Implantable Biosensors Research Articles

Transient Implantable Electronics for Postsurgery Preventive Medicine

AbstractThe field of postoperative care has seen a remarkable shift toward the utilization of electronic implantable devices, including sensors, biosensors, stimulators, and drug delivery systems, all designed with a biodegradable form factor and wireless data/power transmission capability. These technologies hold immense potential for postsurgery out‐of‐hospital monitoring during the postdischarged period, where continuous monitoring of physiological signals is lacking. Furthermore, these devices eliminate the need for secondary surgeries required for device retrieval as they can safely degraded in the body, thus enhancing patient recovery. This review delves into the latest advancements in biodegradable implantable devices, examining their application in monitoring vital signs, the innovative wireless communication and powering technologies they employ, and the biodegradable materials that enable their function. The analysis extends to evaluating the efficacy and limitations of these devices across various medical applications. Moreover, it explores future research directions, emphasizing material advancements, device miniaturization, customization, and the integration of artificial intelligence to create closed‐loop therapeutic systems. This comprehensive review underscores the transformative potential of these technologies in enhancing postoperative care and outlines the pathway for future innovations in this dynamic field.

Implantable Fluorogenic DNA Biosensor for Stress Detection.

Implantable sensors that can monitor analytes related to cognitive and physiological status have gained significant focus in recent years. We have developed an implantable biosensor to detect dehydroepiandrosterone sulfate (DHEA-S), a biomarker related to stress. The biosensor strategy was based on the principle of forced intercalation (FIT) aptamers designed to detect subtle intramolecular changes during aptamer-target binding events. By incorporating a steroid-specific fluorogenic aptamer into a hydrogel, the sensitivity and biostability of the FIT biosensor fiber were improved, which were essential for designing implantable sensors to monitor biomarker levels in the living body. The polyethylenimine-based hydrogel chosen for this study produced an optically transparent cross-linked network with optimal microstructure, physicochemical, and mechanical properties, making it suitable for optical biosensors. The in vitro studies showed that the biosensor fiber was successfully activated in human serum and skin analogue, providing a linear response to physiological concentrations of the steroid. We believe that this type of implantable platform can be effective in monitoring more complex biomarkers associated with physiological or psychological health.

Effects of Sterilization on Cellobiose Dehydrogenase and Glucose Oxidase Based Glucose Biosensors

AbstractResearch on implantable glucose biosensors is driven by the need for innovative medical devices for continuous glucose monitoring in patients with diabetes mellitus. However, biosensor sterilization is a step that is widely omitted during the process of innovation. To compare the effects of gamma irradiation and chemical treatment with ethylene oxide (carbon microarray electrodes are fabricated, functionalized with glucose oxidizing enzymes (cellobiose dehydrogenase CDH or glucose oxidase GOx), and coated with a specifically designed zwitterionic polymer prior to the sterilization step. Cyclic voltammetry in the presence of 100 mm glucose of the biosensors before and after sterilization shows that gamma irradiation with a low radiation rate (25 kGy, 260 Gy h−1) does not induce a sensor performance loss, unlike the EtO treatment. In addition, no cytotoxic by‐products are released after gamma sterilization. Based on these results obtained with both glucose oxidizing enzymes (CDH and GOx), gamma irradiation of the glucose biosensors with a low dose rate is preferable to exposure to EtO for biosensor terminal sterilization.

Highly Stable Flexible Organic Electrochemical Transistors with Natural Rubber Latex Additives.

Organic electrochemical transistors (OECTs) have attracted considerable interest in the context of wearable and implantable biosensors due to their remarkable signal amplification combined with seamless integration into biological systems. These properties underlie OECTs' potential utility across a range of bioelectronic applications. One of the main challenges to their practical applications is the mechanical limitation of PEDOT:PSS, the most typical conductive polymer used as a channel layer, when the OECTs are applied to implantable and stretchable bioelectronics. In this work, we address this critical issue by employing natural rubber latex (NRL) as an additive in PEDOT:PSS to improve flexibility and stretchability of the OECT channels. Although the inclusion of NRL leads to a decrease in transconductance, mainly due to a reduced carrier mobility from 0.3 to 0.1 cm2/V·s, the OECTs maintain satisfactory transconductance, exceeding 5 mS. Furthermore, it is demonstrated that the OECTs exhibit excellent mechanical stability while maintaining their performance even after 100 repetitive bending cycles. This work, therefore, suggests that the NRL/PEDOT:PSS composite film can be deployed for wearable/implantable applications, where high mechanical stability is needed. This finding opens up new avenues for practical use of OECTs in more robust and versatile wearable and implantable biosensors.

