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Das D, Huang SH, Weng CL, Yu CH, Hsu CK, Lee YC, Cheng HC, Chuang HS. Detachable acoustofluidic droplet-sorter. Anal Chim Acta 2024; 1321:343043. [PMID: 39155105 DOI: 10.1016/j.aca.2024.343043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2024] [Revised: 07/27/2024] [Accepted: 07/30/2024] [Indexed: 08/20/2024]
Abstract
BACKGROUND Cell sorting is crucial in isolating specific cell populations. It enables detailed analysis of their functions and characteristics and plays a vital role in disease diagnosis, drug discovery, and regenerative medicine. Fluorescence-activated cell sorting (FACS) is considered the gold standard for high-speed single-cell sorting. However, its high cost, complex instrumentation, and lack of portability are significant limitations. Additionally, the high pressure and electric fields used in FACS can harm cell integrity. In this work, an acoustofluidic device was developed in combination with surface acoustic wave (SAW) and droplet microfluidics to isolate single-cell droplets with high purity while maintaining high cell viability. RESULT Human embryonic kidney cells, transfected with fluorescent reporter plasmids, were used to demonstrate the targeted droplet sorting containing single cells. The acoustofluidic sorter achieved a recovery rate of 81 % and an accuracy rate higher than 97 %. The device maintained a cell viability rate of 95 % and demonstrated repeatability over 20 consecutive trials without compromising efficiency, thus underscoring its reliability. Thermal image analysis revealed that the temperature of the interdigital transducer (IDT) during SAW operation remained within the permissible range for maintaining cell viability. SIGNIFICANCE The findings highlighted the sensitivity and effectiveness of the developed acoustofluidic device as a tool for single-cell sorting. The detachable microfluidic chip design enables the reusability of the expensive IDT, making it cost-effective and reducing the risk of cross-contamination between different biological samples. The results underscore its capability to accurately isolate individual cells on the basis of specific criteria, showcasing its potential to advance research and clinical applications requiring precise cell sorting methodologies.
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Affiliation(s)
- Dhrubajyoti Das
- Department of Biomedical Engineering, National Cheng Kung University, Tainan, 701, Taiwan
| | - Shih-Hong Huang
- Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan, 701, Taiwan; Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, 701, Taiwan
| | - Choa-Li Weng
- Department of Mechanical Engineering, National Cheng Kung University, Tainan, 701, Taiwan
| | - Chien-Hung Yu
- Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan, 701, Taiwan; Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, 701, Taiwan
| | - Chao-Kai Hsu
- Department of Dermatology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, 701, Taiwan
| | - Yung-Chun Lee
- Department of Mechanical Engineering, National Cheng Kung University, Tainan, 701, Taiwan
| | - Hui-Ching Cheng
- Department of Dermatology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, 701, Taiwan
| | - Han-Sheng Chuang
- Department of Biomedical Engineering, National Cheng Kung University, Tainan, 701, Taiwan; Medical Device Innovation Center, National Cheng Kung University, Tainan, 701, Taiwan.
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Gai C, Ma Q, Ning J, Ding Y, Lei Y, Li H, Guo C, Hu H. Development of Highly Efficient Lamb Wave Transducers toward Dual-Surface Simultaneous Atomization. SENSORS (BASEL, SWITZERLAND) 2024; 24:5607. [PMID: 39275518 DOI: 10.3390/s24175607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2024] [Revised: 08/19/2024] [Accepted: 08/28/2024] [Indexed: 09/16/2024]
Abstract
Highly efficient surface acoustic wave (SAW) transducers offer significant advantages for microfluidic atomization. Aiming at highly efficient atomization, we innovatively accomplish dual-surface simultaneous atomization by strategically positioning the liquid supply outside the IDT aperture edge. Initially, we optimize Lamb wave transducers and specifically investigate their performance based on the ratio of substrate thickness to acoustic wavelength. When this ratio h/λ is approximately 1.25, the electromechanical coupling coefficient of A0-mode Lamb waves can reach around 5.5% for 128° Y-X LiNbO3. We then study the mechanism of droplet atomization with the liquid supply positioned outside the IDT aperture edge. Experimental results demonstrate that optimized Lamb wave transducers exhibit clear dual-surface simultaneous atomization. These transducers provide equivalent amplitude acoustic wave vibrations on both surfaces, causing the liquid thin film to accumulate at the edges of the dual-surface and form a continuous mist.
