Biology subjects

Langer, R.

Publications and source records attributed to Langer, R..

At least 19 recordsLinked to original sources

bioRxiv2026

Accelerated discovery of thermostable vaccines using data-efficient AI

The inherent instability of mRNA- lipid nanoparticles (LNPs) necessitates ultra-cold storage, creating significant barriers for global distribution and limiting their broader application in advanced delivery systems. Solid-state, water-free formulations offer a promising solution by enhancing thermostability and enabling integration into emerging delivery modalities such as microneedle (MN) patches. Prior efforts to stabilize mRNA-LNPs have been constrained by narrow formulation scope and low-throughput screening methods. Here, we introduce AGENT (Algorithm-Guided Experimental design for lipid Nanoparticle Thermostabilization), an AI-driven framework that couples high-throughput experimentation with Bayesian optimization to rapidly identify thermostable mRNA-LNP formulations. Manual exploration of the formulation space required months of screening and yielded suboptimal candidates. In contrast, AGENT extracted maximal information from sparse experimental datasets, enabling efficient formulation optimization in only six iterations completed within one month. Using AGENT, we stabilized mRNA vaccines with diverse LNPs, including those in clinical use, into solid state formulations that retained 100% bioactivity after storage at 37 degree C for over two months. The thermostable vaccines induced antigen-specific IgG and germinal center B cell responses that were non-inferior to those elicited by freshly prepared soluble vaccines. The solid-state formulations were further incorporated into dissolvable MN patches and administered to rodents and nonhuman primates, yielding comparable neutralizing antibody titers compared to conventional intramuscular delivery of fresh vaccines. To our knowledge, this study presents the first demonstration of AI-driven design of thermostable RNA vaccines, offering a scalable, cold-chain-free solution for global immunization. By addressing both stability and delivery challenges, AGENT provides a potentially transformative platform for developing accessible next-generation therapeutics.

bioengineering↗

bioRxiv2026

Kinetics of Hypoglycemia in Diabetes Patients Informs Development of New Modes of Glucagon Therapy

Insulin therapy revolutionized the care of patients with diabetes starting [~]100 years ago, yet insulin-induced hypoglycemia remains a serious life-threatening complication of insulin therapy. Glucagon is a highly effective treatment; however current dosage forms remain under-utilized due to poor patient compliance. The development of improved and situation-specific glucagon therapies remains challenging due to the poor drug stability and incomplete knowledge of the kinetics of different hypoglycemic events. Thus, we analyzed continuous glucose monitor (CGM) data from 1135 patients with type 1 diabetes (T1D) representing 246.18 patient years. We show that a surprisingly large proportion of hypoglycemic episodes (20-30%) are follow-on events resulting from under-treatment of prior events, and that the average duration of independent hypoglycemic events can last up to 79 to 108 minutes. We further show that the kinetics of hypoglycemic onset and persistence varies significantly by patient history, severity, time of occurrence. Guided by these findings, we recognize the opportunity to develop high-density, readily-soluble, and thermostable (ReST) solid glucagon formulations, and painless application-specific microneedle-patches that are in line with the timing needs of T1D patients who are awake and asleep. Thus, we demonstrate (1) on-demand patches for rapid prevention or treatment of mild hypoglycemia during the day, and (2) enzyme-driven hypoglycemia-responsive patches supporting autonomous glucagon release during the night. We show excellent in vitro glucagon stability, loading, and release kinetics of both systems and demonstrate their ability to treat hypoglycemia in diabetic animals. The engineering of these delivery systems demonstrates the potential of human CGM data and solid glucagon formulations to enable new modes of glucagon therapy, thereby expanding the clinical role of glucagon beyond the emergency setting.

bioengineering↗

bioRxiv2026

Expansion Revealing of Pathology Resolves Nanostructures Associated with Inflammatory Phenotypes in COVID-19 Decedent Human Brain Tissue

Expansion revealing (ExR) elucidates cellular organization by separating proteins within dense nanostructures by 20x linear expansion, but requires fixation procedures incompatible with human pathology specimens. Here, we report ExR of pathology (ExRPath), which attains [~]20 nm resolution and decrowding of such tissues, through iterative 20x expansion, adapted to human brain pathology specimens. We also report a single-shot 15x expansion protocol for such tissues (15ExMPath), achieved through one-shot 15x expansion. Applying ExRPath and 15ExMPath to COVID-19-decedent brain tissue reveals periodic amyloid nanoclusters that co-localize with SARS-CoV-2 in a rare minority of patient specimens, pointing to a potential neuroinflammatory phenotype associated with COVID-19, and highlighting the power of high-throughput nanoimaging, empowered by expansion microscopy, for discovering potential novel disease mechanisms.

