An integrated flexible and reusable graphene field effect transistor nanosensor for monitoring glucose

Diabetes is a chronic metabolic disease that has effect on blood sugar level and affects millions of people.We present an integrated flexible and reusable graphene-based field effect transistor(GFET)nanosensor for the detection of glucose using pyrene-1-boronic acid(PBA)as the receptor.The nanosensor fabricated on the polyimide performs GFET-based rapid transduction of the glucose-PBA binding,thereby potentially allowing the detection of glucose that are sampled reliably from human bodily fluids(e.g.,sweat)in wearable sensing applications.Due to the reversible binding interaction between PBA and glucose,reusability of our nanosensor can be realized by exposing graphene surface to acidic solution.In characterizing the stability and reusability of the nanosensor for wearable applications,we investigated the effects of substrate bending,multiple reuse and long-time storage on the equilibrium dissociation constant between the PBA and glucose.Results show that bending,multiple reuse(over 10 times)and long-time storage has negligible effect on the sensing performance.The detection of glucose with a limit of detection(LOD)of 0.15 μM and a dynamic range of 0.05-100 μM,which covers the reference scope of physical examination or screening of diabetes.Hence,our flexible GFET nanosensor is promising for wearable and reusable biosensing applications.

蚕丝基葡萄糖传感器研究进展

葡萄糖传感器是糖尿病人监控血糖浓度的必备工具。基于柔性基底开发可用于实时监测的柔性葡萄糖传感器是近年来研究的热点,也是未来应用发展的重要方向。蚕丝具有优异的力学性能、生物相容性及生物可降解性,以蚕丝及蚕丝蛋白与导电活性物质复合开发的柔性葡萄糖传感器展现出优异的传感性能及出色的长期稳定性。本文通过对基于丝蛋白、丝纤维、蚕丝织物开发的蚕丝基葡萄糖传感器的研究进展进行综述,对比所开发的蚕丝基葡萄糖传感器的传感性能,分析其特点及作用机制,并展望蚕丝基葡萄糖传感器在柔性可穿戴传感器领域的发展前景。

可穿戴柔性连续动态血糖监测技术发展与挑战

糖尿病患者群体迫切追求能够精准控糖的高质量生活,迫切需要精准、舒适的血糖监测技术。然而传统指血法只能实现单次有创采血监测,无法满足需求。可穿戴柔性动态葡萄糖传感器作为下一代血糖监测技术的重要发展方向,在糖尿病管理方面拥有巨大的应用前景,是目前研究的热点。综述了近年来可穿戴柔性连续动态血糖监测技术的研究现状,探讨了可穿戴柔性血糖传感系统技术仍然面临的挑战与可能的突破方向,最后展望了可穿戴柔性血糖传感器商业化的趋势和未来的发展潜力。

Sensing nanomaterials of wearable glucose sensors

The metabolic disorder of glucose in human body will cause diseases such as diabetes and hyperglycemia.Hence the determination of glucose content is very important in clinic diagnosing.In recent years,researchers have proposed various non-invasive wearable sensors for rapid and real-time glucose monitoring from human body fluids.Unlike those reviews which discussed performances,detection environments or substrates of the wearable glucose sensor,this review focuses on the sensing nanomaterials since they are the key elements of most wearable glucose sensors.The sensing nanomaterials such as carbon,metals,and conductive polymers are summarized in detail.And also the structural characteristics of different sensing nanomaterials and the corresponding wearable glucose sensors are highlighted.Finally,we prospect the future development requirements of sensing nanomaterials for wearable glucose sensors.This review would give some insights to the further development of wearable glucose sensors and the modern medical treatment.

