Potential of a deep eutectic solvent in silver nanoparticle fabrication for antibiotic residue detection

• Le Hong Tho,
• Bui Xuan Khuyen,
• Ngoc Xuan Dat Mai and
• Nhu Hoa Thi Tran

Beilstein J. Nanotechnol. 2024, 15, 426–434, doi:10.3762/bjnano.15.38

• NFT and SDZ, respectively. Besides, the linearity coefficients are extremely close to 1 in the range of 10−8 to 10−3 M of concentration, and the SERS substrate shows remarkable uniformity along with great selectivity. This powerful SERS performance indicates that DESs have tremendous potential in the

• thin film (Figure 3B). The uniform distribution of silver shows the uniformity of Ag NPs-DES thin film on the glass substrate, which is crucial for the applicability of this material. NFT detection The most fundamental component of a SERS-based biosensor is its SERS substrate. It directly affects the

• SERS performance of the biosensor [6]. Herein, the Ag NPs-DES thin film with the superiorly uniform Ag NPs-DES coating can be used as a SERS substrate for the analysis of antibiotics. First, residue tracing of nitrofurantoin (NFT) has been conducted in the range from 10−3 M down to 10−8 M (Figure 4A

Silver-based SERS substrates fabricated using a 3D printed microfluidic device

• Phommachith Sonexai,
• Minh Van Nguyen,
• Bui The Huy and
• Yong-Ill Lee

Beilstein J. Nanotechnol. 2023, 14, 793–803, doi:10.3762/bjnano.14.65

• , resulting in Ag nanoparticles of uniform shape and size. The study investigates the effects of various synthesis conditions on the size distribution, dispersity, and localized surface plasmon resonance wavelength of the Ag nanoparticles. To create the SERS substrate, the as-synthesized Ag nanoparticles were

• and 8.21 × 103, respectively, were obtained. The detection limits for rhodamine B and melamine were estimated to be 1.94 × 10−10 M and 2.8 × 10−8 M with relative standard deviation values of 3.4% and 4.6%, respectively. The developed SERS substrate exhibits exceptional analytical performance and has

• the potential to be a valuable analytical tool for monitoring environmental contaminants. Keywords: 3D printing; microfluidic droplet; SERS substrate; silver nanoparticle; smartphone detection; Introduction Surface-enhanced Raman spectroscopy (SERS) has emerged as a powerful optical trace detection

SERS performance of GaN/Ag substrates fabricated by Ag coating of GaN platforms

• Magdalena A. Zając,
• Bogusław Budner,
• Malwina Liszewska,
• Bartosz Bartosewicz,
• Łukasz Gutowski,
• Jan L. Weyher and
• Bartłomiej J. Jankiewicz

Beilstein J. Nanotechnol. 2023, 14, 552–564, doi:10.3762/bjnano.14.46

• layer deposited at 50 °C is similar to that of the SERS substrate deposited at RT (Figure 3 – sample PLD_1_RT). However, a further increase in GaN platform temperature during deposition significantly changes the morphology of the fabricated GaN/Ag substrates. Spiky Ag structures are not formed, and the

• Figure 8, respectively. The colored lines represent the average spectra obtained for each SERS substrate, and the grey area represents the standard deviation of the average spectrum. Each spectrum was obtained by averaging the SERS spectra from at least 100 measurement points. The evaluation of the

• , which provide a greater enhancement of the Raman signal, consistent with the theory presented in numerous publications [40][41]. The SERS substrate made at 400 °C deviates from the visible trend as its EF is only 3.8 × 105. This observation correlates the most with the predicted highest degree of

Combining physical vapor deposition structuration with dealloying for the creation of a highly efficient SERS platform

• Adrien Chauvin,
• Walter Puglisi,
• Damien Thiry,
• Cristina Satriano,
• Rony Snyders and
• Carla Bittencourt

Beilstein J. Nanotechnol. 2023, 14, 83–94, doi:10.3762/bjnano.14.10

• use of Taro leaves or rose petals as substrates for silver PVD coating leads to a SERS detection limit down to 10−8 mol·L−1 and 10−9 mol·L−1, respectively, for rhodamine 6G (R6G) [55][56]. Moreover, the use of silver-coated paper as a SERS substrate reveals a detection limit down to 10−10 mol·L−1 for

