to the proximal end of the insertable shaft, the reservoir containing a conductive media. The device further includes a pump connected to the reservoir and configured to inject the conductive media along the lumen. The device further includes an extrusion nozzle at the distal end of the insertable shaft defining an outlet in fluid communication with the lumen.

[0006] In some implementations, the device further includes an articulating end effector at the distal end of the insertable shaft, wherein the articulating end effector is controllable to move the distal end and the extrusion nozzle of the device in a radial direction.

[0007] In some implementations, the conductive media is a biocompatible material capable of being disposed within a human body.

[0008] In some implementations, the conductive media includes Poly-3, 4-Ethylene Di-Oxy Thiophene (PEDOT) Polystyrene Sulfonate (PSS) Poly-Ethylene Glycol Di- Acrylate (PEGDA) (PEDOT:PSS:PEGDA).

[0009] In some implementations, the conductive media includes copper.

[0010] In some implementations, the device is coupled to a surgical probe configured to enter a body through a small incision.

[0011] In some implementations, the device is capable of operation at a human body temperature.

[0012] In some implementations, the conductive media is capable of curing at a human body temperature or a room temperature.

[0013] In some implementations, an extruded component formed by the conductive media has a resolution of 250 micrometers.

[0014] In some implementations, the outlet of the extrusion nozzle has a diameter 250-500 micrometers.

[0015] In some implementations, the device is configured to print radiofrequency-enabled structures (e.g., antennas) intracorporeally.

[0016] In some implementations, the electromagnetic component of the implant that is printed by the device is an antenna.

[0017] In some implementations, the printed antenna communicates in a range of 1MHz - 3 GHz (e.g., 13.56MHz, or 403MHz, or 2.4GHz).

[0018] In some implementations, the conductive media includes between 15% and 50% PolyEthylene Glycol Di- Acrylate (PEGDA) by volume (e.g., 21% or 30% PEGDA v / v).

[0019] In some implementations, the conductive media exhibits a conductivity of between 1x104 - 3x104 S / m (e.g., 2x104).

[0020] In some implementations, the conductive media exhibits a curing time of less than 5 minutes (e.g., less than 2 minutes or less than 1 minute).

[0021] In some implementations, the conductive media includes a frequency of operation between 0.01 and 6 GHz (e.g., 0.1-5 GHz).

[0022] In some implementations, the conductive media is photocurable.

[0023] In some implementations, the device further includes a light source directed towards the ejected conductive media to cure the conductive media.

[0024] According to another aspect of the disclosure, a system is disclosed, the system including a device as described herein. The system further includes a surgical probe coupled to the device and a controller in electrical or wireless communication with the device. The controller includes a memory having preconfigured instructions for moving the extrusion nozzle and dispensing the conductive media, an actuator in electrical communication with the pump, and a user interface configured to display information about the device.

[0025] In some implementations, the system further includes an insertable probe configured to emit electromagnetic radiation towards the conductive media to cure the conductive media.

[0026] In some implementations, the emitted electromagnetic radiation is visible light or ultraviolet light.

[0027] According to another aspect of the disclosure a method of 3D printing electromagnetic components intracorporeally is disclosed. The method includes providing a device including an insertable shaft defining a lumen, an extrusion nozzle at a distal end of the insertable shaft, a reservoir containing conductive media, and a pump connected to the reservoir. The method further includes inserting the insertable shaft of the device through a keyhole surgery site. The method further includes placing the extrusion nozzle adjacent to a target area. The method further includes activating the pump to motivate the conductive media along the lumen and out of the extrusion nozzle. The method further includes moving the extrusion nozzle in a predefined pattern to dispense the conductive media in the predefined pattern such that an electromagnetic component is formed. The method further includes curing the conductive media in place.

[0028] In some implementations, curing the conductive media includes using an ultraviolet light disposed at the distal end of the device.

[0029] In some implementations, the electromagnetic component is an antenna.

[0030] In some implementations, the conductive media includes Poly-3, 4-Ethylene Di-Oxy Thiophene (PEDOT) Polystyrene Sulfonate (PSS) Poly-Ethylene Glycol Di- Acrylate (PEGDA).

[0031] In some implementations, the electromagnetic component forms a portion of a wireless implant.

[0032] In some implementations, the method further includes connecting the electromagnetic component to a wireless implant; and communicating with the electromagnetic component from an external wireless source.

[0033] Additional advantages will be set forth in part in the description which follows or may be learned by practice. The advantages will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive, as claimed.BRIEF DESCRIPTION OF THE DRAWINGS

[0034] FIG. 1 A shows a diagram of a 3D printing device, according to one implementation.

[0035] FIG. IB shows an example printed construct in-situ, according to one implementation.

[0036] FIG. 1C shows a diagram of a 3D printing device and the associated controller, according to one implementation.

[0037] FIG. 2A shows a schematic illustrating direct wire 3D printing via an example printing device and an SMA connector, according to one implementation.

[0038] FIG. 2B shows an experimental example of a patch antenna printed on a 1.27mm thick substrate.

[0039] FIG. 2C shows an experimental example of a 4.5mm thick transmission line printed on a 1.52 mm substrate.

[0040] FIG. 3 shows a graph of comparative performance analysis of varying concentrations of PEDOT:PSS using dipole antennas, according to one implementation.

[0041] FIG. 4A shows a graph of measurements of the transmission line (TL) reflection (|Sn|) and transmission coefficient for various conductive materials, according to one implementation.

[0042] FIG. 4B shows a graph of measurements of the transmission line (TL) reflection (|S21|) and transmission coefficient for various conductive materials, wherein the inset shows the fabricated TLs, according to one implementation.

[0043] FIG. 4C shows a graph of resulting conductivity for different conductive materials at various frequencies, according to one implementation.

[0044] FIG. 5 shows a graph of repeatability studies for three transmission line samples each 21% and 30% PEGDA biomaterial, according to one implementation.

[0045] FIG. 6 shows a graph of the effect of varying conductivity in simulation of the max realized gain of an implanted patch antenna and free-space half-wavelength dipole antennas.

[0046] FIG. 7 A shows a graph of the reflection coefficient (|Sn|) performance for copper and PEDOT:PSS:PEGDA dipole antenna at 2.4GHz operating in free space, according to one implementation.

[0047] FIG. 7B shows a graph of the E- and H-plane radiation patterns for copper and PEDOT:PSS:PEGDA dipole antenna at 2.4GHz operating in free space, according to one implementation.