基于葡萄糖氧化酶的葡萄糖传感器的研究进展

综述了对葡萄糖具有良好的催化效应且被广泛用于葡萄糖传感器研发当中的葡萄糖氧化酶(GOx)在葡萄糖传感器酶电极中的固定化方法,并分析其对葡萄糖传感器性能的影响;根据连续监测形式将葡萄糖传感器划分成微创式、植入式和无创式,归纳总结了采用不同监测形式的葡萄糖传感器的最新研究进展;最后,对基于GOx的葡萄糖传感器在柔性可穿戴领域的发展前景进行了展望。

非图案化法制备柔性连续葡萄糖监测传感器

以聚多巴胺作为前驱体,在聚酰亚胺薄膜表面化学沉积一层牢固致密的金层,以该镀金薄膜两面的金层作为基体电极,在其中一面镀铂黑作为参比-对电极,在另一面依次电沉积铂黑层、电泳形成Nafion/碳纳米管网络层、电吸引形成葡萄糖氧化酶层构成工作电极,并整体涂覆聚氨酯外膜,制备了一种柔性葡萄糖传感器。考察了此传感器对葡萄糖的检测性能,以及各层表面形态结构对传感器性能的影响。传感器在0.3 V的工作电位下对葡萄糖的线性响应范围是2.0~32.0 mmol/L,响应灵敏度为25μA·(mmol/L)^(-1)·cm^(-2),检出限为0.05 mmol/L(S/N=3),且传感器有良好的长期稳定性和抗干扰性,可用于皮下连续血糖监测。

一种基于电沉积3D花状CoS在自支撑石墨烯胶带电极上的非酶葡萄糖传感器的研究与应用

本文将3D纳米结构花状CoS电沉积在石墨烯胶带电极(GTE)上,制备了一种对葡萄糖响应良好的电化学传感器。结构分析显示电沉积的CoS均匀地分散在了电极上。实验结果表明,制备的花状CoS/GTE葡萄糖传感器在0.025~1.0 mmol·L^(-1)显示出良好的线性关系,灵敏度为323.3μA·(mmol·L^(-1))^(-1)·cm^(-2),检出限为8.5μmol·L^(-1)(S/N=3),而且制备的传感器能够应用于血清葡萄糖的检测。这表明本文制备的传感器具有一定的应用潜力。

铜纳米颗粒修饰柔性石墨构建无酶葡萄糖传感器

柔性石墨片(FGS)具备优良的导电性与柔韧性,可作为葡萄糖传感器的自支撑载体,解决由于使用黏结剂降低传感器性能的问题。本文采用水热法,使用抗坏血酸还原硫酸铜,在FGS上复合铜纳米颗粒构建Cu/FGS自支撑无酶葡萄糖传感器,在线性范围0.1~3.4 mmol/L内具有较高的灵敏度7254.1μA·mM-1·cm-2(R2=0.9961),较低的检测限1.05μmol/L;在线性范围3.4~5.6 mmol/L灵敏度为3804.5μA·mM-1·cm-2(R2=0.9995)。此外,该电极还有较好的抗干扰性、重复性及稳定性。

枝晶状纳米铜修饰激光诱导石墨烯电化学传感器的制备及其在葡萄糖检测中的应用

本文以柔性聚酰亚胺(PI)薄膜为原料,采用激光雕刻方法构筑激光诱导石墨烯(LIG)三电极阵列。以此为基底,通过电沉积方法制备Ag/AgCl参比电极和枝晶状纳米Cu修饰工作电极,用于构建柔性非酶型葡萄糖电化学传感器。在0.1 mol/L NaOH和0.1 mol/L KCl的混合溶液中,施加0.5 V检测电位,其检测葡萄糖的灵敏度为1554.5μA/(mmol/L·cm2),线性范围为0.5~365.5μmol/L,检测限(S/N=3)为0.098μmol/L。该柔性传感器具有良好的重现性,其相对标准偏差(RSD,n=10)为2.96%;同时对多巴胺、抗坏血酸、尿酸、5-羟色胺和组胺等物质具有良好的抗干扰能力。

