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A highly sensitive strategy for glypican-3 detection based on aptamer/gold carbon dots/magnetic graphene oxide nanosheets as fluorescent biosensor. Anal Bioanal Chem 2022; 414:6441-6453. [PMID: 35788872 DOI: 10.1007/s00216-022-04201-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Revised: 05/30/2022] [Accepted: 06/24/2022] [Indexed: 11/01/2022]
Abstract
Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related deaths in China. Glypican-3 (GPC3) is a specific antigen related to HCC, which is widely used in clinical detection as a reliable marker of HCC. In this paper, a highly sensitive homogeneous apatasensor was designed for GPC3 detection based on fluorescence resonance energy transfer (FRET) where the GPC3 aptamer labelled gold carbon dots (AuCDs-GPC3Apt) are used as a donor and magnetic graphene oxide (Fe3O4/GO) nanosheets are used as an acceptor. A one-step hydrothermal method was used to synthesize AuCDs to provide sufficient fluorescence. The FRET phenomenon exists between AuCDs-GPC3Apt and Fe3O4/GO, which weakens the fluorescence intensity of the whole system. When the target GPC3 is added to the FRET system, the fluorescent AuCDs-GPC3Apt binds to the GPC3 and forms a folded structure, which leads to AuCDs-GPC3Apt separation from Fe3O4/GO nanosheets. The Fe3O4/GO is then magnetically separated so that the fluorescence of free labelled AuCDs-GPC3Apt is restored. Under the optimum conditions, the fluorescence recovery rate is linearly correlated with the concentration of GPC3 (5-100 ng·mL-1) and the detection limit is 3.01 ng·mL-1 (S/N = 3). This strategy shows recoveries from 98.76 to 101.29% in real human serum samples and provides an immediate and effective detection method for the quantification of GPC3 with great potential applications for early diagnosis of HCC. A sensitive homogeneous FRET-based apatasensor was designed for GPC3 detection where the AuCDs-GPC3Apt is a donor and Fe3O4/GO nanosheets are an acceptor. The GPC3 fluorescent aptasensor combines wider output range with low cost, high specificity, and good anti-interference.
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Gao Y, Yu H, Tian J, Xiao B. Nonenzymatic DNA-Based Fluorescence Biosensor Combining Carbon Dots and Graphene Oxide with Target-Induced DNA Strand Displacement for microRNA Detection. NANOMATERIALS (BASEL, SWITZERLAND) 2021; 11:2608. [PMID: 34685049 PMCID: PMC8537593 DOI: 10.3390/nano11102608] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 09/24/2021] [Accepted: 09/30/2021] [Indexed: 12/18/2022]
Abstract
Based on a fluorescence "on-off-on" strategy, we fabricated a simple and highly sensitive DNA-based fluorescence biosensor for the detection of micro (mi)RNA from carbon dots (CDs) and graphene oxide (GO) without complicated and time-consuming operations. CDs were successfully synthesized and conjugated to the end of a single-stranded fuel DNA that was adsorbed onto the surface of GO through π-π stacking, resulting in fluorescence quenching. In the presence of the target miRNA let-7a, the fuel DNA was desorbed from the GO surface, and fluorescence was restored through two successive toehold-mediated strand displacement reactions on double-stranded DNA-modified gold nanoparticles. The target miRNA let-7a was recycled, leading to signal amplification. The concentration of let-7a was proportional to the degree of fluorescence recovery. Under optimal conditions, there was a good linear relationship between the relative fluorescence intensity and let-7a concentration in the range of 0.01-1 nM, with a detection limit of 7.8 pM. With its advantages of signal amplification and high biocompatibility, this fluorescence sensing strategy can be applied to the detection of a variety of target miRNAs and can guide the design of novel biosensors with improved properties.
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Affiliation(s)
- Yuanyuan Gao
- Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, China; (Y.G.); (H.Y.)
- State Key Laboratory of Marine Resource Utilization in South China Sea, School of Material Science and Engineering, Hainan University, Haikou 570228, China;
| | - Hong Yu
- Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, China; (Y.G.); (H.Y.)
| | - Jingjing Tian
- State Key Laboratory of Marine Resource Utilization in South China Sea, School of Material Science and Engineering, Hainan University, Haikou 570228, China;
- Key Laboratory of Emergency and Trauma of Ministry of Education & Research Unit of Island Emergency Medicine of Chinese Academy of Medical Sciences, Hainan Medical University, Haikou 571199, China
| | - Botao Xiao
- Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, China; (Y.G.); (H.Y.)