Zinc oxide nanostructures for fluorescence and Raman signal enhancement: a review

• Ioana Marica,
• Fran Nekvapil,
• Maria Ștefan,
• Cosmin Farcău and
• Alexandra Falamaș

Beilstein J. Nanotechnol. 2022, 13, 472–490, doi:10.3762/bjnano.13.40

• relevant descriptors of any SERS substrate is the signal enhancement factor (EF), which describes the enhancement of the Raman signal of target molecules when adsorbed on the SERS substrate relative to the conventional Raman signal of the same number of molecules. The EF is generally calculated according

• decrease of the bandgap of ZnO. All of these are contributing to the SERS enhancement. A SERS substrate enhancement factor of 5.4 × 107 and an analytical enhancement factor of 1.3 × 1010 were obtained with Ag–ZnO heterostructures on glass substrates for the detection of methylene orange molecules. These

• approximately 10−9 M. Moreover, the study in [74] found a promising enhancement factor for a hollow ZnO–Ag nanosphere SERS substrate of 3.17 × 108 and a limit of detection of 0.3 × 10−8 M for nitrite species. Recyclable ZnO nanosubstrates Another motivating advantage of the ZnO-based plasmonic substrates refers

Modification of a SERS-active Ag surface to promote adsorption of charged analytes: effect of Cu²⁺ ions

• Bahdan V. Ranishenka,
• Andrei Yu. Panarin,
• Irina A. Chelnokova,
• Sergei N. Terekhov,
• Peter Mojzes and
• Vadim V. Shmanai

Beilstein J. Nanotechnol. 2021, 12, 902–912, doi:10.3762/bjnano.12.67

• charged hydrophilic thiols (sodium 2-mercaptoethyl sulfonate, mercaptopropionic acid, 2-mercaptoethanol, 2-(dimethylamino)ethanethiol hydrochloride, and thiocholine) to vary the surface charge of the SERS substrate. We used two oppositely charged porphyrins, cationic copper(II) tetrakis(4-N-methylpyridyl

• , we suppose EM is dominating in our work. Since the LSPR-enhanced electromagnetic field decays exponentially with the distance from the metal surface, the analyte molecules should be located near the surface of the SERS substrate to achieve maximum enhancement. However, close proximity is not optimal

• possible to exploit different techniques of functionalization. To avoid different effects related to the aggregation of NPs we used Ag NPs immobilized by adsorption as a convenient and reproducible SERS substrate for the investigation of the chemical treatment of the Ag surface with different reagents. To

On the stability of microwave-fabricated SERS substrates – chemical and morphological considerations

• Limin Wang,
• Aisha Adebola Womiloju,
• Christiane Höppener,
• Ulrich S. Schubert and
• Stephanie Hoeppener

Beilstein J. Nanotechnol. 2021, 12, 541–551, doi:10.3762/bjnano.12.44

• all substrates. Afterward, the SERS substrates were split in half. One half of the substrates was subjected to morphological investigations of particle structure and density by SEM. The other half of the SERS substrate was coated with a monolayer of 4-ATP, which serves as a test monolayer to evaluate

• times. From these results it was concluded that a complete monolayer of 4-ATP was formed on the silver nanoparticles. A reference spectrum of 4-ATP deposited on a freshly prepared, non-treated SERS substrate is depicted in Supporting Information File 1, Figure S5 and the corresponding peak assignment

• investigation of other buffer systems, a water-treated SERS substrate (1 h of immersion time) was used as the reference since all investigated buffer solutions are water based (Figure 2b and Supporting Information File 1, Figure S6; for the following discussion all Raman intensity deviations are referenced to

Surface-enhanced Raman scattering of water in aqueous dispersions of silver nanoparticles

• Paulina Filipczak,
• Krzysztof Hałagan,
• Jacek Ulański and
• Marcin Kozanecki

Beilstein J. Nanotechnol. 2021, 12, 497–506, doi:10.3762/bjnano.12.40

• average molecule numbers in a scattering volume for the SERS experiment conditions and for Raman scattering, respectively. The studied system herein is not a typical SERS system regarding the SERS substrate and the analysed substance (target molecule) in a low concentration. In our system, the solvent is

