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One-click investigation of shape influence of silver nanostructures on SERS performance for sensitive detection of COVID-19. Anal Chim Acta 2022; 1234:340523. [PMCID: PMC9576320 DOI: 10.1016/j.aca.2022.340523] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 10/11/2022] [Accepted: 10/12/2022] [Indexed: 11/20/2022]
Abstract
Sensitive and accurate detection of SARS-CoV-2 methods is meaningful for preventing and controlling the novel coronavirus. The detection techniques supporting portable, onsite, in-time, and online data transfer are urgently needed. Here, we one-click investigated the shape influence of silver nanostructures on SERS performance and their applications in the sensitive detection of SARS-CoV-2. Such investigation is achieved by adjusting multiple parameters (concentration, potential, and time) on the integrated electrochemical array, thus various morphologies (e.g., bulk, dendritic, globular, and spiky) can be one-click synthesized. The SERS performance results indicated that dendritic nanostructures are superior to the other three with an order of magnitude signal enhancement. Such on-electrode dendritic silver substrate also represents high sensitivity (LOD = 7.42 × 10−14 M) and high reproducibility (RSD = 3.67%) toward the SARS-CoV-2 RNA sequence detection. Such approach provides great potentials for rapid diagnosis and prevention of diverse infectious diseases.
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2
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Qiu Q, Ni X, Liu T, Li Z, An X, Chen X. An electrochemical aptasensor for the milk allergen β-lactoglobulin detection based on a target-induced nicking site reconstruction strategy. Analyst 2021; 146:6808-6814. [PMID: 34647930 DOI: 10.1039/d1an01483h] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Food allergy is an immune system reaction to a particular food, milk being the most common one. β-Lactoglobulin (β-Lg) is the main ingredient of milk protein and the main cause of infant milk allergy. On such an occasion, the determination of β-Lg is very important and the electrochemical sensors are a good alternative for this purpose since they are sensitive, selective and inexpensive. In this work, an electrochemical aptasensor was fabricated for the quantitative detection of β-Lg in hypoallergenic formula (HF) milk. A tri-functional hairpin (HP) was designed, which was composed of an aptamer sequence, a nicking site and a DNA sequence (T1). In the absence of β-Lg, the aptamer part hybridized with T1 to form a stable stem-loop structure. However, in the presence of β-Lg, the capture of the aptamer sequence towards β-Lg caused the reconstruction of HP and thus the nicking sites were exposed. Then, the nicking enzyme was activated and T1 could be released, which bound with the end of the hairpin 1-methylene blue (HP1-MB)/HP2-MB conjugation on the Au nanoparticle (AuNP) modified electrode surface. Thus, the insulating property of the electrode was enhanced and the current response of MB decreased, which built the quantitative basis for β-Lg detection. In this way, the proposed aptasensor exhibited a wide linear range of 0.01-100 ng mL-1 and a low detection limit of 5.7 pg mL-1. This aptasensor also displayed high selectivity, reproducibility and stability, and became a promising platform for β-Lg detection in real food samples.
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Affiliation(s)
- Qianying Qiu
- College of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, PR China.
| | - Xiao Ni
- College of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, PR China.
| | - Tianchen Liu
- Nanjing Foreign Language School, Nanjing 210018, PR China
| | - Zening Li
- Nanjing Foreign Language School, Nanjing 210018, PR China
| | - Xinyi An
- Nanjing Foreign Language School, Nanjing 210018, PR China
| | - Xiaojun Chen
- College of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, PR China. .,Jiangsu Key Laboratory of Molecular Biology for Skin Diseases and STIs, Nanjing, 210042, PR China
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Cajigas S, Alzate D, Orozco J. Gold nanoparticle/DNA-based nanobioconjugate for electrochemical detection of Zika virus. Mikrochim Acta 2020; 187:594. [DOI: 10.1007/s00604-020-04568-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 09/25/2020] [Indexed: 12/14/2022]
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4
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Siampour H, Abbasian S, Moshaii A, Omidfar K, Sedghi M, Naderi-Manesh H. Seed-mediated Electrochemically Developed Au Nanostructures with Boosted Sensing Properties: An Implication for Non-enzymatic Glucose Detection. Sci Rep 2020; 10:7232. [PMID: 32350345 PMCID: PMC7190711 DOI: 10.1038/s41598-020-64082-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 02/25/2020] [Indexed: 11/21/2022] Open
Abstract
A new approach has been developed to improve sensing performances of electrochemically grown Au nanostructures (AuNSs) based on the pre-seeding of the electrode. The pre-seeding modification is simply carried out by vacuum thermal deposition of 5 nm thin film of Au on the substrate followed by thermal annealing at 500 °C. The electrochemical growth of AuNSs on the pre-seeded substrates leads to impressive electrochemical responses of the electrode owing to the seeding modification. The dependence of the morphology and the electrochemical properties of the AuNSs on various deposition potentials and times have been investigated. For the positive potentials, the pre-seeding leads to the growth of porous and hole-possess networks of AuNSs on the surface. For the negative potentials, AuNSs with carved stone ball shapes are produced. The superior electrode was achieved from AuNSs developed at 0.1 V for 900 s with pre-seeding modification. The sensing properties of the superior electrode toward glucose detection show a high sensitivity of 184.9 µA mM−1 cm−2, with a remarkable detection limit of 0.32 µM and a wide range of linearity. The excellent selectivity and reproducibility of the sensors propose the current approach as a large-scale production route for non-enzymatic glucose detection.
