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Vilimi Z, Pápay ZE, Basa B, Orekhova X, Kállai-Szabó N, Antal I. Microfluidic Rheology: An Innovative Method for Viscosity Measurement of Gels and Various Pharmaceuticals. Gels 2024; 10:464. [PMID: 39057487 PMCID: PMC11275386 DOI: 10.3390/gels10070464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2024] [Revised: 07/12/2024] [Accepted: 07/15/2024] [Indexed: 07/28/2024] Open
Abstract
Measuring the viscosity of pharmaceutical dosage forms is a crucial process. Viscosity provides information about the stability of the composition, the release rate of the drug, bioavailability, and, in the case of injectable drug formulations, even the force required for injection. However, measuring viscosity is a complex task with numerous challenges, especially for non-Newtonian materials, which include most pharmaceutical formulations, such as gels. Selecting the appropriate shear rate is critical. Since viscosity in many systems is highly temperature-dependent, stable temperature control is necessary during the measurement. Using microfluidics technology, it is now possible to perform rheological characterization and conduct fast and accurate measurements. Small sample volumes (even below 500 µL) are required, and viscosity determination can be carried out over a wide range of shear rates. Nevertheless, the pharmaceutical application of viscometers operating on the principle of microfluidics is not yet widespread. In our work, we compare the results of measurements taken with a microfluidic chip-based viscometer on different pharmaceutical forms (gels, solution) with those obtained using a traditional rotational viscometer, evaluating the relative advantages and disadvantages of the different methods. The microfluidics-based method enables time- and sample-efficient viscosity analysis of the examined pharmaceutical forms.
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Affiliation(s)
| | | | | | | | | | - István Antal
- Department of Pharmaceutics, Semmelweis University, Hőgyes E. Street 7-9, 1092 Budapest, Hungary; (Z.V.); (Z.E.P.); (B.B.)
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2
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Gong X, Guo R, Li X, Yang Y, Lin W. A red-emitting mitochondria targetable fluorescent probe for detecting viscosity in HeLa, zebrafish, and mice. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2024; 16:293-300. [PMID: 38115761 DOI: 10.1039/d3ay01488f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2023]
Abstract
Viscosity, an essential parameter of the cellular microenvironment, has the ability to indicate the condition of living cells. It is closely linked to numerous diseases like Alzheimer's disease, diabetes, and cardiovascular disorders. Therefore, it is necessary to design tools to effectively monitor viscosity changes, which could provide promising avenues for therapeutic interventions in these diseases. Herein, we report a novel mitochondria-targeting fluorescent probe GX-VS which was suitable for the detection of viscosity changes in vivo and in vitro. The probe GX-VS had many advantages such as long emission wavelength (650 nm), large Stokes shift (105 nm), significant fluorescence enhancement (59-fold), high sensitivity, good biocompatibility and so on. Biological experiments showed that the probe could target mitochondria and detect viscosity alterations in HeLa cells. Moreover, it has been successfully utilized to monitor viscosity changes induced by lipopolysaccharides (LPS) in inflammatory zebrafishes and living mice, which further underscored the capacity of GX-VS to explore fluctuations in viscosity within living organisms.
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Affiliation(s)
- Xi Gong
- Institute of Optical Materials and Chemical Biology, Guangxi Key Laboratory of Electrochemical Energy Materials, School of Chemistry and Chemical Engineering, Guangxi University, Nanning, Guangxi 530004, P. R. China.
| | - Rui Guo
- Institute of Optical Materials and Chemical Biology, Guangxi Key Laboratory of Electrochemical Energy Materials, School of Chemistry and Chemical Engineering, Guangxi University, Nanning, Guangxi 530004, P. R. China.
| | - Xiaoya Li
- Institute of Optical Materials and Chemical Biology, Guangxi Key Laboratory of Electrochemical Energy Materials, School of Chemistry and Chemical Engineering, Guangxi University, Nanning, Guangxi 530004, P. R. China.
| | - Yingjie Yang
- Institute of Optical Materials and Chemical Biology, Guangxi Key Laboratory of Electrochemical Energy Materials, School of Chemistry and Chemical Engineering, Guangxi University, Nanning, Guangxi 530004, P. R. China.
| | - Weiying Lin
- Institute of Optical Materials and Chemical Biology, Guangxi Key Laboratory of Electrochemical Energy Materials, School of Chemistry and Chemical Engineering, Guangxi University, Nanning, Guangxi 530004, P. R. China.
