Adsorption of dipeptide L-alanyl-L-tryptophan on gold colloidal nanoparticles studied by surface-enhanced Raman spectroscopy

Lee, Daedu; Hussain, Shafqat; Yeo, Juhyun; Pang, Yoonsoo

doi:10.1016/j.saa.2020.119064

Cited by 13 publications

(12 citation statements)

References 53 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The reference RS and FT-IR spectra of the dried Trp solution (10 −2 M Trp/PBS, pH 3.0) are shown in Figures 4a and 5a, respectively. The proposed band assignments were based on many theoretical and experimental data from the literature on the molecular structure of Trp and Trp derivatives obtained under various conditions [42,[52][53][54][55][56][57][58][59][60][61][62][63][64][65][66]. As mentioned in our previous paper [28], the preparation of samples for experiments may affect the information obtained from spectral patterns (i.e., the state of the sample condition, pH of the surrounding environment).…”

Section: Spectroscopic Results Of the Surface Adsorption Geometry Of Tryptophan On Corroded 316l Stainless Steelmentioning

confidence: 99%

Spectroscopic Investigations of 316L Stainless Steel under Simulated Inflammatory Conditions for Implant Applications: The Effect of Tryptophan as Corrosion Inhibitor/Hydrophobicity Marker

et al. 2021

View full text Add to dashboard Cite

In this paper, the conformational changes of tryptophan (Trp) on the corroded 316 L stainless steel (SS) surface obtained under controlled simulated inflammatory conditions have been studied by Raman (RS) and Fourier-transform infrared (FT-IR) spectroscopy methods. The corrosion behavior and protective efficiency of the investigated samples were performed using the potentiodynamic polarization (PDP) technique in phosphate-buffered saline (PBS) solution acidified to pH 3.0 at 37 °C in the presence and absence of 10−2 M Trp, with different immersion times (2 h and 24 h). The amino acid is adsorbed onto the corroded SS surface mainly through the lone electron pair of the nitrogen atom of the indole ring, which adopts a more/less tilted orientation, and the protonated amine group. The visible differences in the intensity of the Fermi doublet upon adsorption of Trp onto the corroded SS surface, which is a sensitive marker of the local environment, suggested that a stronger hydrophobic environment is observed. This may result in an improvement of the corrosion resistance, after 2 h than 24 h of exposure time. The electrochemical results confirm this statement—the inhibition efficiency of Trp, acting as a mixed-type inhibitor, is made drastically higher after a short period of immersion.

show abstract

Section: Spectroscopic Results Of the Surface Adsorption Geometry Of Tryptophan On Corroded 316l Stainless Steelmentioning

confidence: 99%

Spectroscopic Investigations of 316L Stainless Steel under Simulated Inflammatory Conditions for Implant Applications: The Effect of Tryptophan as Corrosion Inhibitor/Hydrophobicity Marker

et al. 2021

View full text Add to dashboard Cite

show abstract

“…Benzene ring stretch and CCH deformation which is observed at 1355 cm −1 for Ag1 and at 1365 cm −1 for Ag2 are enhanced and observed at 1373 cm −1 in the calculated spectrum. Similarly, mixedmode having a contribution from CH 2 wag, NH 2 rock, and CHO deformation present at 1340 cm −1 in both experimental and calculated spectra is enhanced [25,[56][57][58].…”

Section: Computational Analysismentioning

confidence: 77%

“…The bands at 760 cm −1 , 878 cm −1, and 1012 cm −1 showed prominent enhancement which corresponds to 763 cm −1 , 881 cm −1, and 1024 cm −1 in the calculated SERS spectrum. The band at 760 cm −1 is assigned as the puckering and deformation mode of the benzene ring, the indole ring deformation, stretching, and NH 2 out of plane vibration are observed at 878 cm −1 and the band at 1012 cm −1 is assigned to the benzene ring stretching and deformation [25,[56][57][58]. As discussed earlier, vibrational modes with their z-component of polarizability tensor perpendicular to the metal surface are enhanced more suggesting that the indole ring of the Tryptophan molecule reclines with the z-component of the polarizability tensor perpendicular to the metal surface in the present experimental conditions [23].…”