Implantable and Semi-Implantable Biosensors for Minimally Invasive Disease Diagnosis

Implantable and semi-implantable biosensors fabricated with biodegradable materials and nanomaterials have gained interest in the past few decades. Functionalized biodegradable materials and nanomaterials are usually employed to satisfy clinical and research requirements because of their advanced properties. Novel fabrication techniques were developed to improve the efficiency and accuracy. Different working mechanisms were facilitated to design different types of sensors. This review discusses the recent developments of implantable and semi-implantable biosensors. The materials and fabrications are browsed, and different types of biomedical sensors for different variables are discussed as a focused topic. The biomedical sensors are discussed according to the targets and working mechanisms, followed by a focus on the nervous system sensing to provide an inspiration that different variables can be studied simultaneously on the single system. In the end, challenges and prospects will be discussed. This review aims to provide information of materials, fabrication approaches, mechanisms, and the state of the art for inspiration in designing novel implantable and semi-implantable biomedical sensors for general diagnostic activities.

The significance of personalized medicine in healthcare services of the 21st century: a brief literature review

In modern healthcare services, patient safety is a primary goal. With technological advancements, the complexity of healthcare services increases, which in turn creates increased pressure on health professionals during decision-making processes and can lead to errors worldwide. Communication gaps, human factors, patient-originated issues, technical failures, and inadequate policies have been identified as the main causes of medical errors. While research shows that errors stem from human nature and are inevitable, it is emphasized that it is possible to develop methods that enhance patient safety. Utilizing digital technologies to improve the quality and efficiency of healthcare services is a crucial strategy. Innovations such as wearable technologies, mobile devices, digital media-delivered education and consulting services, telehealth applications, 3D printers, clinical decision support systems, and implantable biosensors encompass advancements in the digital health field. This research aims to analyze the complex and dynamic structure of healthcare services in the 21st century, especially considering the opportunities presented by the integration of artificial intelligence and genomic data, within the scope of the relevant literature.

P-696 Continuous monitoring of female hormones as a tool to improve IVF treatment’s efficacy

Abstract Study question Is it possible to employ an unobtrusive and injectable biosensor for real-time remote monitoring of patient’s hormone levels (LH, P4, E2) during an ART cycle? Summary answer In-situ implantable biosensors can effectively monitor clinically relevant hormone levels in real-time to improve ART cycle. What is known already Worldwide 48.5 million couples suffer from infertility. Hormonal imbalances can impede pregnancy by compromising the intricate processes of the reproductive system, affecting ovulation, egg quality, fallopian tube function, and endometrial receptivity. In the UK, assisted reproductive treatments (ART) have surged ten-fold in the last 20 years. ART success tremendously depends on the accurate measurement of hormone levels, namely Luteinizing Hormone (LH), oestradiol (E2), and progesterone (P4). These hormone levels change and pulsate during each patient cycle, requiring women to undergo a blood draw and endocrinology analysis every 2-3 days, making ART treatment a highly invasive and time consuming method. Study design, size, duration In order to determine the feasibility of the study question, Impli designed a minimally invasive implantable biosensor to continuously monitor essential hormones for women’s fertility such as LH, P4 and E2 in order to enhance the quality of treatment and improve the ART experience. An implantable electrochemical aptamer-based biosensors has been developed using cutting-edge electronics and electrochemical technologies. This minimally invasive biosensor allows patients to monitor their hormone levels in real-time during ART without venipuncture. Participants/materials, setting, methods The implantable biosensor contains the biorecognition interface, designed using the DNA-based aptamers coupled to the detection gold working electrodes. When the biosensor is in touch with the sample, hormones bind to the respective aptamers, which leads to changes in the electrical properties of the gold electrode. The changes are then monitored and calibrated through sensitive electrochemical techniques such as differential pulse voltammetry (DPV), using CHI potentiostat. Main results and the role of chance The biosensor was tested in vitro in artificial interstitial fluid (ISF) containing the range of 1 pg/ml to 1 µg/ml of hormones yielding a limit of detection (LOD) of 0.46 pg/ml, 1.15 pg/ml, and 0.58 pg/ml for E2, P4 and LH, respectively. Our data was validated using ELISA assays. A notably high linear correlation coefficient (R2) of approximately 0.9 was observed between the signals obtained from the ELISA and the biosensors, confirming the reliability of the aptamer biosensors for hormone analysis. The stability of the biosensor was also investigated over one week. The DPV technique was employed to assess the cross-reactivity of potential interferences with each biosensor. The results revealed that each biosensor exhibited notable selectivity towards its respective analyte over other interferences, at significantly higher concentrations. The biosensor was also characterised by microscopy techniques such as SEM and Raman analysis. Limitations, reasons for caution This novel implantable biosensor technology requires further upcoming validation in animal models to assess its ability for widespread use. Once validated, the appropriate human clinical trials will be undertaken. Wider implications of the findings The development and implementation of an unobtrusive implantable remote and continuous monitoring system, capturing hormone concentrations that are vital for success in an ART procedure, could transform the industry and positively influence patient’s access to care and the patient journey. Trial registration number No clinical trial

