Showing papers by "Tingrui Pan published in 2021"
TL;DR: In the past decade, a brand-new pressure and tactile-sensing modality known as iontronic sensing has emerged, utilizing the supercapacitive nature of the electrical double layer (EDL) that occurs at the electrolytic-electronic interface, leading to ultrahigh device sensitivity, high noise immunity, high resolution, high spatial definition, optical transparency, and responses to both static and dynamic stimuli, in addition to thin and flexible device architectures.
Abstract: Over the past decade, a brand-new pressure- and tactile-sensing modality, known as iontronic sensing has emerged, utilizing the supercapacitive nature of the electrical double layer (EDL) that occurs at the electrolytic-electronic interface, leading to ultrahigh device sensitivity, high noise immunity, high resolution, high spatial definition, optical transparency, and responses to both static and dynamic stimuli, in addition to thin and flexible device architectures. Together, it offers unique combination of enabling features to tackle the grand challenges in pressure- and tactile-sensing applications, in particular, with recent interest and rapid progress in the development of robotic intelligence, electronic skin, wearable health as well as the internet-of-things, from both academic and industrial communities. A historical perspective of the iontronic sensing discovery, an overview of the fundamental working mechanism along with its device architectures, a survey of the unique material aspects and structural designs dedicated, and finally, a discussion of the newly enabled applications, technical challenges, and future outlooks are provided for this promising sensing modality with implementations. The state-of-the-art developments of the iontronic sensing technology in its first decade are summarized, potentially providing a technical roadmap for the next wave of innovations and breakthroughs in this field.
104 citations
TL;DR: The experimental results demonstrate that the proposed ELM method can improve the prediction accuracy of resource optimization models of complex industrial processes, and realize energy-saving and carbon emissions reduction.
41 citations
TL;DR: In terms of operation procedure, cost, and reaction time, the μFEC method was superior to the current methods for PSA detection and shows great potential for practical clinical application in the future.
Abstract: Prostate-specific antigen (PSA) is the most widely used biomarker for the early diagnosis of prostate cancer. Existing methods for PSA detection are burdened with some limitations and require improvement. Herein, we developed a novel microfluidic-electrochemical (μFEC) detection system for PSA detection. First, we constructed an electrochemical biosensor based on screen-printed electrodes (SPEs) with modification of gold nanoflowers (Au NFs) and DNA tetrahedron structural probes (TSPs), which showed great detection performance. Second, we fabricated microfluidic chips by DNA TSP-Au NF-modified SPEs and a PDMS layer with designed dense meandering microchannels. Finally, the μFEC detection system was achieved based on microfluidic chips integrated with the liquid automatic conveying unit and electrochemical detection platform. The μFEC system we developed acquired great detection performance for PSA detection in PBS solution. For PSA assays in spiked serum samples of the μFEC system, we obtained a linear dynamic range of 1-100 ng/mL with a limit of detection of 0.2 ng/mL and a total reaction time <25 min. Real serum samples of prostate cancer patients presented a strong correlation between the "gold-standard" chemiluminescence assays and the μFEC system. In terms of operation procedure, cost, and reaction time, our method was superior to the current methods for PSA detection and shows great potential for practical clinical application in the future.
25 citations
TL;DR: A novel programmable on-demand droplet generator based on a microfluidic adaptive printing system (MAP-ddPCR) to create a cost-effective ddPCR process that produces reliable data using gradient concentrations of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) in human genomic cDNA.
Abstract: Droplet digital polymerase chain reaction (ddPCR) is a rapidly developing technology used for accurate, quantitative analysis of rare samples. However, ddPCR has only been implemented in research field but rarely in clinical trials due to its relatively high cost and negative user experiences compared with qPCR. We developed a novel programmable on-demand droplet generator based on a microfluidic adaptive printing system (MAP-ddPCR) to create a cost-effective ddPCR process. This process easily produces low-volume, spot-on-demand droplet dispensing and data analysis using simple equipment and workflow. Compared with the existing droplet generation systems that rely on surface-assistant, the proposed MAP system generates a variety of droplet arrays on regular non-surface-treated glass slides. This system directly processes PCR and performs data analysis without requiring a secondary droplets transfer. The static and independent properties of each droplet dramatically avoid cross-contamination during PCR, provide the opportunity to trace droplets in real-time and simplify the analysis. We demonstrated that the MAP-ddPCR produces reliable data using gradient concentrations of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) in human genomic cDNA. These concentrations were further verified by quantitative PCR (qPCR). In addition, a very low viral load of SARS-CoV-2 was precisely detected and quantified by the MAP-ddPCR system. Finally, this system is affordable and simpler to integrate compared to other more expensive commercial digital PCR methods. Therefore, the proposed MAP-ddPCR system is expected to have a significant impact on market applications.
