Carboxylic acids and light interact to affect nanoceria stability and dissolution in acidic aqueous environments

• Matthew L. Hancock,
• Eric A. Grulke and
• Robert A. Yokel

Beilstein J. Nanotechnol. 2023, 14, 762–780, doi:10.3762/bjnano.14.63

• during its synthesis; in fact, a carboxylic acid, namely citric acid, is used in many synthesis protocols. Citric acid adsorbs onto nanoceria surfaces, limiting particle formation and creating stable dispersions with extended shelf life. To better understand factors influencing the fate of nanoceria, its

• ]. Nanoceria (33 and 78 nm) dissolved at pH values less than 5 and to a greater extent at pH 1.65. The dissolution rate was proportional to the surface area [32]. Nanoceria dissolution was observed at pH 5.5 in the presence of citric acid and other reducing agents after 21 days [18]. Carboxylic acids

• ]. When exposed to artificial sunlight, ceria nanoparticles produced hydroxy radicals and induced lipid peroxidation of the gills of cardinal tetra, a native species of the Rio Negro region [45]. The citric acid coating can also be altered by UV irradiation. Photolysis of citric acid under a Hg lamp

Bismuth-based nanostructured photocatalysts for the remediation of antibiotics and organic dyes

• Akeem Adeyemi Oladipo and
• Faisal Suleiman Mustafa

Beilstein J. Nanotechnol. 2023, 14, 291–321, doi:10.3762/bjnano.14.26

Structural studies and selected physical investigations of LiCoO₂ obtained by combustion synthesis

• Monika Michalska,
• Paweł Ławniczak,
• Tomasz Strachowski,
• Adam Ostrowski and
• Waldemar Bednarski

Beilstein J. Nanotechnol. 2022, 13, 1473–1482, doi:10.3762/bjnano.13.121

• carboxylates were investigated as fuels, including ammonium acetate, ammonium citrate, or ammonium tartarate [55], urea [56], starch [57], citric acid [58], and 1,2-diformylhydrazine [59]. The obtained LCO precursors were annealed in air between 300 and 850 °C [55][56][57][58][59]. Herein, we demonstrate a new

Recent advances in green carbon dots (2015–2022): synthesis, metal ion sensing, and biological applications

• Aisha Kanwal,
• Naheed Bibi,
• Sajjad Hyder,
• Arif Muhammad,
• Hao Ren,
• Jiangtao Liu and
• Zhongli Lei

Beilstein J. Nanotechnol. 2022, 13, 1068–1107, doi:10.3762/bjnano.13.93

• glycol [6], phytic acid [7], phenylenediamine [8], ammonium citrate [9], citric acid [10], ethylene diamine tetra acetic acid [11], carbon nanotubes [12], and graphite [13]. Additionally, graphite, nanodiamonds, and activated carbon can be applied as precursor for the fabrication of CDs [14]. Meanwhile

• produce highly luminous CDs via a simple, low-cost hydrothermal route. This novel study explained how hydrothermal time and source type affects the luminescence of CDs [60]. To study the effect of citric acid on the precursors, different precursors (such as ripe lemon juice, fresh lemon juice, and orange

• juice) were tested. It was found that the photoluminescence (PL) intensity of citric acid was higher than that of lemon juice, which, in turn, was higher than that of orange juice. This outcome is the result of lemon juice having a greater citric acid concentration than orange juice. Compared to ripe

Solar-light-driven LaFe_xNi_1−xO₃ perovskite oxides for photocatalytic Fenton-like reaction to degrade organic pollutants

• Chao-Wei Huang,
• Shu-Yu Hsu,
• Jun-Han Lin,
• Yun Jhou,
• Wei-Yu Chen,
• Kun-Yi Andrew Lin,
• Yu-Tang Lin and
• Van-Huy Nguyen

