- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Epitaxial Graphene Sensors Combined with 3D Printed Microfluidic Chip for Heavy Metals Detection
摘要： Two-dimensional materials may constitute key elements in the development of a sensing platform where extremely high sensitivity is required, since even minimal chemical interaction can generate appreciable changes in the electronic state of the material. In this work, we investigate the sensing performance of epitaxial graphene on Si-face 4H-SiC (EG/SiC) for liquid-phase detection of heavy metals (e.g., Pb). The integration of preparatory steps needed for sample conditioning is included in the sensing platform, exploiting fast prototyping using a 3D printer, which allows direct fabrication of a microfluidic chip incorporating all the features required to connect and execute the Lab-on-chip (LOC) functions. It is demonstrated that interaction of Pb2+ ions in water-based solutions with the EG enhances its conductivity exhibiting a Langmuir correlation between signal and Pb2+ concentration. Several concentrations of Pb2+ solutions ranging from 125 nM to 500 μM were analyzed showing good stability and reproducibility over time.
关键词： heavy metals detection,3D printed flow cell,reusable lab-on-chip,epitaxial graphene,high sensitivity
更新于2025-09-23 15:23:52
-
Monolithic Wafer Scale Integration of Silicon Nanoribbon Sensors with CMOS for Lab-on-Chip Application
摘要： Silicon ribbons (SiRi) have been well-established as highly sensitive transducers for biosensing applications thanks to their high surface to volume ratio. However, selective and multiplexed detection of biomarkers remains a challenge. Further, very few attempts have been made to integrate SiRi with complementary-metal-oxide-semiconductor (CMOS) circuits to form a complete lab-on-chip (LOC). Integration of SiRi with CMOS will facilitate real time detection of the output signal and provide a compact small sized LOC. Here, we propose a novel pixel based SiRi device monolithically integrated with CMOS ?eld-effect-transistors (FET) for real-time selective multiplexed detection. The SiRi pixels are fabricated on a silicon-on-insulator wafer using a top-down method. Each pixel houses a control FET, ?uid-gate (FG) and SiRi sensor. The pixel is controlled by simultaneously applying frontgate (VG) and backgate voltage (VBG). The liquid potential can be monitored using the FG. We report the transfer characteristics (ID-VG) of N- and P-type SiRi pixels. Further, the ID-VG characteristics of the SiRis are studied at different VBG. The application of VBG to turn ON the SiRi modulates the subthreshold slope (SS) and threshold voltage (VTH) of the control FET. Particularly, N-type pixels cannot be turned OFF due to the control NFET operating in the strong inversion regime. This is due to large VBG (≥25 V) application to turn ON the SiRi sensor. Conversely, the P-type SiRi sensors do not require large VBG to switch ON. Thus, P-type pixels exhibit excellent ION/IOFF ≥ 106, SS of 70–80 mV/dec and VTH of 0.5 V. These promising results will empower the large-scale cost-ef?cient production of SiRi based LOC sensors.
关键词： silicon ribbon biosensor,SiRi backgate mode,silicon ribbon pixel,selective multiplexed detection,SiRi CMOS integration,SiRi frontgate mode,lab-on-chip
更新于2025-09-23 15:22:29
-
[IEEE 2019 SBFoton International Optics and Photonics Conference (SBFoton IOPC) - Sao Paulo, Brazil (2019.10.7-2019.10.9)] 2019 SBFoton International Optics and Photonics Conference (SBFoton IOPC) - Production of a microfluidic random laser using ultrashort laser pulses
摘要： A random rhodamine laser system is produced on board of a femtosecond laser machined microfluidic system. When pumped by a nanosecond pulsed laser beam at 532 nm, laser emission at 610 nm is observed together with the linewidth narrowing typical of random lasers. The system can be easily integrated as an optofluidic component into microfluidic circuits for assessment of optical parameters on board of the lab-on-chip.
关键词： lab-on-chip,random lasers,microfluidics
更新于2025-09-16 10:30:52
-
Ruthenium Oxide pH Sensing for Organs-On-Chip Studies
摘要： A ruthenium oxide (RuOx) electrode is being developed as potentiometric pH sensor for organs-on-chip applications. Open-circuit potential (OCP) of the RuOx electrode showed a response of ?58.05 mV/pH, with no cross-sensitivity to potentially interfering/complexing ions (tested were lithium, sulfate, chloride, and calcium ions). Similar response was observed in complex biological medium. The electrode stored in liquid had a long-term drift of ?0.8 mV/hour (corresponding to ΔpH of 0.013/hour) and response time in complex biological medium was 3.7 s. Minimum cross-sensitivity to oxygen was observed as the OCP shifted ~3 mV going from deoxygenated to oxygenated solution. This response is one magnitude lower than previously reported for metal-oxide pH sensors. Overall, the RuOx pH sensor has proven to be a suitable pH sensor for organs-on-chip applications.
关键词： potentiometric sensor,lab-on-chip,organs-on-chip,ruthenium oxide,pH sensor
更新于2025-09-04 15:30:14