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Affiliation(s)
- Chenhui Gai
- School of Mechanical Engineering and Automation, Harbin Institute of Technology, Shenzhen 518055, China
| | - Qinghe Ma
- School of Mechanical Engineering and Automation, Harbin Institute of Technology, Shenzhen 518055, China
| | - Jia Ning
- School of Mechanical Engineering and Automation, Harbin Institute of Technology, Shenzhen 518055, China
| | - Yizhan Ding
- School of Mechanical Engineering and Automation, Harbin Institute of Technology, Shenzhen 518055, China
| | - Yulin Lei
- School of Mechanical Engineering and Automation, Harbin Institute of Technology, Shenzhen 518055, China
| | - Honggeng Li
- School of Advanced Engineering, Great Bay University, Dongguan 523000, China
| | - Chunhua Guo
- CNNC Shenzhen Group Co., Ltd., Shenzhen 523000, China
| | - Hong Hu
- School of Mechanical Engineering and Automation, Harbin Institute of Technology, Shenzhen 518055, China
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3
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Wei W, Wang Z, Wang B, He X, Wang Y, Bai Y, Yang Q, Pang W, Duan X. Acoustofluidic manipulation for submicron to nanoparticles. Electrophoresis 2024. [PMID: 38794970 DOI: 10.1002/elps.202400062] [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: 03/29/2024] [Revised: 04/25/2024] [Accepted: 04/29/2024] [Indexed: 05/27/2024]
Abstract
Particles, ranging from submicron to nanometer scale, can be broadly categorized into biological and non-biological types. Submicron-to-nanoscale bioparticles include various bacteria, viruses, liposomes, and exosomes. Non-biological particles cover various inorganic, metallic, and carbon-based particles. The effective manipulation of these submicron to nanoparticles, including their separation, sorting, enrichment, assembly, trapping, and transport, is a fundamental requirement for different applications. Acoustofluidics, owing to their distinct advantages, have emerged as a potent tool for nanoparticle manipulation over the past decade. Although recent literature reviews have encapsulated the evolution of acoustofluidic technology, there is a paucity of reports specifically addressing the acoustical manipulation of submicron to nanoparticles. This article endeavors to provide a comprehensive study of this topic, delving into the principles, apparatus, and merits of acoustofluidic manipulation of submicron to nanoparticles, and discussing the state-of-the-art developments in this technology. The discourse commences with an introduction to the fundamental theory of acoustofluidic control and the forces involved in nanoparticle manipulation. Subsequently, the working mechanism of acoustofluidic manipulation of submicron to nanoparticles is dissected into two parts, dominated by the acoustic wave field and the acoustic streaming field. A critical analysis of the advantages and limitations of different acoustofluidic platforms in nanoparticles control is presented. The article concludes with a summary of the challenges acoustofluidics face in the realm of nanoparticle manipulation and analysis, and a forecast of future development prospects.
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Affiliation(s)
- Wei Wei
- State Key Laboratory of Precision Measuring Technology & Instruments, Tianjin University, Tianjin, P. R. China
| | - Zhaoxun Wang
- State Key Laboratory of Precision Measuring Technology & Instruments, Tianjin University, Tianjin, P. R. China
| | - Bingnan Wang
- State Key Laboratory of Precision Measuring Technology & Instruments, Tianjin University, Tianjin, P. R. China
| | - Xinyuan He
- State Key Laboratory of Precision Measuring Technology & Instruments, Tianjin University, Tianjin, P. R. China
| | - Yaping Wang
- State Key Laboratory of Precision Measuring Technology & Instruments, Tianjin University, Tianjin, P. R. China
| | - Yang Bai
- State Key Laboratory of Precision Measuring Technology & Instruments, Tianjin University, Tianjin, P. R. China
| | - Qingrui Yang
- State Key Laboratory of Precision Measuring Technology & Instruments, Tianjin University, Tianjin, P. R. China
| | - Wei Pang
- State Key Laboratory of Precision Measuring Technology & Instruments, Tianjin University, Tianjin, P. R. China
| | - Xuexin Duan
- State Key Laboratory of Precision Measuring Technology & Instruments, Tianjin University, Tianjin, P. R. China
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Kolesnik K, Rajagopal V, Collins DJ. Optimizing coupling layer and superstrate thickness in attachable acoustofluidic devices. ULTRASONICS 2024; 137:107202. [PMID: 37979521 DOI: 10.1016/j.ultras.2023.107202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 10/20/2023] [Accepted: 11/11/2023] [Indexed: 11/20/2023]
Abstract
Superstrate-based acoustofluidic devices, where the fluidic elements are reversibly coupled to a transducer rather than bonded to it, offer advantages for cost, interchangeability and preventing contamination between samples. A variety of coupling materials can be used to transmit acoustic energies into attachable superstrates, though the dimensions and material composition of the system elements are not typically optimized. This work analyzes these coupling layers for bulk wavefront transmission, including water, ultrasound gel and polydimethylsiloxane (PDMS), as well as the material makeup and thickness of the superstrate component, which is commonly comprised of glass, quartz or silicon. Our results highlight the importance of coupling layer and superstrate dimensions, identifying frequencies and component thicknesses that maximize transmission efficiency. Our results indicate that superstrate thicknesses 0.55 times the acoustic wavelength result in maximal acoustic coupling. While various coupling layers and superstrate materials are capable of similar acoustic energy transmission, the inherent dimensional stability of the PDMS coupling layers, somewhat less common in superstrate work compared to liquid-based agents, presents advantages for practically maximizing acoustic efficiency.
