Smart-Pill Tracking in the Gut

Team Members: Saransh Sharma, Khalil B. Ramadi, Nikhil H. Poole, Shriya S. Srinivasan, Keiko Ishida, Johannes Kuosmanen, Josh Jenkins, Fatemeh Aghlmand, Margaret B. Swift, Mikhail G. Shapiro, Giovanni Traverso, Azita Emami

The advancement in medical technology has led to the development of innovative diagnostic and treatment methods for gastrointestinal (GI) disorders. A key area of focus in this field is the localization and tracking of ingestible smart pills, which are invaluable tools in the diagnosis and management of various GI conditions. In our latest project, we have made significant strides in this area by developing a sophisticated system for the wireless 3D tracking of smart pills within the GI tract. This system is designed to operate in real-time and offers millimeter-scale resolution, marking a significant improvement in tracking capabilities.

The core of our system lies in the generation of 3D magnetic field gradients within the GI field of view. This is accomplished using high-efficiency planar electromagnetic coils, which are ingeniously designed to encode each point in space with a unique magnetic field magnitude. This encoding ensures that every spatial location within the GI tract can be precisely identified based on its distinct magnetic field characteristics.

The smart pills, central to this system, are miniaturized marvels of engineering. They are equipped with low-power, wireless technology that enables them to measure the magnetic field magnitude in their immediate vicinity accurately. As these smart pills navigate through the complex environment of the GI tract, they continuously transmit data regarding the field magnitude they encounter. This transmission allows for the decoding of their exact location within the GI tract, providing real-time tracking as they progress through the digestive system.

The potential applications of this system are vast and impactful. It could play a crucial role in monitoring conditions such as constipation and incontinence, offering a quantitative assessment of GI transit time. Furthermore, the precision of this tracking system opens up new possibilities for targeted therapeutic interventions, allowing for more effective and minimally invasive procedures. The ability to accurately track the movement and location of smart pills within the GI tract not only enhances diagnostic capabilities but also allows for a more personalized approach to treatment.

Our project represents a significant breakthrough in the field of medical technology, particularly in the diagnosis and treatment of GI disorders. The development of a system for the real-time, 3D tracking of ingestible smart pills with millimeter-scale resolution has the potential to revolutionize the way GI disorders are diagnosed and managed. By providing precise and real-time data, this system offers new insights into GI function and pathology, paving the way for more effective, targeted, and minimally invasive treatment options.




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Wireless Surgical Navigation

Team Members: Saransh Sharma, Azita Emami

In our groundbreaking project, we have successfully developed a state-of-the-art radiation-free system specifically designed to enhance the accuracy and safety of various precision surgical procedures. This innovative system is engineered for high-precision alignment, navigation, and tracking of both sensors and surgical tools, offering a revolutionary alternative to traditional methods.

Central to our system is the generation of 3D magnetic field gradients within a designated field-of-view. This sophisticated technique ensures that each point in space is associated with a distinct magnetic field value, creating a detailed and dynamic map of the surgical area. We have meticulously designed and constructed highly miniaturized devices that are both wireless and battery-less. These advanced devices possess the capability to measure their local magnetic field accurately, thereby enabling them to detect and respond to the gradient field.

A key feature of our system is its dual-device setup. One device can be seamlessly attached to an implant within the patient’s body, while another device can be affixed to a surgical tool. This dual functionality allows both devices to simultaneously measure and relay information about the magnetic field at their respective locations to an external display receiver. This real-time communication ensures continuous and precise monitoring during surgery.

Our system has undergone extensive testing, demonstrating an exceptional level of localization accuracy, with measurements achieving less than 100μm in 3D. This level of precision is among the highest reported in the field and represents a significant leap forward in surgical navigation technology.

One of the most significant benefits of our system is its ability to replace the harmful ionizing X-ray radiation traditionally used in precision surgeries. By eliminating the need for X-ray radiation for tracking surgical tools and implants, our system not only enhances the safety of the procedures but also reduces the potential health risks to both patients and medical staff.

Our radiation-free system for surgical alignment, navigation, and tracking represents a transformative development in medical technology. Its unparalleled precision, coupled with its radiation-free nature, positions it as an invaluable tool in the realm of precision surgeries. This advancement not only promises to improve surgical outcomes but also sets a new standard in patient care, emphasizing safety, accuracy, and innovation.



Related Publications

  • S. Sharma et al., “Wireless 3D Surgical Navigation and Tracking System With 100μm Accuracy Using Magnetic-Field Gradient-Based Localization,” in IEEE Transactions on Medical Imaging, vol. 40, no. 8, pp. 2066-2079, Aug. 2021, doi: 10.1109/TMI.2021.3071120.
  • S. Sharma et al., “3D Surgical Alignment with 100µm Resolution Using Magnetic-Field Gradient-Based Localization,” 2020 IEEE International Solid-State Circuits Conference – (ISSCC), San Francisco, CA, USA, 2020, pp. 318-320, doi: 10.1109/ISSCC19947.2020.9063108.

