Facile synthesis of size-tunable L-carnosine-capped silver nanoparticles and their role in metal ion sensing and catalytic degradation of p-nitrophenol

• Akash Kumar,
• Ridhima Chadha,
• Abhishek Das,
• Nandita Maiti and
• Rayavarapu Raja Gopal

Beilstein J. Nanotechnol. 2024, 15, 1576–1592, doi:10.3762/bjnano.15.124

• ʟ-carnosine in aqueous solution compared to those in the solid is probably due to solvent effects. Figure 4c shows surface-enhanced Raman spectra (SERS) of ʟ-carnosine-capped silver nanoparticles. The signal-to-noise (S/N) ratio follows the order ʟ-car-AgNP4 > ʟ-car-AgNP3 > ʟ-car-AgNP2 > ʟ-car-AgNP1

• > ʟ-car-AgNP5. Therefore, the results show maximum SERS enhancement for AgNP4. This is probably because of the greater surface roughness of the nanoparticles, leading to maximum electromagnetic enhancement in AgNP4. The SERS spectra of the ʟ-car-AgNPs are almost similar and show Raman bands at 1623 cm

• (NH2 twist) and 215 cm−1 (Ag–O stretching). The observation of the abovementioned prominent peaks in the SERS spectra confirms the capping of silver nanoparticles with ʟ-carnosine. The SERS enhancement observed in various vibrations associated with imidazole ring, CO2, and NH2 groups suggests that, at

Effect of wavelength and liquid on formation of Ag, Au, Ag/Au nanoparticles via picosecond laser ablation and SERS-based detection of DMMP

• Sree Satya Bharati Moram,
• Chandu Byram and
• Venugopal Rao Soma

Beilstein J. Nanotechnol. 2024, 15, 1054–1069, doi:10.3762/bjnano.15.86

• -dispersive X-ray spectroscopy. Furthermore, NPs of various sizes ranging from 6 to 35 nm were loaded onto a filter paper by a simple and effective drop-casting approach to achieve flexible surface-enhanced Raman spectroscopy (SERS) substrates/sensors. These substrates were tested using a simple, portable

• Raman device to identify various hazardous chemicals (malachite green, methyl salicylate, and thiram). The stability of the substrates was also systematically investigated by determining the decay percentages in the SERS signals over 60 days. The optimized SERS substrate was subsequently employed to

• detect chemical warfare agent (CWA) simulants such as methyl salicylate (a CWA simulant for sulfur mustard) and dimethyl methyl phosphonate (has some structural similarities to the G-series nerve agents) at different laser excitations (325, 532, and 633 nm). A notably higher SERS efficiency for CWA

Gold nanomakura: nanoarchitectonics and their photothermal response in association with carrageenan hydrogels

• Nabojit Das,
• Vikas,
• Akash Kumar,
• Sanjeev Soni and
• Raja Gopal Rayavarapu

Beilstein J. Nanotechnol. 2024, 15, 678–693, doi:10.3762/bjnano.15.56

• -known noble metal materials whose resonance occurs in both visible and infrared range of the electromagnetic spectrum, rendering pertinence in various disciplines such as surface-enhanced Raman scattering (SERS), optical sensors, fluorescence (SPR) sensor chips, deoxyribonucleic acid (DNA) sensors

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

• Ag NPs-DES sample is used in a surface-enhanced Raman scattering (SERS) sensor. The two analytes for SERS quantitation are nitrofurantoin (NFT) and sulfadiazine (SDZ) whose residues can be traced down to 10−8 M. The highest enhancement factors (EFs) are competitive at 6.29 × 107 and 1.69 × 107 for

• 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

• synthesis of nanomaterials for biosensor substrate construction. Keywords: Ag NPs; antibiotic residue; deep eutectic solvents; potential; SERS; Introduction Surface-enhanced Raman scattering (SERS) is a ubiquitous technology for detecting and tracing substances, applied in various kinds of sensors. The

Nanoarchitectonics of photothermal materials to enhance the sensitivity of lateral flow assays

• Elangovan Sarathkumar,
• Rajasekharan S. Anjana and
• Ramapurath S. Jayasree

Beilstein J. Nanotechnol. 2023, 14, 988–1003, doi:10.3762/bjnano.14.82

• spectroscopy (SERS), fluorescence, ultrasound, and photothermal methods, have been tried in LFAs [4][13][14]. For example, fluorescence-based LFAs exhibited a 100- to 1000-fold higher sensitivity than conventional LFAs [15]. However, working with fluorescence-based LFAs is complex because of photoinstability

• , SERS, fluorescence, and photothermal applications [45]. For instance, compared to spherical architectures, anisotropic nanoscale architectures, such as nanostars, nanoflowers, nanopopcorns, nanorods, and nanocages, exhibit superior SERS and photothermal conversion activities [46][47]. Therefore, it is