[0048] FIG. 7C shows a graph of the change in |Sn| response across five samples of 30% PEGDA, according to one implementation.

[0049] FIGS. 8A-8F provide a comparison of RF performance of copper and PEDOT:PSS:PEGDA implanted patch antennas in tissue media. FIG. 8A shows a graph of reflection coefficient (|Sn|) of implanted patches.

[0050] FIG. 8B shows a graph of transmission coefficient (|S2i|) between the implanted patches and copper dipoles.

[0051] FIG. 8C shows a telemetry setup, according to one implementation.

[0052] FIG. 8D shows a graph of input impedance and Q factor.

[0053] FIG. 8E shows a graph of simulated normalized radiation patterns.

[0054] FIG. 8F shows a graph of the effect of implant depth on |S2i| performance.

[0055] Various objects, aspects, features, and advantages of the disclosure will become more apparent and better understood by referring to the detailed description taken in conjunction with the accompanying drawings, in which like reference characters identify corresponding elementsthroughout. In the drawings, like reference numbers generally indicate identical, functionally similar, and / or structurally similar elements.DETAILED DESCRIPTION

[0056] Described herein are methods, systems, and devices for in-situ printing of circuitry and electromagnetic components. A novel approach is disclosed for manufacturing wireless implants intracorporeally, meaning inside the body, using a robotic material delivery probe that enters the human body via a ‘keyhole’ surgical site. A 3D-printer attached to a robotic delivery probe may be used in some implementations. The robotic delivery probe can enter the body through a small incision to print dielectrics and conductors at physiological temperatures and at resolution as high as 250 pm. Implanted circuits can be significantly miniaturized, permitting smaller incisions and / or being able to be embedded inside the body by means of injection. The materials of the device and / or conductive ink / media are biocompatible to minimize toxic effects, cure inside the human body in a safe manner, have mechanical flexibility that makes them compliant with soft tissue, and exhibit in vivo biostability. Electronics can be directly injected through the same minor incision and sutured in place and connected with a larger circuit and antenna.

[0057] In-Situ 3D Printing of Wireless Medical Implants

[0058] Medical implants functionalized with wireless capabilities have a variety of beneficial applications. Lying inconspicuously inside the body and sensing physiological signals right at their origin on a round-the-clock basis, wireless implants can help to shift healthcare models from reactive to proactive. However, widespread adoption of wireless implants is limited by the invasive process of placing them into the body. Existing practices rely on major incisions performed during surgery to embed medical implants. In turn, implants are currently restricted to only those in need (e.g., pacemakers, cochlear implants, neurostimulators). Miniature devices that can be injected by means of a needle have been explored, but they are limited in terms of allowable tissue depth and overall functionality. Ingestible ‘smart pills’ are also available, but they are again limited in terms of applications and can only stay in the body for up to ~8 hours. The systems, methods, and devices of the present disclosure address the various issues concerning embedding wireless implants. For example, advances in electronics enable miniaturized sensing interfaces, but the wireless (antenna) interface may remain large (50 to 750 mm2) due to fundamental electromagnetics (EM) limits.

[0059] Example System and Application: A novel approach is disclosed for 3D-printing wireless implants in-situ using a robotic material delivery probe that enters the human body via a minor incision. For example, see the device of FIG. 1A. Existing systems for in-situ bio-printing are limited to directly printing tissues and organs into the defect sites. However, the present disclosure relates to bio-printing antennas, EM components, or other pertinent electronics. This approach uses a novel 3D-printer attached to a robotic delivery probe that can enter the body through a small incision to print both dielectrics and conductors, at body temperature, and at resolution as high as 250 pm. Since the vast majority of wireless implant communications are carried out in the 13.56 MHz, 403 MHz, and 2.4 GHz bands, the associated wavelength implies that this resolution is more than sufficient to print the pertinent antennas and EM components. Electronics can be directly injected through the same minor incision (given their miniature size), or can be replaced by equivalent EM components and 3D-printed (e.g., capacitors can be replaced by open-circuited transmission lines). Finally, batteries can be eliminated by relying on Radio-Frequency power harvesting, inductive coupling, and / or backscattering approaches. Overall, the proposed approach: (a) reduces trauma, (b) expands the applications of wireless implants, (c) is not limited by implantation depth or by implant size and operating frequency, (d) is safe for the patient as it takes place at body temperature, (e) enables personalization of the implant before and during the 3D-printing process so as to account for the patient’s anatomy and pathology, and (f) in the long run, offers the ability to “refresh” or tailor the implant via a similar small incision (to change its functionality, to correct failures, etc.).

[0060] Example Implementations and Alternatives: Standard EM components may be printed (e.g., transmission lines, patch antennas) using state-of-the-practice dielectrics and conductive inks. The EM performance of these components can be measured for evaluation and application. Measurements may be contrasted vs. simulations and “gold- standard” prototypes fabricated on a milling machine. In testing implementations, 3D-printing may be performed in free-space and upon tissue-emulating phantoms.

[0061] A variety of options exist for in-house inks in terms of dielectric properties, feasibility of 3D-printing, phase transitions (to occur at body temperature), viscosity, biocompatibility, and biodegradability. For example, biodegradable conductive nanoparticles (e.g., Zn, Mo, Mg, W) may be used which will ideally provide stable function within a period matched to timedependent biological processes and then dissolve, forming benign end products. Roomtemperature sintering serves as a simple procedure to improve conductivity. Various designs ofencapsulation layers (e.g., SiCh, SislSk, liquid crystal polymers) may be used as water and ion barriers to offer desired lifetime of sensors / antennas for continuous, high fidelity operation in biofluids.

[0062] In fabrication and performance assessment will refine the process and will identify opportunities for other considerations (e.g., materials; electronics integration; powering; reliability and failure concerns; EM safety; integration of information such as anatomical features, inflammation or tissue biomechanical properties before and during printing; transfer from lab to clinical settings; cost; printing rate; printer operator). Use of the systems, methods, and devices is not limited to terrestrial applications - use in zero gravity environments, such as space, is also possible.