neuroscience↗

bioRxiv2025

Inflammatory reprogramming of human brain endothelial cells compromises blood-brain barrier integrity in Alzheimer's disease

Blood-brain barrier (BBB) dysfunction is an early feature of Alzheimers disease (AD), yet the endothelial gene-regulatory programs involved remain incompletely understood. We integrate postmortem human single-nucleus transcriptomics with iPSC-based BBB models to define a conserved, inflammation-driven pathway that compromises barrier integrity. We identify an NF-{kappa}B-associated endothelial gene module endoM2 that is elevated in AD, inversely correlated with cognition, and enriched for inflammation and endothelial-to-mesenchymal transition signatures. Cytokine stimulation of iPSC-derived brain endothelial cells induces morphological remodeling, lipid accumulation, junctional disruption, and transcriptomic shifts that mirror endoM2. A targeted drug screen identifies the NF-{kappa}B inhibitor BAY11-7082 as protective against cytokine-induced changes. In our perfusable iPSC-derived BBB-Chip that recapitulates human BBB signatures, single-cell profiling reveals inflammatory endothelial state-specific programs reflecting those in AD brains and demonstrates that BAY11-7082 suppresses cytokine-triggered dysfunction and reverses inflammation-associated gene activation. Together, these findings position cerebrovascular inflammation as a therapeutic target to preserve BBB integrity in AD.

neuroscience↗

bioRxiv2025

Vascular-Perfusable Human 3D Brain-on-Chip

Development and delivery of treatments for neurological diseases are limited by the tight and selective human blood-brain barrier (BBB). Although animal models have been important research and preclinical tools, the rodent BBB exhibits species differences and fails to capture the complexity of human genetics. Microphysiological systems incorporating human-derived cells hold great potential for modeling disease and therapeutic development, with advantages in screening throughput, real-time monitoring, and tunable genetic backgrounds when combined with induced pluripotent stem cell (iPSC) technology. Existing 3D BBB-on-chip systems have incorporated iPSC-derived endothelial cells but not the other major brain cell types from iPSCs, each of which contributes to brain physiology and disease. Here we developed a 3D Brain-Chip system incorporating endothelial cells, pericytes, astrocytes, neurons, microglia, and oligodendroglia from iPSCs. To enable this multicellular 3D co-culture in-chip, we designed a GelChip microfluidic platform using a 3D printing-based approach and dextran-based engineered hydrogel. Leveraging this platform, we co-cultured and characterized iPSC-derived brain-on-chips and modeled the brain microvasculature of APOE4, the strongest known genetic risk factor for sporadic Alzheimers disease. These 3D brain-on-chips provide a versatile system to assess BBB vascular morphology and function, investigate downstream neurological effects in disease, and screen therapeutics to optimize delivery to the brain. Significance StatementThe blood-brain barrier (BBB) is both a contributing factor to neurological disease and a major obstacle to its treatment, yet human-relevant models remain limited. Most existing brain-on-chip systems incorporate only subsets of BBB cell types and cannot capture the full cellular complexity of the human neurovascular unit. Here, we establish a vascular-perfusable 3D Brain-Chip using human induced pluripotent stem cell-derived brain cells including endothelial cells, pericytes, astrocytes, neurons, microglia, and oligodendroglia. This system enables systematic analysis of human genetic risk factors, such as APOE4 in Alzheimers disease, and provides a powerful platform to investigate BBB function and dysfunction and accelerate the development of more effective neurological therapies.

