Most biological tissues are supple and elastic, while current electronic devices fabricated by semiconductors and metals are usually stiff and brittle. As a result, implanted electronic devices can irritate and damage...Most biological tissues are supple and elastic, while current electronic devices fabricated by semiconductors and metals are usually stiff and brittle. As a result, implanted electronic devices can irritate and damage surrounding tissues, causing immune reaction and scarring. In this work, we develop stretchable microelectrode arrays, with the development of a novel soft lithography technology, which are designed and fabricated with a polymer/stretchable metal/polymer sandwich structure. With the great deformability of stretch, compression, bend and twisting, while preserving electrical property, this technology overcomes the fundamental mismatch of mechanical properties between biological tissues and electronic devices, and provides highly-compliant, confonnal and stretchable bio-electronic interfaces. Here we also describe the following three applications of the stretchable electrode arrays： a. monitoring intracranial electroencephalography （EEG）; b. stimulating peripheral nerves to drive muscles; c. monitoring epicardial electrocardiography （ECG）. Stretchable microelectrode arrays create a promising field in biomedical applications for its better modulus match with biological tissues and robust mechanical and electrical properties. They allow for construction of electronic integrated circuits spread over on complex and dynamic curved surfaces, providing a much friendlier bio-electronic interface for diagnosis, treatment and in- telligent bio-control.展开更多
Semi-invasive blood sampling devices mimic the way female mosquitoes extract blood from a host. They generally consist of a microneedle, a microactuator for needle insertion, a blood extraction mechanism and a blood g...Semi-invasive blood sampling devices mimic the way female mosquitoes extract blood from a host. They generally consist of a microneedle, a microactuator for needle insertion, a blood extraction mechanism and a blood glucose sensor. These devices have great potential to overcome the major disadvantages of several current blood glucose monitoring methods. Over last two decades, extensive research has been made in all of these related fields. More recently, several wearable devices for semi-invasive blood sampling have been developed. This review aims at summarizing the current state-of-the-art development and utilization of such wearable devices for continuous monitoring of blood glucose levels, with a special attention on design considerations, fabrication technologies and testing methods.展开更多
In clinical practice,examination of the hemorrhagic spot (HS) remains difficult.In this paper,we describe a remote controlled capsule (RCC) micro-system with an automated,color-based sensor to identify and localize th...In clinical practice,examination of the hemorrhagic spot (HS) remains difficult.In this paper,we describe a remote controlled capsule (RCC) micro-system with an automated,color-based sensor to identify and localize the HS of the gastrointestinal (GI) tract.In vitro testing of the detecting sensor demonstrated that it was capable of discriminating mimetic intestinal fluid (MIF) with and without the hemoglobin (Hb) when the concentration of Hb in MIF was above 0.05 g/ml.Therefore,this RCC system is able to detect the relatively accurate location of the HS in the GI tract.展开更多
This paper presents a micro packaged MEMS pressure sensor for intracranial pressure measurement which belongs to BioMEMS. It can be used in lumbar puncture surgery to measure intracranial pressure. Minia- turization i...This paper presents a micro packaged MEMS pressure sensor for intracranial pressure measurement which belongs to BioMEMS. It can be used in lumbar puncture surgery to measure intracranial pressure. Minia- turization is key for lumbar puncture surgery because the sensor must be small enough to allow it be placed in the reagent chamber of the lumbar puncture needle. The size of the sensor is decided by the size of the sensor chip and package. Our sensor chip is based on silicon piezoresistive effect and the size is 400 × 400 μm2. It is much smaller than the reported polymer intracranial pressure sensors such as liquid crystal polymer sensors. In terms of package, the traditional dual in-line package obviously could not match the size need, the minimal size of recently reported MEMS-based intracranial pressure sensors after packaging is 10 × 10 mm2. In this work, we are the first to introduce a quad flat no-lead package as the package form of piezoresistive intracranial pressure sensors, the whole size of the sensor is minimized to only 3 × 3 mm2. Considering the liquid measurement environment, the sensor is gummed and waterproof performance is tested; the sensitivity of the sensor is 0.9 × 10-2 mV/kPa.展开更多
Mechanical stimulation has been imposed on living cells using several approaches.Most early investigations were conducted on groups of cells,utilizing techniques such as substrate deformation and flow-induced shear.To...Mechanical stimulation has been imposed on living cells using several approaches.Most early investigations were conducted on groups of cells,utilizing techniques such as substrate deformation and flow-induced shear.To investigate the properties of cells individually,many conventional techniques were utilized,such as AFM,optical traps/optical tweezers,magnetic beads,and micropipette aspiration.In specific mechanical interrogations,microelectro-mechanical systems(MEMS)have been designed to probe single cells in different interrogation modes.To exert loads on the cells,these devices often comprise piezo-electric driven actuators that attach directly to the cell or move a structure on which cells are attached.Uniaxial and biaxial pullers,micropillars,and cantilever beams are examples of MEMS devices.In this review,the methodologies to analyze single cell activity under external loads using microfabricated devices will be examined.We will focus on the mechanical interrogation in three different regimes:compression,traction,and tension,and discuss different microfabricated platforms designed for these purposes.展开更多
基金National Natural Science Foundation of China (No. 61102042)Youth Innovation Foundation of Chinese Academy of SciencesShenzhen"Peacock Plan"to Z.Y.