[0063] Applications: The devices, systems, and methods described herein can expand the applications of wireless implants and the population receiving them, enabling more accurate diagnostics by ‘sensing’ physiological parameters at their source, and empowering proactive medicine via 24 / 7 monitoring. Though not limiting, the devices, systems, and methods disclosed herein can find applications in: cardiac electrophysiology (e.g., to detect arrhythmias that currently rely on invasive implantation of loop recorders, pacemakers, and defibrillators); lung surgery (e.g., to monitor air leakage from the chest that currently relies on tethered tubes connected to a catheter); esophageal pH monitoring (e.g., to diagnose / monitor gastroestophageal reflux that currently relies on invasive catheters); and chemical sensing (e.g., to monitor oxygenation, neurotransmitters, and other species that are currently monitored via cumbersome means or not at all). In addition to providing state of the art health monitoring for the society at large, the technology may readily expand to space (e.g., to treat medical conditions of astronauts while in long-duration space exploration scenarios).Example Device and System

[0064] FIG. 1 A shows a device 10, according to one example. The device 10 may be used for 3D printed as described in the present disclosure. For example, the device 10 may be used to print at least one electromagnetic component of a wireless implant in-situ (e.g., on an anatomical structure of a person or animal). In some implementations, the structure printed by the device includes a media extruded from a needle which cures to provide a tissue engineering construct, as shown in FIG. IB.

[0065] The device 10 includes an insertable shaft 12 having a proximal end 14 and a distal end 16. The insertable shaft 12 defines a lumen 18 extending along the insertable shaft 12. Theinsertable shaft 12 is configured to enter an anatomical structure or body (e.g., a human body) via a keyhole surgical site (e.g., a small incision) in the body wall.

[0066] The device 10 further includes a reservoir 20 coupled to the proximal end 14 of the insertable shaft 12. The reservoir 20 is in fluid communication with the lumen 18. The reservoir 20 contains a conductive media.

[0067] The device 10 further includes a pump 22 connected to the reservoir and configured to inject the conductive media along the lumen 18. The device further includes an extrusion nozzle 24 at the distal end 16 of the insertable shaft 12. The extrusion nozzle 24 defines an outlet 26 in fluid communication with the lumen 18.

[0068] The distal end 16 of the insertable shaft 12, including the extrusion nozzle 24, is an articulating end effector that is controllable to move relative to the insertable shaft 12. In some implementations, the end effector can move the extrusion nozzle 24 axially and / or radially relative to the insertable shaft 12 (e.g., via a remote actuator).

[0069] The outlet 26 of the extrusion nozzle 24 may have a diameter in the range of 100 to 700 micrometers. For example, the outlet may have a diameter in the range of 100-200, or 200-300, or 300-400, or 400-500, or 500-600, or 600-700, or 200-600, or 250-500 micrometers. In some implementations, the implant or electromagnetic device printed by the device 10 has a resolution of 100-700 micrometers (e.g., 200-300, or 300-400, or 400-500, or 500-600, or 600-700, or 200- 600, or 250, or 250, or 450, or 550, or 650 micrometers).

[0070] The device 10 may be configured to print radiofrequency-enabled structures (e.g., antennas) intracorporeally. For example, the structure printed may be an antenna. For example, the antenna may communicate at or in a range common to medical devices and implants (e.g., wherein the printed antenna communicates in a range of 1MHz - 3 GHz, such as at 13.56MHz, or 403MHz, or 2.4GHz).

[0071] The conductive media of the device 10 may generally be curable at body temperature or room temperature. The conductive media may include copper. The conductive media may exhibits a conductivity of between 1X104- 3X104S / m (e.g., 1-2; 1.5-2; 1-2.5; 1.5-3; 2-3; or 2.5-3 xlO4S / m).

[0072] The conductive media may have a curing time of less than a minute, less than 2 mintues, or less than 5 minutes. The curing of the conductive media may occur at or near room temperature or body temperature. The conductive media may be photocurable (e.g., via aseparate probe or via a light source on the device. The photo-curability may include visible or ultraviolet light.

[0073] The conductive media of the device 10 may comprise Poly-3, 4-Ethylene Di-Oxy Thiophene (PEDOT) Polystyrene Sulfonate (PSS) Poly-Ethylene Glycol Di- Acrylate (PEGDA) (PEDOT:PSS:PEGDA). For example, the conductive media may comprises between 15% and 50% Poly-Ethylene Glycol Di- Acrylate (PEGDA) by volume (e.g., 21% or 30% PEGDA v / v). Further details, implementations, and variations on the conductive media, and the PEDOT:PSS:PEGDA implementation of the conductive media, are found in the Experimental Testing and Results section.

[0074] Further disclosed herein is a system 100 including the device 10 as described and shown in FIG. 1 A. For example, FIG. 1C shows a system 100 including the device 10 and a computing device 900 including a controller 910. It should be understood that the example computing device 900 is only one example of a suitable computing environment upon which embodiments of the invention may be implemented. Optionally, the computing device 900 can be a well-known computing system including, but not limited to, personal computers, servers, handheld or laptop devices, multiprocessor systems, microprocessor-based systems, network personal computers (PCs), minicomputers, mainframe computers, embedded systems, and / or distributed computing environments including a plurality of any of the above systems or devices. Distributed computing environments enable remote computing devices, which are connected to a communication network or other data transmission medium, to perform various tasks. In the distributed computing environment, the program modules, applications, and other data may be stored on local and / or remote computer storage media.

[0075] In an embodiment, the computing device 900 may comprise two or more computers in communication with each other that collaborate to perform a task. For example, but not by way of limitation, an application may be partitioned in such a way as to permit concurrent and / or parallel processing of the instructions of the application. Alternatively, the data processed by the application may be partitioned in such a way as to permit concurrent and / or parallel processing of different portions of a data set by the two or more computers.

[0076] In its most basic configuration, computing device 900 and / or the controller 910 therein typically includes at least one processing unit 920 and system memory 930. Depending on the exact configuration and type of computing device, system memory 930 may be volatile (such as random access memory (RAM)), non-volatile (such as read-only memory (ROM), flashmemory, etc.), or some combination of the two. This most basic configuration is illustrated in FIG. 1C by a dashed line. The processing unit 920 may be a standard programmable processor that performs arithmetic and logic operations necessary for operation of the computing device 900. While only one processing unit 920 is shown, multiple processors may be present. Thus, while instructions may be discussed as executed by a processor, the instructions may be executed simultaneously, serially, or otherwise executed by one or multiple processors. The computing device 900 may also include a bus or other communication mechanism for communicating information among various components of the computing device 900.