The influence of an interfacial hBN layer on the fluorescence of an organic molecule

• Christine Brülke,
• Oliver Bauer and
• Moritz M. Sokolowski

Beilstein J. Nanotechnol. 2020, 11, 1663–1684, doi:10.3762/bjnano.11.149

• , causing an enhancement by a factor of not more than 102–103 [46]. Recently, hBN has gained interest as a SERS substrate [49]. In a comparative study on 2DMs on SiO2 it was shown that hBN had an enhancement effect on the Raman modes of adsorbed copper phthalocyanine molecules [50]. The effect was explained

Fabrication of nano/microstructures for SERS substrates using an electrochemical method

• Jingran Zhang,
• Tianqi Jia,
• Xiaoping Li,
• Junjie Yang,
• Zhengkai Li,
• Guangfeng Shi,
• Xinming Zhang and
• Zuobin Wang

Beilstein J. Nanotechnol. 2020, 11, 1568–1576, doi:10.3762/bjnano.11.139

• electrochemical method, three-dimensional arrayed nanopore structures are machined onto a Mg surface. The structured Mg surface is coated with a thin gold (Au) film, which is used as a surface-enhanced Raman scattering (SERS) substrate. A rhodamine 6G (R6G) probe molecule is used as the detection agent for the

• /nanopore; nano/microstructures; SERS substrate; Introduction Surface-enhanced Raman spectroscopy (SERS) can be used to detect biomolecules [1][2][3], explosives [4][5][6], and pesticide residues [7][8][9]. Plasmonic metal nanostructures are often used as SERS substrates to increase the molecule-specific

• 5.5 × 106 with a reverse rate of 25 mV/s. Furthermore, pigments of Brilliant Blue FCF and Indigo Carmine at concentrations as low as 10−8 mol·L−1 and 10−7 mol·L−1, respectively, were detectable using the SERS substrate. Ou et al. [38] prepared Ag SERS substrates by using triangular-wave ORC procedures

Highly sensitive detection of estradiol by a SERS sensor based on TiO₂ covered with gold nanoparticles

• Andrea Brognara,
• Ili F. Mohamad Ali Nasri,
• Beatrice R. Bricchi,
• Andrea Li Bassi,
• Caroline Gauchotte-Lindsay,
• Matteo Ghidelli and
• Nathalie Lidgi-Guigui

Beilstein J. Nanotechnol. 2020, 11, 1026–1035, doi:10.3762/bjnano.11.87

• as SERS substrate for the detection of rhodamine 6G and other organic molecules. They obtained stable and reproducible results with a detection limit down to 10 µM, while also showing high recyclability through cleaning via UV irradiation. However, a main drawback of these methodologies is the use of

Label-free highly sensitive probe detection with novel hierarchical SERS substrates fabricated by nanoindentation and chemical reaction methods

• Jingran Zhang,
• Tianqi Jia,
• Yongda Yan,
• Li Wang,
• Peng Miao,
• Yimin Han,
• Xinming Zhang,
• Guangfeng Shi,
• Yanquan Geng,
• Zhankun Weng,
• Daniel Laipple and
• Zuobin Wang

Beilstein J. Nanotechnol. 2019, 10, 2483–2496, doi:10.3762/bjnano.10.239

• surface-enhanced Raman scattering (SERS) substrates. Recently, in order to obtain a higher enhancement factor at a lower detection limit, hierarchical structures, including nanostructures and nanoparticles, appear to be viable SERS substrate candidates. Here we describe a novel method integrating the

• nanoindentation process and chemical redox reaction to machine a hierarchical SERS substrate. The micro/nanostructures are first formed on a Cu(110) plane and then Ag nanoparticles are generated on the structured copper surface. The effect of the indentation process parameters and the corrosion time in the AgNO3

• solution on the Raman intensities of the SERS substrate with hierarchical structures are experimentally studied. The intensity and distribution of the electric field of single and multiple Ag nanoparticles on the surface of a plane and with multiple micro/nanostructures are studied with COMSOL software

The role of Ag⁺, Ca²⁺, Pb²⁺ and Al³⁺ adions in the SERS turn-on effect of anionic analytes