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Affiliation(s)
- Hossein Siampour
- Department of Physics, Tarbiat Modares University, P.O Box, 14115-175, Tehran, Iran
| | - Sara Abbasian
- School of Physics, Institute for Research in Fundamental Sciences (IPM), P.O. Box, 19395-5531, Tehran, Iran
| | - Ahmad Moshaii
- Department of Physics, Tarbiat Modares University, P.O Box, 14115-175, Tehran, Iran.
| | - Kobra Omidfar
- Biosensor Research Center, Endocrinology and Metabolism Molecular-Cellular Sciences Institute, Tehran University of Medical Science, Tehran, Iran
| | - Mosslim Sedghi
- Department of Nanobiotechnology/Biophysics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, 14115-154, Iran
| | - Hossein Naderi-Manesh
- Department of Nanobiotechnology/Biophysics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, 14115-154, Iran
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Abstract
It is well-known that electrochemical immunosensors have many advantages, including but not limited to high sensitivity, simplicity in application, low-cost production, automated control and potential miniaturization. Due to specific antigen–antibody recognition, electrochemical immunosensors also have provided exceptional possibilities for real-time trace detection of analytical biotargets, which consists of small molecules (such as natural toxins and haptens), macromolecules, cells, bacteria, pathogens or viruses. Recently, the advances in the development of electrochemical immunosensors can be classified into the following directions: the first is using electrochemical detection techniques (voltammetric, amperometric, impedance spectroscopic, potentiometric, piezoelectric, conductometric and alternating current voltammetric) to achieve high sensitivity regarding the electrochemical change of electrochemical signal transduction; the second direction is developing sensor configurations (microfluidic and paper-based platforms, microelectrodes and electrode arrays) for simultaneous multiplex high-throughput analyses; and the last is designing nanostructured materials serving as sensing interfaces to improve sensor sensitivity and selectivity. This chapter introduces the working principle and summarizes the state-of-the-art of electrochemical immunosensors during the past few years with practically relevant details for: (a) metal nanoparticle- and quantum dot-labeled immunosensors; (b) enzyme-labeled immunosensors; and (c) magnetoimmunosensors. The importance of various types of nanomaterials is also thoroughly reviewed to obtain an insight into understanding the theoretical basis and practical orientation for the next generation of diagnostic devices.
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Affiliation(s)
- Hoang Vinh Tran
- School of Chemical Engineering, Hanoi University of Science and Technology (HUST) 1 Dai Co Viet Road Hanoi 100000 Vietnam
| | - Tran Dai Lam
- Graduate University of Science and Technology, Vietnam Academy of Science and Technology 18 Hoang Quoc Viet Hanoi 100000 Vietnam
- Institute for Tropical Technology, Vietnam Academy of Science and Technology 18 Hoang Quoc Viet Hanoi 100000 Vietnam
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Mohammadniaei M, Park C, Min J, Sohn H, Lee T. Fabrication of Electrochemical-Based Bioelectronic Device and Biosensor Composed of Biomaterial-Nanomaterial Hybrid. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1064:263-296. [PMID: 30471039 PMCID: PMC7120487 DOI: 10.1007/978-981-13-0445-3_17] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The field of bioelectronics has paved the way for the development of biochips, biomedical devices, biosensors and biocomputation devices. Various biosensors and biomedical devices have been developed to commercialize laboratory products and transform them into industry products in the clinical, pharmaceutical, environmental fields. Recently, the electrochemical bioelectronic devices that mimicked the functionality of living organisms in nature were applied to the use of bioelectronics device and biosensors. In particular, the electrochemical-based bioelectronic devices and biosensors composed of biomolecule-nanoparticle hybrids have been proposed to generate new functionality as alternatives to silicon-based electronic computation devices, such as information storage, process, computations and detection. In this chapter, we described the recent progress of bioelectronic devices and biosensors based on biomaterial-nanomaterial hybrid.
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Affiliation(s)
- Mohsen Mohammadniaei
- Department of Chemical and Biomolecular Engineering, Sogang University, Seoul, South Korea
| | - Chulhwan Park
- Department of Chemical Engineering, Kwangwoon University, Seoul, South Korea
| | - Junhong Min
- School of Integrative Engineering Chung-Ang University, Seoul, South Korea
| | - Hiesang Sohn
- Department of Chemical Engineering, Kwangwoon University, Seoul, South Korea.
| | - Taek Lee
- Department of Chemical Engineering, Kwangwoon University, Seoul, South Korea.