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Affiliation(s)
- Kirill Kolesnik
- Department of Biomedical Engineering, University of Melbourne, Melbourne, VIC 3010, Australia
| | - Vijay Rajagopal
- Department of Biomedical Engineering, University of Melbourne, Melbourne, VIC 3010, Australia
| | - David J Collins
- Department of Biomedical Engineering, University of Melbourne, Melbourne, VIC 3010, Australia; The Graeme Clark Institute, The University of Melbourne, Parkville, VIC 3010, Australia.
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Hossein F, Angeli P. A review of acoustofluidic separation of bioparticles. Biophys Rev 2023; 15:2005-2025. [PMID: 38192342 PMCID: PMC10771489 DOI: 10.1007/s12551-023-01112-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Accepted: 08/09/2023] [Indexed: 01/08/2024] Open
Abstract
Acoustofluidics is an emerging interdisciplinary research field that involves the integration of acoustics and microfluidics to address challenges in various scientific areas. This technology has proven to be a powerful tool for separating biological targets from complex fluids due to its label-free, biocompatible, and contact-free nature. Considering a careful designing process and tuning the acoustic field particles can be separated with high yield. Recently the advancement of acoustofluidics led to the development of point-of-care devices for separations of micro particles which address many of the limitations of conventional separation tools. This review article discusses the working principles and different approaches of acoustofluidic separation and provides a synopsis of its traditional and emerging applications, including the theory and mechanism of acoustofluidic separation, blood component separation, cell washing, fluorescence-activated cell sorting, circulating tumor cell isolation, and exosome isolation. The technology offers great potential for solving clinical problems and advancing scientific research.
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Affiliation(s)
- Fria Hossein
- Department of Chemical Engineering, University College London, Torrington Place, WC1E 7JE, London, UK
| | - Panagiota Angeli
- Department of Chemical Engineering, University College London, Torrington Place, WC1E 7JE, London, UK
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Mezzanzanica G, Français O, Mariani S. Surface Acoustic Wave-Based Microfluidic Device for Microparticles Manipulation: Effects of Microchannel Elasticity on the Device Performance. MICROMACHINES 2023; 14:1799. [PMID: 37763962 PMCID: PMC10537826 DOI: 10.3390/mi14091799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 09/18/2023] [Accepted: 09/19/2023] [Indexed: 09/29/2023]
Abstract
Size sorting, line focusing, and isolation of microparticles or cells are fundamental ingredients in the improvement of disease diagnostic tools adopted in biology and biomedicine. Microfluidic devices are exploited as a solution to transport and manipulate (bio)particles via a liquid flow. Use of acoustic waves traveling through the fluid provides non-contact solutions to the handling goal, by exploiting the acoustophoretic phenomenon. In this paper, a finite element model of a microfluidic surface acoustic wave-based device for the manipulation of microparticles is reported. Counter-propagating waves are designed to interfere inside a PDMS microchannel and generate a standing surface acoustic wave which is transmitted to the fluid as a standing pressure field. A model of the cross-section of the device is considered to perform a sensitivity analysis of such a standing pressure field to uncertainties related to the geometry of the microchannel, especially in terms of thickness and width of the fluid domain. To also assess the effects caused by possible secondary waves traveling in the microchannel, the PDMS is modeled as an elastic solid material. Remarkable effects and possible issues in microparticle actuation, as related to the size of the microchannel, are discussed by way of exemplary results.