• Stefania D. Iancu,
• Andrei Stefancu,
• Vlad Moisoiu,
• Loredana F. Leopold and
• Nicolae Leopold

Beilstein J. Nanotechnol. 2019, 10, 2338–2345, doi:10.3762/bjnano.10.224

• species to the nanoparticle surface makes their SERS detection challenging since the most used SERS colloids contain anionic capping agents such as chloride or citrate. Table 1 summarizes several SERS studies of anionic species showing the detected anionic analyte, the concentration and the employed SERS

• substrate. It is clear from Table 1 that most studies regarding SERS detection of anionic analytes are reported in the millimolar concentration range. Particularly, the SERS spectrum of bilirubin [20] could be obtained at nanomolar concentration due to the resonance Raman supplementary enhancement mechanism

A silver-nanoparticle/cellulose-nanofiber composite as a highly effective substrate for surface-enhanced Raman spectroscopy

• Yongxin Lu,
• Yan Luo,
• Zehao Lin and
• Jianguo Huang

Beilstein J. Nanotechnol. 2019, 10, 1270–1279, doi:10.3762/bjnano.10.126

• Raman scattering (SERS) substrate was developed by facile deposition of silver nanoparticles onto cellulose fibers of ordinary laboratory filter paper. This was achieved by means of the silver mirror reaction in a manner to control both the size of the silver nanoparticles and the silver density of the

• substrate. This paper-based substrate is composed of a particle-on-fiber structure with the unique three-dimensional network morphology of the cellulose matrix. For such a SERS substrate with optimized size of the silver nanoparticles (ca. 70 nm) and loading density of silver (17.28 wt %), a remarkable

• . This low-cost, highly sensitive, and biocompatible paper-based SERS substrate holds considerable potentials for the detection and analyses of chemical and biomolecular species. Keywords: cellulose nanofiber; composites; nanoarchitectonics; silver nanoparticle; surface-enhanced Raman spectroscopy

Revisiting semicontinuous silver films as surface-enhanced Raman spectroscopy substrates

• Malwina Liszewska,
• Bogusław Budner,
• Małgorzata Norek,
• Bartłomiej J. Jankiewicz and
• Piotr Nyga

Beilstein J. Nanotechnol. 2019, 10, 1048–1055, doi:10.3762/bjnano.10.105

• , reflectance decreases for wavelengths in the range of about one micrometer) without the need for expensive and time-consuming structural characterization. This could be used as a quick method for initial optimization of SSF thickness for high SERS signal. Calculation of the SERS enhancement factor of a SERS

• substrate is extremely difficult since a proper reference sample is needed and there is an ongoing debate in the community regarding the appropriate procedures [59]. We decided to estimate the lower limit of the enhancement factor by adopting an approach similar to one used in the reference [20]. We

Fabrication of silver nanoisland films by pulsed laser deposition for surface-enhanced Raman spectroscopy

• Bogusław Budner,
• Mariusz Kuźma,
• Barbara Nasiłowska,
• Bartosz Bartosewicz,
• Malwina Liszewska and
• Bartłomiej J. Jankiewicz

Beilstein J. Nanotechnol. 2019, 10, 882–893, doi:10.3762/bjnano.10.89

• the results obtained with excitation at 532 nm. In summary, it should be noted that the EF calculation confirms the possibility of using silver nanoisland films deposited by the PLD method on silicon wafers as a SERS substrate. The SERS spectra of materials adsorbed on the surface of SERS substrates

• spectrum was taken as a result. The EF values for the SERS substrate were calculated taking into account coefficients of proportionality arising from different laser power and different measurement times. All spectra were background-corrected before EF calculation. Thickness of the silver nanoisland films

Biomimetic synthesis of Ag-coated glasswing butterfly arrays as ultra-sensitive SERS substrates for efficient trace detection of pesticides

• Guochao Shi,
• Mingli Wang,
• Yanying Zhu,
• Yuhong Wang,
• Xiaoya Yan,
• Xin Sun,
• Haijun Xu and
• Wanli Ma