9 citations
TL;DR: A smart glasses wearable developed, incorporating a flexible and sensitive pressure sensor, to monitor blink patterns by continuously detecting ocular muscular movements, referred to as blink-sensing glasses, can be potentially used as a new clinical and research monitoring tool for continuous eye blink analysis.
9 citations
TL;DR: In this article, the authors presented a system incorporating a robotic-microfluidic interface (RoMI) and a modular hybrid microfluideic chip that embeds a highly sensitive nanofibrous membrane, referred to as the Robotic ELISA, to achieve human-free sample-to-answer ELISA tests in a fully programmable and automated manner.
Abstract: Enzyme-linked immunosorbent assays (ELISA), as one of the most used immunoassays, have been conducted ubiquitously in hospitals, research laboratories, etc. However, the conventional ELISA procedure is usually laborious, occupies bulky instruments, consumes lengthy operation time, and relies considerably on the skills of technicians, and such limitations call for innovations to develop a fully automated ELISA platform. In this paper, we have presented a system incorporating a robotic-microfluidic interface (RoMI) and a modular hybrid microfluidic chip that embeds a highly sensitive nanofibrous membrane, referred to as the Robotic ELISA, to achieve human-free sample-to-answer ELISA tests in a fully programmable and automated manner. It carries out multiple bioanalytical procedures to replace the manual steps involved in classic ELISA operations, including the pneumatically driven high-precision pipetting, efficient mixing and enrichment enabled by back-and-forth flows, washing, and integrated machine vision for colorimetric readout. The Robotic ELISA platform has achieved a low limit of detection of 0.1 ng/mL in the detection of a low sample volume (15 μL) of chloramphenicol within 20 min without human intervention, which is significantly faster than that of the conventional ELISA procedure. Benefiting from its modular design and automated operations, the Robotic ELISA platform has great potential to be deployed for a broad range of detections in various resource-limited settings or high-risk environments, where human involvement needs to be minimized while the testing timeliness, consistency, and sensitivity are all desired.
7 citations
TL;DR: The recent development of synthetic biology has expanded the capability to design and construct protein networks outside of living cells from the bottom-up as mentioned in this paper, which has enabled us to assemble protein networks for the basic study of cellular pathways, expression of proteins outside cells, and building tissue materials.
6 citations
TL;DR: In this article, an intelligent theranostic compression device, referred to as iWRAP, with the built-in capacity of real-time vital sign monitoring together with auto-adjustable compression level was developed.
Abstract: Objective: Venous Thromboembolism (VTE) is a commonly underdiagnosed disease with severe consequences and an exceedingly high mortality rate. Conventional compression wraps are devised for therapeutic purpose but lack diagnostic capacity. Recent advances in flexible electronics and wearable technologies offer many possibilities for chronic disease management. In particular, vital signs have been studied to show a strong correlation with the risk of VTE patients. In this study, we aim to develop an intelligent theranostic compression device, referred to as iWRAP, with the built-in capacity of real-time vital sign monitoring together with auto-adjustable compression level. Methods: An instantaneous pneumatic feedback control with a high-resolution pressure sensor is integrated to provide a highly stabilized compression level at the prescribed interface pressure for an improved therapeutic outcome. Meanwhile, arterial pulse waveforms extracted from the pressure readings from the smart compression device can be utilized to derive the body vital signs, including heart rate (HR), respiratory rate (RR) and blood pressure (BP). Results: A reliable delivery of the targeted compression level within ±5% accuracy in the range of 20-60 mmHg has been achieved through the feedback of the interface pressure. Both HR and RR have been measured within clinical-grade accuracies. Moreover, BP estimated using an ALA model has been achieved at low compression levels, which is also within a clinical-acceptable accuracy. The acquired vital information has been instantaneously fit into the clinically acceptable criteria for life-threatening PE risk with timely assessments. Conclusion: The iWRAP has shown the potential to become the first theranostic wearable device with both continuous delivery of accurate and effective compression therapy and real-time monitoring of life-threatening conditions for VTE patients.