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Affiliation(s)
- Gianluca Mezzanzanica
- Department of Civil and Environmental Engineering, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milan, Italy;
| | - Olivier Français
- Electronics, Communication systems and Microsystems (ESYCOM), Université Gustave Eiffel, National Centre of Scientific Research (CNRS), F-77454 Marne-la-Vallée, France;
| | - Stefano Mariani
- Department of Civil and Environmental Engineering, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milan, Italy;
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Wei W, Wang Y, Wang Z, Duan X. Microscale acoustic streaming for biomedical and bioanalytical applications. Trends Analyt Chem 2023. [DOI: 10.1016/j.trac.2023.116958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Mokhtare A, Davaji B, Xie P, Yaghoobi M, Rosenwaks Z, Lal A, Palermo G, Abbaspourrad A. Non-contact ultrasound oocyte denudation. LAB ON A CHIP 2022; 22:777-792. [PMID: 35075469 DOI: 10.1039/d1lc00715g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Cumulus removal (CR) is a central prerequisite step for many protocols involved in the assisted reproductive technology (ART) such as intracytoplasmic sperm injection (ICSI) and preimplantation genetic testing (PGT). The most prevalent CR technique is based upon laborious manual pipetting, which suffers from inter-operator variability and therefore a lack of standardization. Automating CR procedures would alleviate many of these challenges, improving the odds of a successful ART or PGT outcome. In this study, a chip-scale ultrasonic device consisting of four interdigitated transducers (IDT) on a lithium niobate substrate has been engineered to deliver megahertz (MHz) range ultrasound to perform denudation. The acoustic streaming and acoustic radiation force agitate COCs inside a microwell placed on top of the LiNbO3 substrate to remove the cumulus cells from the oocytes. This paper demonstrates the capability and safety of the denudation procedure utilizing surface acoustic wave (SAW), achieving automation of this delicate manual procedure and paving the steps toward improved and standardized oocyte manipulation.
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Affiliation(s)
- Amir Mokhtare
- Department of Food Science, Cornell University, Stocking Hall, Ithaca, NY, 14853, USA.
| | - Benyamin Davaji
- School of Electrical and Computer Engineering, Cornell University, Ithaca, NY, USA
| | - Philip Xie
- The Ronald O. Perelman and Claudia Cohen Center for Reproductive Medicine, Weill Cornell Medicine, New York, NY, 10021, USA
| | - Mohammad Yaghoobi
- Department of Food Science, Cornell University, Stocking Hall, Ithaca, NY, 14853, USA.
| | - Zev Rosenwaks
- The Ronald O. Perelman and Claudia Cohen Center for Reproductive Medicine, Weill Cornell Medicine, New York, NY, 10021, USA
| | - Amit Lal
- School of Electrical and Computer Engineering, Cornell University, Ithaca, NY, USA
| | - Gianpiero Palermo
- The Ronald O. Perelman and Claudia Cohen Center for Reproductive Medicine, Weill Cornell Medicine, New York, NY, 10021, USA
| | - Alireza Abbaspourrad
- Department of Food Science, Cornell University, Stocking Hall, Ithaca, NY, 14853, USA.
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Qian J, Begum H, Lee JEY. Acoustofluidic localization of sparse particles on a piezoelectric resonant sensor for nanogram-scale mass measurements. MICROSYSTEMS & NANOENGINEERING 2021; 7:61. [PMID: 34567773 PMCID: PMC8433202 DOI: 10.1038/s41378-021-00288-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 06/22/2021] [Accepted: 06/26/2021] [Indexed: 05/24/2023]
Abstract
The ability to weigh microsubstances present in low concentrations is an important tool for environmental monitoring and chemical analysis. For instance, developing a rapid analysis platform that identifies the material type of microplastics in seawater would help evaluate the potential toxicity to marine organisms. In this study, we demonstrate the integration of two different techniques that bring together the functions of sparse particle localization and miniaturized mass sensing on a microelectromechanical system (MEMS) chip for enhanced detection and minimization of negative measurements. The droplet sample for analysis is loaded onto the MEMS chip containing a resonant mass sensor. Through the coupling of a surface acoustic wave (SAW) from a SAW transducer into the chip, the initially dispersed microparticles in the droplet are localized over the detection area of the MEMS sensor, which is only 200 µm wide. The accreted mass of the particles is then calibrated against the resulting shift in resonant frequency of the sensor. The SAW device and MEMS chip are detachable after use, allowing the reuse of the SAW device part of the setup instead of the disposal of both parts. Our platform maintains the strengths of noncontact and label-free dual-chip acoustofluidic devices, demonstrating for the first time an integrated microparticle manipulation and real-time mass measurement platform useful for the analysis of sparse microsubstances.