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A sandwich-type photoelectrochemical immunosensor for NT-pro BNP detection based on F-Bi2WO6/Ag2S and GO/PDA for signal amplification. Biosens Bioelectron 2019; 131:299-306. [DOI: 10.1016/j.bios.2019.02.029] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 01/27/2019] [Accepted: 02/11/2019] [Indexed: 12/19/2022]
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Abstract
The development of biosensors for a range of analytes from small molecules to proteins to oligonucleotides is an intensely active field. Detection methods based on electrochemistry or on localized surface plasmon responses have advanced through using nanostructured electrodes prepared by electrodeposition, which is capable of preparing a wide range of different structures. Supported nanoparticles can be prepared by electrodeposition through applying fixed potentials, cycling potentials, and fixed current methods. Nanoparticle sizes, shapes, and surface densities can be controlled, and regular structures can be prepared by electrodeposition through templates. The incorporation of multiple nanomaterials into composite films can take advantage of the superior and potentially synergistic properties of each component. Nanostructured electrodes can provide supports for enzymes, antibodies, or oligonucleotides for creating sensors against many targets in areas such as genomic analysis, the detection of protein antigens, or the detection of small molecule metabolites. Detection can also be performed using electrochemical methods, and the nanostructured electrodes can greatly enhance electrochemical responses by carefully designed schemes. Biosensors based on electrodeposited nanostructures can contribute to the advancement of many goals in bioanalytical and clinical chemistry.
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Hasanzadeh M, Babaie P, Mokhtarzadeh A, Hajizadeh N, Mahboob S. A novel DNA based bioassay toward ultrasensitive detection of Brucella using gold nanoparticles supported histidine: A new platform for the assay of bacteria in the cultured and human biofluids with and without polymerase chain reactions (PCR). Int J Biol Macromol 2018; 120:422-430. [DOI: 10.1016/j.ijbiomac.2018.08.092] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 08/17/2018] [Accepted: 08/18/2018] [Indexed: 11/15/2022]
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Cross-linked chitosan/thiolated graphene quantum dots as a biocompatible polysaccharide towards aptamer immobilization. Int J Biol Macromol 2018; 123:1091-1105. [PMID: 30458193 DOI: 10.1016/j.ijbiomac.2018.11.139] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 11/09/2018] [Accepted: 11/14/2018] [Indexed: 01/11/2023]
Abstract
Chitosan has a number of commercial and possible biomedical uses. Chitosan as a polysaccharide is a bioactive polymer with a variety of applications due to its functional properties such as antibacterial activity, non-toxicity, ease of modification, and biodegradability. In this work, cross-linked chitosan/thiolated graphene quantum dot as a biocompatible polysaccharide was modified by gold nanoparticle and used for immobilization of ractopamine (RAC) aptamer. A highly specific DNA-aptamer (5'-SH-AAAAAGTGCGGGC-3'), selected to RAC was immobilized onto thiolated graphene quantum dots (GQDs)-chitosan (CS) nanocomposite modified by gold nanostructures (Au NSs) and used for quantification of RAC. Different shapes of gold nanostructures with various sizes from zero-dimensional nanoparticles to spherical structures were prepared by one-step template-assistant green electrodeposition method. Fully electrochemical methodology was used to prepare a new transducer on a glassy carbon surface which provided a high surface area to immobilize a high amount of the aptamer. Therefore, a label free electrochemical (EC) apta-assay for ultrasensitive detection of RAC was developed. A special immobilization media consisting of Au NSs/GQDs-CS/Cysteamine (CysA) was utilized to improve conductivity and performance of the biosensor. The RAC aptamer was attached on the Au NSs of the composite membrane via AuS bond. The fabrication process of the EC aptamer based assay was characterized by some electrochemical techniques. The peak currents obtained by differential pulse voltammetry decreased linearly with the increasing of RAC concentrations and the apta-assay responds approximately over a wide dynamic range of RAC concentration from 0.0044 fM to 19.55 μM. The low limit of quantification was 0.0044 fM.
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11
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Double determination of long noncoding RNAs from lung cancer via multi-amplified electrochemical genosensor at sub-femtomole level. Biosens Bioelectron 2018; 113:116-123. [DOI: 10.1016/j.bios.2018.04.062] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2018] [Revised: 04/28/2018] [Accepted: 04/30/2018] [Indexed: 12/13/2022]
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12
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Hasanzadeh M, Baghban HN, Shadjou N, Mokhtarzadeh A. Ultrasensitive electrochemical immunosensing of tumor suppressor protein p53 in unprocessed human plasma and cell lysates using a novel nanocomposite based on poly-cysteine/graphene quantum dots/gold nanoparticle. Int J Biol Macromol 2018; 107:1348-1363. [DOI: 10.1016/j.ijbiomac.2017.11.006] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 11/01/2017] [Accepted: 11/02/2017] [Indexed: 10/18/2022]
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Mohammadniaei M, Lee T, Yoon J, Lee D, Choi JW. Electrochemical nucleic acid detection based on parallel structural dsDNA/recombinant azurin hybrid. Biosens Bioelectron 2017; 98:292-298. [PMID: 28697440 PMCID: PMC7125781 DOI: 10.1016/j.bios.2017.07.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2017] [Revised: 06/22/2017] [Accepted: 07/04/2017] [Indexed: 02/07/2023]
Abstract
Several challenges remained to fabricate a molecular-level nucleic acid biosensor such as surface immobilization control, single mismatch detection and low current response. To overcome those issues, for the first time, authors presented a novel parallel structural dsDNA/recombinant azurin (PSD/rAzu) hybrid structure for the general nucleic acid detection. The PSD was designed and introduced by the optimized 8 Ag+ ions to have greater conductivity than the canonical dsDNA, and conjugated with rAzu to develop a general platform for electrochemical detection of miRNAs and viral DNAs with high reproducibility and ultra-sensitivity towards single base pair mutation. Thanks to the bifunctional rAzu as the selective spacer and electrochemical signal mediator, in the presence of the target strand, the imperfect PSD switched rapidly to the upright position where the Ag+ ions intercalated between C-C mismatches of dsDNAs at the top of each structure brought further from the electrode surface resulting in a significant electrochemical signal drop of the Ag+ ions. The charge transfer (CT) mechanism across the hybrid structure was simply clarified on the basis of the redox potential location of the species. The electrical conductivity of DNAs were measured using scanning tunneling spectroscopy (STS) at the molecular scale and cyclic voltammetry (CV) technique based on the reduction of Ag+ ion. The proposed PSD/rAzu hybrid structure with a great capability of single mutation recognition and miRNA expression level profiling in cancer cells holds a very promising platform to be studied for further development of various kinds of nanoscale biosensors, bioelectronic devices.