• has advantages such as high NIR absorption, large surface area, and biocompatibility. Also, it is known to enhance the signal intensity in SERS, albeit less efficiently than gold nanoparticles [82][83]. However, graphene can be used for photothermal applications. Using a hybrid formulation of gold and

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

• detection of harmful chemicals in the environment and for food safety is a crucial requirement. While traditional techniques such as GC–MS and HPLC provide high sensitivity, they are expensive, time-consuming, and require skilled labor. Surface-enhanced Raman spectroscopy (SERS) is a powerful analytical

• tool for detecting ultralow concentrations of chemical compounds and biomolecules. We present a reproducible method for producing Ag nanoparticles that can be used to create highly sensitive SERS substrates. A microfluidic device was employed to confine the precursor reagents within the droplets

• , 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

Metal-organic framework-based nanomaterials as opto-electrochemical sensors for the detection of antibiotics and hormones: A review

• Akeem Adeyemi Oladipo,
• Saba Derakhshan Oskouei and
• Mustafa Gazi

Beilstein J. Nanotechnol. 2023, 14, 631–673, doi:10.3762/bjnano.14.52

• (ELISA), radioimmunoassay (RIA), surface-enhanced Raman spectroscopy (SERS), and capillary electrophoresis are common analytical techniques used to qualitatively or quantitatively determine pharmaceuticals in various matrices because they are sensitive (Figure 2), have a significant tolerable limit of

• limited resources. Additionally, the mobile phase utilized in the separation of antibiotics and hormones affects the chromatography’s ability to detect substances [23]. The advantages of SERS are its rapid detection time, affordable detection cost, and ease of use. It also has a number of drawbacks, such

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

• substrates using pulsed laser deposition (PLD) and magnetron sputtering (MS) and their evaluation as potential substrates for surface-enhanced Raman spectroscopy (SERS) are reported. Ag layers of comparable thicknesses were deposited using PLD and MS on nanostructured GaN platforms. All fabricated SERS

• substrates were examined regarding their optical properties using UV–vis spectroscopy and regarding their morphology using scanning electron microscopy. SERS properties of the fabricated GaN/Ag substrates were evaluated by measuring SERS spectra of 4-mercaptobenzoic acid molecules adsorbed on them. For all

• : GaN/Ag; magnetron sputtering; nanofabrication; pulsed laser deposition; SERS substrates; surface-enhanced Raman spectroscopy (SERS); Introduction Surface-enhanced Raman spectroscopy (SERS) is a highly sensitive and specific technique with multiplexing capabilities [1][2][3][4]. It is considered for

Plasmonic nanotechnology for photothermal applications – an evaluation

• A. R. Indhu,
• L. Keerthana and
• Gnanaprakash Dharmalingam

Beilstein J. Nanotechnol. 2023, 14, 380–419, doi:10.3762/bjnano.14.33

• use in PT applications, while its use in a novel synthesis strategy for SERS-enhancing self-assembled nanoparticles is worth mentioning [105]. Though details about the absence of thermal phenomena for plasmonic nanobubble formation are yet to be confirmed, the important conclusion that increasing the

Characterisation of a micrometer-scale active plasmonic element by means of complementary computational and experimental methods

• Ciarán Barron,
• Giulia Di Fazio,
• Samuel Kenny,
• Silas O’Toole,
• Robin O’Reilly and
• Dominic Zerulla

Beilstein J. Nanotechnol. 2023, 14, 110–122, doi:10.3762/bjnano.14.12

• fundamental physical phenomena at the nano- and mesoscales [9][10][11][12][13][14][15], as well as more practical applications in Raman spectroscopy in the form of surface-enhanced Raman spectroscopy (SERS) [16] and other spectroscopic techniques [17][18]. SPPs also find uses in fields such as ultrasensitive

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

• Nanostructured noble metal thin films are highly studied for their interesting plasmonic properties. The latter can be effectively used for the detection of small and highly diluted molecules by the surface-enhanced Raman scattering (SERS) effect. Regardless of impressive detection limits achieved, synthesis

• complexity and the high cost of gold restrict its use in devices. Here, we report on a novel two-step approach that combines the deposition of a silver–aluminum thin film with dealloying to design and fabricate efficient SERS platforms. The magnetron sputtering technique was used for the deposition of the

• tuning deposition (i.e., the alloy chemical composition) and dealloying (i.e., dealloying media) parameters to reach the best SERS properties. These are reported for samples dealloyed in HCl and with 30 atom % of silver at the initial state with a detection limit down to 10−10 mol·L−1 for a solution of