3D CMOS Magnetic Sensor

Team Members: Saransh Sharma

The 3D CMOS Magnetic Sensor represents a significant advancement in the field of magnetic sensing, which is integral to a wide array of applications across various industries, including automotive, navigation, medical electronics, and consumer products. Traditional Hall sensors, though compatible with CMOS technology, often grapple with issues such as subpar sensitivity and high power consumption. Our newly developed 3D magnetic sensor addresses these challenges by combining high sensitivity with ultra-low power operation, all within the standard CMOS process.

This innovative sensor is constructed with three orthogonal metal coils that are densely packed to enhance responsiveness. These coils are designed to generate a voltage in the presence of AC magnetic fields through electromagnetic induction. The resultant voltage signal is then meticulously processed by sophisticated on-chip circuitry. This circuitry is meticulously engineered to perform several critical functions: low-noise amplification to boost signal strength, filtering to eliminate unwanted noise, accurate peak detection, and efficient digitization. Remarkably, all these operations are achieved with an impressively low power consumption of just 14.8µW, enabling the sensor to detect magnetic fields at µT-level sensitivity.

The versatility of the 3D CMOS Magnetic Sensor makes it suitable for a broad spectrum of applications, particularly in scenarios that necessitate AC field sensing. In the biomedical realm, this sensor is poised to revolutionize various procedures and treatments. Its precision and sensitivity make it ideal for tracking catheters and guidewires during intricate endovascular procedures, thereby enhancing safety and outcomes. Additionally, its application in minimally invasive surgeries can lead to more accurate interventions, while its use in targeted radiotherapy can help in delivering treatment more precisely to the affected areas. Furthermore, the sensor’s capabilities extend to serving as fiducial markers in preoperative planning, providing critical data to guide surgical strategies.

In summary, the 3D CMOS Magnetic Sensor represents a leap forward in magnetic sensing technology. Its exceptional sensitivity, coupled with ultra-low power consumption, sets a new standard in the field. The sensor’s potential impact on medical electronics, particularly in improving the accuracy and safety of various medical procedures, underscores its significance. As we continue to explore and refine its applications, the sensor is poised to become an indispensable tool in numerous fields, driving innovation and enhancing capabilities across industries.



Related Publications

  • S. Sharma, H. Melton, L. Edmonds, O. Addington, M. Shapiro and A. Emami, “A Monolithic 3D Magnetic Sensor in 65nm CMOS with <10μTrms Noise and 14.8μW Power,” 2023 IEEE Custom Integrated Circuits Conference (CICC), San Antonio, TX, USA, 2023, pp. 1-2, doi: 10.1109/CICC57935.2023.10121313.

CMOS Fluorescence Sensor

Team Members: Fatima Aghlmand, Saransh Sharma

The development of a novel “Cell-Silicon” system, which fuses silicon chip technology with live bacterial biosensors, presents groundbreaking possibilities in the realms of smart medicine and environmental monitoring. This integrated approach aims to harness the unique capabilities of both silicon-based and biological sensing elements, thereby opening the door to a host of innovative applications.

A critical aspect of such systems is the necessity for on-chip optical filtering, particularly within the wavelength range that aligns with fluorescent proteins. These proteins are commonly employed as signal reporters in bacterial biosensors due to their ability to produce easily detectable fluorescence. However, a significant challenge arises from the fact that the operational range of existing technologies often fails to effectively detect signals emitted by these fluorescent proteins.

Addressing this challenge, our work introduces a fully integrated fluorescence sensor fabricated using 65nm standard Complementary Metal-Oxide-Semiconductor (CMOS) technology. This sensor is a comprehensive solution, incorporating on-chip bandpass optical filters, photodiodes, and dedicated processing circuitry. The design and implementation of this sensor enable it to precisely measure the dynamic fluorescent signals as well as monitor the growth patterns of living Escherichia coli (E. coli) bacterial cells.

One of the most innovative aspects of this research is the utilization of optogenetic techniques. By employing these methods, we have successfully demonstrated a proof of concept for establishing bidirectional communication between living cells and the CMOS chip. This breakthrough indicates the potential for not only monitoring but also controlling biological processes in real-time through electronic interfaces.

The significance of this integrated “Cell-Silicon” system extends far beyond its immediate applications. It lays the groundwork for the development of advanced closed-loop therapeutic solutions, wherein real-time biological feedback can inform and adjust treatment protocols. This technology heralds a new era in personalized medicine, where treatments can be dynamically tailored based on the patient’s biological responses, potentially improving efficacy and reducing side effects. Additionally, in environmental monitoring, this system could provide real-time, on-site analysis of biological markers, offering rapid and accurate assessments of environmental health. The possibilities are vast, and this innovative fusion of biological and silicon-based sensing technologies represents a critical step forward in the intersection of biotechnology and electronics.