Beilstein J. Nanotechnol. 2022, 13, 882–895, doi:10.3762/bjnano.13.79

• were lanthanum nitrate hexahydrate (99.9%, La(NO3)3·6H2O, Alfa Aesar), ferric nitrate nonahydrate (≥98.0%, Fe(NO3)3·9H2O, J.T. Baker), and nickel nitrate hexahydrate (98.0%, Ni(NO3)2·6H2O, Showa), respectively. The citric acid (95.0%, C6H8O7) and ammonia (28.0–30.0%, NH4OH) were both obtained from J.T

• (≥98.0%, TC, C22H24N2O8), were provided from Sigma-Aldrich. Commercial tungsten oxide (99.8%, WO3) was bought from Alfa Aesar. Synthesis of LaFexNi1−xO3 The LaFexNi1−xO3 catalysts were synthesized via the sol–gel method with citric acid crosslinking reaction, followed by self-propagating high-temperature

• 0.1/0.9, 0.3/0.7, 0.5/0.5, 0.7/0.3, and 0.9/0.1. Accordingly, the chemical stoichiometric ratios of Fe and Ni were noted as x and 1−x, respectively. Second, 0.1 mol citric acid (C6H8O7) was also dissolved into the mixed solution as the cross-linking agent to gradually form the gel solution with light

Morphology-driven gas sensing by fabricated fractals: A review

• Vishal Kamathe and
• Rupali Nagar

Beilstein J. Nanotechnol. 2021, 12, 1187–1208, doi:10.3762/bjnano.12.88

• ethanol and citric acid played a vital role in the growth of the dendrite nanostructure, which exhibited a fractal dimension of 1.94. Bismuth vanadate -based fractals Zhao et al. synthesized large-scale highly uniform hyperbranched monoclinic BiVO4 (h-BiVO4) structures by a surfactant-free hydrothermal

The role of deep eutectic solvents and carrageenan in synthesizing biocompatible anisotropic metal nanoparticles

• Nabojit Das,
• Akash Kumar and
• Raja Gopal Rayavarapu

Beilstein J. Nanotechnol. 2021, 12, 924–938, doi:10.3762/bjnano.12.69

• was observed due to the difference in the binding affinity of the capping agents toward serum proteins. Glutathione showed less affinity towards serum proteins than citric acid. In an exposure time duration study by Lopez-Chaves et al., size-dependent metabolic fate and deposit formation of gold

• for dissolving many species of high polarity, for example, amino acids, metal salts, glycerol, benzoic acid, citric acid, and glucose [26][76]. They are also promising in the dissolution of different polymers, such as starch, cellulose, lignin, chitin, and are also used in the pre-treatment of

Impact of GaAs(100) surface preparation on EQE of AZO/Al₂O₃/p-GaAs photovoltaic structures

• Piotr Caban,
• Rafał Pietruszka,
• Jarosław Kaszewski,
• Monika Ożga,
• Bartłomiej S. Witkowski,
• Krzysztof Kopalko,
• Piotr Kuźmiuk,
• Katarzyna Gwóźdź,
• Ewa Płaczek-Popko,
• Krystyna Lawniczak-Jablonska and
• Marek Godlewski

Beilstein J. Nanotechnol. 2021, 12, 578–592, doi:10.3762/bjnano.12.48

• ) properties and bandgap measurements of the deposited layers were also reported. The highest EQE value was obtained for the samples initially etched with a citric acid-based etchant and, in the last preparation step, either passivated with ammonium sulfide aqueous solution or treated with ammonium hydroxide

• aqueous solutions are used with the addition of an oxidizer – usually hydrogen peroxide (H2O2). Such an etchant is able to turn GaAs into oxide and dissolve the created oxides “at the same time”. The popular etchants are H2SO4/H2O2/H2O, NH4OH/H2O2/H2O, and citric acid (CA)-based etchants – CA/H2O2/H2O [17

• ). For the etching of native oxide and suboxide gallium arsenide layers, 50 g of citric acid monohydrate (CA) C6H8O7·H2O (CAS: 5949-29-1) was dissolved into 50 mL of DIW. Since this is an endothermic reaction, the solution temperature initially dropped to approx. 8 °C. Further stirring for several