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Affiliation(s)
- Mohsen Mohammadniaei
- Department of Chemical and Biomolecular Engineering, Sogang University, 35 Baekbeom-ro (Sinsu-dong), Mapo-gu, Seoul 121-742, Republic of Korea
| | - Taek Lee
- Department of Chemical and Biomolecular Engineering, Sogang University, 35 Baekbeom-ro (Sinsu-dong), Mapo-gu, Seoul 121-742, Republic of Korea; Department of Chemical Engineering, Kwangwoon University, 20 Kwangwoon-Ro, Nowon-Gu, Seoul 01897, Republic of Korea
| | - Jinho Yoon
- Department of Chemical and Biomolecular Engineering, Sogang University, 35 Baekbeom-ro (Sinsu-dong), Mapo-gu, Seoul 121-742, Republic of Korea
| | - Donghyun Lee
- School of Integrative Engineering Chung-Ang University, Heukseok-dong, Dongjak-gu, Seoul 156-756, Republic of Korea.
| | - Jeong-Woo Choi
- Department of Chemical and Biomolecular Engineering, Sogang University, 35 Baekbeom-ro (Sinsu-dong), Mapo-gu, Seoul 121-742, Republic of Korea.
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14
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Hasanzadeh M, Razmi N, Mokhtarzadeh A, Shadjou N, Mahboob S. Aptamer based assay of plated-derived grow factor in unprocessed human plasma sample and MCF-7 breast cancer cell lysates using gold nanoparticle supported α-cyclodextrin. Int J Biol Macromol 2017; 108:69-80. [PMID: 29180051 DOI: 10.1016/j.ijbiomac.2017.11.149] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 11/22/2017] [Accepted: 11/23/2017] [Indexed: 01/06/2023]
Abstract
Platelet-derived growth factor (PDGF), a protein biomarker, is directly involved in many cell transformation processes, such as tumor growth and progression. Elevation platelet-derived growth factor (PDGF-BB) concentration in plasma could indicate the accelerating growth of metastatic breast tumors and angiogenesis. The development of an apta-assay for detection of PDGF-BB in is presented in this work. A highly specific DNA-aptamer, selected to PDGF-BB was immobilized onto a gold nanoparticles supported α-cyclodextrin and electrochemical measurements were performed in a solution containing the phosphate buffer solution with physiological pH. Variety of shapes of gold nanostructures with different sizes from zero-dimensional nanoparticles to spherical structures were prepared by one-step template (α-cyclodextrin)-assistant green electrodeposition method. Fully electrochemical methodology was used to prepare a new transducer on a gold surface which provided a high surface area to immobilize a high amount of the aptamer. The surface morphology of electrode was characterized by high-resolution field emission scanning electron microscope (FE-SEM) and energy dispersive spectroscopy (EDX). The prepared aptasensors represented different electrochemical activities toward the redox processes of PDGF-BB attributing to the size and shape of the gold nanoparticles. The aptasensor was employed for the detection of PDGF using square wave voltammetry (SWV) and Cyclic voltammetry (CV) techniques. Under optimized condition the calibration curve for PDGF-BB was linear in 0.52-1.52nM with low limit of quantification of 0.52nM. Also, under the optimized experimental conditions, the proposed aptasensor of GNPs-cubic-α-CD-Apt-Au electrode exhibited excellent analytical performance for MCF-7 cells determination, ranging from 328 TO 593 cells mL-1 with low limit of quantification of 328 cells mL-1. As a result, the electrochemical aptasensor was able to detect cancer-related targets in unprocessed human plasma samples.
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Affiliation(s)
- Mohammad Hasanzadeh
- Drug Applied Research Center, TabrizUniversity of Medical Sciences, Tabriz 51664, Iran.
