1
|
To KV, Dahlgren C, Zhang X, Wang S, Wipf DO, Schilling MW, Dinh T. Inosine 5'- monophosphate derived umami taste intensity of beef determination by electrochemistry and chromatography. Meat Sci 2023; 206:109343. [PMID: 37717339 DOI: 10.1016/j.meatsci.2023.109343] [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: 07/07/2023] [Revised: 09/10/2023] [Accepted: 09/12/2023] [Indexed: 09/19/2023]
Abstract
The umami sensation contributes to beef taste and acceptability. Inosine 5'- monophosphate (IMP), the most abundant 5'-ribonucleotide in meat, is known to impart an umami taste without the undesired side effects commonly associated with glutamate. Nevertheless, the investigation of IMP's role in beef flavor has thus far been overlooked. Traditional methods for detecting IMP have relied on liquid chromatography coupled with ultraviolet spectroscopy or mass spectrometry techniques. However, these methods are not practical for production settings due to the complexity and resource demands of sophisticated laboratory techniques. Alternative methods like cyclic voltammetry might offer more practical solutions for rapidly detecting IMP. The objectives of this study were to evaluate the efficiency of using electrochemistry and chromatography on differentiating beef strips spiked with different IMP contents. The IMP threshold was 0.30 mM determined by a trained panel using the Best Estimates Threshold method. Beef strip steaks of USDA Prime, Choice, and Select were spiked at 0.30 and 0.60 mM of IMP, based on green weight and an estimated moisture content of 65%. In this study, differences in the IMP content of steaks were not detected by liquid chromatography-mass spectrometry. However, the cyclic voltammetry approach differentiated IMP concentrations at 0.50 mM or above in aqueous solutions and subsequentially meat extracts from the buffered blank solutions. In conclusion, cyclic voltammetry holds potential as a rapid and effective approach for detecting IMP in beef and other meat products, offering promising applications for future research.
Collapse
Affiliation(s)
- K Virellia To
- Department of Food Science and Technology, Virginia Polytechnic Institute and State University, Blacksburg, VA 24060, USA
| | - Chelsie Dahlgren
- Department of Animal and Dairy Science, Mississippi State University, Mississippi State, MS 39762, USA
| | - Xue Zhang
- Department of Food Science, Nutrition, and Health Promotion, Mississippi State University, Mississippi State, MS 39762, USA
| | - Shangshang Wang
- Department of Animal and Dairy Science, Mississippi State University, Mississippi State, MS 39762, USA
| | - David O Wipf
- Department of Chemistry, Mississippi State University, Mississippi State, MS 39762, USA
| | - M Wes Schilling
- Department of Food Science, Nutrition, and Health Promotion, Mississippi State University, Mississippi State, MS 39762, USA
| | - Thu Dinh
- Tyson Foods Inc., Springdale, AR 72762, USA.
| |
Collapse
|
2
|
Theerthagiri J, Lee SJ, Karuppasamy K, Park J, Yu Y, Kumari MLA, Chandrasekaran S, Kim HS, Choi MY. Fabrication strategies and surface tuning of hierarchical gold nanostructures for electrochemical detection and removal of toxic pollutants. JOURNAL OF HAZARDOUS MATERIALS 2021; 420:126648. [PMID: 34329090 DOI: 10.1016/j.jhazmat.2021.126648] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 07/10/2021] [Accepted: 07/12/2021] [Indexed: 05/20/2023]
Abstract
The intensive research on the synthesis and characterization of gold (Au) nanostructures has been extensively documented over the last decades. These investigations allow the researchers to understand the relationships between the intrinsic properties of Au nanostructures such as particle size, shape, morphology, and composition to synthesize the Au nano/hybrid nanostructures with novel physicochemical properties. By tuning the properties above, these nanostructures are extensively employed to detect and remove trace amounts of toxic pollutants from the environment. This review attempts to document the achievements and current progress in Au-based nanostructures, general synthetic and fabrication strategies and their utilization in electrochemical sensing and environmental remediation applications. Additionally, the applications of Au nanostructures (e.g., as adsorbents, sensing platforms, catalysts, and electrodes) and advancements in the field of electrochemical sensing of different target analytes (e.g., proteins, nucleic acids, heavy metals, small molecules, and antigens) are summarized. The literature survey concludes the existing methods for the detection of toxic contaminants at various concentration levels. Finally, the existing challenges and future research directions on electrochemical sensing and degradation of toxic contaminants using Au nanostructures are defined.