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3
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Torquato LMG, Hélaine N, Cui Y, O'Connell R, Gummel J, Robles ESJ, Jacob D, Cabral JT. Microfluidic in-line dynamic light scattering with a commercial fibre optic system. LAB ON A CHIP 2023; 23:2540-2552. [PMID: 37185587 DOI: 10.1039/d3lc00062a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
We report the coupling of dynamic light scattering (DLS) in microfluidics, using a contact-free fibre-optic system, enabling the under-flow characterisation of a range of solutions, dispersions, and structured fluids. The system is evaluated and validated with model systems, specifically micellar and (dilute) polymer solutions, and colloidal dispersions of different radii (∼1-100 nm). A systematic method of flow-DLS analysis is examined as a function of flow velocity (0-16 cm s-1), and considerations of the relative contribution of 'transit' and 'Brownian' terms enable the identification of regions where (i) a quiescent approximation suffices, (ii) the flow-DLS framework holds, as well as (iii) where deviations are found, until eventually (iv) the convection dominates. We investigate practically relevant, robust setups, namely that of a capillary connected to microdevice, as well as direct measurement on a glass microdevice, examining the role of capillary dimensions and challenges of optical alignment. We conclude with a demonstration of a continuous flow measurement of a binary surfactant/salt solution, whose micellar dimensions vary with composition, characterised with hundreds of data points (every ∼5 s) and adequate statistics, within a few minutes.
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Affiliation(s)
- Luis M G Torquato
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK.
| | - Nelson Hélaine
- CNRS UMR 5623, Laboratoire des IMRCP, Universite Paul Sabatier, Toulouse, France
| | - Yufan Cui
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK.
| | - Roisin O'Connell
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK.
| | - Jérémie Gummel
- Procter & Gamble, Brussels Innovation Centre, Temselaan 100, 1853 Strombeek-Bever, Belgium
| | - Eric S J Robles
- Procter & Gamble, Newcastle Innovation Centre, Newcastle upon Tyne NE12 9TS, UK
| | - David Jacob
- Cordouan Technologies, 11 Avenue Canteranne, 33600 Pessac, France
| | - João T Cabral
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK.
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4
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Salipante PF. Microfluidic techniques for mechanical measurements of biological samples. BIOPHYSICS REVIEWS 2023; 4:011303. [PMID: 38505816 PMCID: PMC10903441 DOI: 10.1063/5.0130762] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 12/30/2022] [Indexed: 03/21/2024]
Abstract
The use of microfluidics to make mechanical property measurements is increasingly common. Fabrication of microfluidic devices has enabled various types of flow control and sensor integration at micrometer length scales to interrogate biological materials. For rheological measurements of biofluids, the small length scales are well suited to reach high rates, and measurements can be made on droplet-sized samples. The control of flow fields, constrictions, and external fields can be used in microfluidics to make mechanical measurements of individual bioparticle properties, often at high sampling rates for high-throughput measurements. Microfluidics also enables the measurement of bio-surfaces, such as the elasticity and permeability properties of layers of cells cultured in microfluidic devices. Recent progress on these topics is reviewed, and future directions are discussed.
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Affiliation(s)
- Paul F. Salipante
- National Institute of Standards and Technology, Polymers and Complex Fluids Group, Gaithersburg, Maryland 20899, USA
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5
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Kang YJ. Biomechanical Assessment of Red Blood Cells in Pulsatile Blood Flows. MICROMACHINES 2023; 14:317. [PMID: 36838017 PMCID: PMC9958583 DOI: 10.3390/mi14020317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 01/24/2023] [Accepted: 01/24/2023] [Indexed: 06/18/2023]
Abstract
As rheological properties are substantially influenced by red blood cells (RBCs) and plasma, the separation of their individual contributions in blood is essential. The estimation of multiple rheological factors is a critical issue for effective early detection of diseases. In this study, three rheological properties (i.e., viscoelasticity, RBC aggregation, and blood junction pressure) are measured by analyzing the blood velocity and image intensity in a microfluidic device. Using a single syringe pump, the blood flow rate sets to a pulsatile flow pattern (Qb[t] = 1 + 0.5 sin(2πt/240) mL/h). Based on the discrete fluidic circuit model, the analytical formula of the time constant (λb) as viscoelasticity is derived and obtained at specific time intervals by analyzing the pulsatile blood velocity. To obtain RBC aggregation by reducing blood velocity substantially, an air compliance unit (ACU) is used to connect polyethylene tubing (i.d. = 250 µm, length = 150 mm) to the blood channel in parallel. The RBC aggregation index (AI) is obtained by analyzing the microscopic image intensity. The blood junction pressure (β) is obtained by integrating the blood velocity within the ACU. As a demonstration, the present method is then applied to detect either RBC-aggregated blood with different concentrations of dextran solution or hardened blood with thermally shocked RBCs. Thus, it can be concluded that the present method has the ability to consistently detect differences in diluent or RBCs in terms of three rheological properties.