neuroscience↗

bioRxiv2025

Monolithic Shape-Shifting Absorbable Implants for Long-Term Contraception

Reversible contraceptives empower women to prevent unintended pregnancies and enable family planning. However, the need for frequent dosing with pills or injections often leads to suboptimal medication adherence and reduced effectiveness-an issue common to many chronic conditions. Long-acting drug delivery implants offer a compelling alternative by enabling autonomous, multi-year drug release, thereby improving real-world adherence and treatment outcomes. However, user acceptability and access are limited by need for invasive insertion and surgical end-of-life removal, particularly in low-resource settings, as well as by limited drug loading and suboptimal drug utilization efficiency, which constrain both the duration of therapy and the range of drugs that can be effectively delivered. To address these limitations, we developed the Monolithic Shape-shifting Absorbable Implants for Chronic Care (MoSAIC) platform-a minimally invasive, fully bioresorbable system that integrates compacted drug formulations with a space-efficient device architecture. This approach reduces implant size, eliminates the need for surgical removal, and prolongs therapeutic duration compared to existing implants. We develop compacted formulations of the contraceptive drug levonorgestrel (LNG), and other poorly water-solubility drugs, demonstrating exceptional drug loading (100% w/w) and multi-year sustained drug release via surface-mediated dissolution in rats. When incorporated into MoSAIC devices, these formulations enable high-efficiency drug loading and zero-order drug release kinetics with geometrically tunable rates and durations. As a result, MoSAIC systems can be designed to be smaller, less invasive, and/or longer lasting than current contraceptive implants such as Jadelle(R) and Nexplanon(R). The MoSAIC platform expands access to reversible contraception and supports long-term medication adherence, with the potential to improve health outcomes and quality of life. More broadly, it provides a flexible approach for delivering other potent, low-solubility therapeutics and lays the foundation for a "dose it and forget it" paradigm in chronic disease management, where adherence is designed into the therapy itself.

bioengineering↗

bioRxiv2024

Engineered Whole Lungs for Tissue Biology

End-stage lung disease and lung cancer significantly contribute to global mortality, necessitating new research strategies for studying pulmonary biology. Here, we present an engineered whole-lung tissue model used to evaluate the effects of cellular communities on tissue organization and alveolar barrier function. Engineered lungs were grown ex vivo on decellularized whole-lung matrices as structurally biomimetic, bioactive scaffolds. Histologic architecture of engineered lungs improved with the addition of alveolar macrophages, coming to resemble neonatal lung. Incorporating alveolar macrophages maximized the differentiation of native-like cellular communities, including alveolar type I-like epithelium, bronchioalveolar stem cells, microvascular endothelium, and pericytes. Cell-cell signaling in engineered lungs showed activation of developmental and inflammatory pathways, including WNT, Notch, and FGF signaling pathways. Engineered lungs containing alveolar macrophages showed a 668% improvement in measured alveolar barrier function. This work demonstrates the potential utility of engineered lung models for studying principles of tissue biology and pulmonary regeneration.

bioengineering↗

bioRxiv2024

Engineered prime editors with minimal genomic errors

Prime editors make programmed genome modifications by writing new sequences into extensions of nicked DNA 3 ends. These edited 3 new strands must displace competing 5 strands to install edits, yet a bias toward retaining the competing 5 strands hinders efficiency and can cause indel errors. Using rational design of the constituent Cas9-nickase to reposition prime editor nicks, we discovered that competing 5 strands are destabilized to favor the edited 3 new strands. We exploit this mechanism to engineer efficient prime editors with strikingly low indel errors. Combining this error-suppressing strategy with the latest efficiency-boosting architecture, we design a next- generation prime editor (vPE). Compared with previous editors, vPE features comparable efficiency yet up to 60-fold lower indel errors, enabling edit:indel ratios as high as 465:1. One Sentence SummaryPrime editors designed with repositioned DNA breaks nearly eliminate undesired genome editing errors

bioengineering↗

bioRxiv2023

Thermo-Responsive Polymers Targeting Inflammation in Murine Colitis

Targeting the site of inflammation is an ideal approach for treating inflammatory bowel disease (IBD). Inflammation targeting enables maximal drug-on-target effects while minimizing off-target side effects. Negatively charged drug carriers have been shown to facilitate drug delivery to inflamed colon mucosa after local administration. To modulate the negative charges and integrate responsiveness to stimuli, here we describe thermo-responsive, inflammation-targeting (TRIT) hydrogels based on functionalized poly(N-isopropylacrylamide-co-methacrylic acid) (PNIPAM-MAA). We show that both chemical modification types and polymer molecular weights affect the resultant microgels adhesion to the inflamed colon in dextran sulfate sodium (DSS)-induced murine colitis in vivo. Further, we quantified the correlations between microgels adhesion and colitis severity for individual mice, demonstrating that the microgels adhesion correlated directly with weight loss percentage in DSS-treated mice. By exploiting charge-mediated interaction and thermo-responsiveness, TRIT hydrogels represent a promising strategy to target inflamed colon mucosa as a drug delivery platform for colonic IBD treatment. TeaserThis study developed thermo-responsive, inflammation-targeting (TRIT) hydrogels that harness charge-mediated interaction and sol-to-gel transition to target inflamed colon mucosa as a new approach for treating inflammatory bowel disease.