Collapse
Affiliation(s)
- Jayaraman Theerthagiri
- Core-Facility Center for Photochemistry & Nanomaterials, Department of Chemistry (BK21 FOUR), Research Institute of Natural Sciences, Gyeongsang National University, Jinju 52828, South Korea
| | - Seung Jun Lee
- Core-Facility Center for Photochemistry & Nanomaterials, Department of Chemistry (BK21 FOUR), Research Institute of Natural Sciences, Gyeongsang National University, Jinju 52828, South Korea
| | - K Karuppasamy
- Division of Electronics and Electrical Engineering, Dongguk University-Seoul, Seoul 04620, Republic of Korea
| | - Juhyeon Park
- Core-Facility Center for Photochemistry & Nanomaterials, Department of Chemistry (BK21 FOUR), Research Institute of Natural Sciences, Gyeongsang National University, Jinju 52828, South Korea
| | - Yiseul Yu
- Core-Facility Center for Photochemistry & Nanomaterials, Department of Chemistry (BK21 FOUR), Research Institute of Natural Sciences, Gyeongsang National University, Jinju 52828, South Korea
| | - M L Aruna Kumari
- Department of Chemistry, M.S. Ramaiah College of Arts, Science and Commerce, Bengaluru 560054, India
| | - Sivaraman Chandrasekaran
- Center of Excellence in Environmental Studies, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Hyun-Seok Kim
- Division of Electronics and Electrical Engineering, Dongguk University-Seoul, Seoul 04620, Republic of Korea
| | - Myong Yong Choi
- Core-Facility Center for Photochemistry & Nanomaterials, Department of Chemistry (BK21 FOUR), Research Institute of Natural Sciences, Gyeongsang National University, Jinju 52828, South Korea.
| |
Collapse
|
3
|
Yang X, Qiu P, Yang J, Fan Y, Wang L, Jiang W, Cheng X, Deng Y, Luo W. Mesoporous Materials-Based Electrochemical Biosensors from Enzymatic to Nonenzymatic. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2021; 17:e1904022. [PMID: 31643131 DOI: 10.1002/smll.201904022] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 09/07/2019] [Indexed: 05/04/2023]
Abstract
Mesoporous materials have drawn more and more attention in the field of biosensors due to their high surface areas, large pore volumes, tunable pore sizes, as well as abundant frameworks. In this review, the progress on mesoporous materials-based biosensors from enzymatic to nonenzymatic are highlighted. First, recent advances on the application of mesoporous materials as supports to stabilize enzymes in enzymatic biosensing technology are summarized. Special emphasis is placed on the effect of pore size, pore structure, and surface functional groups of the support on the immobilization efficiency of enzymes and the biosensing performance. Then, the development of a nonenzymatic strategy that uses the intrinsic property of mesoporous materials (carbon, silica, metals, and composites) to mimic the behavior of enzymes for electrochemical sensing of some biomolecules is discussed. Finally, the challenges and perspective on the future development of biosensors based on mesoporous materials are proposed.
