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Zinc oxide-ternary heterostructure Mn3O4/ZnO/Eu2O3 nanocomposites were successfully prepared via waste curd as fuel by a facile one-pot combustion procedure. The fabricated heterostructures were characterized utilizing XRD, UV–Visible, FT-IR, FE-SEM, HRTEM and EDX analysis. The photocatalytic degradation efficacy of the synthesized ternary nanocomposite was evaluated utilizing model organic pollutants of methylene blue (MB) and methyl orange (MO) in water as examples of cationic dyes and anionic dyes, respectively, under natural solar irradiation. The effect of various experimental factors, viz. the effect of a light source, catalyst dosage, irradiation time, pH of dye solution and dye concentration on the photodegradation activity, was systematically studied. The ternary Mn3O4/ZnO/Eu2O3 photocatalyst exhibited excellent MB and MO degradation activity of 98% and 96%, respectively, at 150 min under natural sunlight irradiation. Experiments further conclude that the fabricated nanocomposite exhibits pH-dependent photocatalytic efficacy, and for best results, concentrations of dye and catalysts have to be maintained in a specific range. The prepared photocatalysts are exemplary and could be employed for wastewater handling and several ecological applications.
Jayachamarajapura Shubha; Haralahalli Savitha; Syed Adil; Mujeeb Khan; Mohammad Hatshan; Kiran Kavalli; Baji Shaik. Straightforward Synthesis of Mn3O4/ZnO/Eu2O3-Based Ternary Heterostructure Nano-Photocatalyst and Its Application for the Photodegradation of Methyl Orange and Methylene Blue Dyes. Molecules 2021, 26, 4661 .
AMA StyleJayachamarajapura Shubha, Haralahalli Savitha, Syed Adil, Mujeeb Khan, Mohammad Hatshan, Kiran Kavalli, Baji Shaik. Straightforward Synthesis of Mn3O4/ZnO/Eu2O3-Based Ternary Heterostructure Nano-Photocatalyst and Its Application for the Photodegradation of Methyl Orange and Methylene Blue Dyes. Molecules. 2021; 26 (15):4661.
Chicago/Turabian StyleJayachamarajapura Shubha; Haralahalli Savitha; Syed Adil; Mujeeb Khan; Mohammad Hatshan; Kiran Kavalli; Baji Shaik. 2021. "Straightforward Synthesis of Mn3O4/ZnO/Eu2O3-Based Ternary Heterostructure Nano-Photocatalyst and Its Application for the Photodegradation of Methyl Orange and Methylene Blue Dyes." Molecules 26, no. 15: 4661.
Biofilms not only protect bacteria and Candida species from antibiotics, but they also promote the emergence of drug-resistant strains, making eradication more challenging. As a result, novel antimicrobial agents to counteract biofilm formation are desperately needed. In this study, Terminalia catappa leaf extract (TCE) was used to optimize the TCE-capped silver nanoparticles (TCE-AgNPs) via a one-pot single-step method. Varied concentrations of TCE have yielded different sized AgNPs. The physico-chemical characterization of TCE-AgNPs using UV-Vis, SEM, TEM, FTIR, and Raman spectroscopy have confirmed the formation of nanostructures, their shape and size and plausible role of TCE bio-active compounds, most likely involved in the synthesis as well as stabilization of NPs, respectively. TCE-AgNPs have been tested for antibiofilm and antimicrobial activity against multidrug-resistant Pseudomonas aeruginosa (MDR-PA), methicillin-resistant Staphylococcus aureus (MRSA), and Candida albicans using various microbiological protocols. TCE-Ag-NPs−3 significantly inhibits biofilm formation of MDR-PA, MRSA, and C. albicans by 73.7, 69.56, and 63.63%, respectively, at a concentration of 7.8 µg/mL, as determined by crystal violet microtiter assay. Furthermore, SEM micrograph shows that TCE-AgNPs significantly inhibit the colonization and adherence of biofilm forming cells; individual cells with loss of cell wall and membrane integrity were also observed, suggesting that the biofilm architecture and EPS matrix were severely damaged. Moreover, TEM and SEM images showed that TCE-AgNPs brutally damaged the cell wall and membranes of MDR-PA, MRSA, and C. albicans. Additionally, extreme ultrastructural changes such as deformation, disintegration, and separation of cell wall and membrane from the cells, have also been observed, indicating significant loss of membrane and cell wall integrity, which eventually led to cell death. Overall, the research revealed a simple, environmentally friendly, and low-cost method for producing colloidal TCE-AgNPs with promising applications in advanced clinical settings against broad-spectrum biofilm-forming antibiotic-resistant bacteria and candida strains.