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Affiliation(s)
- Yang Jun Kang
- Department of Mechanical Engineering, Chosun University, 309 Pilmun-daero, Dong-gu, Gwangju 61452, Republic of Korea
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6
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Chen H, Wang Y, Liu Y, Zou Q, Yu J. Sensing of Fluidic Features Using Colloidal Microswarms. ACS NANO 2022; 16:16281-16291. [PMID: 36197321 DOI: 10.1021/acsnano.2c05281] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Sensing of key parameters in fluidic environments has attracted extensive attention because the physical features of body fluids could be used for point-of-care disease diagnosis. Although various sensing methods have been investigated, effective sensing strategies of microenvironments remains a major challenge. In this paper, we propose an approach that can realize sensing of fluidic viscosity and ionic strength using microswarms formed by simple colloidal nanoparticles. The influences of fluidic ionic strength and viscosity on two swarm behaviors are analyzed (i.e., the spreading of circular vortex-like swarms and the elongation of elliptical swarms). The data models for quantifying the fluidic viscosity and ionic strength are obtained from experiments, and the fluidic features can be sensed successfully using the swarm behaviors. Furthermore, we demonstrate that the microswarms have the capability of passing through tortuous and narrow microchannels for sensing. Continuous sensing of different fluidic environments using swarms is also realized. Finally, the sensing of viscosity and ionic strength of porcine whole blood is presented, which also validates the feasibility of the sensing strategy.
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Affiliation(s)
- Hui Chen
- School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen518172, China
- Shenzhen Institute of Artificial Intelligence and Robotics for Society (AIRS), Shenzhen518129, China
| | - Yibin Wang
- School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen518172, China
- Shenzhen Institute of Artificial Intelligence and Robotics for Society (AIRS), Shenzhen518129, China
| | - Yuezhen Liu
- School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen518172, China
| | - Qian Zou
- School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen518172, China
| | - Jiangfan Yu
- School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen518172, China
- Shenzhen Institute of Artificial Intelligence and Robotics for Society (AIRS), Shenzhen518129, China
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7
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Pryazhnikov MI, Yakimov AS, Denisov IA, Pryazhnikov AI, Minakov AV, Belobrov PI. Fluid Viscosity Measurement by Means of Secondary Flow in a Curved Channel. MICROMACHINES 2022; 13:1452. [PMID: 36144075 PMCID: PMC9502554 DOI: 10.3390/mi13091452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 08/25/2022] [Accepted: 08/25/2022] [Indexed: 06/16/2023]
Abstract
This article presents a new approach to determining the viscosity of Newtonian fluid. The approach is based on the analysis of the secondary Dean flow in a curved channel. The study of the flow patterns of water and aqueous solutions of glycerin in a microfluidic chip with a U-microchannel was carried out. The advantages of a microfluidic viscometer based on a secondary Dean flow are its simplicity, quickness, and high accuracy in determining the viscosity coefficient of a liquid. A viscosity image in a short movie represents fluid properties. It is revealed that the viscosity coefficient can be determined by the dependence of the recirculation angle of the secondary Dean flow. The article provides a correlation between the Dean number and the flow recirculation angle. The results of the field experiment, presented in the article, correlate with the data obtained using computational fluid dynamics and allow for selecting parameters to create microfluidic viscometers with a U-shaped microchannel.
