Biomicrofluidics
·
2015
·Vol. 9
·期 4
·
IF 3.357
Cai Longfei,Zhong Minghua,Li Huolin,Xu Chunxiu,Yuan Biyu
We describe a simple and cost-effective strategy for rapid fabrication of microfluidic paper-based analytical devices and valves by inkjet printing. NaOH aqueous solution was printed onto a hydrophobic filter paper, which was previously obtained by soaking in a trimethoxyoctadecylsilane-heptane solution, allowing selective wet etching of hydrophobic cellulose to create hydrophilic-hydrophobic contrast with a relatively good resolution. Hexadecyltrimethylammonium bromide (CTMAB)-ethanol solution was printed onto hydrophobic paper to fabricate temperature-controlled valves. At low temperature, CTMAB deposited on the paper is insoluble in aqueous fluid, thus the paper remains hydrophobic. At high temperature, CTMAB becomes soluble so the CTMAB-deposited channel becomes hydrophilic, allowing the wicking of aqueous solution through the valve. We believe that this strategy will be very attractive for the development of simple micro analytical devices for point-of-care applications, including diagnostic testing, food safety control, and environmental monitoring.
研究领域:
分析化学
·
生物医学工程
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DOI
PubMed
高影响因子
LAB ON A CHIP
·
2020
·Vol. 20
·期 7
·1227-1237
·
IF 6.774
Chang Chen,Dong Xu,Siwei Bai,Zhihang Yu,Yonggang Zhu,Xiao Xing,Huaying Chen
Inoculation of single cells into separate culture chambers is one of the key requirements in single-cell analysis. This paper reports an innovative microfluidic chip integrating two pneumatic microvalves to screen and print single cells onto a well plate. The upper and lower size limits of cells can be dynamically controlled by regulating the deformation of two adjacent microvalves. Numerical simulations were employed to systematically study the influence of membrane dimensions and pressure on the deflection of a valve. A mathematical model was then modified to predict the size of cells captured by a microvalve at various pressures. The membrane deflection was further studied using confocal imaging. The critical pressure trapping beads of various sizes was experimentally determined. These experiments validated the accuracy of both numerical simulations and the mathematical model. Furthermore, single beads and endothelial cells with the desired size range were screened using dual valves and printed onto well plates with 100% efficiency. Viability studies suggested that the screening process had no significant impact on cells. This device enables dynamic regulation of both the lower and the upper size limits of cells for printing. It has significant application potential in inoculating cells with desired sizes for various fields such as clonal expansion, monoclonality development and single-cell genomic studies.
研究领域:
生物工程
·
细胞生物学
·
微流体技术
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DOI
PubMed
高影响因子
CHROMATOGRAPHIA
·
2018
·Vol. 81
·期 7
·1103-1108
·
IF 1.401
Li Fangfang,Bao Yan,Yu Yuexue,Cui He,Fa Yun,Liu Huizhou
A valve-switching ion chromatography method coupled with conductivity and pulsed amperometric detection has been set up for the simultaneous determination of organic acids, inorganic anions and alditols in wine. The system, based on valve-switching technique, consisted of two pumps, two analytical columns and a trap column connected in series via one six-port valve. In addition, the optimal valve-switching time and chromatographic conditions were explored to obtain a good linearity, precision, accuracy, and sensitivity with a mean correlation coefficient of > 0.99, repeatability of 0.62–6.18% for eight replicates, and the average spiked recovery of 96.66%. The new method was successfully applied in the analysis of six kinds of wine from different regions.
研究领域:
分析化学
·
食品科学
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DOI
高影响因子
ACS Sensors
·
2018
·
IF 5.711
Jinglong Han,Anjin Qi,Junrui Zhou,Guan Wang,Bowei Li,Lingxin Chen
A novel strategy for fabricating the paper-based valves on microfluidic paper-based analytical devices (μPADs) was described to control fluid in a user-friendly way. Initial prototypes of 3D μPADs manipulate the spatial distribution of fluid within the device. The movable paper channel in a different layer could be achieved using the channel’s connection or disconnection to realize the valve function using plastic comb binding spines (PCBS). The entire valve manipulation process was similar to a desk calendar that can be flipped over and turned back. It is notable that this kind of PCBS valve can control a fluid in a simple and easy way without the timing setting or any trigger, and this advantage makes it user-friendly for untrained users to carry out the complex and high throughput operations. The reusable plastic comb binding spines greatly reduce the cost of fabricating paper-based valves. To evaluate the performance, the actual samples of Fe (II) and nitrite were successfully analyzed. We hope this method will introduce a new approach to fabrication of paper-based valves on μPADs in the future.