Related Publications:

  • F. Aghimand, C. Hu, S. Sharma, K. K. Pochana, R. M. Murray and A. Emami, “A 65nm CMOS Living-Cell Dynamic Fluorescence Sensor with 1.05fA Sensitivity at 600/700nm Wavelengths,” 2023 IEEE International Solid-State Circuits Conference (ISSCC), San Francisco, CA, USA, 2023, pp. 312-314, doi: 10.1109/ISSCC42615.2023.10067325.
  • F. Aghlmand, C. Y. Hu, S. Sharma, K. Pochana, R. M. Murray and A. Emami, “A 65-nm CMOS Fluorescence Sensor for Dynamic Monitoring of Living Cells“, in IEEE Journal of Solid-State Circuits, vol. 58, no. 11, pp. 3003-3019, Nov. 2023, doi: 10.1109/JSSC.2023.3308853.

Wearable Biosensor for Fatigue Monitoring

Team Members: Saransh Sharma

To effectively monitor the health and performance of military personnel under challenging conditions such as extreme weather, resource scarcity, unsanitary environments, and exposure to exotic diseases, we propose the development of an advanced wearable biosensor patch. This innovative device is designed to continuously track a comprehensive range of biomarkers directly from human sweat. It focuses on three primary categories: metabolic biomarkers, vital signs parameters, and immune response biomarkers.

The wearable biosensor leverages cutting-edge technology to analyze these biomarkers in real-time. By integrating machine learning algorithms, the device can accurately predict fatigue levels, providing a crucial and timely understanding of the physical state of military forces, sailors, and athletes. This predictive capability is pivotal in enhancing overall performance and plays a significant role in risk management and injury prevention strategies.

We are currently in the process of designing the sensor patch, which features a high-performance, low-power integrated circuit (IC) chip. This chip is equipped with functionalities critical for efficient biosensing, including multi-channel signal acquisition, advanced data processing capabilities like chopping, amplification, filtering, digitization, and seamless wireless data communication.

The next phase of our project involves rigorous testing and validation. We plan to conduct in vivo trials with human subjects to assess the biosensor’s accuracy, reliability, and practical applicability in real-world scenarios. Through these trials, we aim to fine-tune the device’s functionality and ensure it meets the high standards required for deployment in military and athletic settings. The ultimate goal is to create a reliable, non-invasive tool that offers real-time insights into the physiological condition of individuals operating in demanding environments, thereby contributing significantly to their health, safety, and performance optimization.



3D Nvigation for High-Precision Surgery

A 3D localization system using magnetic field gradients that can replace X-Ray fluoroscopy in high precision surgery has been developed by our team. Monotonically varying magnetic fields encode spatial points uniquely in the field-of-view and are sensed by miniaturized devices with wireless power and data telemetry. Relative device locations are displayed in real-time. A prototype system consisting of a 65nm CMOS chip and gradient coils achieves a localization error of <100µm in 3D when tested in-vitro.

Location-Broadcasting Chips

We present an alternative approach to microscale device localization based on concepts from nuclear magnetic resonance. In particular, the magnetic-field-dependent precession frequency of nuclear spins allows their location in space to be encoded through the application of magnetic field gradients. This allows MRI to visualize signals from nuclear spins located throughout a specimen with ~100 µm resolution.

Fully Implantable Glucose and Lactate Sensor

Miniaturization of implantable biosensors for continuous, in vivo monitoring of clinically relevant analytes is an important step toward viability of such devices. While wireless power delivery via on-chip antennas promises miniaturization and realization of minimally invasive devices, it can only support low levels of power consumption. This is due to the significant tissue absorption at high frequencies, small size of the chip and quality factor of on-chip inductors. Therefore, reducing the power consumption of the sensor while maintaining high sensitivity and dynamic range is crucial.

Circuits for Biological and Medical Systems

Retinal Prosthesis

Most progressive vision loss occurs when the first layer of the retina (the photoreceptors) is damaged. Retinal prostheses aim to restore vision by bypassing the damaged photoreceptors and directly stimulating the remaining healthy neurons. Our approach uses highly scaled technologies to reduce area and power, and to support hundreds of channels for fully intraocular implants.

Origami Biomedical Implants

Origami implant design is a 3D integration technique which addresses the size and cost constraints in biomedical implants. Large systems can be split into multiple chips and connected using 3D integration techniques to be folded compactly for implantation and unfolded inside the body. Electronics can be partitioned into functional blocks for mass-production and customs implants can be assembled from these relatively cheap modules.