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Affiliation(s)
- Maxim I. Pryazhnikov
- Laboratory of Physical and Chemical Technologies for the Development of Hard-to-Recover Hydrocarbon Reserves, Siberian Federal University, 660041 Krasnoyarsk, Russia
- Laboratory of Heat Exchange Control in Phase and Chemical Transformations, Kutateladze Institute of Thermophysics, 630090 Novosibirsk, Russia
| | - Anton S. Yakimov
- Laboratory of Physical and Chemical Technologies for the Development of Hard-to-Recover Hydrocarbon Reserves, Siberian Federal University, 660041 Krasnoyarsk, Russia
| | - Ivan A. Denisov
- Laboratory of Physical and Chemical Technologies for the Development of Hard-to-Recover Hydrocarbon Reserves, Siberian Federal University, 660041 Krasnoyarsk, Russia
| | - Andrey I. Pryazhnikov
- Laboratory of Physical and Chemical Technologies for the Development of Hard-to-Recover Hydrocarbon Reserves, Siberian Federal University, 660041 Krasnoyarsk, Russia
| | - Andrey V. Minakov
- Laboratory of Physical and Chemical Technologies for the Development of Hard-to-Recover Hydrocarbon Reserves, Siberian Federal University, 660041 Krasnoyarsk, Russia
- Laboratory of Heat Exchange Control in Phase and Chemical Transformations, Kutateladze Institute of Thermophysics, 630090 Novosibirsk, Russia
| | - Peter I. Belobrov
- Department of Biophysics, Siberian Federal University, 660041 Krasnoyarsk, Russia
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Luo J, Hu B, Hu M, Wu W, Liu TL. An Energy‐Dense, Powerful, Robust Bipolar Zinc–Ferrocene Redox‐Flow Battery. Angew Chem Int Ed Engl 2022; 61:e202204030. [DOI: 10.1002/anie.202204030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Indexed: 11/10/2022]
Affiliation(s)
- Jian Luo
- Department of Chemistry and Biochemistry Utah State University 0300 Old Main Hill Logan UT 84322 USA
| | - Bo Hu
- Department of Chemistry and Biochemistry Utah State University 0300 Old Main Hill Logan UT 84322 USA
| | - Maowei Hu
- Department of Chemistry and Biochemistry Utah State University 0300 Old Main Hill Logan UT 84322 USA
| | - Wenda Wu
- Department of Chemistry and Biochemistry Utah State University 0300 Old Main Hill Logan UT 84322 USA
| | - T. Leo Liu
- Department of Chemistry and Biochemistry Utah State University 0300 Old Main Hill Logan UT 84322 USA
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9
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Luo J, Hu B, Hu M, Wu W, Liu TL. An Energy Dense, Powerful, Robust Bipolar Zinc‐Ferrocene Redox Flow Battery. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202204030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Jian Luo
- Utah State University Chemistry UNITED STATES
| | - Bo Hu
- Utah State University Chemistry UNITED STATES
| | - Maowei Hu
- Utah State University Chemistry UNITED STATES
| | - Wenda Wu
- Utah State University Chemistry UNITED STATES
| | - Tianbiao Leo Liu
- Utah State University Chemistry and Biochemistry 0300 Old Main Hill 84322 Logan UNITED STATES
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10
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Jang Y, Wee H, Oh J, Jung J. Single Microdroplet Breakup-Assisted Viscosity Measurement. MICROMACHINES 2022; 13:mi13040558. [PMID: 35457863 PMCID: PMC9032506 DOI: 10.3390/mi13040558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 03/25/2022] [Accepted: 03/29/2022] [Indexed: 12/04/2022]
Abstract
Recently, with the development of biomedical fields, the viscosity of prepolymer fluids, such as hydrogels, has played an important role in determining the mechanical properties of the extracellular matrix (ECM) or being closely related to cell viability in ECM. The technology for measuring viscosity is also developing. Here, we describe a method that can measure the viscosity of a fluid with trace amounts of prepolymers based on a simple flow-focused microdroplet generator. We also propose an equation that could predict the viscosity of a fluid. The viscosity of the prepolymer was predicted by measuring and calculating various lengths of the disperse phase at the cross junction of two continuous-phase channels and one disperse-phase channel. Bioprepolymer alginates and gelatin methacryloyl (GelMA) were used to measure the viscosity at different concentrations in a microdroplet generator. The break-up length of the dispersed phase at the cross junction of the channel gradually increased with increasing flow rate and viscosity. Additional viscosity analysis was performed to validate the standard viscosity calculation formula depending on the measured length. The viscosity formula derived based on the length of the alginate prepolymer was applied to GelMA. At a continuous phase flow rate of 400 uL/h, the empirical formula of alginate showed an error within about 2%, which was shown to predict the viscosity very well in the viscometer. Results of this study are expected to be very useful for hydrogel tuning in biomedical and tissue regeneration fields by providing a technology that can measure the dynamic viscosity of various prepolymers in a microchannel with small amounts of sample.