The preparation temperature influences the physicochemical nature and activity of nanoceria

• Robert A. Yokel,
• Wendel Wohlleben,
• Johannes Georg Keller,
• Matthew L. Hancock,
• Jason M. Unrine,
• D. Allan Butterfield and
• Eric A. Grulke

Beilstein J. Nanotechnol. 2021, 12, 525–540, doi:10.3762/bjnano.12.43

• Research Centre Institute for Health and Consumer Protection repository of reference materials from the OECD sponsorship program. The solvothermally synthesized nanoceria material was prepared using a hydrothermal method [34]. Briefly, 0.25 M cerium chloride heptahydrate and 0.25 M citric acid monohydrate

• were added to 1.5 M ammonium hydroxide, stirred, and autoclaved for 24 h at 50 °C then 24 h at 80 °C. The product was dialyzed against 110 mM pH 7.4 citric acid for 120 h, replacing the dialysate every 24 h, then dialyzed against DI water to remove citric acid and ionic cerium for an additional 72 h

• immersed in 200 mL of pH 4.5 iso-osmotic citric acid, and agitated as described above in section “Nanoceria dissolution”. Samples withdrawn from a cassette after 75, 102, and 152 days were dialyzed against water, as described above in the synthesis of the solvothermally synthesized nanoceria. The

Solution combustion synthesis of a nanometer-scale Co₃O₄ anode material for Li-ion batteries

• Monika Michalska,
• Huajun Xu,
• Qingmin Shan,
• Shiqiang Zhang,
• Yohan Dall'Agnese,
• Yu Gao,
• Amrita Jain and
• Marcin Krajewski

Beilstein J. Nanotechnol. 2021, 12, 424–431, doi:10.3762/bjnano.12.34

• the previously used urea [48][49][51] and citric acid [50][52]. ᴅ-(+)-glucose has been used as alternative fuel for the SCS process mainly for two reasons. The first one is that ᴅ-(+)-glucose is a naturally abundant form of glucose, which is formed during photosynthesis by plants and most algae [53

A review on the biological effects of nanomaterials on silkworm (Bombyx mori)

• Sandra Senyo Fometu,
• Guohua Wu,
• Lin Ma and
• Joan Shine Davids

Beilstein J. Nanotechnol. 2021, 12, 190–202, doi:10.3762/bjnano.12.15

• in order to deal with foreign cells. Quantum dots have unique optical properties that are used in biological imaging [147][148][149][150]. They are also known for their size-dependent cytotoxicity [151][152]. Silkworms were subjected to doses of 32 mM of CdTe QDs, 1 µg/µL of citric acid–nitrogen

Photothermally active nanoparticles as a promising tool for eliminating bacteria and biofilms

• Mykola Borzenkov,
• Piersandro Pallavicini,
• Angelo Taglietti,
• Laura D’Alfonso,
• Maddalena Collini and
• Giuseppe Chirico

Beilstein J. Nanotechnol. 2020, 11, 1134–1146, doi:10.3762/bjnano.11.98

• after one round of laser exposure. Poly(vinyl alcohol) (PVA) films cross-linked with citric acid loaded with highly efficient photothermal gold nanostars were also fabricated [66]. The resulting films demonstrated a pronounced photothermal effect under NIR irradiation in the 730–1064 nm wavelength range

Applications of superparamagnetic iron oxide nanoparticles in drug and therapeutic delivery, and biotechnological advancements

• Maria Suciu,
• Corina M. Ionescu,
• Alexandra Ciorita,
• Septimiu C. Tripon,
• Dragos Nica,
• Hani Al-Salami and
• Lucian Barbu-Tudoran

Beilstein J. Nanotechnol. 2020, 11, 1092–1109, doi:10.3762/bjnano.11.94

• stability in cell culture media, it was demonstrated that poly(methacrylic acid)-coated SPIONs and citric acid-coated SPIONs are stable in common cell culture media (DMEM, RPMI), when serum was added, but produced aggregates larger than 1 µm in simple media and in phosphate buffer [54]. Stability and