Aerosol jet 3D printing of gold micropillars and their behavior under compressive loads

Three-dimensional (3D) gold microarchitectures such as micropillars, microwires, and microlattices are used in applications such as implantable biosensors, microelectronic circuits, and catalytic devices. Additive Manufacturing (AM) is being explored to create such structures as lithography is more suitable to fabricate 2D or planar architectures. In this work, we use Aerosol Jet (AJ) nanoprinting, a jetting-based AM technique, to demonstrate fabrication of gold micropillars via stacking of nanoparticles and sintering them at temperatures ranging from 300°C to 900°C. We first demonstrate that AJ printed 2D planar films and 3D micropillars exhibit a different grain size distribution, even if they are printed and sintered under identical conditions. This unusual observation indicates that specific AM technique and structures are important in determining their grain structure, which affects their mechanical behavior. The AJ printed 3D gold micropillars are fabricated with aspect ratios up to 10:1 and sintered from lower to higher temperatures, to yield porosities ranging from 15 % to 2 %, and average grain sizes from 25 nm to 1.7 µm, respectively. Micropillars sintered at lower temperatures exhibit a brittle behavior with higher yield strength despite having a higher porosity but with smaller grain sizes, and vice versa. These results indicate that the 3D geometry of AJ printed architectures dictates the grain size evolution, and hence the mechanical properties. Further, the grain size dominates over porosity in determining the micropillar deformation. These results provide important design guidelines for 3D printed microarchitected structures fabricated via jetting-based AM techniques.

Nanofiber enhanced carbon cloth based flexible Miniaturized electrodes for Real-Time and specific insulin detection in blood serum

The development of sensitive and specific biosensors for real-time insulin monitoring is crucial for advancing diabetes management and improving patient outcomes. This study reports the fabrication of flexible electrodes based on titanium dioxide (TiO2) nanofiber-enhanced carbon cloth (CC) for the real-time, selective picomolar range of detection of insulin in blood serum. TiO2 nanofibers significantly increase the electrodes surface area and electron transfer capabilities, enhancing sensitivity and enabling rapid response times essential for real-time monitoring. The flexibility and mechanical stability of the carbon cloth substrate make it ideal for wearable and implantable biosensors, addressing limitations of conventional sensors, such as inadequate sensitivity, delayed response times, rigidity, and non-specific binding. The enhanced properties of the TiO2 nanofiber-modified carbon cloth composite facilitate the detection of low insulin concentrations, essential for early diagnosis and continuous monitoring in diabetes care. The robust TiO2 nanofibers and durable carbon cloth ensure sustained performance in complex biological environments. Chronoamperometry (CA) and cyclic voltammetry (CV) techniques are used to examine the electrocatalytic activity of the fabricated sensor, assessing parameters like pH, electrode resistance, concentration, and scan rate. While fasting, the normal range of insulin ranges from 12 to 150 pM. This sensor detects insulin in the 7 pM to 1000 pM range, with a detection limit of 2.7 pM and a quantification limit of 8.7 pM. Portability is validated using a handheld smartphone-based potentiostat. This developed miniaturized sensor provides a selective, interference-mitigated response for insulin detection in human serum, demonstrating significant advancements in flexible electrochemical sensor technology with crucial implications for diabetes care.