Collapse
Affiliation(s)
- Xuanyu Yang
- Department of Chemistry, State Key Laboratory of Molecular Engineering of Polymers, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, iChEM, Fudan University, Shanghai, 200433, China
| | - Pengpeng Qiu
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Institute of Functional Materials, Donghua University, Shanghai, 201620, China
| | - Jianping Yang
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Institute of Functional Materials, Donghua University, Shanghai, 201620, China
| | - Yuchi Fan
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Institute of Functional Materials, Donghua University, Shanghai, 201620, China
| | - Lianjun Wang
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Institute of Functional Materials, Donghua University, Shanghai, 201620, China
| | - Wan Jiang
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Institute of Functional Materials, Donghua University, Shanghai, 201620, China
| | - Xiaowei Cheng
- Department of Chemistry, State Key Laboratory of Molecular Engineering of Polymers, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, iChEM, Fudan University, Shanghai, 200433, China
| | - Yonghui Deng
- Department of Chemistry, State Key Laboratory of Molecular Engineering of Polymers, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, iChEM, Fudan University, Shanghai, 200433, China
| | - Wei Luo
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Institute of Functional Materials, Donghua University, Shanghai, 201620, China
| |
Collapse
|
4
|
Kalambate PK, Rao Z, Dhanjai, Wu J, Shen Y, Boddula R, Huang Y. Electrochemical (bio) sensors go green. Biosens Bioelectron 2020; 163:112270. [PMID: 32568692 DOI: 10.1016/j.bios.2020.112270] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 04/12/2020] [Accepted: 05/01/2020] [Indexed: 10/24/2022]
Abstract
Electrochemical (bio) sensors are now widely acknowledged as a sensitive detection tool for disease diagnosis as well as the detection of numerous species of pharmaceutical, clinical, industrial, food, and environmental origin. The term 'green' demonstrates the development of electrochemical (bio) sensing platforms utilizing biodegradable and sustainable materials. Development of green sensing platforms is one of the most active areas of research minimizing the use of toxic/hazardous reagents and solvent systems, thereby further reducing the production of chemical wastes in sensor fabrication. The present review includes green electrochemical (bio) sensors which are based on firstly, green sensors comprising natural and non-hazardous materials (e.g., paper/clay/zeolites/biowastes), secondly sensors based on nanomaterials synthesized by green methods and lastly sensors constituting green solvents (e.g., ionic liquids/deep eutectic solvents). Electrochemical performances of such green sensors and their benefits such as biodegradability, non-toxicity, sustainability, low-cost, sensitive surfaces, etc. Have been discussed for quantification of various target analytes. Associated challenges, possible solutions, and opportunities towards fabricating green electrochemical sensors and biosensors have been provided in the conclusion section.
Collapse
Affiliation(s)
- Pramod K Kalambate
- State Key Laboratory of Materials Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, Hubei, 430074, PR China
| | - Zhixiang Rao
- State Key Laboratory of Materials Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, Hubei, 430074, PR China
| | - Dhanjai
- Department of Mathematical and Physical Sciences, Concordia University of Edmonton, Alberta, T5B 4E4, Canada
| | - Jingyi Wu
- State Key Laboratory of Materials Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, Hubei, 430074, PR China
| | - Yue Shen
- State Key Laboratory of Materials Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, Hubei, 430074, PR China
| | - Rajender Boddula
- Chinese Academy of Sciences (CAS), Center for Excellence in Nanoscience, CAS Key Laboratory of Nanosystem and Hierarchy Fabrication, National Centre for Nanoscience and Technology, Beijing, 100190, PR China
| | - Yunhui Huang
- State Key Laboratory of Materials Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, Hubei, 430074, PR China.
| |
Collapse
|
5
|
Tang P, Tang X, Mei S, Xie Y, Liu L, Ren L. Electrochemical antioxidant screening and evaluation based on guanine and chitosan immobilized MoS2 nanosheet modified glassy carbon electrode (guanine/CS/MoS2/GCE). OPEN CHEM 2020. [DOI: 10.1515/chem-2020-0003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
AbstractIn this study, an electrochemical biosensor based on guanine and chitosan immobilized MoS2 nanosheet modified glassy carbon electrode (guanine/CS/MoS2/GCE) was developed and employed for antioxidant screening and antioxidant capacity evaluation. The oxidation peak current of guanine was improved and nearly tripled after modifications of chitosan and MoS2 nanosheet. The immobilized guanine could be damaged by hydroxyl radicals generated in Fenton solution. However, in the presence of antioxidants, the guanine was protected and the oxidation peak current of guanine increased. This process mimics the mechanism of antioxidant protection in human body. The factors affecting preparation of sensor and detection of antioxidant capacity were optimized. At the optimum conditions, the guanine/CS/MoS2/GCE showed wide linear range, low detection limit, satisfactory reproducibility and stability for detection. Ascorbic acid was used as a model antioxidant to evaluate the antioxidant capacity. A good linearity was observed with a correlation coefficient of 0.9959 in the concentrations between 0.5 and 4.0 mg L-1. The antioxidant capacities of three flavonoids were also tested and the rank of antioxidant capacities was ascorbic acid (51.84%), quercetin (45.82%), fisetin (34.39%) and catechin (16.99%). Due to the rapid measurement and low cost, this sensor could provide an available sensing platform for antioxidant screening and evaluation.
