1
|
Shahemi NH, Liza S, Sawae Y, Morita T, Shinmori H, Yaakob Y. Effects of surface wettability and thermal conductivity on the wear performance of ultrahigh molecular weight polyethylene/graphite and ultrahigh molecular weight polyethylene/graphene oxide composites. POLYM ADVAN TECHNOL 2022. [DOI: 10.1002/pat.5651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Nur Hidayah Shahemi
- TriPreM i‐Kohza, Department of Mechanical Precision Engineering, Malaysia‐Japan International Institute Technology Universiti Teknologi Malaysia Kuala Lumpur Malaysia
| | - Shahira Liza
- TriPreM i‐Kohza, Department of Mechanical Precision Engineering, Malaysia‐Japan International Institute Technology Universiti Teknologi Malaysia Kuala Lumpur Malaysia
| | - Yoshinori Sawae
- Machine Elements and Design Engineering Laboratory, Department of Mechanical Engineering, Faculty of Engineering Kyushu University Fukuoka Japan
| | - Takehiro Morita
- Machine Elements and Design Engineering Laboratory, Department of Mechanical Engineering, Faculty of Engineering Kyushu University Fukuoka Japan
| | - Hironori Shinmori
- Machine Elements and Design Engineering Laboratory, Department of Mechanical Engineering, Faculty of Engineering Kyushu University Fukuoka Japan
| | - Yazid Yaakob
- Department of Physics, Faculty of Science Universiti Putra Malaysia Serdang Malaysia
| |
Collapse
|
2
|
Wongtawan T, Dararatana N, Thongkittidilok C, Kornmatitsuk S, Oonkhanond B. Enrichment of bovine X-sperm using microfluidic dielectrophoretic chip: A proof-of- concept study. Heliyon 2020; 6:e05483. [PMID: 33241151 PMCID: PMC7672294 DOI: 10.1016/j.heliyon.2020.e05483] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 09/07/2020] [Accepted: 11/06/2020] [Indexed: 11/30/2022] Open
Abstract
The microfluidic dielectrophoretic (MF-DEP) chip is a new, economical and readily-available technology that might be used to enrich X-sperm for increasing female offspring in dairy farms. In this study, we sought to develop an MF-DEP chip to enrich X bovine sperm. The MF-DEP chip was composed of an electrode attached to a glass slide and a microchannel made from polydimethylsiloxane. Sex-sorted sperm from flow cytometry were used to identify optimal electric field conditions while unsorted sperm were later tested for sorting efficiency. The results show that during dielectrophoresis some sperm attached to the electrode (called positive DEP; pDEP) whereas other moved away from the electrode (called negative DEP; nDEP). X and Y-sperm responded to dielectrophoresis differently depending on various factors such as buffers, voltages, and frequencies. We found that the condition 4 V 1 MHz significantly reduced (P < 0.05) the percentage of Y-sperm to nearly 30 and therefore enriched X-sperm. The sorting efficiency was dependent on buffer, bull, sorting cycle, flow rate, electrical voltage, and frequency. Notably, the best sorting buffer found in this experiment was the conducting buffer, but this buffer significantly reduced sperm viability and motility. Other sperm-friendly buffers, TRIS and mHTF, were also used, but could not enrich X-sperm. In conclusion, this is a proof of concept that the MF-DEP chip can be effectively used to enrich bovine X-sperm. However, more research must be performed particularly to find the best sorting buffer to effectively sex-sort sperm while providing high motility and sperm viability.
Collapse
Affiliation(s)
- Tuempong Wongtawan
- Akkhraratchakumari Veterinary College, Walailak University, Thai Buri Tha Sala, Nakhon Si Thammarat, 80160, Thailand
- Centre for One Health, Walailak University, Thai Buri Tha Sala, Nakhon Si Thammarat, 80160, Thailand
- Laboratory of Veterinary Biomedicine, Mahidol University, Salaya, Puttamonthon, Nakhon Pathom, 73170, Thailand
- Corresponding author.
| | - Naruphorn Dararatana
- Laboratory of Veterinary Biomedicine, Mahidol University, Salaya, Puttamonthon, Nakhon Pathom, 73170, Thailand
- Department of Biomedical Engineering, Faculty of Engineer, Mahidol University, Salaya, Puttamonthon, Nakhon Pathom, 73170, Thailand
| | - Chommanart Thongkittidilok
- Akkhraratchakumari Veterinary College, Walailak University, Thai Buri Tha Sala, Nakhon Si Thammarat, 80160, Thailand
- Centre for One Health, Walailak University, Thai Buri Tha Sala, Nakhon Si Thammarat, 80160, Thailand
| | - Sudsaijai Kornmatitsuk
- Laboratory of Veterinary Biomedicine, Mahidol University, Salaya, Puttamonthon, Nakhon Pathom, 73170, Thailand
- Department of Clinical Science and Public Health, Faculty of Veterinary Science, Mahidol University, Salaya, Puttamonthon, Nakhon Pathom, 73170, Thailand
| | - Bovornlak Oonkhanond
- Department of Biomedical Engineering, Faculty of Engineer, Mahidol University, Salaya, Puttamonthon, Nakhon Pathom, 73170, Thailand
| |
Collapse
|
3
|
Abstract
Total Joint Replacement (TJR) devices undergo standardized wear testing in mechanical simulators while submerged in a proteinaceous testing solution to mimic the environmental conditions of artificial joints in the human body. Typically, bovine calf serum is used to provide the required protein content. However, due to lot-to-lot variability, an undesirable variance in testing outcome is observed. Based on an earlier finding that yellowish-orange serum color saturation is associated with wear rate, we examined potential sources of this variability, by running a comparative wear test with bilirubin; hemin; and a fatty acid, oleic acid, in the lubricant. All these compounds readily bind to albumin, the most abundant protein in bovine serum. Ultrahigh molecular weight polyethylene (UHMWPE) pins were articulated against CoCrMo discs in a pin-on-disc tribometer, and the UHMWPE wear rates were compared between lubricants. We found that the addition of bilirubin increased wear by 121%, while hemin had a much weaker, insignificant effect. When added at the same molar ratio as bilirubin, the fatty acid tended to reduce wear. Additionally, there was a significant interaction with respect to bilirubin and hemin in that UHMWPE wear rate decreased with increasing fatty acid concentration. We believe the conformational change in albumin by binding bilirubin makes it more likely to form molecular bridges between UHMWPE and the metal counterface, thus increasing adhesive wear. However, fatty acids compete for binding sites on albumin, and can prevent this conformational change. Hence, the protein is stabilized, and the chance for albumin to form bridges is lowered. Ultimately, UHMWPE wear rate is driven by the competitive binding of bilirubin and fatty acid to albumin.
Collapse
|