Studies of probe tip materials by atomic force microscopy: a review

• Ke Xu and
• Yuzhe Liu

Beilstein J. Nanotechnol. 2022, 13, 1256–1267, doi:10.3762/bjnano.13.104

• Raman enhanced scattering (SERS) probes and used them to detect bisphenol A (BPA) in water. The experimental results showed that the colloidal fiber probes could detect 10−8 M BPA in water. This method of preparing colloidal fibers is simple and easy to operate and can be prepared on a large scale

• , providing new opportunities for many fields. In practical applications, due to the surface structure of colloidal fibers, these fibers can be used as SERS sensor detection for trace detection of BPA. Although colloidal probes have many excellent properties, there are some problems in calibrating such probes

Revealing local structural properties of an atomically thin MoSe₂ surface using optical microscopy

• Lin Pan,
• Peng Miao,
• Anke Horneber,
• Alfred J. Meixner,
• Pierre-Michel Adam and
• Dai Zhang

Beilstein J. Nanotechnol. 2022, 13, 572–581, doi:10.3762/bjnano.13.49

• molybdenum diselenide (MoSe2) flake as surface-enhanced Raman spectroscopy (SERS) platform, we demonstrate the dependency of the Raman enhancement on laser beam polarization and local structure using copper phthalocyanine (CuPc) as probe. Second harmonic generation (SHG) and photoluminescence spectroscopy

• between structural irregularities and properties of 2D-TMDC materials has been intensively explored recently. Surface-enhanced Raman spectroscopy (SERS) has been used as an ultrasensitive and nondestructive spectroscopic technique for fundamental investigations of light–matter interactions down to the

• , including graphene and 2D-TMDC materials, are unique platforms for SERS investigations based on the chemical mechanism [21]. Recently, enhanced Raman signals of rhodamine 6G (R6G) molecules on an oxygen plasma-treated MoS2 flake were reported, because the symmetry of the R6G molecule can be modified through

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

• , Romania RDI Laboratory of Applied Raman Spectroscopy, RDI Institute of Applied Natural Sciences (IRDI-ANS), Babeş-Bolyai University, Fântânele 42, 400293, Cluj-Napoca, Romania 10.3762/bjnano.13.40 Abstract Since the initial discovery of surface-enhanced Raman scattering (SERS) and surface-enhanced

• surface features, and the specific location of analyte molecules. Lately, ZnO-based nanostructures have been exploited especially as SERS substrates showing high enhancement factors and increased charge transfer effect. Additionally, applications focused on enhancing the fluorescence of analyte molecules

• synthesis methods are discussed, highlighting low-cost methods and the recyclability of ZnO-based nanosubstrates. Also, the SERS signal enhancement by ZnO-based nanostructures and the influences of lattice defects on the SERS signal are described. The photoluminescence enhancement of ZnO in the presence of

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

• -enhanced Raman scattering (SERS) when doped with rhodamine B (RhB). The enhancement factor produced by these gold nanoflowers was estimated to be 1.09 × 105 regarding pure RhB. The value of the enhancement factor is up to par with the intensively branched gold nanoparticles and is even greater than some of

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

• the electrostatic interaction between analyte molecules and silver nanoparticles (Ag NPs) on the intensity of surface-enhanced Raman scattering (SERS). For this, we fabricated nanostructured plasmonic films by immobilization of Ag NPs on glass plates and functionalized them by a set of differently

• 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

• ) porphine (CuTMpyP4) and anionic copper(II) 5,10,15,20-tetrakis(4-sulfonatophenyl)porphine (CuTSPP4), with equal charge value and similar structure as model analytes to probe the SERS signal. Our results indicate that the SERS spectrum intensity strongly, up to complete signal disappearance, correlates with

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

• spectroscopy (SERS) substrates in different organic solvents and different buffer solutions was investigated. SERS substrates were fabricated by a microwave-assisted synthesis approach and the morphological as well as chemical changes of the SERS substrates were studied. It was demonstrated that the SERS

• sulfoxide (DMSO) treatment completely preserved or even slightly improved the Raman enhancement capabilities. SERS substrates immersed into phosphate-buffered saline (PBS) solutions were observed to be rather instable in low and neutral pH buffer solutions. Other buffer systems showed less severe influences

• on the SERS activity of the substrates and a carbonate buffer at pH 10 was found to even improve SERS performance. This study represents a guideline on the stability of microwave-fabricated SERS substrates or other SERS substrates consisting of non-stabilized silver nanoparticles for the application

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

• Raman scattering (SERS) effect. In this work, we show the SERS effect for water molecules in the dispersion of silver nanoparticles (AgNPs) without any external electrical field. An enhancement factor was estimated to be (4.8 ± 0.8) × 106 for an excitation wavelength of 514.5 nm and for AgNPs with an

• effect weaker [20]. Silver nanoparticles (AgNPs) are gaining more and more popularity in various applications, such as electronics [22], photonics [23], and medicine [24]. Silver nanocolloids are also commonly used as an enhancing substrate in surface-enhanced Raman scattering (SERS) [25][26]. Since the