Collapse
Affiliation(s)
- Ping Tang
- School of Environmental Science and Engineering, Hubei Polytechnic University, Hubei Key Laboratory of Mine Environmental Pollution Control and Remediation, Huangshi, 435003, China
| | - Xiaosheng Tang
- Hubei Key Laboratory of Edible Wild Plants Conservation and Utilization & National Demonstration Center for Experimental Biology Education & College of Life Sciences, Hubei Normal University, Huangshi, 435002, China
| | - Shiyong Mei
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha410205, China
| | - Yixi Xie
- Key Laboratory for Green Organic Synthesis and Application of Hunan Province, College of Chemistry, Xiangtan University, Xiangtan, 411105, China
| | - Liangliang Liu
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha410205, China
| | - Licheng Ren
- Department of Burn and Reconstructive Surgery, Xiangya Hospital, Central South University, Changsha410083, China
| |
Collapse
|
6
|
Au and Au-Based nanomaterials: Synthesis and recent progress in electrochemical sensor applications. Talanta 2020; 206:120210. [DOI: 10.1016/j.talanta.2019.120210] [Citation(s) in RCA: 124] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 07/25/2019] [Accepted: 07/31/2019] [Indexed: 12/28/2022]
|
7
|
Kamaci UD, Kamaci M, Peksel A. Poly(azomethine-urethane) and zeolite-based composite: Fluorescent biosensor for DNA detection. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2019; 212:232-239. [PMID: 30641363 DOI: 10.1016/j.saa.2019.01.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 12/14/2018] [Accepted: 01/05/2019] [Indexed: 05/28/2023]
Abstract
In the present paper, a highly selective and sensitive fluorescent biosensor based on poly(azomethine-urethane) and zeolite for the determination of DNA molecules was developed. Zeolite was chosen to enhance with anionic or cationic functional groups in polymer matrix and interaction between polymer and DNA. Several parameters such as polymer concentration, pH and incubation time effect on the sensitivity of the fluorescent biosensor were optimized. Linear range was determined between 2.50 and 25.00 nmol/L DNA concentration and limit of detection (LOD) of the biosensor was calculated as 0.095 nmol/L under the optimal conditions. Interference study was also performed in the presence of different amino acids, cations and organic compounds. The results clearly indicated that the tested cations and compounds were not induced a significant fluorescence change and the proposed zeolite-based biosensor was shown a good selectivity for DNA.
Collapse
Affiliation(s)
- Umran Duru Kamaci
- Faculty of Arts and Sciences, Department of Chemistry, Yıldız Technical University, Esenler, 34220 Istanbul, Turkey
| | - Musa Kamaci
- Piri Reis University, Tuzla, 34940 Istanbul, Turkey.