[0077] Computing device 900 may have additional features / functionality. For example, computing device 900 may include additional storage such as removable storage 940 and nonremovable storage 950 including, but not limited to, magnetic or optical disks or tapes. Computing device 900 may also contain network connection(s) 980 that allow the device to communicate with other devices such as over the communication pathways described herein. Computing device 900 may also have input device(s) 970 such as a keyboards, keypads, switches, dials, mice, track balls, touch screens, voice recognizers, card readers, paper tape readers, or other well-known input devices. Output device(s) 960 such as a printers, video monitors, liquid crystal displays (LCDs), touch screen displays, displays, speakers, etc. may also be included. The additional devices may be connected to the bus in order to facilitate communication of data among the components of the computing device 900. All these devices are well known in the art and need not be discussed at length here.

[0078] The processing unit 920 may be configured to execute program code encoded in tangible, computer-readable media. Tangible, computer-readable media refers to any media that is capable of providing data that causes the computing device 900 (i.e., a machine) to operate in a particular fashion. Various computer-readable media may be utilized to provide instructions to the processing unit 920 for execution. Example tangible, computer-readable media may include, but is not limited to, volatile media, non-volatile media, removable media and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data. System memory 930, removable storage 940, and non-removable storage 950 are all examples of tangible, computer storage media. Example tangible, computer-readable recording media include, but are not limited to, an integrated circuit (e.g., field-programmable gate array or application-specific IC), a hard disk, an optical disk, a magneto-optical disk, a floppy disk, a magnetic tape, a holographicstorage medium, a solid-state device, RAM, ROM, electrically erasable program read-only memory (EEPROM), flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices.

[0079] In an example implementation, the processing unit 920 may execute program code stored in the system memory 930. For example, the bus may carry data to the system memory 930, from which the processing unit 920 receives and executes instructions. The data received by the system memory 930 may optionally be stored on the removable storage 940 or the nonremovable storage 950 before or after execution by the processing unit 920.Experimental Testing and Results

[0080] A study was conducted to demonstrate photocurable poly-3, 4-ethylene di-oxy thiophene (PEDOT):polystyrene sulfonate (PSS):poly-ethylene glycol di-acrylate (PEGDA) biomaterial as a promising candidate for 3-D-printing implantable antennas intracorporeally. Previous work has demonstrated the feasibility of a robotic probe to 3-D-print biological tissues via a minor incision. This same probe could also 3-D-print implantable antennas as long as a suitable conductive material is identified in terms of conductivity, printability, biocompatibility, and ability to cure at room / body temperature for safety purposes. The study assessed the frequency-dependent conductivity of this biomaterial and explored the radio frequency (RF) performance of resulting antennas operating in free space and inside tissue-emulating phantoms. Results show that PEDOT:PSS biomaterials with 21% and 30% PEGDA concentration exhibit a conductivity of — 104 S / m up to 5 GHz, suitable for wireless implants. Comparing the two, 21% PEGDA content exhibits poorer curing abilities, while 30% PEGDA exhibits slightly lower conductivity. Measurements for 2.4 GHz free-space dipoles conducted in an anechoic chamber reveal only ~0.8 and -1 dB lower gain for PEDOT:PSS:21% PEGDA and PEDOT:PSS:30% PEGDA biomaterial, respectively, as compared to their copper counterpart. For a 5 mm-deep implanted patch antenna, these two biomaterials exhibit 3.05 and 3.84 dB higher transmission loss than copper, respectively. If deemed necessary, this performance degradation can be overcome by increasing the overall antenna size since the printing process is now minimally invasive and miniaturization requirements can be relaxed.I. Introduction

[0081] Wireless implants functionalized with antennas are becoming increasingly appealing for various diagnostic, therapeutic, and monitoring applications such as pacemakers andcardioverter defibrillators, intra-cranial pressure monitors, neurosensors / stimulators, body temperature sensors, gastric stimulators, and blood glucose monitors, among others. Traditional surgeries to implant these devices are highly invasive, require prolonged recovery time, and often lead to postoperative complications. Though electronics can be miniaturized and potentially embedded inside the body by means of injection, there are fundamental electromagnetic limits as to how small the implantable antenna can be while still maintaining adequate radio frequency (RF) performance. For example, a volumetric antenna reduction by 65% results in a 19% reduction in maximum gain and 80% increase in the maximum 1 g- averaged specific absorption rate (SAR).

[0082] Minimally invasive, intracorporeal (meaning inside the body) 3-D printing of implantable antennas shows great promise. In intracorporeal 3-D printing, a small diameter (order of 8 mm) probe enters a keyhole surgery site and delivers (prints) material in a specific pattern. Multiple probes, or material exchanges, can be used to create multi-material antennas. Besides the safety benefits associated with this approach, a special advantage is that antenna miniaturization requirements can now be relaxed without altering the size of the incision. Some previous studies have printed an interstitial antenna using a coaxial applicator that heats a conductive polymer at 40° C and cures it in 10 s. However, the resulting conductivity was poor (9.09 S / m), while the need to apply heat inside the body is undesirable for safety reasons.

[0083] In a major step forward, this study discloses intracorporeal 3-D printing of implantable antennas using high-conductivity materials that are delivered and cured at room / body temperature. The disclosed approach utilizes a robotic delivery probe for 3-D-printing biological tissues intracorporeally. In some examples, the printing of lossy dielectrics has already been demonstrated, but suitable conductive inks have yet to be explored. Here, the term ‘suitable’ refers to inks that: 1) exhibit conductivity of at least 104 S / m as deemed necessary for maintaining adequate RF performance; 2) are curable at room / body temperature to ensure patient safety; 3) are biocompatible; and 4) can be mechanically delivered by the printer.Disclosed herein is poly-3, 4-ethylene di-oxy thiophene (PEDOT) polystyrene sulfonate (PSS) poly-ethylene glycol diacrylate (PEGDA), a polymer-based conductive biomaterial cured using a 365 nm ultraviolet (UV) light, as a promising candidate for the intracorporeal fabrication of antennas. The study reported measurements of conductivity up to 6 GHz, which covers some of the most important bands for wireless implants. The study also fabricated and assessed the RF performance of free-space dipole and implantable patch antennas at 2.4 GHz. A comparison withother conductive polymers used for biomedical applications in the literature (see Table 1) shows improved conductivity, curing, and safety (temperature and biocompatibility) performance for the proposed PEDOT:PSS:PEGDA biomaterial.Table 1: Comparison of Conductive Polymers

[0084] In this study, as one proof-of-concept, the study printed PEDOT:PSS:PEGDA on off- the-shelf dielectric substrates with 3-D printing being conducted outside the tissue environment. In one experiment, the objective was to obtain a comprehensive understanding of the PEDOT:PSS:PEGDA electromagnetic behavior, with a further goal of 3-D-printing fully functional antennas intracorporeally. With a focus on antenna applications, specifics related to material optimization were excluded from some portions of the study, and the focus was rather on assessing the RF conductivity performance of PEDOT:PSS:PEGDA (Section II) and its suitability for realizing antenna structures (Section III).