Mohammad Ansari; Abul Kalam; Abdullah Al-Sehemi; Mohammad Alomary; Sami AlYahya; Mohammad Aziz; Shekhar Srivastava; Saad Alghamdi; Sultan Akhtar; Hussain Almalki; Syed Adil; Mujeeb Khan; Mohammad Hatshan. Counteraction of Biofilm Formation and Antimicrobial Potential of Terminalia catappa Functionalized Silver Nanoparticles against Candida albicans and Multidrug-Resistant Gram-Negative and Gram-Positive Bacteria. Antibiotics 2021, 10, 725 .
AMA StyleMohammad Ansari, Abul Kalam, Abdullah Al-Sehemi, Mohammad Alomary, Sami AlYahya, Mohammad Aziz, Shekhar Srivastava, Saad Alghamdi, Sultan Akhtar, Hussain Almalki, Syed Adil, Mujeeb Khan, Mohammad Hatshan. Counteraction of Biofilm Formation and Antimicrobial Potential of Terminalia catappa Functionalized Silver Nanoparticles against Candida albicans and Multidrug-Resistant Gram-Negative and Gram-Positive Bacteria. Antibiotics. 2021; 10 (6):725.
Chicago/Turabian StyleMohammad Ansari; Abul Kalam; Abdullah Al-Sehemi; Mohammad Alomary; Sami AlYahya; Mohammad Aziz; Shekhar Srivastava; Saad Alghamdi; Sultan Akhtar; Hussain Almalki; Syed Adil; Mujeeb Khan; Mohammad Hatshan. 2021. "Counteraction of Biofilm Formation and Antimicrobial Potential of Terminalia catappa Functionalized Silver Nanoparticles against Candida albicans and Multidrug-Resistant Gram-Negative and Gram-Positive Bacteria." Antibiotics 10, no. 6: 725.
Graphene nanocomposites have gained significant interest in a variety of biological applications due to their unique properties. Herein, we have studied the apoptosis-inducing ability and anticancer properties of functionalized highly reduced graphene oxide (HRG) and gold nanoparticles (Au NPs)-based nanocomposites (AP-HRG-Au). Samples were prepared under facile conditions via simple stirring and ultrasonication. All the samples were tested for their anticancer properties against different human cancer cell lines including lung (A549), liver (HepG2), and breast (MCF-7) cancer cells using doxorubicin as a positive control. In order to enhance the solubility and bioavailability of the sample, HRG was functionalized with 1-aminopyrene (1-AP) as a stabilizing ligand. The ligand also facilitated the homogeneous growth of Au NPs on the surface of HRG by offering chemically specific binding sites. The synthesis of nanocomposites and the surface functionalization of HRG were confirmed by UV–Vis, powder X-ray diffraction, and Fourier transform infrared spectroscopy. The structure and morphology of the as-prepared nanocomposites were established by high-resolution transmission electron microscopy. Because of the functionalization, the AP-HRG-Au nanocomposite exhibited enhanced physical stability and high dispersibility. A comparative anticancer study of pristine HRG, nonfunctionalized HRG-Au, and 1-AP-functionalized AP-HRG-Au nanocomposites revealed the enhanced apoptosis ability of functionalized nanocomposites compared to the nonfunctionalized sample, whereas the pristine HRG did not show any anticancer ability against all tested cell lines. Both HRG-Au and AP-HRG-Au have induced a concentration-dependent reduction in cell viability in all tested cell lines after 48 h of exposure, with a significantly higher response in MCF-7 cells compared to the remaining cells. Therefore, MCF-7 cells were selected to perform detailed investigations using apoptosis assay, cell cycle analysis, and reactive oxygen species measurements. These results suggest that AP-HRG-Au induces enhanced apoptosis in human breast cancer cells.