• discovery of the SERS effect in 1974 [27], most of the research is focused on biomolecules and medical applications [28][29]. The SERS effect of water has been studied since 1980. There are reports on the SERS effect of water in aqueous solutions of electrolytes placed between metal electrodes (Ag, Au, Cu

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

• small quantity of molecules can be observed here at all is attributed to surface-enhanced Raman scattering (SERS) [45]. This effect is most commonly observed on rough surfaces of noble metals [45] or at metal nanostructures [46], and it is utilized in surface-enhanced Raman spectroscopy [47]. There are

• , 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

• that the energy of the SPP of Cu(111), which is calculated from the condition [51] using the dielectric functions given in [52], is obtained at a value of = 2.3 eV. Our excitation energy was 2.698 eV. From our experiment we have indeed evidence that SERS is related to surface defects. This will be

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

• SERS measurement. Different sizes of arrayed micro/nanostructures are fabricated by different treatment time using the electrochemical process. The topographies of these micro/nanostructures and the thickness of the Au film have an influence on the Raman intensity of the Mg substrate. Furthermore, when

• the thickness of Au film coating is held constant, the Raman intensity on the structured Mg substrates is about five times higher after a treatment time of 1 min when compared with other treatment times. The SERS enhancement factor ranges from 106 to 1.75 × 107 under these experimental conditions

Optically and electrically driven nanoantennas

• Monika Fleischer,
• Dai Zhang and
• Alfred J. Meixner

Beilstein J. Nanotechnol. 2020, 11, 1542–1545, doi:10.3762/bjnano.11.136

• spectroscopy (SERS); tip-enhanced Raman spectroscopy (TERS); tunnel junction; Editorial Optical antennas + serve to confine the energy of photons transported by a light wave to a tiny volume much smaller than the wavelength; or reversely, to convert the energy of an evanescent field that oscillates at optical

• configurations with increasing control over their optical performance [1][2][3][4]. The strong local near-field enhancement by plasmonic nanoantennas is being harnessed for high sensitivity, high-resolution optical nanospectroscopy techniques [5], such as surface-enhanced or tip-enhanced Raman spectroscopy (SERS

• . Prominent examples are SERS and TERS, where the intrinsically small Raman scattering cross-section is enhanced by several orders of magnitude, making single-molecule spectroscopy feasible. These spectroscopic techniques have shown tremendous progress in the last two decades [29][30][31][32]. Under high

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

• -enhanced Raman scattering (SERS) sensors for the detection of 17β-estradiol. Gold deposition on top of a TiO2 surface leads to the formation of nanoparticles the plasmonic properties of which fulfil the requirements of a SERS sensor. The morphological and optical properties of the surface were investigated

• (SERS); TiO2 nanostructures; Introduction Surface-enhanced Raman scattering (SERS) as a sensing tool requires the optimization of a surface and its functionalization. The surface should provide a good enhancement over a large range of wavelengths, to detect molecules with various fingerprints, while it

• water. SERS is mainly based on an electromagnetic effect that originates from the excitation of plasmon resonances, in particular of localized surface plasmons (LSPs) in metallic nanoparticles (NPs). Other effects may contribute to the enhancement such as the formation of hot spots or lightning rod

Evolution of Ag nanostructures created from thin films: UV–vis absorption and its theoretical predictions

• Robert Kozioł,
• Marcin Łapiński,
• Paweł Syty,
• Damian Koszelow,
• Wojciech Sadowski,
• Józef E. Sienkiewicz and
• Barbara Kościelska

Beilstein J. Nanotechnol. 2020, 11, 494–507, doi:10.3762/bjnano.11.40

• field is extremely important is surface-enhanced Raman scattering (SERS), where Raman spectra can be enhanced by several orders of magnitude. However, there are many other areas where it is possible to increase the efficiency of equipment by increasing the electromagnetic field around metal

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

• -Napoca, Romania 10.3762/bjnano.10.224 Abstract In our recent studies we highlighted the role of adsorbed ions (adions) in turning on the surface-enhanced Raman scattering (SERS) effect in a specific mode for anionic and cationic analytes. In this work, we emphasize the role of Ag+, Ca2+, Pb2+ and Al3

• adsorption sites specific for the anionic analytes. The turn-on of the SERS effect is explained in the context of the chemical mechanism of SERS. The adions form SERS-active sites on the silver surface enabling a charge transfer between the adsorbate and the silver surface. High-intensity SERS spectra of

• of higher affinities to the silver surface as indicated by the SERS spectra of corresponding mixed solutions. Keywords: adion-specific adsorption model; cation bridging; Raman; surface enhanced Raman scattering (SERS); Introduction Surface-enhanced Raman scattering (SERS) is an ultrasensitive