Au/rGO修饰的单壁碳纳米管柔性电极的制备及其在生物传感器中的应用

柔性可穿戴生物传感器对于慢性病人的健康监测具有重要意义。由单壁碳纳米管制成的巴基纸具备柔性好、导电性高及生物相容性强等特点,是制备柔性生物传感器电极的理想材料。由于单壁碳纳米管本身不具备催化活性,有必要使用活性材料对巴基纸进行修饰。本研究首次将单壁碳纳米管巴基纸与一步法还原的金纳米颗粒/还原氧化石墨烯溶液通过简单的真空抽滤形成双层结构的柔性电极。通过扫描电子显微镜、X射线衍射仪、紫外分光光度计、拉曼光谱仪对制备的柔性电极进行了形貌与结构的表征,结果表明金和氧化石墨烯被还原,其中金纳米颗粒的粒径大小为80~100nm左右,且密集地修饰在还原氧化石墨烯上。探究了该柔性电极对葡萄糖和H_(2)O_(2)的电化学行为,结果表明该电极对葡萄糖和H_(2)O_(2)表现出优异的电催化活性,在检测浓度范围内呈现良好的线性关系,其中H_(2)O_(2)检测灵敏度高达1533μA·(mmol/L)^(-1)cm^(-2),说明单壁碳纳米管巴基纸在柔性生物传感器领域具备较高的潜在价值。

水热生长镍钴硫化物在柔性无酶葡萄糖传感器中的应用

为开发快速、精确和稳定的葡萄糖检测技术,在碳布上利用水热法原位生长镍钴硫化物颗粒,制备镍钴硫化物@碳布自支撑柔性电极材料,并对该电极材料进行电化学测试。结果表明:镍钴硫化物@碳布电极对葡萄糖的灵敏度为3.934 A·(mol·L^(-1)·cm^(2))^(-1),检测线性范围为0.20μmol/L~2.50 mmol/L;对葡萄糖具有优异的选择性和稳定性。

MOF derived Co3O4/N-doped carbon nanotubes hybrids as efficient catalysts for sensitive detection of H2O2 and glucose

Developing enzyme-free sensors with high sensitivity and selectivity for H2O2 and glucose is highly desirable for biological science.Especially,it is attractive to exploit noble-metal-free nanomaterials with large surface area and good conductivity as highly active and selective catalysts for molecular detection in enzyme-free sensors.Herein,we successfully fabricate hollow frameworks of Co3O4/N-doped carbon nanotubes(Co3O4/NCNTs)hybrids by the pyrolysis of metal-organic frameworks followed by calcination in the air.The as-prepared novel hollow Co3O4/NCNTs hybrids exhibit excellent electrochemical performance for H2O2 reduction in neutral solutions and glucose oxidation in alkaline solutions.As sensor electrode,the Co3O4/NCNTs show excellent non-enzymatic sensing ability towards H2O2 response with a sensitivity of 87.40μA(mmol/L)^-1 cm^-2,a linear range of 5.00μmol/L-11.00 mmol/L,and a detection limitation of 1μmol/L in H2O2 detection,and a good glucose detection performance with 5μmol/L.These excellent electrochemical performances endow the hollow Co3O4/NCNTs as promising alternative to enzymes in the biological applications.

柔性全固态无创血糖传感器及3D打印模拟检测装置

基于反向离子电渗透原理,构建无创血糖检测体系。利用丝网印刷工艺制备柔性全固态电极,以普鲁士蓝为电子媒介体,用葡萄糖氧化酶修饰电极制得柔性葡萄糖生物传感器。对传感器的各项修饰条件进行优化,用计时电流法检验其性能,建立起体外葡萄糖溶液定量检测体系。结果表明:在低浓度区对葡萄糖的线性响应范围为0.5~6.5 mmol/L,相关系数(R)为0.993 3,检出限为0.1 mmol/L;高浓度区的线性响应范围为6.5~19.0 mmol/L,相关系数0.992 3。用3D打印制作模拟检测装置,在猪皮上模拟活体电渗透过程进行皮下葡萄糖定量检测。皮下葡萄糖浓度在2.0~14.0 mmol/L范围内,传感器的响应电流与其有较好的相关性(R=0.992 9),浓度范围满足日常血糖检测的需求。为进一步研制实用型无创血糖仪奠定了良好的基础。