Syed Farooq Adil; Mohammed Rafi Shaik; Fahd A. Nasr; Ali S. Alqahtani; Mohammad Z. Ahmed; Wajhul Qamar; Mufsir Kuniyil; Adibah Almutairi; Abdulrahman Alwarthan; Mohammed Rafiq H. Siddiqui; Mohammad Rafe Hatshan; Mujeeb Khan. Enhanced Apoptosis by Functionalized Highly Reduced Graphene Oxide and Gold Nanocomposites in MCF-7 Breast Cancer Cells. ACS Omega 2021, 6, 15147 -15155.
AMA StyleSyed Farooq Adil, Mohammed Rafi Shaik, Fahd A. Nasr, Ali S. Alqahtani, Mohammad Z. Ahmed, Wajhul Qamar, Mufsir Kuniyil, Adibah Almutairi, Abdulrahman Alwarthan, Mohammed Rafiq H. Siddiqui, Mohammad Rafe Hatshan, Mujeeb Khan. Enhanced Apoptosis by Functionalized Highly Reduced Graphene Oxide and Gold Nanocomposites in MCF-7 Breast Cancer Cells. ACS Omega. 2021; 6 (23):15147-15155.
Chicago/Turabian StyleSyed Farooq Adil; Mohammed Rafi Shaik; Fahd A. Nasr; Ali S. Alqahtani; Mohammad Z. Ahmed; Wajhul Qamar; Mufsir Kuniyil; Adibah Almutairi; Abdulrahman Alwarthan; Mohammed Rafiq H. Siddiqui; Mohammad Rafe Hatshan; Mujeeb Khan. 2021. "Enhanced Apoptosis by Functionalized Highly Reduced Graphene Oxide and Gold Nanocomposites in MCF-7 Breast Cancer Cells." ACS Omega 6, no. 23: 15147-15155.
A simple and efficient BF3-OEt2 promoted C3-alkylation of indole has been developed to obtain3-indolylsuccinimidesfrom commercially available indoles and maleimides, with excellent yields under mild reaction conditions. Furthermore, anti-proliferative activity of these conjugates was evaluated against HT-29 (Colorectal), Hepg2 (Liver) and A549 (Lung) human cancer cell lines. One of the compounds, 3w, having N,N-Dimethylatedindolylsuccinimide is a potent congener amongst the series with IC50 value 0.02 µM and 0.8 µM against HT-29 and Hepg2 cell lines, respectively, and compound 3i was most active amongst the series with IC50 value 1.5 µM against A549 cells. Molecular docking study and mechanism of reaction have briefly beendiscussed. This method is better than previous reports in view of yield and substrate scope including electron deficient indoles.
Iqbal Shaikh; Abdul Rahim; Shaikh Faazil; Syed Adil; Mohamed Assal; Mohammad Hatshan. BF3-OEt2 Catalyzed C3-Alkylation of Indole: Synthesis of Indolylsuccinimidesand Their Cytotoxicity Studies. Molecules 2021, 26, 2202 .
AMA StyleIqbal Shaikh, Abdul Rahim, Shaikh Faazil, Syed Adil, Mohamed Assal, Mohammad Hatshan. BF3-OEt2 Catalyzed C3-Alkylation of Indole: Synthesis of Indolylsuccinimidesand Their Cytotoxicity Studies. Molecules. 2021; 26 (8):2202.
Chicago/Turabian StyleIqbal Shaikh; Abdul Rahim; Shaikh Faazil; Syed Adil; Mohamed Assal; Mohammad Hatshan. 2021. "BF3-OEt2 Catalyzed C3-Alkylation of Indole: Synthesis of Indolylsuccinimidesand Their Cytotoxicity Studies." Molecules 26, no. 8: 2202.