[0085] In summary, this study introduced a new fabrication method for implantable antennas, where a 3-D-printer would print the antenna intracorporeally via a small incision on the patient’sbody. The study showed the feasibility of such an approach: some previous examples utilized inks of 9.09 S / m in conductivity, whereas this study showed ~104 S / m. Since this is the first time that PEDOT:PSS:PEGDA is evaluated for implanted antenna applications, the study purposely selected simple / standard antenna structures (dipoles and patches) in Section III to prove the concept, with no goal of antenna design optimization. The results are, of course, applicable to multiple antenna design.II. RF Conductivity of PEDOT:PSS:PEGDA

[0086] Biomaterial Composition and Formulation - The conductive biomaterial used in this study is based on PEDOT:PSS biomaterial which is known to be biocompatible and can be modified by various additives to provide desired mechanical properties, good conductivity, and printability. Conductivity of the PEDOT:PSS solution (Heraeus Electronic Materials, Clevios # TM PH1000) is lower than 1 S / cm and ethylene glycol (EG) (Sigma Aldrich, # 324558) was used to increase its conductivity. To cure the biomaterial, the photocurable PEGDA 575 (Sigma Aldrich, # 437441-500ML) with Phenylbis (2, 4, 6-trimethylbenzoyl) phosphine oxide (BAPO) photo initiator (IMG Resins, # 162881-26-7) was used to cure the biomaterial at room temperature. The PEDOT:PSS concentration was selected based on adequate viscosity and printability as 3%-7% w / v PEDOT:PSS, 8% v / v EG, 21% or 30% v / v PEGDA, and 1% w / v PEGDA photo initiator.

[0087] The study examined two different PEGDA concentrations of 21% and 30% to evaluate the trade-off between conductivity and curing capabilities. To fabricate the biomaterial, the as received PEDOT:PSS was stirred for 6 h and filtered using a 450 pm syringe filter. The filtered solution was cryogenically frozen in liquid nitrogen and lyophilized for 72 h to eliminate the water content. To make 10 mL biomaterial with 30% PEGDA content, 350 mg of the lyophilized PEDOT:PSS was redispersed in a solution of 0.8 mL EG and 6.2 mL deionized water and mixed with a vortex mixer until no solid content was observed. In a separate tube, 3 mL of PEGDA was prepared and 33.6 mg BAPO photo-initiator was gradually added to the tube and mixed by vortex mixer. To make a homogenous ink, the liquid was thoroughly mixed with the vortex mixer and sonicated for 1 h before being grounded with a Disposable Tissue Grinder (Fisher Scientific, # 02-542-07). According to some examples, 2%-3% PEGDA would yield the highest conductivity for PEDOT:PSS films. However, other research recommended using 30% PEGDA content for fast curing capability and improved mechanical properties. This study investigated the RF performance of PEDOT:PSS biomaterial with 21% and 30% PEGDA content as bothshow good curing capabilities and adequate conductivity at direct current (DC) with the 21% ink having higher conductivity and lower curability conditions compared to the 30% one. The prepared biomaterial was manually loaded into a 1 mL glass syringe with a nozzle diameter of 514 pm and loaded into a directwrite printer. The ink was subsequently deposited on the printed circuit board (PCB) substrates with an SMA connector in either one end or two ends as to form the desired antenna or transmission line’s (TLs) shape as shown in FIGS. 2A-2C. The nozzle distance from surface was set to 400 pm and printing tracks were separated by 400 pm to print a 2-D coherent structure. The printed samples were cured by a 365 nm UV curing light (Thorlabs, # CS20K2,) with a 220 mW / cm2 light intensity at a distance of 2 mm from the sample with exposure time of 1 min / cm2 of the sample. The study focused on the RF performance of the PEDOT:PSS:PEGDA biomaterial and associated antennas.

[0088] Analyzing the Concentration-Dependent Behavior of PEDOT :PSS Biomaterial With Dipole Antennas - In order to evaluate the PEDOT:PSS biomaterial at RF frequencies, three different concentrations were examined using standard 2.4 GHz dipole antennas printed on a polysine glass slide. A surface-mount TL transformer from MiniCircuits (SCTX1-83-2W+) was used as a balun. The telemetry setup involved a copper dipole antenna as a reference transmitter, while dipoles with 5%, 6% and 7% PEDOT:PSS biomaterial served as receivers at 30 cm away. The reflection and transmission coefficients were measured using a network analyzer, as shown in FIG. 3. The reflection coefficients of 5%, 6% and 7% at 2.4 GHz were -3.92, -5.64, and -5.45 dB, respectively. The transmission coefficients were -24.40, -23.57, and -22.15 dB, respectively. That is, 7% PEDOT:PSS biomaterial performs better and is considered in the following investigations.

[0089] Conductivity Measurement Results - To determine the RF conductivity ofPEDOT:PSS:PEGDA biomaterial, the study pursued the transmission line (TL) approach. Specifically, the study: 1) fabricated two microstrip TLs of different lengths [3 and 5 cm, see inset of FIG. 4B]; 2) measured the return loss and insertion loss; 3) used the S-parameter deembedding technique to eliminate reflection losses at the input and output junctions; 4) removed dielectric and radiation losses by relying on copper-based counterparts of the TLs; and 5) derived the intrinsic conductivity of the printed material. All TLs were 4.5 mm-wide and fabricated on 1.52 mm-thick Rogers R03003 substrate (sr = 3, tanS = 0.01).