| | - Nasrin Razmi
- Pharmaceutical Analysis Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Ahad Mokhtarzadeh
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Nasrin Shadjou
- Department of Nanochemistry, Nano Technology Research Center, Urmia University, Urmia 57154, Iran; Department of Nano Technology, Faculty of Science, Urmia University, Urmia 57154, Iran
| | - Soltanali Mahboob
- Department of Biochemistry, Higher Education Institute of Rab-Rashid, Tabriz, Iran
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15
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Malekzad H, Hasanzadeh M, Shadjou N, Jouyban A. Highly sensitive immunosensing of prostate specific antigen using poly cysteine caped by graphene quantum dots and gold nanoparticle: A novel signal amplification strategy. Int J Biol Macromol 2017; 105:522-532. [PMID: 28711617 DOI: 10.1016/j.ijbiomac.2017.07.069] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2017] [Revised: 07/06/2017] [Accepted: 07/11/2017] [Indexed: 01/24/2023]
Abstract
A mediator-free electrochemical immunosensor for quantitation of prostate specific antigen (PSA) based on dual signal amplification strategy was fabricated. In this work, PSA-antibody (anti-PSA) was immobilized onto a green and biocompatible nanocomposite containing poly l-cysteine (P-Cys) as conductive matrix and graphene quantum dots (GQDs)/gold nanoparticles (GNPs) as dual signal amplification elements. Therefore, a novel multilayer film based on P-Cys, GQDs, and GNPs was exploited to develop a highly sensitive amperometric immunosensor for detection of PSA. Fully electrochemical methodology was used to prepare a new transducer on a gold surface which provided a high surface area to immobilize a high amount of the anti-PSA. Importantly, GNPs prepared by soft template synthesized method lead to compact morphology was achieved. The surface morphology of electrode surface was characterized by high-resolution field emission scanning electron microscope (FE-SEM) and energy dispersive spectroscopy (EDX). Chemical compositions of the gold nanoparticles were analysed by an EDX. The immunosensor was employed for the detection of PSA in physiological pH. Under optimized condition the calibration curve for PSA concentration was linear up to 2-9pgmL-1 with lower limit of quantification of 1.8pgmL-1.
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Affiliation(s)
- Hediyeh Malekzad
- Pharmaceutical Analysis Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mohammad Hasanzadeh
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
| | - Nasrin Shadjou
- Department of Nanochemistry, Nano Technology Research Center, Urmia University, Urmia 57154, Iran; Department of Nano Technology, Faculty of Science, Urmia University, Urmia 57154, Iran
| | - Abolghasem Jouyban
- Pharmaceutical Analysis Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Kimia Idea Pardaz Azarbayjan (KIPA) Science Based Company, Tabriz University of Medical Sciences, Tabriz 51664, Iran
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16
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Shi L, Li Y, Rong X, Wang Y, Ding S. Facile fabrication of a novel 3D graphene framework/Bi nanoparticle film for ultrasensitive electrochemical assays of heavy metal ions. Anal Chim Acta 2017; 968:21-29. [DOI: 10.1016/j.aca.2017.03.013] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 01/24/2017] [Accepted: 03/01/2017] [Indexed: 12/12/2022]
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17
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Shi L, Wang Y, Chu Z, Yin Y, Jiang D, Luo J, Ding S, Jin W. A highly sensitive and reusable electrochemical mercury biosensor based on tunable vertical single-walled carbon nanotubes and a target recycling strategy. J Mater Chem B 2017; 5:1073-1080. [DOI: 10.1039/c6tb02658c] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Conformational regulation of SAMs was proposed for controlled growth of v-SWCNTs, which were employed to construct a high-performance mercury biosensor using a target recycling strategy.
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Affiliation(s)
- Lei Shi
- State Key Laboratory of Lake Science and Environment
- Nanjing Institute of Geography and Limnology
- Chinese Academy of Sciences
- Nanjing 210008
- P. R. China
| | - Yan Wang
- State Key Laboratory of Lake Science and Environment
- Nanjing Institute of Geography and Limnology
- Chinese Academy of Sciences
- Nanjing 210008
- P. R. China
| | - Zhenyu Chu
- State Key Laboratory of Materials-Oriented Chemical Engineering
- College of Chemical Engineering
- Nanjing Tech University
- Nanjing 210009
- P. R. China
| | - Yu Yin
- School of Environmental and Chemical Engineering
- Jiangsu University of Science and Technology
- Zhenjiang 212003
- P. R. China
| | - Danfeng Jiang
- State Key Laboratory of Materials-Oriented Chemical Engineering
- College of Chemical Engineering
- Nanjing Tech University
- Nanjing 210009
- P. R. China
| | - Jingyi Luo
- State Key Laboratory of Materials-Oriented Chemical Engineering
- College of Chemical Engineering
- Nanjing Tech University
- Nanjing 210009
- P. R. China
| | - Shiming Ding
- State Key Laboratory of Lake Science and Environment
- Nanjing Institute of Geography and Limnology
- Chinese Academy of Sciences
- Nanjing 210008
- P. R. China
| | - Wanqin Jin
- State Key Laboratory of Materials-Oriented Chemical Engineering
- College of Chemical Engineering
- Nanjing Tech University
- Nanjing 210009
- P. R. China
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18
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Shi L, Wang Y, Ding S, Chu Z, Yin Y, Jiang D, Luo J, Jin W. A facile and green strategy for preparing newly-designed 3D graphene/gold film and its application in highly efficient electrochemical mercury assay. Biosens Bioelectron 2016; 89:871-879. [PMID: 27818041 DOI: 10.1016/j.bios.2016.09.104] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 09/27/2016] [Accepted: 09/28/2016] [Indexed: 02/07/2023]
Abstract
In this work, we report a facile and green strategy for in situ and one step preparation of a novel 3D graphene/gold (G/Au) film. Triggering with unique driving force from hydrothermal growth, a 3D interlaced graphene framework with hierarchically porous structures was directly attached on a gold substrate pretreated with a self-assembled monolayer. Simultaneously, highly dispersive Au nanoparticles with tunable morphologies were anchored on the framework utilizing generated graphene as an endogenous reductant. Newly-designed 3D G/Au film possessed excellent properties of significantly large specific area, good electrical conductivity, high structure stability and substrate binding strength, etc. As a paradigm, an electrochemical Hg2+ biosensor was constructed on 3D G/Au film, in which an exonuclease III-assisted target recycling was introduced. Impressively, an ultralow detection limit of 50 aM (S/N=3), a wide linear range from 0.1 fM to 0.1μM, a high selectivity and a good reliability for Hg2+ assay in real water and serum samples were realized using prepared biosensor. It is highly envisioned that this work opens the door towards simply fabricating varying types of 3D graphene based hybrid films, and such G/Au film will have widespread applications in electroanalysis and electrocatalysis.