bioengineering↗

bioRxiv2023

Electroadhesive hydrogel interface for prolonged mucosal theranostics

Establishing a robust and intimate mucosal interface that allows medical devices to remain within lumen-confined organs for extended periods has valuable applications, particularly for gastrointestinal (GI) theranostics. Here, we report the development of e-GLUE, an electroadhesive hydrogel interface for robust and prolonged mucosal retention following electrical activation. Notably, this novel mucosal adhesion mechanism can increase the adhesion energy of hydrogels on the mucosa by up to 30-fold and enable in vivo GI retention of e-GLUE devices for up to 30 days. Strong mucosal adhesion occurs within one minute of electrical activation, despite the presence of luminal fluid, mucus exposure, and organ motility, thereby ensuring compatibility with complex in vivo environments. In swine studies, we demonstrate the utility of e-GLUE for mucosal hemostasis, sustained local delivery of therapeutics, and intimate biosensing in the GI tract. This system can enable improved treatments for various health conditions, including gastrointestinal bleeding, inflammatory bowel disease, and diagnostic applications in the GI tract and beyond.

bioengineering↗

bioRxiv2023

Intracellular Proteomics and Extracellular Vesiculomics as a Metric of Disease Recapitulation in 3D Bioprinted Aortic Valve Arrays

In calcific aortic valve disease (CAVD), mechanosensitive valvular cells respond to fibrosis- and calcification-induced tissue stiffening, further driving pathophysiology. No pharmacotherapeutics are available to treat CAVD, due to the lack of: 1) appropriate experimental models that recapitulate this complex environment; and 2) benchmarking novel engineered AV-model performance. We established a biomaterial-based CAVD model mimicking the biomechanics of the human AV disease-prone fibrosa layer, 3D-bioprinted into 96-well arrays. LC-MS/MS analyses probed the cellular proteome and vesiculome to compare the 3D-bioprinted model vs. traditional 2D monoculture, against human CAVD tissue. The 3D-bioprinted model highly recapitulated the CAVD cellular proteome (94% vs. 70% of 2D proteins). Integration of cellular/vesicular datasets identified known and novel proteins ubiquitous to AV calcification. This study explores how 2D vs. 3D-bioengineered systems recapitulate unique aspects of human disease, positions multi-omics as a novel technique for the evaluation of high throughput-based bioengineered model systems and potentiates future drug discovery.

bioengineering↗

bioRxiv2022

Engineered retrovirus-like Arc extracellular vesicles for the in vivo targeted delivery of mRNA into the brain

Systemic delivery of mRNAs into disease neurons is first limited by the blood-brain-barrier (BBB). Leukocyte-derived extracellular vesicles (EVs) can cross the BBB at inflammatory sites, emerging as promising carriers to target the disease brain. However, efficient mRNA loading into EVs and their uptake by neurons remain challenges. Here we incorporated inside EVs the endogenous retrovirus-like Arc protein capsids, stabilized by Arc 5UTR RNA elements, to effectively load and deliver mRNAs. Produced from self-derived leukocytes, engineered retrotransposon Arc EVs (eraEVs) are immunologically inert with minimal clearance. Equipped with endothelial adhesion molecules from donor leukocytes, circulating eraEVs enter the brain enriching at neuro-inflammatory sites. During self-assembly, Arc recruits enveloping proteins onto eraEVs further promoting neuronal uptake. Possessing high effectiveness like viral vectors and biocompatibility as natural vesicles, eraEV-nanocarriers can be produced from virtually all donor cell types, potentially leading to the development of future clinical therapies for a range of diseases. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=125 SRC="FIGDIR/small/518870v2_ufig1.gif" ALT="Figure 1"> View larger version (35K): org.highwire.dtl.DTLVardef@260a4aorg.highwire.dtl.DTLVardef@16da754org.highwire.dtl.DTLVardef@4a79dorg.highwire.dtl.DTLVardef@1983da8_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗

bioRxiv2022

Absorbable Conductive Electrotherapeutic Scaffolds (ACES) for Enhanced Peripheral Nerve Regeneration and Stimulation