6 citations
TL;DR: In this paper, a real-time cellular recognition and microfluidic impact printing (MIP) was used to isolate single cells with high efficiency and high throughput in a label-free manner.
Abstract: Analysis of cellular components at the single-cell level is important to reveal cellular heterogeneity. However, current technologies to isolate individual cells are either label-based or have low performance. Here, we present a novel technique by integrating real-time cellular recognition and microfluidic impact printing (MIP) to isolate single cells with high efficiency and high throughput in a label-free manner. Specifically, morphological characteristics of polystyrene beads and cells, computed by an efficient image processing algorithm, are utilized as selection criteria to identify target objects. Subsequently, each detected single-cell object in the suspension is ejected from the microfluidic channel by impact force. It has been demonstrated that the single-cell isolating system has the ability to encapsulate polystyrene beads in droplets with an efficiency of 95%, while for HeLa cells, this has been experimentally measured as 90.3%. Single-cell droplet arrays are generated at a throughput of 2 Hz and 96.6% of the cells remain alive after isolation. This technology has significant potential in various emerging applications, including single-cell omics, tissue engineering, and cell-line development.
5 citations
14 Mar 2021
TL;DR: This paper gives an overview of emerging optofluidic technologies for biodiagnostic applications with the focus on three common types of biomarkers: nucleic acid, protein, and cell and discusses the challenges, opportunities, and future perspectives of this field.
Abstract: The unprecedented global COVID‐19 pandemic strongly argues the critical need for innovative diagnostic tools meeting the requirement of test speed, accuracy, and throughput. Owing to the integration of optics and microfluidics technologies, optofluidic technology enables highly precise flow manipulation and highly sensitive signal detection at the microscale, thus offering the promising potential for developing biodiagnostic applications. Research toward this direction is fast growing into an emerging area. In this paper, we give an overview of emerging optofluidic technologies for biodiagnostic applications with the focus on three common types of biomarkers: nucleic acid, protein, and cell. We conclude by discussing the challenges, opportunities, and future perspectives of this field.
5 citations
23 Feb 2021
TL;DR: The study of protein diffusion in polyacrylonitrile (PAN) nanofibrous membranes produced under varied humidity and polymer concentration of electrospinning revealed that heterogeneous structures of the nanofIBrous membranes possess much smaller effective pore sizes than the measured pores, which significantly affects the diffusion of large molecules through the system though sizes of proteins and pH conditions also have great impacts.
Abstract: Porous nanofibrous membranes have ultrahigh specific surface areas and could be broadly employed in protein purification, enzyme immobilization, and biosensors with enhanced selectivity, sensitivit...
TL;DR: The digital droplet infusion (DDI) device is presented, a low-cost, high-precision digital infusion system, utilizing a microfluidic discretization unit to convert continuous flow into precisely delivered droplet aliquots and a valving unit to control the duration and frequency of flow discretized.
Abstract: Infusion pumps have been widely used in clinical settings for the administration of medications and fluids. We present the digital droplet infusion (DDI) device, a low-cost, high-precision digital infusion system, utilizing a microfluidic discretization unit to convert continuous flow into precisely delivered droplet aliquots and a valving unit to control the duration and frequency of flow discretization. The DDI device relies on a distinct capillarity-dominated process of coalescence and pinch-off of droplets for flow digitization, which is monitored by a pair of conductive electrodes located before and after the junction. The digital feedback-controlled flow rate can be employed to adjust a solenoid valve for refined infusion management. With this unique digital microfluidic approach, the DDI technology enables a simple yet powerful infusion system with an ultrahigh resolution of digital droplet transfer volume, as small as 57 nL, which is three orders of magnitude lower than that of clinical standard infusion pumps, as well as a wide range of digitally adjustable infusion rates ranging from 0.1 mL h-1 to 10 mL h-1, in addition to an array of programmable infusion profiles and safety features. Its modular design enables fast assembly using only off-the-shelf and 3D-printed components. Overall, benefiting from its simple device architecture and excellent infusion performance, the DDI technology has great potential to become the next-generation clinical standard for drug delivery with its high precision and ultimate portability at a low cost.