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Affiliation(s)
- Lei Shi
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, PR China
| | - Yan Wang
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, PR China
| | - Shiming Ding
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, PR China.
| | - Zhenyu Chu
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 210009, PR China
| | - Yu Yin
- School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, PR China
| | - Danfeng Jiang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 210009, PR China
| | - Jingyi Luo
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 210009, PR China
| | - Wanqin Jin
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 210009, PR China
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19
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Su S, Wu Y, Zhu D, Chao J, Liu X, Wan Y, Su Y, Zuo X, Fan C, Wang L. On-Electrode Synthesis of Shape-Controlled Hierarchical Flower-Like Gold Nanostructures for Efficient Interfacial DNA Assembly and Sensitive Electrochemical Sensing of MicroRNA. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2016; 12:3794-3801. [PMID: 27305644 DOI: 10.1002/smll.201601066] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Indexed: 06/06/2023]
Abstract
The performance for biomolecular detection is closely associated with the interfacial structure of a biosensor, which profoundly affects both thermodynamics and kinetics of the assembly, binding and signal transduction of biomolecules. Herein, it is reported on a one-step and template-free on-electrode synthesis method for making shape-controlled gold nanostructures on indium tin oxide substrates, which provide an electrochemical sensing platform for ultrasensitive detection of nucleic acids. Thus-prepared hierarchical flower-like gold nanostructures (HFGNs) possess large surface area that can readily accommodate the assembly of DNA probes for subsequent hybridization detection. It is found that the sensitivity for electrochemical DNA sensing is critically dependent on the morphology of HFGNs. By using this new strategy, a highly sensitive electrochemical biosensor is developed for label-free detection of microRNA-21 (miRNA-21), a biomarker for lung cancers. Importantly, it is demonstrated that this biosensor can be employed to measure the miRNA-21 expression level from human lung cancer cell (A549) lysates and worked well in 100% serum, suggesting its potential for applications in clinical diagnosis and a wide range of bioanalysis.
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Affiliation(s)
- Shao Su
- Key Laboratory for Organic Electronics & Information Displays (KLOEID), Institute of Advanced Materials (IAM), National Synergistic Innovation Center for Advanced Materials (SICAM), Nanjing University of Posts & Telecommunications, 9 Wenyuan Road, Nanjing, 210023, China
| | - Yan Wu
- Key Laboratory for Organic Electronics & Information Displays (KLOEID), Institute of Advanced Materials (IAM), National Synergistic Innovation Center for Advanced Materials (SICAM), Nanjing University of Posts & Telecommunications, 9 Wenyuan Road, Nanjing, 210023, China
| | - Dan Zhu
- Key Laboratory for Organic Electronics & Information Displays (KLOEID), Institute of Advanced Materials (IAM), National Synergistic Innovation Center for Advanced Materials (SICAM), Nanjing University of Posts & Telecommunications, 9 Wenyuan Road, Nanjing, 210023, China
| | - Jie Chao
- Key Laboratory for Organic Electronics & Information Displays (KLOEID), Institute of Advanced Materials (IAM), National Synergistic Innovation Center for Advanced Materials (SICAM), Nanjing University of Posts & Telecommunications, 9 Wenyuan Road, Nanjing, 210023, China
| | - Xingfen Liu
- Key Laboratory for Organic Electronics & Information Displays (KLOEID), Institute of Advanced Materials (IAM), National Synergistic Innovation Center for Advanced Materials (SICAM), Nanjing University of Posts & Telecommunications, 9 Wenyuan Road, Nanjing, 210023, China
| | - Ying Wan
- School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China
| | - Yan Su
- School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China
| | - Xiaolei Zuo
- Division of Physical Biology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, 201800, China
| | - Chunhai Fan
- Key Laboratory for Organic Electronics & Information Displays (KLOEID), Institute of Advanced Materials (IAM), National Synergistic Innovation Center for Advanced Materials (SICAM), Nanjing University of Posts & Telecommunications, 9 Wenyuan Road, Nanjing, 210023, China
- Division of Physical Biology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, 201800, China
| | - Lianhui Wang
- Key Laboratory for Organic Electronics & Information Displays (KLOEID), Institute of Advanced Materials (IAM), National Synergistic Innovation Center for Advanced Materials (SICAM), Nanjing University of Posts & Telecommunications, 9 Wenyuan Road, Nanjing, 210023, China
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20
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Nordin N, Yusof NA, Abdullah J, Radu S, Hushiarian R. Sensitive detection of multiple pathogens using a single DNA probe. Biosens Bioelectron 2016; 86:398-405. [PMID: 27414245 DOI: 10.1016/j.bios.2016.06.077] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Revised: 06/22/2016] [Accepted: 06/26/2016] [Indexed: 10/21/2022]
Abstract
A simple but promising electrochemical DNA nanosensor was designed, constructed and applied to differentiate a few food-borne pathogens. The DNA probe was initially designed to have a complementary region in Vibrio parahaemolyticus (VP) genome and to make different hybridization patterns with other selected pathogens. The sensor was based on a screen printed carbon electrode (SPCE) modified with polylactide-stabilized gold nanoparticles (PLA-AuNPs) and methylene blue (MB) was employed as the redox indicator binding better to single-stranded DNA. The immobilization and hybridization events were assessed using differential pulse voltammetry (DPV). The fabricated biosensor was able to specifically distinguish complementary, non-complementary and mismatched oligonucleotides. DNA was measured in the range of 2.0×10(-9)-2.0×10(-13)M with a detection limit of 5.3×10(-12)M. The relative standard deviation for 6 replications of DPV measurement of 0.2µM complementary DNA was 4.88%. The fabricated DNA biosensor was considered stable and portable as indicated by a recovery of more than 80% after a storage period of 6 months at 4-45°C. Cross-reactivity studies against various food-borne pathogens showed a reliably sensitive detection of VP.
