Research Interests

Biomedical Devices Integration

The development of wearable biomedical devices requires not only technological innovation but also interdisciplinary collaboration and a deep understanding of markets, users, and regulatory pathways. Our lab has extensive experience in designing and integrating wearable systems by bringing together experts in chemical, electrical, mechanical, and software engineering to create devices that transition from the lab to real-world use.

We have successfully developed and commercialized multiple biomedical devices, including: 1) A wireless FeNO Analyzer for sensitive detection of nitric oxide in breath at parts-per-billion levels, enabling asthma management. 2) The Portable Metabolic Tracker (Breezing) and the world’s first Wearable Metabolic Tracker (Breezing Med™, FDA 510k cleared), which monitor oxygen consumption and carbon dioxide production in breath for personal health management. 3) A wearable badge device under development for monitoring workers’ exposure to multiple hazardous chemicals (NO₂, O₃, HCHO, CO, SO₂, NH₃) in industrial workplaces, enhancing occupational safety.

In parallel, we leverage data science to transform continuous data streams from wearables into clinical insights and predictive models for personalized healthcare. Our lab developed a principal component analysis (PCA)-based algorithm to extract unique respiration patterns from wearable mask devices. By incorporating variables from frequency, amplitude, hybrid, and waveform domains, this approach enables effective screening, diagnosis, and management of respiratory diseases such as asthma and COPD. These methods highlight the power of wearable devices not just as sensors, but as data-driven platforms for clinical decision-making.

Over the past decade, wearable healthcare technologies have rapidly evolved, and our lab has been at the forefront of this transformation. In addition to Breezing Med™, we have developed a wearable wristband for transdermal volatile biomarker detection, validated in clinical studies for noninvasive, cost-effective dietary and disease management. We also advanced wearable communication ecosystems, optimizing Bluetooth Low Energy (BLE) protocols to reduce data packet loss across Android/iOS platforms—improving reliability across wearable devices. Most recently, we created a portable, 2D diffusion-based colorimetric device for continuous, multiplexed air quality monitoring.

Our vision is to create fully integrated wearable devices that seamlessly connect sensors, electronics, and data science to improve health, ensure workplace safety, and enable personalized, evidence-based medicine.

Wearable Mask Device for Respiration Pattern Recognition 

Transdermal Biomarker Monitor

Multiplexed Air Pollution Monitor

Bluetooth Low EnergyBased Wearable Ecosystem

Related Publications:

1. Vishal Varun Tipparaju, Di Wang, Jingjing Yu, Fang Chen, Francis Tsow, Erica Forzani, Nongjian Tao, and Xiaojun Xian*, Respiration Pattern Recognition by Wearable Mask Device, Biosensors and Bioelectronics, 169, 112590 (2020)

2. Vishal Varun Tipparaju, Sabrina Jimena Mora, Jingjing Yu, Francis Tsow, Xiaojun Xian*, Wearable Transcutaneous CO2 Monitor Based on Miniaturized Nondispersive Infrared Sensor, IEEE Sensors Journal, 21, 17327-17334 (2021)

3. Vishal Varun Tipparaju, Kyle Mallires, Di Wang, Francis Tsow, and Xiaojun Xian*, Mitigation of Data Packet Losses in Bluetooth Low Energy for Wearable Ecosystem, Biosensors, 11, 350 (2021)

4. Xiaojun Xian, Devon Bridgeman, Francis Tsow, Erica S. Forzani, Nongjian Tao, Self-Contained Wearable Metabolic Analyzer, International Patent, Application Number PCT/US19/55235 (2019)

5. Jingjing Yu, Di Wang, Vishal Varun Tipparaju, Wonjong Jung, and Xiaojun Xian*, Detection of Transdermal Biomarkers of Macronutrients Intake Using Gradient-Based Colorimetric Array Sensor, Biosensors and Bioelectronics, 195, 113650 (2022)

6. Jingjing Yu, Wei Ding, Francis Tsow, Chinmay Chandrakant Dixit, Vishal Varun Tipparaju, Erica Forzani, and Xiaojun Xian*, Low-Cost and Point-of-Use Sensing Device Based on 2D Diffusion-Controlled Colorimetric Sensing Array for Continuous and Multiplexed Air Pollution Monitoring, ACS ES&T Engineering, 4, 3118-3126 (2024) (https://doi.org/10.1021/acsestengg.4c00416)