[0090] To realize the copper and PEDOT :PSS:PEGDA samples, the study used copper tape, 21% PEGDA bio-material, and 30% PEGDA biomaterial, respectively. Measurements of thereflection (|S11|) and transmission (|S21|) coefficient parameters for all six TLs (copper and two biomaterial concentrations, each of two different lengths) are shown in FIG. 4A. Measurements were taken using a Keysight PNA-L N5235A network analyzer in the 10 MHz-6 GHz range. As seen, the insertion loss of the 21% and 30% biomaterials at 1 GHz is 0.28 and 0.31 dB / cm respectively, which is only 0.26 and 0.29 dB / cm higher than copper. At 4 GHz, insertion loss increases to 0.81 and 1.08 dB / cm respectively, which is only 0.68 and 0.95 dB / cm higher than copper. These results confirm the promise of PEDOT:PSS:PEGDA as a highly conductive biomaterial. Indeed, conductivity results in FIG. 4B show that the average conductivity of both biomaterial concentrations is >104 S / m up to ~5 GHz which covers the bands of interest to implantable applications in Section I.

[0091] Repeatability Assessment - To assess repeatability, the study evaluated three distinct samples of TLs of each length and conducted five tests on each sample (FIG. 5); the center line represents the average of three samples and the shaded region represents the largest deviation about the mean. In summary, the average deviation about the mean for 21% PEGDA content was 0.326 and 0.854 dB for the 3 and 5 cm samples, respectively. For 30% PEGDA content, the average deviation was 0.316 and 0.727 dB for the 3 and 5 cm samples, respectively. These discrepancies are mostly attributed to the weak contact between the conductive biomaterial TL and the SMA connector. By printing directly on the metal pin of the SMA connector rather than establishing a connection afterward, this inaccuracy may be minimized. Another method is to use an adhesive such as silver glue to strengthen the contact surface and establish a more durable connection.III. RF Antenna Performance

[0092] The performance of free-space dipole and implantable patch antennas made of PEDOT:PSS with 21% and 30% PEGDA biomaterial is hereafter assessed. Per Section I, the study purposely select simple / standard antennas as the study is not aiming to optimize any particular design. Accordingly, the study is not aiming to overcome the reduced conductivity of PEDOT:PSS:PEGDA as compared to copper. If the study wants to have the ability to print intracorporeally, the study may have to sacrifice some properties. Approaches for overcoming low conductivity issues are well established.

[0093] Simulation of Conductivity Effects on Antenna Performance - Previous studies using reflection characteristics have indicated that a minimum conductivity of 104 S / m may be suitable for implantable antenna applications. Here, this study expanded upon that work todemonstrate gain results and particularly realized gain that takes mismatch into account to determine adequate conductivity. Simulations were performed using the finite element method in the CST Microwave Studio (MWS). As a proof of concept, the study investigated free-space half-wavelength dipole antennas at 403 MHz, 915 MHz, and 2.4 GHz and an implanted patch antenna at 2.4 GHz. The implant antenna setup considers the 11 x 18.5 mm patch placed 5 mm deep inside a rectangular frequency-dependent 2 / 3 muscle tissue phantom representing average tissue properties. A second-order Debye model was used in simulation with an eighth-order fitting scheme, having an error of 13.4% before interpolation. A frequency domain solver was used to obtain the results. The implanted antenna was directly designed inside a tissue environment and the free-space performance was not evaluated separately.

[0094] Simulated maximum realized gain results as a function of conductivity are shown in FIG. 6. As seen, the gain is fairly constant above o = 106 S / m, below which deterioration increases. For the case of 2.4 GHz implant patch antenna, at c = 106 S / m, the maximum 3-D realized gain is -11.4 dB; at c = 105 S / m, it reduces by only 0.6 dB; and at c = 104 S / m, it reduces by 2.6 dB. Similar results were obtained for the remaining antennas. Based on these findings, the study concludes that conductivities of >105 S / m are excellent, while conductivities of ~ 104 S / m are adequate to fabricate antennas.

[0095] Free-Space PEDOT:PSS:PEGDA Antenna Performance - To validate the conductivity findings of FIG. 4C, the study first tested a free-space half-wavelength dipole antenna operating at 2.4 GHz. For comparison purposes, the study fabricated two antenna samples, with 21% and 30% PEGDA, respectively. Both antennas were printed on a polysine glass slide. Reflection coefficient measurements were taken using a network analyzer, while radiation patterns were measured in the ElectroScience Laboratory anechoic chamber. The balun mentioned in Section II was used. The study also simulated these antennas in CST MWS using the conductivity values obtained in Section II. Finally, the study contrasted the resulting performance versus “gold- standard” copper.

[0096] Reflection coefficient results are summarized in FIG. 7A, while far-field radiation patterns in the E- and H-planes are shown in FIG. 7B. For the free space dipole antenna simulations, the complex impedance at the resonant frequency for copper is 47.13 + j2.02 Q. For PEDOT:PSS 21% and 30% PEGDA, it is 56.14-j3.49 Q and 66.17-j l l.27 Q, respectively. The quality (Q) factor obtained using simulation is 6.96, 6.69, and 6.49, respectively. Overall, the simulation and measurement results are in good agreement. Slight differences in performance ofPEDOT:PSS:PEGDA versus copper dipole antennas can be rectified by fine-tuning the length of the dipole legs. The smaller bandwidth observed with the PEDOT:PSS:PEGDA biomaterial as compared to copper is likely due to shrinkage in the biomaterial post-printing. In fact, the bandwidth of the 21% PEGDA biomaterial is smaller than the 30% PEGDA hinting to larger shrinkage. This shrinkage only occurs in air-based media and is not of relevance to the study’s intended intracorporeal printing application. Further research is required to fully understand this phenomenon.

[0097] FIG. 7C illustrates the impact of fabrication errors on the |S11| performance. These variations can be attributed to both material and fabrication inconsistencies. Nevertheless, all samples consistently demonstrate that the dipole resonates closely within the operational band. The maximum co-pol gain measured for the copper prototype was 1.86 dB (0.086 dB lower than the simulated value), while for 21% PEGDA and 30% PEGDA, it was 1.06 and 0.805 dB, respectively. The combined effect of poor contact between the antenna-feed mechanism and inadequate contact during its rotation in the anechoic chamber degrades the measured gain. The cross-pol components of both PEDOT:PSS: 21% and 30% PEGDA biomaterials were below -15 dB for all scan angles. The simulation results showed that the radiation efficiency for copper was 99.10%, while PEDOT:PSS with 21% PEGDA and 30% PEGDA exhibited lower radiation efficiencies of 84.76% and 81.57%, respectively.