The mixed metal oxides Bi2MoO6 and La-doped Bi2MoO6 were prepared by the sol–gel method. Then, varying quantities of the as-prepared mixed metal oxides were blended with graphene oxide (GO), employing sonication, to obtain Bi2MoO6 /GO (BM/GO) and La-Bi2MoO6 /GO (LBM/GO) nanocomposites. These prepared materials were characterized by different techniques such as thermal gravimetric analysis (TGA), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), and transmission electron microscopy (TEM). Dielectric properties were studied by using a precision impedance analyzer. Dielectric constant and loss tan of the synthesized composites were studied as a function of frequency by using a precision impedance analyzer. Overall, the dielectric constant (ɛ’) observed for the LBM/GO composites was higher than that of BM/GO.
Syed Adil; Shoomaila Latif; Muhammad Waqar; Muhammad Imran; Sadia Noreen; Mujeeb Khan; Mohammed Shaik; Mohammad Hatshan. Dielectric Studies of Bi2MoO6/Graphene Oxide and La-Doped Bi2MoO6/Graphene Oxide Nanocomposites. Metals 2021, 11, 559 .
AMA StyleSyed Adil, Shoomaila Latif, Muhammad Waqar, Muhammad Imran, Sadia Noreen, Mujeeb Khan, Mohammed Shaik, Mohammad Hatshan. Dielectric Studies of Bi2MoO6/Graphene Oxide and La-Doped Bi2MoO6/Graphene Oxide Nanocomposites. Metals. 2021; 11 (4):559.
Chicago/Turabian StyleSyed Adil; Shoomaila Latif; Muhammad Waqar; Muhammad Imran; Sadia Noreen; Mujeeb Khan; Mohammed Shaik; Mohammad Hatshan. 2021. "Dielectric Studies of Bi2MoO6/Graphene Oxide and La-Doped Bi2MoO6/Graphene Oxide Nanocomposites." Metals 11, no. 4: 559.
In the present study, a simple and eco-friendly route for the synthesis of copper oxide nanoparticles (CuO NPs) using leaf extract of Phyllanthus emblica as fuel has been demonstrated, as P. emblica is a locally available abundant plant. The formation of the as-prepared CuO NPs was confirmed by using various techniques, such as UV–Vis absorption spectroscopy, cold field scanning electron microscopy (CF–SEM), energy dispersive X-ray analysis (EDX), dynamic light scattering (DLS), and X-ray photoelectron (XPS). The hydrodynamic size of the CuO NPs was found to be 80 nm, while the zeta potential of -28.6 mV was obtained. The elemental composition was confirmed by EDX analysis accompanied with elemental mapping, while the crystalline nature was substantiated by the XRD diffractogram. The as-synthesized CuO NPs were studied for their use as an adsorbent material for the removal of As(V) from water. It was confirmed that the CuO NPs effectively removed As(V) via adsorption, and the adsorption efficiency was found to be best at a higher pH. The maximum adsorption capacity of CuO for As(V) was found to be 1.17 mg/g calculated using the Langmuir equation.
Sadia Saif; Syed Adil; Mujeeb Khan; Mohammad Hatshan; Merajuddin Khan; Farzana Bashir. Adsorption Studies of Arsenic(V) by CuO Nanoparticles Synthesized by Phyllanthus emblica Leaf-Extract-Fueled Solution Combustion Synthesis. Sustainability 2021, 13, 2017 .
AMA StyleSadia Saif, Syed Adil, Mujeeb Khan, Mohammad Hatshan, Merajuddin Khan, Farzana Bashir. Adsorption Studies of Arsenic(V) by CuO Nanoparticles Synthesized by Phyllanthus emblica Leaf-Extract-Fueled Solution Combustion Synthesis. Sustainability. 2021; 13 (4):2017.
Chicago/Turabian StyleSadia Saif; Syed Adil; Mujeeb Khan; Mohammad Hatshan; Merajuddin Khan; Farzana Bashir. 2021. "Adsorption Studies of Arsenic(V) by CuO Nanoparticles Synthesized by Phyllanthus emblica Leaf-Extract-Fueled Solution Combustion Synthesis." Sustainability 13, no. 4: 2017.