柔性氧化亚铜基非酶葡萄糖传感器的制备及其传感行为

采用一步湿化学法制备立方氧化亚铜(Cu2O)晶体,通过磁控溅射技术在聚酰亚胺柔性衬底上沉积图案化的金薄膜,构建以Cu2O为工作电极、银/氯化银为参比电极,金为对电极的电化学三电极结构,并将该三电极结构作为非酶葡萄糖传感器。实验结果表明:该柔性传感器可以承受弯曲、折叠、扭曲等多种变形;对葡萄糖分子表现出良好的电催化活性,可检测的葡萄糖浓度线性范围为10.0μmol/L^7.0 mmol/L,灵敏度高达346.1μA·(mmol/L)^-1·cm^-2,检出限低达10.0μmol/L;对抗坏血酸、尿酸、多巴胺和其他离子等物质具有很强的抗干扰性,并且传感器在弯曲达到45°时依然能够正常工作,催化性能稳定。

利用碳纳米纤维/Pt纳米片构建柔性电极用于葡萄糖检测

糖尿病是一种以高血糖为特征的代谢性疾病,严重威胁人类健康。血糖指标的监测在糖尿病的预防、诊断及治疗中发挥着重要作用。以聚丙烯腈为碳源,通过静电纺丝与热处理工艺制备了柔性碳纳米纤维膜,并利用恒电位电沉积法在自支撑碳纳米纤维膜上负载Pt纳米片构建柔性无酶葡萄糖传感器。结果表明,碳纳米纤维表面光滑,Pt纳米片逐渐生长并填满纳米纤维间隙,单个纳米片长100~200 nm,宽约100 nm。构建的柔性无酶葡萄糖传感器对葡萄糖的线性检测范围为7.5~87.5 mmol/L,灵敏度为6.41μA·(mmol/L)^(-1)·cm^(-2),最低检测限为14.04μmol/L,同时传感器表现出良好的抗干扰性、重复性和稳定性。该柔性电极材料制备方法简单,结合柔性电极和无酶传感器的优势,避免传统酶传感器重复性、稳定性及抗干扰性能差的问题,为柔性葡萄糖传感器的构建提供了可能。

基于直接电子转移的柔性纤维葡萄糖传感器

酶基电化学葡萄糖传感器具有优异的选择性和灵敏度,基于直接电子转移原理的第三代传感器有望解决第一、二代传感器所面临的易受氧气浓度干扰、电子介体不稳定等问题.因此,本研究基于聚3,4-乙烯二氧噻吩:聚苯乙烯磺酸盐(PEDOT:PSS)和葡萄糖脱氢酶(GDH)双组分开发了柔性纤维第三代葡萄糖传感器.该纤维传感器在10~500μmol/L范围内具有良好的线性(R^(2)=0.9968),灵敏度可达62.53μA/(mmol·L^(-1)·cm^(2)),且不受氧气影响.纤维传感器还具有良好的柔性和可编织性,将其集成到织物中,实现了人在运动时汗液中葡萄糖的连续实时监测,为制备满足可穿戴需求的第三代葡萄糖传感器提供了新思路.

A toolkit of thread-based microfluidics,sensors,and electronics for 3D tissue embedding for medical diagnostics

Threads,traditionally used in the apparel industry,have recently emerged as a promising material for the creation of tissue constructs and biomedical implants for organ replacement and repair.The wicking property and flexibility of threads also make them promising candidates for the creation of three-dimensional(3D)microfluidic circuits.In this paper,we report on thread-based microfluidic networks that interface intimately with biological tissues in three dimensions.We have also developed a suite of physical and chemical sensors integrated with microfluidic networks to monitor physiochemical tissue properties,all made from thread,for direct integration with tissues toward the realization of a thread-based diagnostic device(TDD)platform.The physical and chemical sensors are fabricated from nanomaterial-infused conductive threads and are connected to electronic circuitry using thread-based flexible interconnects for readout,signal conditioning,and wireless transmission.To demonstrate the suite of integrated sensors,we utilized TDD platforms to measure strain,as well as gastric and subcutaneous pH in vitro and in vivo.