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Affiliation(s)
- Noordiana Nordin
- Institute of Advanced Technology, Universiti Putra Malaysia, UPM, 43400 Serdang, Selangor, Malaysia; Food Safety Research Centre, Faculty of Food Science and Technology, Universiti Putra Malaysia, UPM, 43400 Serdang, Selangor, Malaysia
| | - Nor Azah Yusof
- Institute of Advanced Technology, Universiti Putra Malaysia, UPM, 43400 Serdang, Selangor, Malaysia; Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, UPM, 43400 Serdang, Selangor, Malaysia.
| | - Jaafar Abdullah
- Institute of Advanced Technology, Universiti Putra Malaysia, UPM, 43400 Serdang, Selangor, Malaysia; Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, UPM, 43400 Serdang, Selangor, Malaysia
| | - Son Radu
- Food Safety Research Centre, Faculty of Food Science and Technology, Universiti Putra Malaysia, UPM, 43400 Serdang, Selangor, Malaysia
| | - Roozbeh Hushiarian
- La Trobe Institute for Molecular Science, La Trobe University, Victoria 3086, Australia.
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21
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In-situ fabrication of well-distributed gold nanocubes on thiol graphene as a third-generation biosensor for ultrasensitive glucose detection. Electrochim Acta 2015. [DOI: 10.1016/j.electacta.2015.06.123] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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22
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Zhou H, Jia H, Zhang A, Zhang L, Jia C, Zheng L. The interconversion between gold nanostars and gold nanodendrites controlled via temperature and the concentration of sodium dodecyl sulfonate. J Mol Liq 2015. [DOI: 10.1016/j.molliq.2015.04.028] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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23
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Shi L, Chu Z, Liu Y, Jin W. Facile fabrication of a three-dimensional gold nanowire array for high-performance electrochemical sensing. J Mater Chem B 2015; 3:3134-3140. [DOI: 10.1039/c5tb00266d] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
A three-dimensional gold nanowire array (3D GNA) was successfully prepared with a facile template-assisted approach, in order to construct an ultrasensitive electrochemical biosensor.
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Affiliation(s)
- Lei Shi
- State Key Laboratory of Materials-Oriented Chemical Engineering
- College of Chemistry and Chemical Engineering
- Nanjing Tech. University
- Nanjing 210009
- P. R. China
| | - Zhenyu Chu
- State Key Laboratory of Materials-Oriented Chemical Engineering
- College of Chemistry and Chemical Engineering
- Nanjing Tech. University
- Nanjing 210009
- P. R. China
| | - Yu Liu
- State Key Laboratory of Materials-Oriented Chemical Engineering
- College of Chemistry and Chemical Engineering
- Nanjing Tech. University
- Nanjing 210009
- P. R. China
| | - Wanqin Jin
- State Key Laboratory of Materials-Oriented Chemical Engineering
- College of Chemistry and Chemical Engineering
- Nanjing Tech. University
- Nanjing 210009
- P. R. China
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24
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Sharma R, Sinha RK, Agrawal VV. Mediator-free total cholesterol estimation using a bi-enzyme functionalized nanostructured gold electrode. RSC Adv 2015. [DOI: 10.1039/c5ra03053f] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A one-step electrochemical route for the synthesis, functionalization and deposition of Au nanostructures and for the bi-enzyme functionalization of a Au electrode has been proposed.
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Affiliation(s)
- Rachna Sharma
- Biomedical Instrumentation Section
- National Physical Laboratory
- New Delhi 110012
- India
- Department of Applied Physics
| | - R. K. Sinha
- Department of Applied Physics
- Delhi Technological University
- New Delhi 110042
- India
| | - Ved Varun Agrawal
- Biomedical Instrumentation Section
- National Physical Laboratory
- New Delhi 110012
- India
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25
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Bedford EE, Boujday S, Pradier CM, Gu FX. Nanostructured and spiky gold in biomolecule detection: improving binding efficiencies and enhancing optical signals. RSC Adv 2015. [DOI: 10.1039/c4ra13544j] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Nanostructured gold can improve the ability to detect biomolecules.