Soybean-derived blue photoluminescent carbon dots

• Shanshan Wang,
• Wei Sun,
• Dong-sheng Yang and
• Fuqian Yang

Beilstein J. Nanotechnol. 2020, 11, 606–619, doi:10.3762/bjnano.11.48

• luminescence properties. Hydrothermal carbonization (HTC), which can be considered as a “green technology”, has been used to produce photoluminescent CDs from biomass, including glucose, sucrose, citric acid [19], chitosan [20], orange juice [21], grass [22] and soy milk [10]. For example, Sahu et al. [21

Fully amino acid-based hydrogel as potential scaffold for cell culturing and drug delivery

• Dávid Juriga,
• Evelin Sipos,
• Orsolya Hegedűs,
• Gábor Varga,
• Miklós Zrínyi,
• Krisztina S. Nagy and
• Angéla Jedlovszky-Hajdú

Beilstein J. Nanotechnol. 2019, 10, 2579–2593, doi:10.3762/bjnano.10.249

• dihydrochloride (CAS: 56-17-7, Fluka, ≥98%), lysine methyl ester dihydrochloride (CAS: 26348-70-9, Bachem, 97%), dimethyl sulfoxide (CAS: 67-68-5, VWR, ≥99%), dibutylamine (CAS: 111-92-2, Aldrich, ≥99.5%), citric acid monohydrate (CAS: 5949-29-1, VWR, 100%, normapur), imidazole (CAS.288-32-4, Sigma-Aldrich, ≥99.5

Review of advanced sensor devices employing nanoarchitectonics concepts

• Katsuhiko Ariga,
• Tatsuyuki Makita,
• Masato Ito,
• Taizo Mori,
• Shun Watanabe and
• Jun Takeya

Beilstein J. Nanotechnol. 2019, 10, 2014–2030, doi:10.3762/bjnano.10.198

• an organic field-effect transistor, which was used for the sensitive detection of small organic acid molecules, such as citric acid [142]. Hattori and co-workers fabricated an ATP/ADP sensitive image sensor by immobilization of apyrase as a self-assembled monolayer on a 128 × 128 pixel array

Optimization and performance of nitrogen-doped carbon dots as a color conversion layer for white-LED applications

• Tugrul Guner,
• Hurriyet Yuce,
• Didem Tascioglu,
• Eren Simsek,
• Umut Savaci,
• Aziz Genc,
• Servet Turan and
• Mustafa M. Demir

Beilstein J. Nanotechnol. 2019, 10, 2004–2013, doi:10.3762/bjnano.10.197

• another work, novel nitrogen-doped multiple-core@shell-structured AC-CDots (AC: Aphen and Citric acid) with a tricolor emission comprising red, green, and blue were, for the first time, synthesized via a one-pot hydrothermal approach by Zhang et al. [49]. The authors further demonstrated that by combining

Co-doped MnFe₂O₄ nanoparticles: magnetic anisotropy and interparticle interactions

• Bagher Aslibeiki,
• Parviz Kameli,
• Hadi Salamati,
• Giorgio Concas,
• Maria Salvador Fernandez,
• Alessandro Talone,
• Giuseppe Muscas and
• Davide Peddis

Beilstein J. Nanotechnol. 2019, 10, 856–865, doi:10.3762/bjnano.10.86

• (x = 0, 0.25, 0.5, 0.75, 1) were synthesized following a simple method based on solid-state ball milling and calcination of nitrate precursors and citric acid, discussed previously to prepare pure MnFe2O4 [22]. Manganese nitrate (Mn(NO3)2·4H2O, Merck, 99%), iron nitrate (Fe(NO3)3·9H2O, Merck, 99

• %), cobalt nitrate (Co(NO3)2·6H2O, Merck, 98.5%) and citric acid (C6H6O7, Merck, 99.5%) powders were mixed in a 1:1 molar ratio of total metal nitrates to citric acid. The powders were milled for 1 h in a planetary ball mill using agate balls, producing an amorphous precursor (Supporting Information File 1