Exploring role of microbatteries in enhancing sustainability and functionality of implantable biosensors and bioelectronics

Microbatteries are emerging as a sustainable, miniaturized power source, crucial for implantable biomedical devices. Their significance lies in offering high energy density, longevity, and rechargeability, facilitating uninterrupted health monitoring and treatment within the body. The review delves into the development of microbatteries, emphasizing their miniaturization and biocompatibility, crucial for long-term, safe in-vivo use. It examines cutting-edge manufacturing techniques like physical and chemical vapor deposition, and atomic layer deposition, essential for the precision manufacture of the microbatteries. The paper contrasts primary and secondary batteries, highlighting the advantages of zinc-ion and magnesium-ion batteries for enhanced stability and reduced reactivity. It also explores biodegradable batteries, potentially obviating the need for surgical extraction post-use. The integration of microbatteries into diagnostic and therapeutic devices is also discussed, illustrating how they enhance the efficacy and sustainability of implantable biosensors and bioelectronics.

Bio-inspired and biomimetic composites based on biodegradable polymers for sensing applications with emphasis on early diagnosis of cancer

With the increasing demand for tissue adhesive, soft self-healing, antifouling, biodegradable and biocompatible biosensors, the use of biomimetic polymers has paved the way for the development of these advanced sensing systems. Especially, biomimetic polymers have provided new opportunities and development directions for the soft implantable and wearable biosensors. In fact, the impressive development in the bio-inspired and biomimetic composites based on biodegradable polymers has led to the creation of tissue-adhesive implantable biosensors with the minimal immune response or biofouling. This review aims to cover the advances in the mimetic biodegradable polymers (natural or synthetic) with an emphasis on the state-of-the-art sensing devices based on these composites. It also highlights the unique properties of biomimetic polymers such as self-healing, self-adhesion, enzyme-like activity, antibacterial activity, regenerative activity, etc. Considering the high rate of cancer in the world, especially in developing countries, a separate section is dedicated to the use of mimetic biopolymers-based sensors for early diagnosis of cancer. Finally, an outlook on the current challenges and future developments of this field is presented.

Stochastic Electrochemical Measurement of a Biofouling Layer on Gold.

Adsorption of a biofouling layer on the surface of biosensors decreases the electrochemical activity and hence shortens the service life of biosensors, particularly implantable and wearable biosensors. Real-time quantification of the loss of activity is important for in situ assessment of performance while presenting an opportunity to compensate for the loss of activity and recalibrate the sensor to extend the service life. Here, we introduce an electrochemical noise measurement technique as a tool for the quantification of the formation of a biofouling layer on the surface of gold. The technique uniquely affords thermodynamic and kinetic information without applying an external bias (potential and/or current), hence allowing the system to be appraised in its innate state. The technique relies on the analysis of non-faradaic current and potential fluctuations that are intrinsically generated by the interaction of charged species at the electrode surface, i.e., gold. An analytical model is extended to explain the significance of parameters drawn from statistical analysis of the noise signal. This concept is then examined in buffered media in the presence of albumin, a common protein in the blood and a known source of a fouling layer in biological systems. Results indicate that the statistical analysis of the noise signal can quantify the loss of electrochemical activity, which is also corroborated by impedance spectroscopy as a complementary technique.

Recent advances in implantable sensors and electronics using printable materials for advanced healthcare

This review article focuses on the recent printing technological progress in healthcare, underscoring the significant potential of implantable devices across diverse applications. Printing technologies have widespread use in developing health monitoring devices, diagnostic systems, and surgical devices. Recent years have witnessed remarkable progress in fabricating low-profile implantable devices, driven by advancements in printing technologies and nanomaterials. The importance of implantable biosensors and bioelectronics is highlighted, specifically exploring printing tools using bio-printable inks for practical applications, including a detailed examination of fabrication processes and essential parameters. This review also justifies the need for mechanical and electrical compatibility between bioelectronics and biological tissues. In addition to technological aspects, this article delves into the importance of appropriate packaging methods to enhance implantable devices' performance, compatibility, and longevity, which are made possible by integrating cutting-edge printing technology. Collectively, we aim to shed light on the holistic landscape of implantable biosensors and bioelectronics, showcasing their evolving role in advancing healthcare through innovative printing technologies.