| | - Aysegul Peksel
- Faculty of Arts and Sciences, Department of Chemistry, Yıldız Technical University, Esenler, 34220 Istanbul, Turkey
| |
Collapse
|
8
|
Anu Prathap MU, Kaur B, Srivastava R. Electrochemical Sensor Platforms Based on Nanostructured Metal Oxides, and Zeolite-Based Materials. CHEM REC 2018; 19:883-907. [DOI: 10.1002/tcr.201800068] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 10/19/2018] [Indexed: 11/11/2022]
Affiliation(s)
- M. U. Anu Prathap
- Department of Biological Systems Engineering; University of Wisconsin−Madison; 460 Henry Mall Madison, WI 53706 USA
- Department of Chemistry; Indian Institute of Technology Ropar; Rupnagar Punjab 140001 India
| | - Balwinder Kaur
- Department of Chemistry; University of Massachusetts Lowell; 256 Riverside Street,Olney Hall Lowell, MA 01845 USA
- Department of Chemistry; Indian Institute of Technology Ropar; Rupnagar Punjab 140001 India
| | - Rajendra Srivastava
- Department of Chemistry; Indian Institute of Technology Ropar; Rupnagar Punjab 140001 India
| |
Collapse
|
9
|
He S, He P, Zhang X, Zhang X, Liu K, Jia L, Dong F. Poly(glycine)/graphene oxide modified glassy carbon electrode: Preparation, characterization and simultaneous electrochemical determination of dopamine, uric acid, guanine and adenine. Anal Chim Acta 2018; 1031:75-82. [PMID: 30119746 DOI: 10.1016/j.aca.2018.06.020] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 06/03/2018] [Accepted: 06/07/2018] [Indexed: 12/01/2022]
Abstract
A novel poly(glycine) (p-GLY)/graphene oxide (GO) composite based sensor (p-GLY/GO) was successfully prepared on glassy carbon electrode by simple electropolymerization. Electrochemical responses of analytes on p-GLY/GO modified electrode were studied by cyclic voltammetry and differential pulse voltammetry. The results demonstrated that p-GLY/GO modified electrode showed a favorable application for the simultaneous determination of dopamine (DA), uric acid (UA), guanine (GU) and adenine (AD). Owing to the synergistic effect of p-GLY and GO, the oxidation peaks of four analytes separated well from each other, and the potential separations of oxidation peaks of DA-UA, UA-GU and GU-AD were large up to 170, 350 and 300 mV, respectively. As-prepared p-GLY/GO modified electrode offered wide linear responses for DA, UA, GU and AD over the ranges of 0.20-62, 0.10-105, 0.15-48 and 0.090-103 μM with detection limits of 0.011, 0.061, 0.026 and 0.030 μM (S/N = 3), respectively. Moreover, p-GLY/GO modified electrode presented favorable selectivity, stability and reproducibility, which was a promising candidate as an electrochemical sensor for the simultaneous determination of DA, UA, GU and AD.
Collapse
Affiliation(s)
- Shaoying He
- School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang, 621010, Sichuan, PR China; State Key Laboratory for Environment-friendly Energy Materials, Southwest University of Science and Technology, Mianyang, 621010, Sichuan, PR China
| | - Ping He
- School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang, 621010, Sichuan, PR China; Mianyang Kingtiger New Energy Technology Co. Ltd., Mianyang, 621000, Sichuan, PR China.
| | - Xingquan Zhang
- Center of Analysis and Test, Southwest University of Science and Technology, Mianyang, 621010, Sichuan, PR China
| | - Xiaojuan Zhang
- School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang, 621010, Sichuan, PR China
| | - Kaili Liu
- School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang, 621010, Sichuan, PR China
| | - Lingpu Jia
- School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang, 621010, Sichuan, PR China
| | - Faqin Dong
- Key Laboratory of Solid Waste Treatment and Resource Recycle of Ministry of Education, Southwest University of Science and Technology, Mianyang, 621010, Sichuan, PR China
| |
Collapse
|
10
|
He S, He P, Zhang X, Zhang X, Li C, Dong F, Lei H, Liu D. Poly(bromocresol green)/carbon quantum dots modified electrode for the simultaneous electrochemical determination of guanine and adenine. J Electroanal Chem (Lausanne) 2017. [DOI: 10.1016/j.jelechem.2017.10.069] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
11
|
Manivannan S, Jeong J, Kang DK, Kim K. One-step Synthesis of AuAg Alloy Nanodots and its Electrochemical Studies towards Nitrobenzene Reduction and Sensing. ELECTROANAL 2017. [DOI: 10.1002/elan.201700451] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Shanmugam Manivannan
- Electrochemistry Laboratory for Sensors & Energy (ELSE), Department of Chemistry; Incheon National University; Incheon 22012 Republic of Korea
| | - Juwon Jeong
- Electrochemistry Laboratory for Sensors & Energy (ELSE), Department of Chemistry; Incheon National University; Incheon 22012 Republic of Korea
| | - Dong-Ku Kang
- Electrochemistry Laboratory for Sensors & Energy (ELSE), Department of Chemistry; Incheon National University; Incheon 22012 Republic of Korea
| | - Kyuwon Kim
- Electrochemistry Laboratory for Sensors & Energy (ELSE), Department of Chemistry; Incheon National University; Incheon 22012 Republic of Korea
| |
Collapse
|