Beilstein J. Nanotechnol. 2019, 10, 578–588, doi:10.3762/bjnano.10.59

• hybrids (Ag-G.b.) by magnetron sputtering technology. The 3D surface-enhanced Raman scattering (SERS) substrate is fabricated from an original chitin-based nanostructure, which serves as a bio-scaffold for Ag nanofilms to be coated on. The novel crisscrossing plate-like nanostructures of 3D Ag-G.b

• -density “hot spots” has become the biggest obstacle in the practical application of SERS detection. If a SERS substrate lacks dense “hot spots”, a long spectral acquisition time is required and the target species may be damaged. Two major approaches, wet-chemical or physical methods, are often adopted to

• , probe molecules can concentrate in a very small area after evaporation, resulting in relatively high SERS sensitivity [19]. Using the superhydrophobicity of the textured Taro leaf, Kumar and co-workers fabricated a novel SERS substrate and achieves a LOD value of 10−11 M for malachite green (MG) [20

Controlling surface morphology and sensitivity of granular and porous silver films for surface-enhanced Raman scattering, SERS

• Sherif Okeil and
• Jörg J. Schneider

Beilstein J. Nanotechnol. 2018, 9, 2813–2831, doi:10.3762/bjnano.9.263

• (RhB) was used as Raman probe to compare the performance of the different silver films. A 10−6 M solution of RhB was prepared in deionized water. A sufficient amount of this solution was dropped on the surface of the silver SERS substrates to cover the surface completely. The SERS substrate was left

• for 30 min in the aqueous RhB solution to enable the adsorption of the RhB on the silver surface. After that the SERS substrate was rinsed with deionized water to remove any excess of the RhB. The performance of the different SERS substrates was then evaluated through the measurement of the SERS

• in a spot size of about 0.8 µm. SERS spectra were collected using 1 s as integration time for single scans. For Raman mapping a 30 µm × 30 µm area was scanned, collecting 900 points (30 lines with 30 points each). The same parameters as for single scans were used. A commercial SERS substrate provided

The role of adatoms in chloride-activated colloidal silver nanoparticles for surface-enhanced Raman scattering enhancement

• Nicolae Leopold,
• Andrei Stefancu,
• Krisztian Herman,
• István Sz. Tódor,
• Stefania D. Iancu,
• Vlad Moisoiu and
• Loredana F. Leopold

Beilstein J. Nanotechnol. 2018, 9, 2236–2247, doi:10.3762/bjnano.9.208

• seems to prevail over the Raman enhancement due to nanoparticle aggregation. Keywords: chloride activation; electronic coupling; photoreduction; silver nanoparticles; SERS-active sites; SERS switch-on effect; Introduction The most common surface-enhanced Raman scattering (SERS) substrate is the silver

• colloid obtained by Ag+ reduction with citrate (cit-AgNPs), proposed by Lee and Meisel in 1982 [1]. Although the preparation of cit-AgNPs requires boiling conditions, this colloid is often preferred due to its high preparation success rate. Another often used SERS substrate is the silver colloid obtained

• + cations for the generation of SERS-active sites on the nanoparticle surface [28][29]. When using the cit-AgNPs as a SERS substrate, no SERS spectra of the dye molecules could be obtained since the Lee–Meisel colloid does not contain any chloride ions that could form SERS-active sites. Small amounts of Cl

Fabrication of gold-coated PDMS surfaces with arrayed triangular micro/nanopyramids for use as SERS substrates

• Jingran Zhang,
• Yongda Yan,
• Peng Miao and
• Jianxiong Cai

Beilstein J. Nanotechnol. 2017, 8, 2271–2282, doi:10.3762/bjnano.8.227

• the structures were successfully transferred to a polydimethylsiloxane (PDMS) surface using a reverse nanoimprinting approach. The structured PDMS surface is coated with a thin Au film, and the final substrate is demonstrated as a surface-enhanced Raman spectroscopy (SERS) substrate. Rhodamine 6G (R6G

• using imprint lithography. Several researchers have used biological organisms as biotemplates, such as the wings of cicadas [17][18] and butterflies [19][20][21]. A nanostructured SERS substrate was achieved for the replication of a biotemplate of a cicada wing and low concentrations of thiophenol and