Recent Progress and Challenges of Implantable Biodegradable Biosensors.

Implantable biosensors have evolved to the cutting-edge technology of personalized health care and provide promise for future directions in precision medicine. This is the reason why these devices stand to revolutionize our approach to health and disease management and offer insights into our bodily functions in ways that have never been possible before. This review article tries to delve into the important developments, new materials, and multifarious applications of these biosensors, along with a frank discussion on the challenges that the devices will face in their clinical deployment. In addition, techniques that have been employed for the improvement of the sensitivity and specificity of the biosensors alike are focused on in this article, like new biomarkers and advanced computational and data communicational models. A significant challenge of miniaturized in situ implants is that they need to be removed after serving their purpose. Surgical expulsion provokes discomfort to patients, potentially leading to post-operative complications. Therefore, the biodegradability of implants is an alternative method for removal through natural biological processes. This includes biocompatible materials to develop sensors that remain in the body over longer periods with a much-reduced immune response and better device longevity. However, the biodegradability of implantable sensors is still in its infancy compared to conventional non-biodegradable ones. Sensor design, morphology, fabrication, power, electronics, and data transmission all play a pivotal role in developing medically approved implantable biodegradable biosensors. Advanced material science and nanotechnology extended the capacity of different research groups to implement novel courses of action to design implantable and biodegradable sensor components. But the actualization of such potential for the transformative nature of the health sector, in the first place, will have to surmount the challenges related to biofouling, managing power, guaranteeing data security, and meeting today's rules and regulations. Solving these problems will, therefore, not only enhance the performance and reliability of implantable biodegradable biosensors but also facilitate the translation of laboratory development into clinics, serving patients worldwide in their better disease management and personalized therapeutic interventions.

Insertable Biosensors: Combining Implanted Sensing Materials with Wearable Monitors.

Insertable biosensor systems are medical diagnostic devices with two primary components: an implantable biosensor within the body and a wearable monitor that can remotely interrogate the biosensor from outside the body. Because the biosensor does not require a physical connection to the electronic monitor, insertable biosensor systems promise improved patient comfort, reduced inflammation and infection risk, and extended operational lifetimes relative to established percutaneous biosensor systems. However, the lack of physical connection also presents technical challenges that have necessitated new innovations in developing sensing chemistries, transduction methods, and communication modalities. In this review, we discuss the key developments that have made insertables a promising option for longitudinal biometric monitoring and highlight the essential needs and existing development challenges to realizing the next generation of insertables for extended-use diagnostic and prognostic devices.

Detection of Blood Clots Using a Whole Stent as an Active Implantable Biosensor.

Many cardiovascular problems stem from blockages that form within the vasculature and often treatment includes fitting a stent through percutaneous coronary intervention. This offers a minimally invasive therapy but re-occlusion through restenosis or thrombosis formation often occurs post-deployment. Research is ongoing into the creation of smart stents that can detect the occurrence of further problems. In this study, it is shown that selectively metalizing a non-conductive stent can create a set of electrodes that are capable of detecting a build-up of material around the stent. The associated increase in electrical impedance across the electrodes is measured, testing the stent with blood clot to mimic thrombosis. It is shown that the device is capable of sensing different amounts of occlusion. The stent can reproducibly sense the presence of clot showing a 16% +/-3% increase in impedance which is sufficient to reliably detect the clot when surrounded by explanted aorta (one sample t-test, p = 0.009, n = 9). It is demonstrated that this approach can be extended beyond the 3D printed prototypes by showing that it can be applied to a commercially available stent and it is believed that it can be further utilized by other types of medical implants.

Covalently grafted human serum albumin coating mitigates the foreign body response against silicone implants in mice

Implantable biomaterials and biosensors are integral components of modern medical systems but often encounter hindrances due to the foreign body response (FBR). Herein, we report an albumin coating strategy aimed at addressing this challenge. Using a facile and scalable silane coupling strategy, human serum albumin (HSA) is covalently grafted to the surface of polydimethylsiloxane (PDMS) implants. This covalently grafted albumin coating remains stable and resistant to displacement by other proteins. Notably, the PDMS with covalently grafted HSA strongly resists the fibrotic capsule formation following a 180-day subcutaneous implantation in C57BL/6 mice. Furthermore, the albumin coating led to reduced recruitment of macrophages and triggered a mild immune activation pattern. Exploration of albumin coatings sourced from various mammalian species has shown that only HSA exhibited a promising anti-FBR effect. The albumin coating method reported here holds the potential to improve and extend the function of silicone-based implants by mitigating the host responses to subcutaneously implanted biomaterials.