研究领域:
分析化学
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生物医学工程
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DOI
PubMed
高影响因子
MACROMOLECULAR MATERIALS AND ENGINEERING
·
2017
·Vol. 302
·期 11
·1700213
·
IF 2.863
Kai Hou,Weijie Wu,Mengge Xia,Meifang Zhu
Thermosensitive nanocomposite (NC) hydrogels are considered as a significant kind of intelligent material to be utilized as sensor, biomaterial, drug carrier, etc. Recently, preparation of remotely controlled NC hydrogel with high-performance attracts more and more concern. To produce facile remote-stimuli thermosensitive NC hydrogel, a novel near-infrared (NIR) laser switched CuS/clay/poly(OEGMA- co -MEO 2 MA) hydrogel is demonstrated, which can be precisely remote-stimulated by NIR irradiation based on the excellent NIR photothermal conversion property of CuS nanoparticle. The temperature change of hydrogel is related to the NIR intensity, CuS content, and crosslinking density. Moreover, the influences on dimensional variation of hydrogel on macroscale are systematically studied, and the hydrogel as smart liquid valve is further utilized which can be remotely controlled by NIR switch on/off successfully. Cyclic test illustrates that this novel CuS/clay/poly(OEGMA- co -MEO 2 MA) hydrogel exhibits stable cyclic volume transition property which has promising applications in the areas of sensors, valves, and intelligent switches.
研究领域:
材料科学
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生物医学工程
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产品关联
DOI
高影响因子
PLoS One
·
2015
·Vol. 10
·期 11
·e0141467
·
IF 3.234
Xiu-Zeng Bi,Wei-Hua Pan,Xin-Ping Yu,Zong-Ming Song,Zeng-Jin Ren,Min Sun,Cong-Hui Li,Kai-Hui Nan
This study was designed to investigate whether 5-fluorouracil (5-Fu)-polycaprolactone sustained-release film in Ahmed glaucoma valve implantation inhibits postoperative bleb scarring in rabbit eyes. Eighteen New Zealand white rabbits were randomly divided into three groups (A, B and C; n = 6 per group). Group A received combined 5-Fu-polycaprolactone sustained-release film application and Ahmed glaucoma valve implantation, group B received local infiltration of 5-Fu and Ahmed glaucoma valve implantation, and group C received Ahmed glaucoma valve implantation. Postoperative observations were made of the anterior segment, intraocular pressure, central anterior chamber depth, blebs, drainage tube, and accompanying ciliary body detachment. The pathology of the blebs and surrounding tissues were observed at month 3 postoperatively. We revealed that the 5-Fu-polycaprolactone sustained-release film maintained a release concentration range of 13.7 ± 0.12 to 37.41 ± 0.47 μg/ml over three months in vitro . Postoperatively, diffuse blebs with ridges were found in all eyes in group A, two blebs were observed in group B, and no bleb formation was present in group C. The postoperative central anterior chamber depth in group A was significantly less than that of the other two groups. The postoperative intraocular pressure of group A stabilized at 6.33–8.67 mmHg, whereas that of group C gradually remained at 7.55–10.02 mmHg. The histopathology showed that the fibrous tissue thickness of the blebs in group A was significantly thinner than that of the other groups. We conclude that the 5-Fu-polycaprolactone sustained-release film had a sustained drug release effect, which promoted the inhibition of bleb scarring after Ahmed glaucoma valve implantation.