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Affiliation(s)
- Yeongseok Jang
- Department of Mechanical Design Engineering, Jeonbuk National University, Jeonju 54896, Korea;
| | - Hwabok Wee
- Department of Orthopaedics & Rehabilitation, College of Medicine, Pennsylvania State University, Hershey, PA 17033, USA;
| | - Jonghyun Oh
- Department of Nano-Bio Mechanical System Engineering, Jeonbuk National University, Jeonju 54896, Korea
- Correspondence: (J.O.); (J.J.)
| | - Jinmu Jung
- Department of Nano-Bio Mechanical System Engineering, Jeonbuk National University, Jeonju 54896, Korea
- Correspondence: (J.O.); (J.J.)
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Del Giudice F. A Review of Microfluidic Devices for Rheological Characterisation. MICROMACHINES 2022; 13:167. [PMID: 35208292 PMCID: PMC8877273 DOI: 10.3390/mi13020167] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 01/19/2022] [Accepted: 01/20/2022] [Indexed: 12/20/2022]
Abstract
The rheological characterisation of liquids finds application in several fields ranging from industrial production to the medical practice. Conventional rheometers are the gold standard for the rheological characterisation; however, they are affected by several limitations, including high costs, large volumes required and difficult integration to other systems. By contrast, microfluidic devices emerged as inexpensive platforms, requiring a little sample to operate and fashioning a very easy integration into other systems. Such advantages have prompted the development of microfluidic devices to measure rheological properties such as viscosity and longest relaxation time, using a finger-prick of volumes. This review highlights some of the microfluidic platforms introduced so far, describing their advantages and limitations, while also offering some prospective for future works.
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Affiliation(s)
- Francesco Del Giudice
- Department of Chemical Engineering, Faculty of Science and Engineering, School of Engineering and Applied Sciences, Swansea University, Swansea SA1 8EN, UK
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12
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Zhou Y, Liu C, Huang X, Qian X, Wang L, Lai P. Low-consumption photoacoustic method to measure liquid viscosity. BIOMEDICAL OPTICS EXPRESS 2021; 12:7139-7148. [PMID: 34858705 PMCID: PMC8606139 DOI: 10.1364/boe.444144] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 10/17/2021] [Accepted: 10/19/2021] [Indexed: 05/10/2023]
Abstract
Viscosity measurement is important in many areas of biomedicine and industry. Traditional viscometers are usually time-consuming and require huge sample volumes. Microfluidic viscometry may overcome the challenge of large sample consumption but suffers from a long process time and a complicated structure design and interaction. Here, we present a photoacoustic method that measures the liquid viscosity in a simple microfluidic-based tube. This new viscosity measurement method embraces fast detection speed and low fluid consumption, offering a new tool for efficient and convenient liquid viscosity measurement in a broad range of applications.
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Affiliation(s)
- Yingying Zhou
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong
- Department of Biomedical Engineering, Hong Kong Polytechnic University, Hong Kong
- The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen, China
- These authors contributed equally to this work
| | - Chao Liu
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong
- These authors contributed equally to this work
| | - Xiazi Huang
- Department of Biomedical Engineering, Hong Kong Polytechnic University, Hong Kong
- The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen, China
- These authors contributed equally to this work
| | - Xiang Qian
- Tsinghua-Shenzhen International Graduate School, Tsinghua University, Shenzhen, China
| | - Lidai Wang
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong
- City University of Hong Kong Shenzhen Research Institute, Shenzhen, China
| | - Puxiang Lai
- Department of Biomedical Engineering, Hong Kong Polytechnic University, Hong Kong
- The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen, China
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