Approaches of wearable and implantable biosensor towards of developing in precision medicine.

In the relentless pursuit of precision medicine, the intersection of cutting-edge technology and healthcare has given rise to a transformative era. At the forefront of this revolution stands the burgeoning field of wearable and implantable biosensors, promising a paradigm shift in how we monitor, analyze, and tailor medical interventions. As these miniature marvels seamlessly integrate with the human body, they weave a tapestry of real-time health data, offering unprecedented insights into individual physiological landscapes. This log embarks on a journey into the realm of wearable and implantable biosensors, where the convergence of biology and technology heralds a new dawn in personalized healthcare. Here, we explore the intricate web of innovations, challenges, and the immense potential these bioelectronics sentinels hold in sculpting the future of precision medicine.

Wearable and implantable biosensors: mechanisms and applications in closed-loop therapeutic systems.

This review article examines the current state of wearable and implantable biosensors, offering an overview of their biosensing mechanisms and applications. We also delve into integrating these biosensors with therapeutic systems, discussing their operational principles and incorporation into closed-loop devices. Biosensing strategies are broadly categorized into chemical sensing for biomarker detection, physical sensing for monitoring physiological conditions such as pressure and temperature, and electrophysiological sensing for capturing bioelectrical activities. The discussion extends to recent developments in drug delivery and electrical stimulation devices to highlight their significant role in closed-loop therapy. By integrating with therapeutic devices, biosensors enable the modulation of treatment regimens based on real-time physiological data. This capability enhances the patient-specificity of medical interventions, an essential aspect of personalized healthcare. Recent innovations in integrating biosensors and therapeutic devices have led to the introduction of closed-loop wearable and implantable systems capable of achieving previously unattainable therapeutic outcomes. These technologies represent a significant leap towards dynamic, adaptive therapies that respond in real-time to patients' physiological states, offering a level of accuracy and effectiveness that is particularly beneficial for managing chronic conditions. This review also addresses the challenges associated with biosensor technologies. We also explore the prospects of these technologies to address their potential to transform disease management with more targeted and personalized treatment solutions.

Implementation of Glucose-6-Phosphate Dehydrogenase (G6PD) testing for Plasmodium vivax case management, a mixed method study from Cambodia.

Plasmodium vivax remains a challenge for malaria elimination since it forms dormant liver stages (hypnozoites) that can reactivate after initial infection. 8-aminoquinolone drugs kill hypnozoites but can cause severe hemolysis in individuals with Glucose-6-Phosphate Dehydrogenase (G6PD) deficiency. The STANDARD G6PD test (Biosensor) is a novel point-of-care diagnostic capable of identifying G6PD deficiency prior to treatment. In 2021, Cambodia implemented the Biosensor to facilitate radical cure treatment for vivax malaria. To assess the Biosensor's implementation after its national rollout, a mixed-methods study was conducted in eight districts across three provinces in Cambodia. Interviews, focus group discussions, and observations explored stakeholders' experiences with G6PD testing and factors influencing its implementation. Quantitative data illustrative of test implementation were gathered from routine surveillance forms and key proportions derived. Qualitative data were analyzed thematically. The main challenge to implementing G6PD testing was that only 49.2% (437/888) of eligible patients reached health centers for G6PD testing following malaria diagnosis by community health workers. Factors influencing this included road conditions and long distances to the health center, compounded by the cost of seeking further care and patients' perceptions of vivax malaria and its treatment. 93.9% (790/841) of eligible vivax malaria patients who successfully completed referral (429/434) and directly presented to the health center (360/407) were G6PD tested. Key enabling factors included the test's acceptability among health workers and their understanding of the rationale for testing. Only 36.5% (443/1213) of eligible vivax episodes appropriately received primaquine. 70.5% (165/234) of female patients and all children under 20 kilograms never received primaquine. Our findings suggest that access to radical cure requires robust infrastructure and income security, which would likely improve referral rates to health centers enabling access. Bringing treatment closer to patients, through community health workers and nuanced community engagement, would improve access to curative treatment of vivax malaria.