研究领域:
眼科
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药理学
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生物医学工程
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DOI
PubMed
高影响因子
Advanced Composites and Hybrid Materials
·
2023
·Vol. 7
·期 1
·1-13
·
IF 20.1
Zhan Xue-Qing,Ran Zhuo-Qing,Bao Hong-Yu,Ye Qin,Chen Han,Fu Qiang,Ni Wang,Xu Jia-Min,Ma Ning,Tsai Fang-Chang
As a functional material, hydrogels hold promise in agricultural irrigation, potentially solving the problem of low utilization of irrigation water from the source. To enable more intuitive monitoring of soil moisture and achieve on-demand irrigation, a conductive hydrogel is being explored as a solenoid valve controller for intelligent irrigation. Here, intelligent hydrogel poly (acrylic acid-co–N-methylolacrylamide)/poly(3,4-ethylenedioxythiophene):polystyrene sulfonate, P(AA-co–N-MA)/PEDOT:PSS, with a dual network was synthesized under mild conditions through Na 2 SO 3 -APS (ammonium persulfate) initiation system. The structural design endows the hydrogel with excellent mechanical properties (elongation at break up to 2400%) and sensitive sensing performance (gauge factor, GF, is 8.14). The anti-fatigue properties of the hydrogel have proved that the material has good durability and good service life as a sensing material. In addition, by incorporating the relationship between moisture and conductivity, the hydrogel could be utilized as a controller for irrigation valves, enabling intelligent irrigation and effective conservation of water resources through soil moisture monitoring. Graphical abstract The intelligent hydrogel P(AA-co–N-MA)/PEDOT:PSS could be utilized as a controller of solenoid valve for irrigation through soil moisture monitoring.
研究领域:
材料科学
·
农业工程
·
环境科学
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产品关联
DOI
高影响因子
TALANTA
·
2011
·
IF 3.722
Yang Wang,Jie Tang,Xiaoyu Luo,Xiaoya Hu,Chun Yang,Qin Xu
In this work, a kojic acid electrochemical sensor, based on a non-covalent molecularly imprinted polymer (MIP) modified electrode, had been fabricated in the lab-on-valve system. The sensitive layer was synthesized by cyclic voltammetry using o -phenylenediamine as the functional monomer and kojic acid as the template. The template molecules were then removed from the modified electrode surface by washing with NaOH solution. Differential pulse voltammetry method using ferricyanide as probe was applied as the analytical technique, after extraction of kojic acid on the electrode. Chemical and flow parameters associated with the extraction process were investigated. The response recorded with the imprinted sensor exhibited a response in a range of 0.01–0.2 μmol L −1 with a detection limit of 3 nmol L −1 . The interference studies showed that the MIP modified electrode had excellent selectivity. Furthermore, the proposed MIP electrode exhibited good sensitivity and low sample/reagent consumption, and the sensor could be applied to the determination kojic acid in cosmetics samples.
研究领域:
分析化学
·
生物传感技术
✓ 已验证
DOI
高影响因子
ANALYTICA CHIMICA ACTA
·
2017
·
IF 4.95
Ya-Jie Zhang,Yi Cai,Yong-Liang Yu,Jian-Hua Wang
A miniature optical emission spectrometric (OES) system is developed by incorporating dielectric barrier discharge (DBD) microplasma as excitation source in a lab-on-valve (LOV) configuration for trace cadmium analysis. The entire system integrates bead injection (BI) sample pretreatment , post-column derivatization , in-situ nebulization and OES detection. Trace cadmium in sample solution is separated and preconcentrated by flowing through a 2-(5-Br-2-pyridylazo)-5-dethylaminophenol (5-Br-PADAP) loaded microcolumn in LOV, followed by elution with 20 μL of 0.1 M hydrochloric acid . The eluate after online derivatization with 5 μL of 0.2 M borate buffer solution containing 7.5% (v/v) ethanol is immediately transported into a pneumatic micronebulizer integrating DBD microplasma for cadmium excitation, and OES is recorded by using a charge coupled device (CCD) spectrometer. As a miniaturized analytical set-up, LOV provides an ideal sample-processing front-end with detection by DBD-OES, while introduction of DBD excitation source in LOV highly improves the analytical performances for trace metal species. With a sample volume of 1.0 mL, a detection limit of 0.06 μg L −1 and a linear range of 0.2–50 μg L −1 are achieved for cadmium, along with an enrichment factor of 38. The accuracy of the present system is confirmed by the determination of cadmium in certified reference materials, and further demonstrated by spiking recoveries of cadmium in real water samples.