文摘Most biological tissues are supple and elastic, while current electronic devices fabricated by semiconductors and metals are usually stiff and brittle. As a result, implanted electronic devices can irritate and damage surrounding tissues, causing immune reaction and scarring. In this work, we develop stretchable microelectrode arrays, with the development of a novel soft lithography technology, which are designed and fabricated with a polymer/stretchable metal/polymer sandwich structure. With the great deformability of stretch, compression, bend and twisting, while preserving electrical property, this technology overcomes the fundamental mismatch of mechanical properties between biological tissues and electronic devices, and provides highly-compliant, confonnal and stretchable bio-electronic interfaces. Here we also describe the following three applications of the stretchable electrode arrays： a. monitoring intracranial electroencephalography （EEG）; b. stimulating peripheral nerves to drive muscles; c. monitoring epicardial electrocardiography （ECG）. Stretchable microelectrode arrays create a promising field in biomedical applications for its better modulus match with biological tissues and robust mechanical and electrical properties. They allow for construction of electronic integrated circuits spread over on complex and dynamic curved surfaces, providing a much friendlier bio-electronic interface for diagnosis, treatment and in- telligent bio-control.
文摘Semi-invasive blood sampling devices mimic the way female mosquitoes extract blood from a host. They generally consist of a microneedle, a microactuator for needle insertion, a blood extraction mechanism and a blood glucose sensor. These devices have great potential to overcome the major disadvantages of several current blood glucose monitoring methods. Over last two decades, extensive research has been made in all of these related fields. More recently, several wearable devices for semi-invasive blood sampling have been developed. This review aims at summarizing the current state-of-the-art development and utilization of such wearable devices for continuous monitoring of blood glucose levels, with a special attention on design considerations, fabrication technologies and testing methods.
基金Project supported by the National Natural Science Foundation of China (Nos. 30700160 and 30970883)the Postdoctoral Science Foundation of China (Nos. 20070420718 and 200801225)+1 种基金Chongqing University Postgraduates’ Science and Innovation Fund (No. 2008 01A1B0250284)the Specialized Research Fund for the Doctoral Program of Higher Education (No. 20070611045), China
文摘In clinical practice,examination of the hemorrhagic spot (HS) remains difficult.In this paper,we describe a remote controlled capsule (RCC) micro-system with an automated,color-based sensor to identify and localize the HS of the gastrointestinal (GI) tract.In vitro testing of the detecting sensor demonstrated that it was capable of discriminating mimetic intestinal fluid (MIF) with and without the hemoglobin (Hb) when the concentration of Hb in MIF was above 0.05 g/ml.Therefore,this RCC system is able to detect the relatively accurate location of the HS in the GI tract.
基金Project supported by the National Natural Science Foundation of China(Nos.61025021,61434001)the ‘Thousands Talents’ Program for Pioneer Researchers and Its Innovation Team,China
文摘This paper presents a micro packaged MEMS pressure sensor for intracranial pressure measurement which belongs to BioMEMS. It can be used in lumbar puncture surgery to measure intracranial pressure. Minia- turization is key for lumbar puncture surgery because the sensor must be small enough to allow it be placed in the reagent chamber of the lumbar puncture needle. The size of the sensor is decided by the size of the sensor chip and package. Our sensor chip is based on silicon piezoresistive effect and the size is 400 × 400 μm2. It is much smaller than the reported polymer intracranial pressure sensors such as liquid crystal polymer sensors. In terms of package, the traditional dual in-line package obviously could not match the size need, the minimal size of recently reported MEMS-based intracranial pressure sensors after packaging is 10 × 10 mm2. In this work, we are the first to introduce a quad flat no-lead package as the package form of piezoresistive intracranial pressure sensors, the whole size of the sensor is minimized to only 3 × 3 mm2. Considering the liquid measurement environment, the sensor is gummed and waterproof performance is tested; the sensitivity of the sensor is 0.9 × 10-2 mV/kPa.
基金We acknowledge the funding support from the NSF(Awards 1826135,1936065)the NIH National Institutes of General Medical Sciences P20GM113126,and P30GM127200We acknowledge funding support from the Nebraska Collaborative Initiative and EPSCoR FIRST award.G.M.and J.R.are funded by the NSF Graduate Research Fellowship(Awards 2034837,2034837).
文摘Mechanical stimulation has been imposed on living cells using several approaches.Most early investigations were conducted on groups of cells,utilizing techniques such as substrate deformation and flow-induced shear.To investigate the properties of cells individually,many conventional techniques were utilized,such as AFM,optical traps/optical tweezers,magnetic beads,and micropipette aspiration.In specific mechanical interrogations,microelectro-mechanical systems(MEMS)have been designed to probe single cells in different interrogation modes.To exert loads on the cells,these devices often comprise piezo-electric driven actuators that attach directly to the cell or move a structure on which cells are attached.Uniaxial and biaxial pullers,micropillars,and cantilever beams are examples of MEMS devices.In this review,the methodologies to analyze single cell activity under external loads using microfabricated devices will be examined.We will focus on the mechanical interrogation in three different regimes:compression,traction,and tension,and discuss different microfabricated platforms designed for these purposes.