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Affiliation(s)
- Jingui Qian
- Department of Electrical Engineering, City University of Hong Kong, Kowloon, Hong Kong SAR China
| | - Habiba Begum
- Department of Electrical Engineering, City University of Hong Kong, Kowloon, Hong Kong SAR China
| | - Joshua E.-Y. Lee
- Department of Electrical Engineering, City University of Hong Kong, Kowloon, Hong Kong SAR China
- State Key Laboratory of Terahertz and Millimeter Waves, City University of Hong Kong, Kowloon, Hong Kong SAR China
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Qian J, Huang W, Yang R, Lam RHW, Lee JEY. Low-cost laser-cut patterned chips for acoustic concentration of micro- to nanoparticles and cells by operating over a wide frequency range. Analyst 2021; 146:3280-3288. [PMID: 33999056 DOI: 10.1039/d1an00197c] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Acoustofluidic platforms for cell manipulation benefit from being contactless and label-free at potentially low cost. Particle concentration in a droplet relies on augmenting spatial asymmetry in the acoustic field, which is difficult to reproduce reliably. Etching periodic patterns into a chip to create acoustic band gaps is an attractive approach to spatially modify the acoustic field. However, the sensitivity of acoustic band structures to geometrical tolerances requires the use of costly microfabrication processes. In this work, we demonstrate particle concentration across a range of periodic structure patterns fabricated with a laser-cutting tool, suitable for low-cost and low-volume rapid prototyping. The relaxation on precision is underscored by experimental results of equally efficient particle concentration outside band gaps and even in their absence, allowing operation over a range of frequencies independent of acoustic band gaps. These results are significant by indicating the potential of extending the proposed method from the microscale (e.g. tumor cells) to the nanoscale (e.g. bacteria) by scaling up the frequency without being limited by fabrication capabilities. We demonstrate the device's high degree of biocompatibility to illustrate the method's applicability in the biomedical field for applications such as basic biochemical analysis and in vitro diagnosis.
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Affiliation(s)
- Jingui Qian
- Department of Electrical Engineering, City University of Hong Kong, Hong Kong.
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Wong KS, Lim WTH, Ooi CW, Yeo LY, Tan MK. In situ generation of plasma-activated aerosols via surface acoustic wave nebulization for portable spray-based surface bacterial inactivation. LAB ON A CHIP 2020; 20:1856-1868. [PMID: 32342089 DOI: 10.1039/d0lc00001a] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The presence of reactive species in plasma-activated water is known to induce oxidative stresses in bacterial species, which can result in their inactivation. By integrating a microfludic chipscale nebulizer driven by surface acoustic waves (SAWs) with a low-temperature atmospheric plasma source, we demonstrate an efficient technique for in situ production and application of plasma-activated aerosols for surface disinfection. Unlike bulk conventional systems wherein the water is separately batch-treated within a container, we show in this work the first demonstration of continuous plasma-treatment of water as it is transported through a paper strip from a reservoir onto the chipscale SAW device. The significantly larger surface area to volume ratio of the water within the paper strip leads to a significant reduction in the duration of the plasma-treatment, while maintaining the concentration of the reactive species. The subsequent nebulization of the plasma-activated water by the SAW then allows the generation of plasma-activated aerosols, which can be directly sprayed onto the contaminated surface, therefore eliminating the storage of the plasma-activated water and hence circumventing the typical limitation in conventional systems wherein the concentration of the reactive species diminishes over time during storage, resulting in a reduction in the efficacy of bacterial inactivation. In particular, we show up to 96% reduction in Escherichia coli colonies through direct spraying with the plasma-activated aerosols. This novel, low-cost, portable and energy-efficient hybrid system necessitates only minimal maintenance as it only requires the supply of tap water and battery power for operation, and is thus suitable for decontamination in home environments.
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Affiliation(s)
- Kiing S Wong
- School of Engineering, Monash University Malaysia, 47500 Bandar Sunway, Selangor, Malaysia.
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