- Joint International Research Laboratory of Synthetic Biology and Medicine, School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, China
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Sulfur-doped carbon dots@polydopamine-functionalized magnetic silver nanocubes for dual-modality detection of norovirus. Biosens Bioelectron 2021; 193:113540. [PMID: 34403935 DOI: 10.1016/j.bios.2021.113540] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Revised: 07/23/2021] [Accepted: 08/01/2021] [Indexed: 12/27/2022]
Abstract
Synergistic dual-mode optical platforms are up-and-coming detection tools in the diagnosis and management of infectious diseases. Here, novel dual-modality fluorescence (FL) and surface-enhanced Raman scattering (SERS) techniques have been integrated into a single probe for the rapid and ultrasensitive detection of norovirus (NoV). The developed FL-SER-based biosensor relies on the dual-signal enhancements of newly synthesized sulfur-doped agar-derived carbon dots (S-agCDs). The antigen-antibody immunoreaction results in forming a core-satellite immunocomplex between anti-NoV antibody-conjugated S-agCDs and polydopamine-functionalized magnetic silver nanocubes [poly (dop)-MNPs-Ag NCs]. By deploying an immunomagnetic enrichment protocol and performing the SERS modality on a single-layer graphene substrate, norovirus-like particles (NoV-LPs) were detected across a wide range of 1 fg mL-1 - 10 ng mL-1 with an excellent limit of detection of 0.1 fg mL-1. The combined advantage of the dual-signaling properties of the biosensor was demonstrated using FL confocal imaging for "hotspots" tracking prior to SERS detection of clinical NoV in fecal specimen down to ⁓10 RNA copies mL-1. The proposed dual-modality biosensor's performance increases the prospect of a rapid and low-cost sensitive NoV detection and surveillance option for public health.
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Yan Y, Ma C, Tang Z, Chen M, Zhao H. A novel fluorescent assay based on DNAzyme-assisted detection of prostate specific antigen for signal amplification. Anal Chim Acta 2020; 1104:172-179. [PMID: 32106949 DOI: 10.1016/j.aca.2020.01.014] [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: 04/10/2019] [Revised: 11/23/2019] [Accepted: 01/07/2020] [Indexed: 12/13/2022]
Abstract
Prostate specific antigen (PSA) is one of the most common biomarkers for the management of prostate cancer. However, it still remains urgent to develop highly sensitive, cost-effective and selective strategies for PSA assay. In this paper, we developed a low-cost, highly sensitive and specific analytical strategy for the detection of PSA by using a fluorescence sensor based on Pb2+-dependent DNAzyme. We designed a DNA sequence called cmMB with a hairpin structure, containing PSA-specific aptamers and Pb2+-dependent DNAzyme chains. Also, a fluorophore-labelled DNA sequence called Sub-FAM, which contains a cleavage site of Pb2+-dependent DNAzyme and serves as substrate, is also designed for the signal generation. In the presence of PSA, interaction between aptamer and PSA blocks the hairpin structure of cmMB, resulting in the formation of Pb2+-dependent DNAzyme with Pb2+. Then, Pb2+-dependent DNAzyme can cleavage Sub-FAM and produce a high fluorescence. In the absence of PSA, since Sub-FAM remains to be ssDNA and can be absorbed by GO, only low fluorescence can be detected. Under optimal experimental conditions, a good linear relationship in the range of 1-100 pg mL-1 was exhibited, with a limit of detection (LOD) of 0.76 pg mL-1. In addition, the proposed method has potential value in the diagnosis and monitoring of prostate cancer because of its good selectivity and practical application in biological samples.
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Affiliation(s)
- Ying Yan
- School of Life Sciences, Central South University, Changsha, 410013, China
| | - Changbei Ma
- School of Life Sciences, Central South University, Changsha, 410013, China.
| | - Zhenwei Tang
- School of Life Sciences, Central South University, Changsha, 410013, China
| | - Mingjian Chen
- School of Life Sciences, Central South University, Changsha, 410013, China
| | - Han Zhao
- School of Life Sciences, Central South University, Changsha, 410013, China
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Gao Y, Tian J, Zhang X, Qiao B, Cao Y, Wang X, Wu Q. A fluorescence assay for microRNA let-7a by a double-stranded DNA modified gold nanoparticle nanoprobe combined with graphene oxide. Analyst 2020; 145:1190-1194. [DOI: 10.1039/c9an02274k] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
A fluorescence switching platform was developed to monitor target microRNA let-7a by coupling dsDNA–AuNPs with the GO nanosheet.