[0098] Implantable PEDOT:PSS:PEGDA Antenna Performance - The study was expanded by considering the 2.4 GHz microstrip implantable patch antenna of Section III. Two prototypes were fabricated using PEDOT:PSS with 21% and 30% PEGDA content, respectively [see inset of FIG. 8A], They were inserted 5 mm deep inside an 80% lean / 20% fat ground beef phantom used to replicate the average human tissues. A telemetry setup was then implemented [see FIG. 8C] where each of the implanted patches were set to communicate with a 2.4 GHz copper-based half-wavelength dipole placed 5.5 cm away.

[0099] Reflection coefficient results for the patch antennas and transmission coefficient results for the system are shown in FIG. 8A and FIG. 8B respectively. The simulated complex impedance and Q factor for copper, PEDOT:PSS 21%, and 30% PEGDA are shown in FIG. 8D. For the copper-based antenna, the input impedance observed through simulation at 2.4 GHz is 28.91 + j 1.98 Q. For fabricated antennas with 21% and 30% PEGDA, the corresponding input impedances are 53.5 + j 18.23 Q and 36.67 +j32.85 Q, respectively. Furthermore, the Q factors at 2.4 GHz are 14.98 for copper, 2.93 for 21% PEGDA, and 1.12 for 30% PEGDA. As seen,both the 21% and 30% PEGDA implanted antennas resonate at 2.4 GHz with |S 11| being well below -10 dB. Transmission loss at 2.4 GHz with 21% PEGDA is 3.05 dB higher than the copper counterpart. With 30% PEGDA, it is 3.84 dB. The nonuniform pattern of |S 11| for the biomaterials is mainly due to inconsistencies in fabrication. Nevertheless, the minimum |S 11| consistently stays well below -10 dB. As a result, the power entering the antenna is well within acceptable limits, explaining the observed satisfactory agreement in the |S21| measurement.

[0100] A zoomed-in view of the patch antenna as depicted in the inset of FIG. 8 A reveals tiny fissures in the printed structure, as a consequence of microcracks after curing the sample. This can be eliminated by using smaller diameter nozzles and reducing the spacing between printing tracks for more compact printing, thus improving the antenna performance. Moreover, any frequency shifts induced by reduced conductivity can be mitigated through careful adjustment of the antenna’s geometry. Increasing the size of the ground plane can also lead to improvements in gain and reductions in the sidelobe levels. Simulated radiation patterns (normalized) are shown in FIG. 8E. Table 2 provides a detailed comparison of the RF performance between the implanted patch antenna using the PEDOT:PSS:PEGDA biomaterial and copper. It presents a comprehensive analysis of various parameters, highlighting the performance differences using lower conductivity biomaterial. The lower gain observed in the case of 21% PEGDA can be attributed to the conductivity values considered in CST, as obtained in Section II-C. Note that CST uses a fitting scheme with an error of 13.4% before interpolation. Measured results, however, indicate a better performance. To characterize the communication link, the implantable antenna depth was varied from 5 to 20 mm and the performance is compared in FIG. 8F. Other communication link parameters can be calculated based on previously reported approaches. SAR simulations were also conducted considering a 1010 kg / m3 tissue mass density. To comply with the Federal Communications Commission (FCC) guidelines of SARlg < 1.6 W / kg, the maximum input power was found to be 9.9, 14.1, and 11.7 dBm, for implanted patches based on copper, 21% PEGDA and 30% PEGDA, respectively.Table 2: Comparison of RF Parameters for Implanted Patch Antennas Made of Copper and PEDOT:PSS Biomaterial

[0101] Conclusion - This communication investigated the feasibility of PEDOT:PSS:PEGDA biomaterial in fabricating RF structures (TLs and antennas) using 3-D-printing with a robotic probe, with an emphasis on examining the impact of decreased conductivity on RF performance. The vision is for this approach to ultimately 3-D-print wireless implants intracorporeally via a minor incision on the patient’s body. The studies showed that the biomaterial containing 7% PEDOT:PSS demonstrates superior performance compared to those with 5% and 6% content. Meanwhile, compositions with 21% and 30% PEGDA exhibit a conductivity of approximately 104 S / m up to 5 GHz. Simulations confirmed these conductivity values to be appropriate for implantable antenna applications. Comparing the two, 21% PEGDA content exhibits poorer curing properties, while 30% PEGDA exhibits slightly lower conductivity. Compared to gold standard copper, PEDOT:PSS:21% PEGDA exhibited only 0.8 dB lower measured maximum 3- D gain in free space and 3.05 dB lower measured transmission coefficient for an implantable scenario. PEDOT:PSS:30% PEGDA exhibited 1 dB lower measured 3-D gain in free space and 3.84 dB lower measured transmission coefficient for an implantable scenario. To counter lower gain values, a standard technique to increase antenna footprint could be implemented: since the printing process is now minimally invasive, miniaturization requirements can be relaxed. Future research will focus on optimizing the biomaterial at RF frequencies, performing parametric studies on the effects of manufacturing defects on the antenna performance, and printing of both dielectrics and PEDOT:PSS:PEGDA inks inside biological tissue media for various diagnostic, therapeutic, and monitoring applications.Configuration of Certain Implementations

[0102] The construction and arrangement of the systems and methods as shown in the various implementations are illustrative only. Although only a few implementations have been described in detail in this disclosure, many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes, and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.). For example, the position of elements may be reversed or otherwise varied, and the nature or number of discrete elements or positions may be altered or varied. Accordingly, all such modifications are intended to be included within the scope of the present disclosure. The order or sequence of any process or method steps may be varied or re-sequenced according to alternative implementations. Other substitutions, modifications, changes, and omissions may be made in the design, operatingconditions, and arrangement of the implementations without departing from the scope of the present disclosure.

[0103] Although the figures show a specific order of method steps, the order of the steps may differ from what is depicted. Also, two or more steps may be performed concurrently or with partial concurrence. Such variation will depend on the software and hardware systems chosen and on designer choice. All such variations are within the scope of the disclosure. Likewise, software implementations could be accomplished with standard programming techniques with rule-based logic and other logic to accomplish the various connection steps, processing steps, comparison steps and decision steps.