Textile manufacturing has been one of the highest polluting industrial sectors. It represents about one-fifth of worldwide industrial water pollution. It uses a huge number of chemicals, numerous of which are carcinogenic. The textile industry releases many harmful chemicals, such as heavy metals and formaldehyde, into water streams and soil, as well as toxic gases such as suspended particulate matter and sulphur dioxide to air. These hazardous wastes, may cause diseases and severe problems to human health such as respiratory and heart diseases. Pollution caused by the worldwide textile manufacturing units results in unimaginable harm, such as textile polymers, auxiliaries and dyes, to the environment. This review presents a systematic and comprehensive survey of all recently produced high-performance textiles; and will therefore assist a deeper understanding of technical textiles providing a bridge between manufacturer and end-user. Moreover, the achievements in advanced applications of textile material will be extensively studied. Many classes of technical textiles were proved in a variety of applications of different fields. The introductory material- and process-correlated identifications regarding raw materials and their transformation into yarns, fibers and fabrics followed by dyeing, printing, finishing of technical textiles and their further processing will be explored. Thus, the environmental impacts of technical textiles on soil, air and water are discussed.
Ali Aldalbahi; Mehrez El-Naggar; Mohamed El-Newehy; Mostafizur Rahaman; Mohammad Hatshan; Tawfik Khattab. Effects of Technical Textiles and Synthetic Nanofibers on Environmental Pollution. Polymers 2021, 13, 155 .
AMA StyleAli Aldalbahi, Mehrez El-Naggar, Mohamed El-Newehy, Mostafizur Rahaman, Mohammad Hatshan, Tawfik Khattab. Effects of Technical Textiles and Synthetic Nanofibers on Environmental Pollution. Polymers. 2021; 13 (1):155.
Chicago/Turabian StyleAli Aldalbahi; Mehrez El-Naggar; Mohamed El-Newehy; Mostafizur Rahaman; Mohammad Hatshan; Tawfik Khattab. 2021. "Effects of Technical Textiles and Synthetic Nanofibers on Environmental Pollution." Polymers 13, no. 1: 155.
Thermochromic urea (U) organogel immobilized with a thermochromic tricyanofuran hydrazone (TCFH) chromophore was developed. Thermochromic TCFH chromophore bearing two nitro functional groups on a hydrazone recognition unit was synthesized via an azo-coupling reaction of tricyanofuran (TCF) heterocyclic moiety containing an active methyl group with the diazonium chloride salt of 2,4-dinitroaniline comprising two strongly electron-withdrawing nitro groups. The molecular structure of both intermediates and TCFH dye were characterized by several analytical methods, including 1H NMR, 13C NMR, IR, mass spectroscopy (MS), and elemental analysis. The thermochromic responsiveness could be attributed to the charge delocalization of TCFH as well as to the presence of an intramolecular charge transfer. The generated organogel displayed a thermoreversible sol–gel transition associated with color change. The origin of the monitored thermochromism is a conformational change of the tricyanofuran hydrazone backbone due to the temperature-driven deprotonation–protonation reversible process. The prepared urea–tricyanofuran hydrazone (UTCFH) thermometer acted as a diagnostic tool providing an instant color change between yellow, orange, red and purple upon changing the temperature of the UTCFH organogel in dimethyl sulfoxide (DMSO). This color change was proportionally correlated with increasing the temperature from 44 to 63 °C. The UTCFH organogel composed of urea and push-π-pull hydrazone type tricyanofuran chromophore immobilized physically in the urea organogel was found to function as a temperature-driven chromic thermometer. This chromogenic UTCFH organogel in DMSO displayed a phase transition at 41–48 °C. The morphological properties of the gel internal fibrous nanostructure (80–120 nm) were monitored by scanning electron microscopy (SEM). The colorimetric measurements were monitored by UV–Vis absorption spectroscopy. The chromogenic thermometer demonstrated a good reversibility without fatigue. The mechanism accounting for thermochromism of UTCFH organogel is proposed.