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Affiliation(s)
- Yuanyuan Gao
- State Key Laboratory of Marine Resource Utilization in South China Sea
- College of Material science and Engineering
- Hainan University
- Haikou 570228
- China
| | - Jingjing Tian
- State Key Laboratory of Marine Resource Utilization in South China Sea
- College of Material science and Engineering
- Hainan University
- Haikou 570228
- China
| | - Xing Zhang
- State Key Laboratory of Marine Resource Utilization in South China Sea
- College of Material science and Engineering
- Hainan University
- Haikou 570228
- China
| | - Bin Qiao
- Key Laboratory of Emergency and Trauma of Ministry of Education & Research Unit of Island Emergency Medicine of Chinese Academy of Medical Sciences
- Hainan Medical University
- Haikou 571199
- China
- School of Tropical Medicine and Laboratory Medicine
| | - Yang Cao
- Qiongtai Normal University
- Haikou 571127
- China
| | - Xiaohong Wang
- State Key Laboratory of Marine Resource Utilization in South China Sea
- College of Material science and Engineering
- Hainan University
- Haikou 570228
- China
| | - Qiang Wu
- Key Laboratory of Emergency and Trauma of Ministry of Education & Research Unit of Island Emergency Medicine of Chinese Academy of Medical Sciences
- Hainan Medical University
- Haikou 571199
- China
- School of Tropical Medicine and Laboratory Medicine
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Qin P, Huang D, Xu Z, Guan Y, Bing Y, Yu A. A potential reusable fluorescent aptasensor based on magnetic nanoparticles for ochratoxin A analysis. OPEN CHEM 2019. [DOI: 10.1515/chem-2019-0140] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
AbstractAn aptasensor for the detection of ochratoxin A (OTA) in environmental samples was developed. It displayed high sensitivity and good selectivity. Factors such as specific binding between a FAM (5-carboxyfluorescein)-labeled aptamer (f-RP) and OTA, and a magnetic property of a streptavidin magbeads-modified capture probe (bm-CP) resulted in aptasensor’s linear relationship between fluorescence intensity and the concentration of OTA. This characteristic is present at the OTA concentration ranges from 0.100 μM to 25.00 μM with a LOD (limit of detection) of 0.0690 μM. The bm-CP can be reused through melting, washing and magnetic separation, which contributes to cost reduction. In addition, the proposed method is simple and detection process is fast. The aptasensor can be used in real samples.
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Affiliation(s)
- Pinzhu Qin
- School of Environment and Ecology, Jiangsu Open University, 832 Yingtian Street, Nanjing, Jiangsu, 210019, P.R. China
- Jiangsu Province Key Laboratory of Environmental Engineering, Nanjing, Jiangsu, 210036, P.R. China
| | - Dawei Huang
- South China Institute of Environmental Sciences, Ministry of Ecology and Environment of PRC, Guangzhou, 510655, P.R. China
| | - Zihao Xu
- School of Environment and Ecology, Jiangsu Open University, 832 Yingtian Street, Nanjing, Jiangsu, 210019, P.R. China
| | - Ying Guan
- School of Environment and Ecology, Jiangsu Open University, 832 Yingtian Street, Nanjing, Jiangsu, 210019, P.R. China
- Jiangsu Province Key Laboratory of Environmental Engineering, Nanjing, Jiangsu, 210036, P.R. China
| | - Yongxin Bing
- South China Institute of Environmental Sciences, Ministry of Ecology and Environment of PRC, Guangzhou, 510655, P.R. China
| | - Ang Yu
- Jiangsu Province Key Laboratory of Environmental Engineering, Nanjing, Jiangsu, 210036, P.R. China
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Chen M, Ma C, Zhao H, Yan Y. Exonuclease III-assisted fluorometric aptasensor for the carcinoembryonic antigen using graphene oxide and 2-aminopurine. Mikrochim Acta 2019; 186:500. [PMID: 31270630 DOI: 10.1007/s00604-019-3621-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Accepted: 06/15/2019] [Indexed: 01/04/2023]
Abstract
A reliable fluorometric assay is described for the determination carcinoembryonic antigen (CEA) using exonuclease III (Exo III) and a 2-aminopurine binding aptamer. In the absence of CEA, dsDNA is degraded by Exo III, and free 2-AP (which has a blue fluorescence with excitation/emission maxima of 310/365 nm) is released. Strong fluorescence is generated after addition of graphene oxide (GO) to the solution. However, the 2-AP modified DNA (T2) cannot be degraded in the presence of CEA by Exo III due to the interaction between CEA and aptamer T1. Hence, only weak fluorescence can be detected after addition of GO. In this system, CEA can be quantified in the 0.05 - 2 ng·mL-1 concentration range with a detection limit of 30 pg·mL-1 (at S/N = 3). The method was successfully applied to analyze serum samples for CEA. Graphical Abstract An exonuclease III-assisted fluorometric aptasensor has been developed for the detection of carcinoembryonic antigen using graphene oxide and 2-aminopurine.