While peripheral nerve stimulation (PNS) has shown promise in applications ranging from peripheral nerve regeneration after injury to therapeutic organ stimulation, clinical implementation has been impeded by various technological limitations, including surgical placement, lead migration, and atraumatic removal. Here, we describe the design and validation of a new platform for nerve regeneration and interfacing: Absorbable, Conductive, Electrotherapeutic Scaffolds (ACES). ACES are comprised of an alginate/poly-acrylamide interpenetrating network hydrogel optimized for both open and minimally invasive percutaneous approaches. In a rodent model of sciatic nerve repair, ACES significantly improved motor and sensory recovery (p < 0.05), increased muscle mass (p < 0.05), and increased axonogenesis (p < 0.05). Triggered dissolution of ACES enabled atraumatic, percutaneous removal of leads at forces significantly lower than controls (p < 0.05). In a porcine model, ultrasound-guided percutaneous placement of leads with an injectable ACES near the femoral and cervical vagus nerves facilitated stimulus conduction at significantly greater lengths than saline controls (p < 0.05). Overall, ACES facilitated lead placement, stabilization, stimulation and atraumatic removal enabling therapeutic PNS as demonstrated in small and large animal models.

bioengineering↗

bioRxiv2022

Adversarial attacks and adversarial robustness in computational pathology

Artificial Intelligence (AI) can support diagnostic workflows in oncology by aiding diagnosis and providing biomarkers. AI applications are therefore expected to evolve from academic prototypes to commercial products in the coming years. However, AI applications are vulnerable to adversarial attacks, such as malicious interference with test data aiming to cause misclassifications. Therefore, it is essential for the use of AI-based diagnostic devices to secure them against such attacks before widespread use. Unfortunately, no resistant systems exist in computational pathology so far. To address this problem, we investigate the susceptibility of convolutional neural networks (CNNs) to multiple types of white- and black-box attacks. We demonstrate that both attacks can easily confuse CNNs in clinically relevant pathology tasks and impair classification performance. Classical adversarially robust training and dual batch normalization (DBN) are possible mitigation strategies but require precise knowledge of the type of attack used in the inference. We demonstrate that vision transformers (ViTs) perform equally well compared to CNNs at baseline and are orders of magnitude more robust to different types of white-box and black-box attacks. At a mechanistic level, we show that this is associated with a more robust latent representation of clinically relevant categories in ViTs compared to CNNs. Our results are in line with previous theoretical studies. We show that ViTs are robust learners in computational pathology. This implies that large-scale rollout of AI models in computational pathology should rely on ViTs rather than CNN-based classifiers to provide inherent protection against adversaries.

bioinformatics↗

bioRxiv2022

Altered DNA repair pathway engagement by engineered CRISPR-Cas9 nucleases

CRISPR-Cas9 introduces targeted DNA breaks that engage competing DNA repair pathways, producing a spectrum of imprecise insertion/deletion mutations (indels) and precise templated mutations (precise edits). The relative frequencies of these pathways are thought to primarily depend on genomic sequence and cell state contexts, limiting control over mutational outcomes. Here we report that engineered Cas9 nucleases that create different DNA break structures engage competing repair pathways at dramatically altered frequencies. We accordingly designed a Cas9 variant (vCas9) that produces breaks which suppress otherwise dominant nonhomologous end-joining (NHEJ) repair. Instead, breaks created by vCas9 are predominantly repaired by pathways utilizing homologous sequences, specifically microhomology-mediated end-joining (MMEJ) and homology-directed repair (HDR). Consequently, vCas9 enables efficient precise editing through HDR or MMEJ while suppressing indels caused by NHEJ in dividing and non-dividing cells. These findings establish a new paradigm of targeted nucleases custom-designed for specific mutational applications. TeaserCRISPR-Cas9 can be designed to make otherwise infrequent precise editing pathways dominant in dividing and non-dividing cells

bioengineering↗

bioRxiv2021

Benchmarking artificial intelligence methods for end-to-end computational pathology