Section: Computational Analysismentioning

confidence: 99%

Characterization of Aggregating Agents towards Sensitive Optical Detection of Tryptophan Using Lab-on-a-Chip

et al. 2022

View full text Add to dashboard Cite

The analysis of body fluids is desirable to minimize the invasiveness of diagnostic tests and non-destructive forensic investigations. In this study, surface-enhanced Raman spectroscopy (SERS) is employed for sensitive and reproducible detection of biomolecule focusing on ‘hot spots’ generation and automated flow system. Here, we have demonstrated how the plasmon frequency of nanoparticles can be tuned using different aggregating agents for optimal SERS signals. We have compared the effect of different aggregating agents on silver colloids and the resulting enhancement in Raman signals for Tryptophan which is an important amino acid present as an integral component of various body fluids including blood, saliva, tears, and cerebrospinal fluid. The automated segmented flow system, Lab-on-a-chip (LOC), is employed to trap the analyte in droplets while obtaining reproducible SERS spectra of Tryptophan at μM concentration. Further for a thorough interpretation of enhanced vibrational modes of Tryptophan, a theoretical approach has been applied. By combining both experimental and computational approaches we have identified the most preferable site of Tryptophan for interaction with metal nanoparticles and accurately assigned the enhanced Raman bands. The present study demonstrates that the union of SERS and microfluidics has the potential for spectral fingerprinting of biomolecules present in body fluids with high sensitivity.

show abstract

“…[1][2][3] Generally, it is believed that two mechanisms contribute the SERS enhancement, one being the electromagnetic effect generated by optical excitation of surface plasmons on metal surface and second is the chemical effect which arise due to charge transfer (CT) between analyte and metal surface. [4,5] Until now, it remains a challenge to synthesize active substrate with a large SERS enhancement factor. Noble metals (Ag, Au and Cu) are considered as best candidates for fabrication of SERS substrates due to their strong interaction with excitation of localized surface plasmon resonance (LSPR) that could be tuned in UV, visible and near IR region.…”

Section: Introductionmentioning

confidence: 99%

“…Surface‐enhanced Raman Scattering (SERS), a powerful tool to overcome low sensitivity problem inherent in Raman spectroscopy has demanding applications in the fields of chemistry, material science, medicine and biosensing [1–3] . Generally, it is believed that two mechanisms contribute the SERS enhancement, one being the electromagnetic effect generated by optical excitation of surface plasmons on metal surface and second is the chemical effect which arise due to charge transfer (CT) between analyte and metal surface [4,5] . Until now, it remains a challenge to synthesize active substrate with a large SERS enhancement factor.…”

Section: Introductionmentioning

confidence: 99%

Tuning the SERS Capabilities of ZnO Nanowire Arrays Functionalized with Au Quantum Dots for Highly Sensitive Detection of Methylene Blue

et al. 2023

Self Cite

View full text Add to dashboard Cite

The development of a surface enhanced Raman scattering (SERS) substrate capable of sensing the target analyte at low concentration has always been demanding. In this prospective, ZnO−Au quantum dots (QDs) hybrid structure with tunable surface properties and high chemical stability is considered a promising material for SERS applications. Here, a novel ZnO@Au QDs hybrid structures with various amounts of Au QDs (ZnO−Aux QDs, where x=0.2, 0.4, 0.6 and 1.0) was synthesized by employing solvothermal along with electrodeposition approach. The optimized substrate, ZnO@Au QDs (0.6) exhibits excellent SERS sensitivity for the detection of MB up to 1 nM with a good reproducibility. The chemical and compositional analysis show that the surface defects are formed due to the interface interactions which not only promote charge transfer between ZnO nanowires and Au QDs complex but also enhanced the Raman scattering of target analyte. The developed substrate demonstrates excellent SERS uniformity which makes them reliable choice for the detection of multi‐analyte for practical applications.

show abstract

Adsorption of dipeptide L-alanyl-L-tryptophan on gold colloidal nanoparticles studied by surface-enhanced Raman spectroscopy

Cited by 13 publications

References 53 publications

Spectroscopic Investigations of 316L Stainless Steel under Simulated Inflammatory Conditions for Implant Applications: The Effect of Tryptophan as Corrosion Inhibitor/Hydrophobicity Marker

Spectroscopic Investigations of 316L Stainless Steel under Simulated Inflammatory Conditions for Implant Applications: The Effect of Tryptophan as Corrosion Inhibitor/Hydrophobicity Marker

Characterization of Aggregating Agents towards Sensitive Optical Detection of Tryptophan Using Lab-on-a-Chip

Tuning the SERS Capabilities of ZnO Nanowire Arrays Functionalized with Au Quantum Dots for Highly Sensitive Detection of Methylene Blue

Contact Info

Product

Resources

About