Cytotoxicity of doxorubicin-conjugated poly[N-(2-hydroxypropyl)methacrylamide]-modified γ-Fe₂O₃ nanoparticles towards human tumor cells

• Zdeněk Plichta,
• Yulia Kozak,
• Rostyslav Panchuk,
• Viktoria Sokolova,
• Matthias Epple,
• Lesya Kobylinska,
• Pavla Jendelová and
• Daniel Horák

Beilstein J. Nanotechnol. 2018, 9, 2533–2545, doi:10.3762/bjnano.9.236

• chemical attachment of target biomolecules, reduces cytotoxicity, and controls particle uptake by the cells [10]. Coatings can be either of low molecular weight, such are carbohydrates and organic acids (ethylenediaminetetraacetic acid, tartaric acid, citric acid, succinic acid, bisphosphonic acid), or of

Fabrication of photothermally active poly(vinyl alcohol) films with gold nanostars for antibacterial applications

• Mykola Borzenkov,
• Maria Moros,
• Claudia Tortiglione,
• Serena Bertoldi,
• Nicola Contessi,
• Silvia Faré,
• Angelo Taglietti,
• Agnese D’Agostino,
• Piersandro Pallavicini,
• Maddalena Collini and
• Giuseppe Chirico

Beilstein J. Nanotechnol. 2018, 9, 2040–2048, doi:10.3762/bjnano.9.193

• properties of the films [20]. Citric acid was chosen as the crosslinking agent as, in comparison with the widely used method of crosslinking with glutaraldehyde, it is a non-toxic compound approved as a food additive, thus providing a green crosslinking route [20][25]. GNSs were synthesized via a seed-growth

• lead to new, easily prepared, NIR-activated, reusable, antibacterial materials suitable for surface coating. Experimental Materials PVA with an average molecular weight of 72000 g/mol (degree of hydrolysis 98%) was purchased from Sigma-Aldrich. Anhydrous citric acid and poly(ethylene glycol) (PEG-200

• stirred at ≈40 °C. 1.45 mL of PEGylated GNS solution were added dropwise and the mixture was stirred 5 h at ≈40 °C. Then, citric acid (0.1 g) was added and 5 mL of the resulting solution were cast into a Petri dish. Once the film was formed, it was sintered 20 min at 130 °C to complete crosslinking. The

Nanocomposites comprised of homogeneously dispersed magnetic iron-oxide nanoparticles and poly(methyl methacrylate)

• Sašo Gyergyek,
• David Pahovnik,
• Ema Žagar,
• Alenka Mertelj,
• Rok Kostanjšek,
• Miloš Beković,
• Marko Jagodič,
• Heinrich Hofmann and
• Darko Makovec

Beilstein J. Nanotechnol. 2018, 9, 1613–1622, doi:10.3762/bjnano.9.153

• dissolution of the Fe cations from the nanocomposite and the nanoparticles was tested with dissolution in the presence of citric acid at pH 1, where further details can be found in Supporting Information File 1. Characterization The particle size, crystallinity and dispersion over the nanocomposites were

• , NP-RA-PMMA and NC-3 in a solution of citric acid. Under sufficiently acidic conditions (pH < 6) the citric acid boosts the dissolution of iron oxide due to the chelate effect [32]. The results are presented as the wt % of dissolved Fe relative to the total Fe in the iron oxide nanoparticles. It was

A review of carbon-based and non-carbon-based catalyst supports for the selective catalytic reduction of nitric oxide

• Shahreen Binti Izwan Anthonysamy,
• Syahidah Binti Afandi,
• Mehrnoush Khavarian and
• Abdul Rahman Bin Mohamed