• rhodamine 6G (R6G) were detected as test analytes [17]. The micro/nanostructures of a blue butterfly wing were used as a template, and a SERS substrate was produced and utilized to detect rhodamine dye for the elimination of organic pollutants [19]. Additionally, pyramidal array structures on conventional

Microfluidic setup for on-line SERS monitoring using laser induced nanoparticle spots as SERS active substrate

• Oana-M. Buja,
• Ovidiu D. Gordan,
• Nicolae Leopold,
• Andreas Morschhauser,
• Jörg Nestler and
• Dietrich R. T. Zahn

Beilstein J. Nanotechnol. 2017, 8, 237–243, doi:10.3762/bjnano.8.26

• -plane modes of phenyl-C-phenyl, in-plane modes of ring CH bending, N-phenyl stretching, and ring CC stretching, respectively [28], can be observed in Figure 1b in the blue spectra. In order to remove MG from the silver surface and to regenerate the SERS substrate, silver/citrate solution was injected

• and no SERS signal of MG was observed anymore. Conclusion We reported a straightforward approach for on-line preparation of silver and gold nanoparticle spots as SERS active substrates, which was used for fast detection of the model compound MG. By using silver or gold spots as SERS substrate, the

• SERS signal is reached, and finally, the desorption of MG from the spot. Moreover, after MG complete desorption, the regeneration of the SERS active spot was achieved. The detection of MG was possible down to 10−7 M concentration with a good reproducibility when using silver or gold spots as SERS

Surface-enhanced Raman scattering of self-assembled thiol monolayers and supported lipid membranes on thin anodic porous alumina

• Marco Salerno,
• Amirreza Shayganpour,
• Barbara Salis and
• Silvia Dante

Beilstein J. Nanotechnol. 2017, 8, 74–81, doi:10.3762/bjnano.8.8

• ), and then with phospholipid vesicles of different composition to form a supported lipid bilayer (SLB). At each step, the SERS substrate functionality was assessed, demonstrating acceptable enhancement (≥100×). The chemisorption of thiols during the first step and the formation of SLB from the vesicles

Sandwich-like layer-by-layer assembly of gold nanoparticles with tunable SERS properties

• Zhicheng Liu,
• Lu Bai,
• Guizhe Zhao and
• Yaqing Liu

Beilstein J. Nanotechnol. 2016, 7, 1028–1032, doi:10.3762/bjnano.7.95

• Ibulk are the intensity of a vibrational mode in the SERS spectrum and bulk sample, and Nads and Nbulk are the number of molecules adsorbed on the SERS substrate and bulk molecules excited by the laser, respectively. Using the 1587 cm−1 band, the EF values for the SSS, SBS, BSB and BBB thin films are

• films. Conclusion Sandwich-like LbL assemblies of Au NPs were designed as model SERS substrate. The SERS performance could be readily tuned by using Au NPs of different sizes or introducing insert layers with controllable thickness. The methods and strategies involved in this work are rather simple. The

Chemiresistive/SERS dual sensor based on densely packed gold nanoparticles

• Sanda Boca,
• Cosmin Leordean,
• Simion Astilean and
• Cosmin Farcau

Beilstein J. Nanotechnol. 2015, 6, 2498–2503, doi:10.3762/bjnano.6.259

• , respectively [15][16]. This is an indication for the adsorption of MBA molecules. These bands were observed also in control experiments performed on another kind of gold SERS substrate without capping ligands such as folic acid on the NPs (see Supporting Information File 1). Some less intense bands, e.g., at

• online analyte injection, which we might tackle in the near future. Conclusion This work demonstrated the proof-of-concept of a nanoparticle-based dual-mode (bio)chemo-sensor capable of working as both chemiresistor and SERS substrate. At the heart of the proposed DEOS lie strips of gold nanoparticles

Protein corona – from molecular adsorption to physiological complexity

• Lennart Treuel,
• Dominic Docter,
• Michael Maskos and
• Roland H. Stauber

Beilstein J. Nanotechnol. 2015, 6, 857–873, doi:10.3762/bjnano.6.88

• ][126]. In the context of protein adsorption, it needs to be pointed out that the enhancement effect in SERS strongly depends on the distance between the Raman/SERS active bond and the surface of the SERS substrate [121][123][124][125][126][127]. An intriguing aspect in the work of Grass and Treuel [36