Tawfik A. Khattab; Mehrez E. El-Naggar; Meram S. Abdelrahman; Ali Aldalbahi; Mohammad Rafe Hatshan. Simple Development of Novel Reversible Colorimetric Thermometer Using Urea Organogel Embedded with Thermochromic Hydrazone Chromophore. Chemosensors 2020, 8, 132 .
AMA StyleTawfik A. Khattab, Mehrez E. El-Naggar, Meram S. Abdelrahman, Ali Aldalbahi, Mohammad Rafe Hatshan. Simple Development of Novel Reversible Colorimetric Thermometer Using Urea Organogel Embedded with Thermochromic Hydrazone Chromophore. Chemosensors. 2020; 8 (4):132.
Chicago/Turabian StyleTawfik A. Khattab; Mehrez E. El-Naggar; Meram S. Abdelrahman; Ali Aldalbahi; Mohammad Rafe Hatshan. 2020. "Simple Development of Novel Reversible Colorimetric Thermometer Using Urea Organogel Embedded with Thermochromic Hydrazone Chromophore." Chemosensors 8, no. 4: 132.
Bee pollens are rich source of essential amino acids and are often considered as complete food for human beings. Herein, we exploited the potential reducing abilities of Bee pollens extract for the eco-friendly preparation of silver nanoparticles (AgNPs-G). The resulting NPs were characterized using a combination of microscopic and spectroscopic techniques. The analyses confirm the formation of spherical Ag NPs. AgNPs-G obtained from the aqueous extract of bee pollens was used to study their antibacterial properties against Gram-positive and Gram-negative microbes using the Minimum Inhibitory Concentration 50 (MIC50) method. The antibacterial properties of AgNPs-G were compared to the properties of chemically synthesized Ag NPs (AgNPs-C) using sodium borohydride as a reducing agent. The green synthesized nanoparticles (AgNPs-G) exhibited a better antibacterial activity against most of the studied strains when compared to the chemically synthesized Ag NPs (AgNPs-C). In addition, the anti-cancer activity of Ag NPs was also studied against human liver and breast carcinoma cell lines by applying MTT-assay. The Ag NPs demonstrated considerable anticancer activity against the studied cell lines and exhibited high IC50 values in both MCF-7 and HepG2 cell lines.
Hanan M. Al-Yousef; Musarat Amina; Ali S. Alqahtani; Mohammed S. Alqahtani; Abdul Malik; Mohammad Rafe Hatshan; Mohammed Rafiq H. Siddiqui; Mujeeb Khan; Mohammed Rafi Shaik; Mohammad Shamsul Ola; Rabbani Syed. Pollen Bee Aqueous Extract-Based Synthesis of Silver Nanoparticles and Evaluation of Their Anti-Cancer and Anti-Bacterial Activities. Processes 2020, 8, 524 .
AMA StyleHanan M. Al-Yousef, Musarat Amina, Ali S. Alqahtani, Mohammed S. Alqahtani, Abdul Malik, Mohammad Rafe Hatshan, Mohammed Rafiq H. Siddiqui, Mujeeb Khan, Mohammed Rafi Shaik, Mohammad Shamsul Ola, Rabbani Syed. Pollen Bee Aqueous Extract-Based Synthesis of Silver Nanoparticles and Evaluation of Their Anti-Cancer and Anti-Bacterial Activities. Processes. 2020; 8 (5):524.
Chicago/Turabian StyleHanan M. Al-Yousef; Musarat Amina; Ali S. Alqahtani; Mohammed S. Alqahtani; Abdul Malik; Mohammad Rafe Hatshan; Mohammed Rafiq H. Siddiqui; Mujeeb Khan; Mohammed Rafi Shaik; Mohammad Shamsul Ola; Rabbani Syed. 2020. "Pollen Bee Aqueous Extract-Based Synthesis of Silver Nanoparticles and Evaluation of Their Anti-Cancer and Anti-Bacterial Activities." Processes 8, no. 5: 524.