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Affiliation(s)
- Mingjian Chen
- School of Life Sciences, Central South University, Changsha, 410013, China
| | - Changbei Ma
- School of Life Sciences, Central South University, Changsha, 410013, China.
| | - Han Zhao
- School of Life Sciences, Central South University, Changsha, 410013, China
| | - Ying Yan
- School of Life Sciences, Central South University, Changsha, 410013, China
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Fluorometric determination of mercury(II) via a graphene oxide-based assay using exonuclease III-assisted signal amplification and thymidine-Hg(II)-thymidine interaction. Mikrochim Acta 2019; 186:216. [PMID: 30838468 DOI: 10.1007/s00604-019-3332-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2018] [Accepted: 02/22/2019] [Indexed: 12/26/2022]
Abstract
A highly sensitive and selective fluorometric method is described for determination of mercury(II). It is based on (a) the use of graphene oxide (GO) acting as a quencher of the fluoresence of the carboxy-fluorescein (FAM), and (b) of Hg(II)-triggered cleavage of the newly formed nucleic acid sequences harbored blunt 3'-hydroxyl termini by exonuclease III (Exo III) that leads to signal amplification. Two DNA probes are used, viz. a capture probe (CP) and a help probe; HP) that is partially complementary. In the absence of Hg(II), the FAM-labeled hairpin (signal probe, SP) is adsorbed onto the surface of GO via π-stacking interactions. CP blocks the release of the HP for binding to SP. This results in quenching of the green fluorescence of the label. Upon addition of Hg(II), the linear structure of CP is converted to a hairpin structure due to the formation of thymidine-Hg(II)-thymidine duplexes. HP is released from the CP/HP hybrids, and this causes SP to be released from from GO and fluorescence to be recovered. The signal is strongly amplified by using Exo III-assisted targeting and recycling of HP. Hence, Hg(II) can be detected via the strong increase in fluorescence. The method has a linear response in the 0.1 to 30 nM Hg(II) concentration range and a 10 pM detection limit. It was applied to the determination of Hg(II) in three (spiked) Chinese medicines. Graphical abstract Schematic representation of fluorescence sensing strategy for Hg2+ by using graphene oxide as a quencher and exonuclease III-assisted signal amplification.
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Chen M, Li W, Ma C, Wu K, He H, Wang K. Fluorometric determination of the activity of uracil-DNA glycosylase by using graphene oxide and exonuclease I assisted signal amplification. Mikrochim Acta 2019; 186:110. [PMID: 30637581 DOI: 10.1007/s00604-019-3247-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 01/05/2019] [Indexed: 10/27/2022]
Abstract
The base-excision repair enzyme uracil-DNA glycosylase (UDG) plays a crucial role in the maintenance of genome integrity. The authors describe a fluorometric method for the detection of the activity of UDG. It is making use of (a) a 3'-FAM-labeled hairpin DNA probe with two uracil deoxyribonucleotides in the self-complementary duplex region of its hairpin structure, (b) exonuclease I (Exo I) that catalyzes the release of FAM from the UDG-induced stretched ssDNA probe, and (c) graphene oxide that quenches the green FAM fluorescence of the intact hairpin DNA probe in the absence of UDG. If Exo I causes the release of FAM from the hairpin DNA probe, the fluorescence peaking at 517 nm is turned off in the absence of UDG but turned on in its presence. The resulting assay has a wide linear range (0.008 to 1 U·mL-1) and a detection limit as low as 0.005 U·mL-1. It has good specificity for UDG over potentially interfering enzymes and gave satisfactory results when applied to biological samples. Conceivably, the method may be used in a wide range of applications such as in diagnosis, drug screening, and in studying the repair of DNA lesions. Graphical abstract Schematic presentation of a fluorometric strategy for detection of the activity of uracil-DNA glycosylase by using on graphene oxide and exonuclease I assisted signal amplification.