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Affiliation(s)
- E. E. Bedford
- Sorbonne Universités
- UPMC University Paris 6
- UMR CNRS 7197
- Laboratoire de Réactivité de Surface
- F75005 Paris
| | - S. Boujday
- Sorbonne Universités
- UPMC University Paris 6
- UMR CNRS 7197
- Laboratoire de Réactivité de Surface
- F75005 Paris
| | - C.-M. Pradier
- Sorbonne Universités
- UPMC University Paris 6
- UMR CNRS 7197
- Laboratoire de Réactivité de Surface
- F75005 Paris
| | - F. X. Gu
- Department of Chemical Engineering
- University of Waterloo
- Waterloo
- Canada
- Waterloo Institute for Nanotechnology
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26
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Zhou YG, Wan Y, Sage AT, Poudineh M, Kelley SO. Effect of microelectrode structure on electrocatalysis at nucleic acid-modified sensors. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:14322-14328. [PMID: 25377873 DOI: 10.1021/la502990s] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The electrochemical detection of nucleic acids using an electrocatalytic reporter system and nanostructured microelectrodes is a powerful approach to ultrasensitive biosensing. In this report we systematically study for the first time the behavior of an electrocatalytic reporter system at nucleic acid-modified electrodes with varying structures and sizes. [Ru(NH3)6](3+) is used as a primary electron acceptor that is electrostatically attracted to nucleic acid-modified electrodes, and [Fe(CN)6](3-) is introduced into the redox system as a secondary electron acceptor to regenerate Ru(3+) after electrochemical reduction. We found that the electrode structure has strong impact on mass transport and electron-transfer kinetics, with structures of specific dimensions yielding much higher electrochemical signals and catalytic efficiencies. The electrocatalytic signals obtained when gold sensors were electrodeposited in both circular and linear apertures were studied, and the smallest structures plated in linear apertures were found to exhibit the best performance with high current densities and turnover rates. This study provides important information for optimal assay performance and insights for the future design and fabrication of high performance biomolecular assays.
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Affiliation(s)
- Yi-Ge Zhou
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, ‡Department of Biochemistry, Faculty of Medicine, and §Department of Electrical and Computer Engineering, University of Toronto , Toronto, ON M5S 3M2, Canada
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27
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Shi L, Chu Z, Liu Y, Jin W, Chen X. An ultrasensitive electrochemical sensing platform for Hg2+ based on a density controllable metal-organic hybrid microarray. Biosens Bioelectron 2014; 54:165-70. [DOI: 10.1016/j.bios.2013.10.074] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Revised: 10/30/2013] [Accepted: 10/31/2013] [Indexed: 11/28/2022]
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28
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Zhang P, Wang S. Designing Fractal Nanostructured Biointerfaces for Biomedical Applications. Chemphyschem 2014; 15:1550-61. [DOI: 10.1002/cphc.201301230] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Indexed: 01/23/2023]
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29
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Shi L, Chu Z, Liu Y, Peng J, Jin W. Three-dimensional porous microarray of gold modified electrode for ultrasensitive and simultaneous assay of various cancer biomarkers. J Mater Chem B 2014; 2:2658-2665. [DOI: 10.1039/c4tb00016a] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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30
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Shi L, Chu Z, Dong X, Jin W, Dempsey E. A highly oriented hybrid microarray modified electrode fabricated by a template-free method for ultrasensitive electrochemical DNA recognition. NANOSCALE 2013; 5:10219-10225. [PMID: 24061929 DOI: 10.1039/c3nr03097k] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Highly oriented growth of a hybrid microarray was realized by a facile template-free method on gold substrates for the first time. The proposed formation mechanism involves an interfacial structure-directing force arising from self-assembled monolayers (SAMs) between gold substrates and hybrid crystals. Different SAMs and variable surface coverage of the assembled molecules play a critical role in the interfacial directing forces and influence the morphologies of hybrid films. A highly oriented hybrid microarray was formed on the highly aligned and vertical SAMs of 1,4-benzenedithiol molecules with rigid backbones, which afforded an intense structure-directing power for the oriented growth of hybrid crystals. Additionally, the density of the microarray could be adjusted by controlling the surface coverage of assembled molecules. Based on the hybrid microarray modified electrode with a large specific area (ca. 10 times its geometrical area), a label-free electrochemical DNA biosensor was constructed for the detection of an oligonucleotide fragment of the avian flu virus H5N1. The DNA biosensor displayed a significantly low detection limit of 5 pM (S/N = 3), a wide linear response from 10 pM to 10 nM, as well as excellent selectivity, good regeneration and high stability. We expect that the proposed template-free method can provide a new reference for the fabrication of a highly oriented hybrid array and the as-prepared microarray modified electrode will be a promising paradigm in constructing highly sensitive and selective biosensors.
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Affiliation(s)
- Lei Shi
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemistry and Chemical Engineering, Nanjing University of Technology, Nanjing 210009, P. R. China.
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