Metal Enhanced Fluorescence (MEF) has promising applications in the field of optical displays, bio-sensing and photodynamic therapy. In this work, we exploit the plasmons of embedded silver nanoparticles (Ag NPs) fabricated by ion implantation to enhance the fluorescence of Coumarin515 dye (C515) via MEF. Ion Implantation of 70 keV Ag ions in quartz matrix at different fluences was carried out to synthesize Ag nanoparticles inside quartz matrix. The formation of Ag NPs is characterized by the optical absorption measurements and approximate sizes of Ag NPs was obtained from the fitting of the optical absorption spectra with Mie theory calculations. Rutherford Backscattering Spectrometry (RBS) measurement was used to obtain the depth profile and concentration Ag within the substrate. From the RBS results, it was determined that front edge of the layer containing Ag was formed at an average depth of 16 nm below the surface, which closely agreed with Stopping and Range of Ions in Matter (SRIM) calculations. Increase in the size of the NPs is observed as the fluence of the Ag within the substrate is increased. The MEF of drop casted C515 dye was studied using steady-state emission and excitation spectra measurements. Fluorescence enhancement factor ranging from 1.0 to 2.1 with a maximum enhancement for the largest size NP was obtained. The observed MEF was ascribed to a combination of plasmon enhancement with larger nanoparticles and to increased plasmonic hot spots.
Shahid Iqbal; Masoud Shabaninezhad; Mohammad Rafe Hatshan; Prashanta M. Niraula; Abubaker Abuhagr; Hasna Alali; Ramakrishna Guda; Asghar Kayani. Ion-implanted silver nanoparticles for metal-enhanced fluorescence. AIP Advances 2018, 8, 095217 .
AMA StyleShahid Iqbal, Masoud Shabaninezhad, Mohammad Rafe Hatshan, Prashanta M. Niraula, Abubaker Abuhagr, Hasna Alali, Ramakrishna Guda, Asghar Kayani. Ion-implanted silver nanoparticles for metal-enhanced fluorescence. AIP Advances. 2018; 8 (9):095217.
Chicago/Turabian StyleShahid Iqbal; Masoud Shabaninezhad; Mohammad Rafe Hatshan; Prashanta M. Niraula; Abubaker Abuhagr; Hasna Alali; Ramakrishna Guda; Asghar Kayani. 2018. "Ion-implanted silver nanoparticles for metal-enhanced fluorescence." AIP Advances 8, no. 9: 095217.
Accurate measurements of intracellular pH are of crucial importance in understanding the cellular activities and in the development of intracellular drug delivery systems. Here we report a highly sensitive pH probe based on a fluorescein-conjugated Au22 nanocluster. Steady-state photoluminescence (PL) measurements have shown that, when conjugated to Au22, fluorescein exhibits more than 160-fold pH-contrasting PL in the pH range of 4.3–7.8. Transient absorption measurements show that there are two competing ultrafast processes in the fluorescein-conjugated Au22 nanocluster: the intracore-state relaxation and the energy transfer from the nonthermalized states of Au22 to fluorescein. The latter becomes predominant at a higher pH, leading to dramatic PL enhancement of fluorescein. In addition to the intrinsically low toxicity, fluorescein-conjugated Au22 nanoclusters exhibit high pH sensitivity, wide dynamic range, and excellent photostability, providing a powerful tool for the study of intracellular processes.
Kyunglim Pyo; Nguyen Hoang Ly; Sang Myeong Han; Mohammad bin Hatshan; Abubkr Abuhagr; Gary Wiederrecht; Sang-Woo Joo; Guda Ramakrishna; Dongil Lee. Unique Energy Transfer in Fluorescein-Conjugated Au22 Nanoclusters Leading to 160-Fold pH-Contrasting Photoluminescence. The Journal of Physical Chemistry Letters 2018, 9, 5303 -5310.