Beilstein J. Nanotechnol. 2018, 9, 740–761, doi:10.3762/bjnano.9.68

• ” reaction to improve low-temperature SCR activity. The sol–gel method has been used quite frequently for the development of nano-based catalysts. Basically, certain chemical solutions together with a foaming agent (citric acid) is mixed vigorously by stirring under room temperature to produce a homogeneous

• interaction and oxide–oxide interactions that are unreachable otherwise [38]. Xiong et al. [39] prepared magnetic iron–cerium–tungsten mixed oxide pellets using a citric acid sol–gel process assisted by microwave irradiation for the SCR-NH3 of NO. They found that the dispersion of both cerium oxide and

Tuning adhesion forces between functionalized gold colloidal nanoparticles and silicon AFM tips: role of ligands and capillary forces

• Sven Oras,
• Sergei Vlassov,
• Marta Berholts,
• Rünno Lõhmus and
• Karine Mougin

Beilstein J. Nanotechnol. 2018, 9, 660–670, doi:10.3762/bjnano.9.61

• [51] has been applied. The as-synthesized NPs solution [46][47] was centrifuged at 7,000 rpm for 20 min to pellet the NPs, decanted, and then re-suspended in a proper solvent to reduce the citric acid concentration. The supernatant containing the sodium citrate molecules is then removed and 10 mL of

Anchoring Fe₃O₄ nanoparticles in a reduced graphene oxide aerogel matrix via polydopamine coating

• Błażej Scheibe,
• Radosław Mrówczyński,
• Natalia Michalak,
• Karol Załęski,
• Michał Matczak,
• Mateusz Kempiński,
• Zuzanna Pietralik,
• Mikołaj Lewandowski,
• Stefan Jurga and
• Feliks Stobiecki

Beilstein J. Nanotechnol. 2018, 9, 591–601, doi:10.3762/bjnano.9.55

• ), respectively, which may originate from the presence of citric acid or polydopamine. The residual ether-type functional groups can be observed via C–O vibrational band at 1115 cm−1 (IX). The strong band at 1572 cm−1 (VI) could be attributed to a carboxylate C–O–Fe bond, which confirms covalent bonding between

• functional additives at the rGO defect sites, prevent unintended additives migration outside the aerogel and provide better structural stabilization of the whole aerogel structure. Experimental Graphite powder, iron(III) chloride hexahydrate, iron(II) chloride tetrahydrate, sodium nitride 99%, citric acid

• ) was added under vigorous stirring. After 30 minutes, 8 mL of citric acid were added. The process was continued at 95 °C for 90 minutes. Subsequently, the mixture was cooled down to room temperature (RT) and the obtained nanoparticles were washed with DI-H2O (3 × 200 mL) and finally dispersed in 100 mL

Green synthesis of fluorescent carbon dots from spices for in vitro imaging and tumour cell growth inhibition

• Nagamalai Vasimalai,
• Vânia Vilas-Boas,
• Juan Gallo,
• María de Fátima Cerqueira,
• Mario Menéndez-Miranda,
• José Manuel Costa-Fernández,
• Lorena Diéguez,
• Begoña Espiña and
• María Teresa Fernández-Argüelles

Beilstein J. Nanotechnol. 2018, 9, 530–544, doi:10.3762/bjnano.9.51

• -dots in the cancer cultures compared to the non-cancerous cells. Results showed that the spice-derived C-dots inhibited cell viability dose-dependently after a 24 h incubation period, displaying a higher toxicity in LN-229, than in HK-2 cells. As a control, C-dots synthesized from citric acid did not

• , TEM and ESI-QTOF-MS. Moreover, their bioimaging potential and toxicity have been evaluated in vitro in human glioblastoma LN-229 cells and in immortalized epithelial human kidney cells (HK-2). The effects on cancer and non-cancer cells have been also compared with C-dots synthesized from citric acid

• . Most common sources for the synthesis of carbon dots are graphite and citric acid. Graphite is used in top-down synthesis strategies, and uses dimethylformamide (DMF) as surface passivating agent [8]. However, since DMF is harmful to living cells, in this work carbon dots synthesized from graphite were