[0104] It is to be understood that the methods and systems are not limited to specific synthetic methods, specific components, or to particular compositions. It is also to be understood that the terminology used herein is for the purpose of describing particular implementations only and is not intended to be limiting.

[0105] As used in the specification and the appended claims, the singular forms “a,” “an” and “the” include plural referents unless the context clearly dictates otherwise. Ranges may be expressed herein as from “about” one particular value, and / or to “about” another particular value. When such a range is expressed, another implementation includes from the one particular value and / or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent “about,” it will be understood that the particular value forms another implementation. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint.

[0106] “Optional” or “optionally” means that the subsequently described event or circumstance may or may not occur, and that the description includes instances where said event or circumstance occurs and instances where it does not.

[0107] Throughout the description and claims of this specification, the word “comprise” and variations of the word, such as “comprising” and “comprises,” means “including but not limited to,” and is not intended to exclude, for example, other additives, components, integers or steps. “Exemplary” means “an example of’ and is not intended to convey an indication of a preferred or ideal implementation. “Such as” is not used in a restrictive sense, but for explanatory purposes.

[0108] Disclosed are components that can be used to perform the disclosed methods and systems. These and other components are disclosed herein, and it is understood that when combinations, subsets, interactions, groups, etc. of these components are disclosed that while specific reference of each various individual and collective combinations and permutation of these may not be explicitly disclosed, each is specifically contemplated and described herein, for all methods and systems. This applies to all aspects of this application including, but not limited to, steps in disclosed methods. Thus, if there are a variety of additional steps that can be performed it is understood that each of these additional steps can be performed with any specific implementation or combination of implementations of the disclosed methods.

Claims

WHAT IS CLAIMED IS:

1. A 3D printing device configured to print at least one electromagnetic component of a wireless implant in-situ, the device comprising: an insertable shaft having a proximal end and a distal end, the insertable shaft defining a lumen; a reservoir coupled to the proximal end of the insertable shaft, the reservoir containing a conductive media; a pump connected to the reservoir and configured to inject the conductive media along the lumen; and an extrusion nozzle at the distal end of the insertable shaft defining an outlet in fluid communication with the lumen.

2. The device of claim 1, further comprising an articulating end effector at the distal end of the insertable shaft, wherein the articulating end effector is controllable to move the distal end and the extrusion nozzle of the device in a radial direction.

3. The device of any of claims 1-2, wherein the conductive media is a biocompatible material capable of being disposed within a human body.

4. The device of any of claims 1-3, wherein the conductive media comprises Poly-3, 4- Ethylene Di-Oxy Thiophene (PEDOT) Polystyrene Sulfonate (PSS) Poly-Ethylene Glycol Di- Acrylate (PEGDA) (PEDOT:PSS:PEGDA).

5. The device of any of claims 1-4, wherein the conductive media comprises copper.

6. The device of any of claims 1-5, wherein the device is coupled to a surgical probe configured to enter a body through a small incision.

7. The device of any of claims 1-6, wherein the device is capable of operation at a human body temperature.

8. The device of any of claims 1-7, the conductive media is capable of curing at a human body temperature or a room temperature.

9. The device of any of claims 1-8, wherein an extruded component formed by the conductive media has a resolution of 250 micrometers.

10. The device of any of claims 1-9, wherein the outlet of the extrusion nozzle has a diameter 250-500 micrometers.

11. The device of any of claims 1-10, wherein the device is configured to print radiofrequency-enabled structures (e.g., antennas) intracorporeally.

12. The device of any of claims 1-11, wherein the electromagnetic component of the implant that is printed by the device is an antenna.

13. The device of any of claims 1-12, wherein the printed antenna communicates in a range of 1MHz - 3 GHz (e.g., 13.56MHz, or 403MHz, or 2.4GHz).

14. The device of any of claims 1-13, wherein the conductive media comprises between 15% and 50% Poly-Ethylene Glycol Di- Acrylate (PEGDA) by volume (e.g., 21% or 30% PEGDA v / v).

15. The device of any of claims 1-14, wherein the conductive media exhibits a conductivity of between IxlO4- 3xl04S / m (e.g., 2xl04).

16. The device of any of claims 1-15, wherein the conductive media exhibits a curing time of less than 5 minutes (e.g., less than 2 minutes or less than 1 minute).

17. The device of any of claims 1-16, wherein the conductive media comprises a frequency of operation between 0.01 and 6 GHz (e.g., 0.1-5 GHz).

18. The device of any of claims 1-17, wherein the conductive media is photocurable.

19. The device of any of claims 1-18, further comprising a light source directed towards the ejected conductive media to cure the conductive media, ul20. A system comprising: the device of claim 1; a surgical probe coupled to the device; and a controller in electrical or wireless communication with the device, the controller comprising: a memory having preconfigured instructions for moving the extrusion nozzle and dispensing the conductive media; an actuator in electrical communication with the pump; and a user interface configured to display information about the device.

21. The system of claim 20, further comprising: an insertable probe configured to emit electromagnetic radiation towards the conductive media to cure the conductive media.

22. The system of any of claims 20-21, wherein the emitted electromagnetic radiation is visible light or ultraviolet light.

23. A method of 3D printing electromagnetic components intracorporeally, the method comprising: providing a device comprising an insertable shaft defining a lumen, an extrusion nozzle at a distal end of the insertable shaft, a reservoir containing conductive media, and a pump connected to the reservoir; inserting the insertable shaft of the device through a keyhole surgery site; placing the extrusion nozzle adjacent to a target area; activating the pump to motivate the conductive media along the lumen and out of the extrusion nozzle; moving the extrusion nozzle in a predefined pattern to dispense the conductive media in the predefined pattern such that an electromagnetic component is formed; and curing the conductive media in place.

24. The method of claim 23, wherein curing the conductive media comprises using an ultraviolet light disposed at the distal end of the device.

25. The method of any of claims 23-24, wherein the electromagnetic component is an antenna.

26. The method of any of claims 23-25, wherein the conductive media comprises Poly-3, 4- Ethylene Di-Oxy Thiophene (PEDOT) Polystyrene Sulfonate (PSS) Poly-Ethylene Glycol Di- Acrylate (PEGDA).

27. The method of any of claims 23-26, wherein the electromagnetic component forms a portion of a wireless implant.

28. The method of any of claims 23-27, further comprising: connecting the electromagnetic component to a wireless implant; and communicating with the electromagnetic component from an external wireless source.

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