Emerging Additive Manufacturing Methods for Wearable Sensors: Opportunities to Expand Access to Personalized Health Monitoring

Abstract

Persistent disparities exist in access to state-of-the-art healthcare disproportionately affecting underserved and vulnerable populations. Advances in wearable sensors enabled by additive manufacturing (AM) offer new opportunities to address such disparities and enhance equitable access advanced diagnostic technologies. Additive manufacturing provides a pathway to rapidly prototype bespoke, multifunctional wearable sensors thereby circumventing existing barriers to innovation for resource-limited settings imposed by the need for specialized facilities, technical expertise, and capital-intensive processes. This review examines recent progress in the additive manufacture of wearable platforms for physiological health monitoring. Supported by an initial overview of relevant techniques, representative examples of 3D printed wearable sensors highlight the potential for measuring clinically-relevant biophysical and biochemical signals of interest. The review concludes with a discussion of the promise and utility of additive manufacturing for wearable sensors, emphasizing opportunities for expanding access to vital healthcare technology and addressing critical health disparities.

Keywords: 3D printing; Additive manufacturing; healthcare devices; personalized medicine; wearable sensors.

Figure 1:

Schematic illustrations of the primary additive manufacturing techniques utilized for fabricating wearable devices: (A) fused deposition modeling (FDM) printer, (B) material jetting, (C) aerosol jet printing (AJP), and (D) vat photopolymerization.

Figure 2.

(A) 3D printed “earable” core body temperature device. Adapted with permission from Ref.^[133] Copyright 2017, American Chemical Society. (B) 3D printed wearable pressure sensor. Adapted with permission from Ref.^[137] Copyright 2019 WILEY-VCH Verlag GmbH & Co. KGaA. (C) 3D printed wearable tactile sensor. Adapted with permission from Ref.^[106] Copyright 2021 Wiley-VCH GmbH. (D) Representative image of a patient specific 3D printed wearable pulse oximeter. Adapted with permission from Ref.^[151] Copyright 2020 WILEY-VCHVerlag GmbH & Co. KGaA. (E) 3D printed self-powered pressure sensor. Adapted with permission from Ref.^[154] Copyright 2023 Elsevier B.V. (F) 3D printed wearable strain sensor for human/machine interfacing. Adapted with permission from Ref.^[162] Copyright 2023 Springer Nature.

Figure 3:

(A) 3D printed electrochemical ring (e-ring). Adapted with permission from Ref.^[130] Copyright 2021, American Chemical Society. (B) 3D printed wearable, multifunctional wound dressing. Adapted with permission from Ref.^[183] Copyright 2017 WILEY-VCH Verlag GmbH & Co. KGaA. (C) 3D printed wearable sweat lactate sensors. Adapted with permission from Ref.^[166] Copyright 2022 Elsevier B.V. (D) 3D printed epidermal microfluidic device for sweat analysis. Adapted with permission from Ref.^[119] Copyright 2023 American Association for the Advancement of Science.

Figure 4:

(A) 3D printed hollow microneedle arrays for the collection and analysis of interstitial fluid. Adapted with permission from Ref.^[187] Copyright 2023 Elsevier B.V. (B) 3D printed wearable electrochemical microneedle sensing patch for continuously monitoring apomorphine levels in interstitial fluid. Adapted with permission from Ref.^[186] Copyright 2021 Elsevier B.V. (C) Aptamer-functionalized microneedles for pharmacokinetic measurements in interstitial fluid. Adapted with permission from Ref.^[188] Copyright 2024 Elsevier B.V.

Figure 5:

(A) 3D printed wearable smart E-glasses. Adapted with permission from Ref.^[123] Copyright 2020, American Chemical Society. (B) 3D printed wearable biosymbiotic device for multi-site, long-distance, wireless, and battery-free measurement of physiological signals. Adapted with permission from Ref.^[190] Copyright 2021, American Association for the Advancement of Science. (C) 3D printed colorimetric UV sensors. Adapted with permission from Ref.^[191] Copyright 2023 WILEY-VCH Verlag GmbH & Co. KGaA. (D) A multi-material 3D printed device containing conductive parts. Adapted with permission from Ref.^[192] Copyright 2023 The Royal Society of Chemistry. (E) 3D printed soft, wearable braille display. Adapted with permission from Ref.^[193] Copyright 2023 Elsevier B.V. (F) Epifluidic elastic electronic skin (e³-skin) with multimodal physiochemical sensing, energy management, and machine learning capabilities. Adapted with permission from Ref.^[194] Copyright 2023 American Association for the Advancement of Science.