Artificial intelligence (AI) can extract subtle visual information from digitized histopathology slides and yield scientific insight on genotype-phenotype interactions as well as clinically actionable recommendations. Classical weakly supervised pipelines use an end-to-end approach with residual neural networks (ResNets), modern convolutional neural networks such as EfficientNet, or non-convolutional architectures such as vision transformers (ViT). In addition, multiple-instance learning (MIL) and clustering-constrained attention MIL (CLAM) are being used for pathology image analysis. However, it is unclear how these different approaches perform relative to each other. Here, we implement and systematically compare all five methods in six clinically relevant end-to-end prediction tasks using data from N=4848 patients with rigorous external validation. We show that histological tumor subtyping of renal cell carcinoma is an easy task which approaches successfully solved with an area under the receiver operating curve (AUROC) of above 0.9 without any significant differences between approaches. In contrast, we report significant performance differences for mutation prediction in colorectal, gastric and bladder cancer. Weakly supervised ResNet-and ViT-based workflows significantly outperformed other methods, in particular MIL and CLAM for mutation prediction. As a reason for this higher performance we identify the ability of ResNet and ViT to assign high prediction scores to highly informative image regions with plausible histopathological image features. We make all source codes publicly available at https://github.com/KatherLab/HIA, allowing easy application of all methods on any end-to-end problem in computational pathology.

bioinformatics↗

bioRxiv2020

BBB pathophysiology independent delivery of siRNA in traumatic brain injury

Small interfering RNA (siRNA) represents a powerful strategy to mitigate the long-term sequelae of traumatic brain injury (TBI). However, poor permeability of siRNA across the blood brain barrier (BBB) poses a major hurdle. One approach to overcome this challenge involves treatment administration while the BBB is physically breached post-injury. However, this approach is only applicable to a subset of injuries with substantial BBB breach and can lead to variable therapeutic response due to the heterogeneity of physical breaching of BBB in TBI. Moreover, since physical breaching of BBB is transient, this approach offers a limited window for therapeutic intervention, which is not ideal as repeated dosing beyond the transient window of physically breached BBB might be required. Herein, we report a nanoparticle platform for BBB pathophysiology-independent delivery of siRNA in TBI. We achieved this by combined modulation of surface chemistry and coating density, which maximized the active transport of nanoparticles across BBB. Intravenous injection of engineered nanoparticles, within or outside the window of physically breached BBB in TBI mice resulted in 3-fold higher brain accumulation compared to conventional PEGylated nanoparticles and demonstrated up to 50% gene silencing. To our knowledge, this is the first reported example of BBB pathophysiology-independent drug delivery in TBI, and the first time combined modulation of surface chemistry and coating density has been shown to tune BBB penetration of nanoparticles. Taken together, our approach offers a clinically relevant approach to develop siRNA therapeutics for preventing long-term effects of TBI and deserves further exploration.Competing Interest StatementJMK has been a paid consultant and or equity holder for multiple biotechnology companies (listed here https://www.karplab.net/team/jeff-karp). The interests of JMK were reviewed and are subject to a management plan overseen by his institutions in accordance with its conflict of interest policies. N.J., J.MK., W.L., R.M., J.Q. and R.L. have one unpublished patent based on the nanoparticle work presented in this manuscript. For a list of entities with which R.L. is involved, compensated or uncompensated, see www.dropbox.com/s/yc3xqb5s8s94v7x/Rev%20Langer%20COI.pdf?dl=0.View Full Text

bioengineering↗

bioRxiv2020

Reverse Pneumatic Artificial Muscles for Application in Low-Cost Artificial Respirators

One of the main challenges associated with mechanical ventilators is their limited availability in pandemics and other emergencies. Therefore, there is a great demand for mechanical ventilators to address this issue. In this work, we propose a low-cost, portable, yet high-performance design for a volume-controlled mechanical ventilator. We are employing pneumatic artificial muscles, such as air cylinders, in the reverse mode of operation to achieve mechanical ventilation. The current design of the device can operate in two modes: controlled mode and assisted mode. Unlike most ICU ventilators, our device does not need a high-pressure air pipeline to operate. With the current design, mechanical ventilation for respiration rate ranging from 10 b/min to 30 b/min with a tidal volume range of 150 mL to 1000 mL and I:E ratio of 1:1 to 1:5 can be performed. We achieved a total cost of less $400 USD to make one device. We estimate the device to cost less than $250 USD when produced in larger volumes.

bioengineering↗