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Affiliation(s)
- Mingjian Chen
- School of Life Sciences, Central South University, Changsha, 410013, China
| | - Wenkai Li
- School of Life Sciences, Central South University, Changsha, 410013, China
| | - Changbei Ma
- School of Life Sciences, Central South University, Changsha, 410013, China. .,State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha, 410081, China.
| | - Kefeng Wu
- School of Life Sciences, Central South University, Changsha, 410013, China
| | - Hailun He
- School of Life Sciences, Central South University, Changsha, 410013, China
| | - Kemin Wang
- State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha, 410081, China
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Ultrasensitive impedimetric mercury(II) sensor based on thymine-Hg(II)-thymine interaction and subsequent disintegration of multiple sandwich-structured DNA chains. Mikrochim Acta 2018; 185:555. [PMID: 30465290 DOI: 10.1007/s00604-018-3097-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 11/15/2018] [Indexed: 02/07/2023]
Abstract
An impedimetric method is described for ultrasensitive analysis of mercury(II). It is based on thymine-Hg(II)-thymine interaction which causes the disintegration of multiple-sandwich structured DNA chains. DNA strands were selected that are partially complementary to the T-rich Hg(II)-specific oligonucleotides (MSO). They were immobilized on a gold electrode via Au-S interaction. Next, the MSO and the bridging strands (BS) that can connect adjacent MSOs were alternately attached through layer-by-layer hybridization. Thus, a multiple-sandwich structured interface in created that carries numerous MSOs. This leads to a change-transfer resistance (Rct) values of the electrode-electrolyte interface at faradic electrochemical impedance spectroscopy measurements in the presence of the hexacyanoferrate(II)/(III) redox probe at 0.2 V (vs. Ag/AgCl). If Hg(II) is added to the solution, the MSOs selectively interact with Hg(II) to produce T-Hg(II)-T structures. Hence, the multiple-sandwich hybridization chains become disintegrated, and this causes a decrease in resistivity. The effect can be used to quantify Hg(II) over an analytical range that extends over four orders of magnitude (1 fM to 10 pM), and it has a 0.16 fM limit of detection under optimal conditions. Graphical abstract An electrochemical sensor for femtomolar level detection of Hg2+ is realized on the basis of thymine-Hg2+-thymine interaction which causes disintegration of multiple sandwich DNA hybridization strands.
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Achadu OJ, Revaprasadu N. Microwave-assisted synthesis of thymine-functionalized graphitic carbon nitride quantum dots as a fluorescent nanoprobe for mercury(II). Mikrochim Acta 2018; 185:461. [PMID: 30219975 DOI: 10.1007/s00604-018-3004-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2018] [Accepted: 09/09/2018] [Indexed: 12/16/2022]
Abstract
A microwave-assisted hydrothermal method was employed to prepare thymine-modified graphitic carbon nitride quantum dots (T-gCNQDs) which are shown to be a novel fluorescent nanoprobe for Hg(II). They exhibit excellent optical properties (blue emission with a fluorescence quantum yield of 46%) and water solubility. The incorporation of thymine into the gCNQDs results in an enhancement in photoluminescence properties. It is found that fluorescence, best measured at excitation/emission wavelengths of 350/445 nm, is much more strongly quenched by Hg(II) compared to the thymine-free nanoprobe. The quenching is highly selective even in the presence other metal ions. This is ascribed to the formation of T-Hg(II)-T base complexes. Fluorescence drops linearly in the 1.0 to 500 nM Hg(II) concentration range, and the limit of detection is 0.15 nM. The method was applied to the determination of Hg(II) in spiked samples of tap and pond water. Recoveries were found to be >95%, thus demonstrating the practical applicability of the assay. Graphical abstract A microwave-assisted hydrothermal route was employed to prepare thymine-functionalized graphitic carbon nitride QDs (T-gCNQDs). A selective fluorescence quenching mechanism occurred between T-gCNQDs and Hg(II) due to thymine functionalization. T-gCNQDs was utilized to detect Hg(II) in real samples.
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Affiliation(s)
- Ojodomo J Achadu
- Department of Chemistry, University of Zululand, Private Bag X1001, KwaDlangezwa, 3886, South Africa.
| | - Neerish Revaprasadu
- Department of Chemistry, University of Zululand, Private Bag X1001, KwaDlangezwa, 3886, South Africa
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