研究领域:
分析化学
·
环境科学
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DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2016
·
IF 3.782
Xinyun Zhu,Cai-Qi Wang
A pH and redox dual-responsive nanovalve with a long stalk was introduced on the surface of hollow mesoporous silica nanoparticles (HMSs-S1) to achieve cargo size selectivity delivery. The responsive nanovalve was designed by constructing of a stalk/β-cyclodextrins (CDs) supramolecular complex, which is based on an acid-labile acetal group and the host–guest interactions between β-cyclodextrins and ferrocenyl moiety (Fc). With stimulation by different pH and H 2 O 2 , Rhodamine 6G showed well-responsive behavior. On account of the long stalks of nanovalve, doxorubicin hydrochloride and 5-fluorouracil with different sized cargos are encapsulated in HMSs-S1 to test its behavior of cargo size-selective delivery. Moreover the HMSs-S2 with a short stalk based on β-CDs/Fc inclusion complex is synthesized to load small sized 5-FU drug as contrast experiment. Compared with HMSs-S2, HMSs-S1 is compatible with larger drug molecules such as Rhodamine 6G (R6G) and doxorubicin hydrochloride (DOX), while small sized 5-fluorouracil (5-FU) is unable to be sealed by the nanovalve. Dual responsiveness and drug size selectivity make mechanized HMSs possess potential applications in drug delivery system.
研究领域:
材料科学
·
药物递送系统
·
纳米医学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2014
·
IF 5.9
Xuan Huang,Xuezhong Du
The synthesis and host–guest chemistry of pillararene (PA) derivatives are a hot research topic, and the applications of PAs in relevant research fields are essential to explore. Carboxylate-substituted pillar[6]arene (CPA[6])-valved mesoporous silica nanoparticles (MSNs) functionalized with dimethylbenzimidazolium (DMBI) and bipyridinium (BP) stalks were constructed, respectively, for multiresponsive controlled release. CPA[6] encircled the DMBI or BP stalks to develop supramolecular nanovalves for encapsulation of cargo within the MSN pores. The release of cargo was triggered by acidic pH or competitive binding for the dethreading of CPA[6] and the opening of the nanovalves; moreover, coordination chemistry is the first strategy to activate CPA nanovalves by metal chelating with the carboxylate groups of CPA for cargo release. The controlled release of the CPA[6]-valved MSN delivery systems can meet diverse requirements and has promising biological applications in targeted drug therapy.
研究领域:
材料科学
·
药物化学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
LAB ON A CHIP
·
2022
·Vol. 23
·期 2
·341-348
·
IF 7.517
Haiying Shen,Qiliang Li,Wenqi Song,Xingyu Jiang
On-chip valves can simplify a microfluidic chip and make it easy to operate. However, most on-chip valves already reported still need complicated manufacture and sophisticated supporting devices. In this work, we present a straightforward on-chip valve, which can be serially connected, to form an on-chip pump. The liquid can horizontally flow one way by the regular deformations of flexure strips in the two valves at both sides of the chamber under pressure changes in microchannels generated by repeated vertical movements of linear actuators. The volume of this system including the chip and the supporting device is 0.65 cubic decimeters, which is much smaller than that of reported systems with a volume of at least 12 cubic decimeters, and the weight of this system is only 0.56 kg, making it possible for point-of-care testing. We carry out an immunoassay of folic acid on chip, and the results show satisfactory reproducibility with acceptable coefficients of variation. We determine 163 clinical human serum samples for folic acid. Furthermore, we detect transferrin, cobalamin and folic acid simultaneously on one chip with both sandwich and competitive binding immunoassay methods. We anticipate that this on-chip valve and pump can be applied in immunoassays and other biosensing applications.
研究领域:
微流控
·
生物传感
·
即时诊断
·
分析化学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
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