AMA StyleKyunglim Pyo, Nguyen Hoang Ly, Sang Myeong Han, Mohammad bin Hatshan, Abubkr Abuhagr, Gary Wiederrecht, Sang-Woo Joo, Guda Ramakrishna, Dongil Lee. Unique Energy Transfer in Fluorescein-Conjugated Au22 Nanoclusters Leading to 160-Fold pH-Contrasting Photoluminescence. The Journal of Physical Chemistry Letters. 2018; 9 (18):5303-5310.
Chicago/Turabian StyleKyunglim Pyo; Nguyen Hoang Ly; Sang Myeong Han; Mohammad bin Hatshan; Abubkr Abuhagr; Gary Wiederrecht; Sang-Woo Joo; Guda Ramakrishna; Dongil Lee. 2018. "Unique Energy Transfer in Fluorescein-Conjugated Au22 Nanoclusters Leading to 160-Fold pH-Contrasting Photoluminescence." The Journal of Physical Chemistry Letters 9, no. 18: 5303-5310.
Here we report the synthesis and size-dependent optical study of a series of bulky t-butyl thiolated monodisperse nanomolecules (NMs): Au23(S-tBu)16, Au30(S-tBu)18, Au46(S-tBu)24, and Au65(S-tBu)29. We further employ this series of NMs to address how the NM core size affects electrocatalytic oxygen reduction reactivity of these NMs in alkaline media. Though Au23(S-tBu)16 and Au30(S-tBu)18 have been reported before, the expansion of this series is brought about by the discovery, through the synthesis and characterization, of two new and larger species, in the bulky t-butyl thiolated NM series: namely Au46(S-tBu)24 and Au65(S-tBu)29. Furthermore, we take an in-depth look at the ligand effects in the bulky thiolated NM series and ligand dictation over the gold atoms to surface ligands. Assignments of molecular formulae are based on results obtained in high-resolution nanoelectrospray ionization mass spectrometry (nESI-MS). Purity was confirmed with matrix assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Further analysis of the new bulky thiolated NMs, Au46(S-tBu)24 and Au65(S-tBu)29, was conducted using UV–vis-NIR spectroscopy to observe their unique optical properties. With the expansion of this series, we conclude that the bulky t-butyl thiolated series is unique from those observed with aliphatic and aromatic ligands; that is, how the bulky ligands dictate the size, composition, and structure of the NM is distinct from those of aliphatic and aromatic ligands. This provides insight into the tunability and core size manipulation of gold thiolate NM (i.e., we can make different sizes of NMs using specific types of ligands by varying the gold to thiol ratio). The largest NM Au65(S-tBu)29 was found to facilitate 80% OH– production, while the smallest size NM Au23(S-tBu)16 produced 53% OH–. From the optical measurements we determined that the excited state lifetimes of this series of t-butyl thiolate protected gold NMs follow the energy gap law except for Au30(S-tBu)18 which can be ascribed to its symmetry.
Tanya C. Jones; Leigh Sumner; Guda Ramakrishna; Mohammad Rafe Hatshan; Abubkr Abuhagr; Saumen Chakraborty; Amala Dass. Bulky t-Butyl Thiolated Gold Nanomolecular Series: Synthesis, Characterization, Optical Properties, and Electrocatalysis. The Journal of Physical Chemistry C 2018, 122, 17726 -17737.
AMA StyleTanya C. Jones, Leigh Sumner, Guda Ramakrishna, Mohammad Rafe Hatshan, Abubkr Abuhagr, Saumen Chakraborty, Amala Dass. Bulky t-Butyl Thiolated Gold Nanomolecular Series: Synthesis, Characterization, Optical Properties, and Electrocatalysis. The Journal of Physical Chemistry C. 2018; 122 (31):17726-17737.
Chicago/Turabian StyleTanya C. Jones; Leigh Sumner; Guda Ramakrishna; Mohammad Rafe Hatshan; Abubkr Abuhagr; Saumen Chakraborty; Amala Dass. 2018. "Bulky t-Butyl Thiolated Gold Nanomolecular Series: Synthesis, Characterization, Optical Properties, and Electrocatalysis." The Journal of Physical Chemistry C 122, no. 31: 17726-17737.