Surface resonance Raman and surface-enhanced Raman scattering excitation profiles for dabsyl aspartate on colloidal silver in ethanol

Lepp, Adam; Siiman, Olavi

doi:10.1021/j100262a015

Cited by 14 publications

(8 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The four components of the polymeric films are Raman active species, as reported elsewhere [25,26,27,28], where PAR and PVP show notorious band-rich spectra. However, its SERS behavior has been mainly reported for PAR and less for the polymeric compounds.…”

Section: Sers and Raman Spectrasupporting

confidence: 57%

SERS hyperspectral imaging assisted by MCR-ALS for studying polymeric microfilms loaded with paracetamol

Mamián-López

Poppi

2015

Microchemical Journal

View full text Add to dashboard Cite

In this study, a combination of the high detectability and specificity of the SERS technique with powerful chemometric tools was used to obtain hyperspectral images in order to assess the chemical distribution of the components of polymeric microfilms loaded with paracetamol as active principle. Four microfilms with drug content ranging between 5.42 and 18.62% were fabricated directly over nanostructured gold substrates and spectra were acquired over an area of 4 × 4 mm. Chemical images were first built following a qualitative approach by applying principal component analysis (PCA) and calculating correlation coefficients. With the algorithm multivariate curve resolution-alternating least squares (MCR-ALS), the mean concentrations of all components were calculated with relative error values between 3.5 and 4.9% for paracetamol. With the proposed methodology, both qualitative and quantitative assessments of the distribution of constituents of polymeric microfilms were successfully performed. In addition, physical-chemistry interactions among them could be also analyzed.

show abstract

Section: Sers and Raman Spectrasupporting

confidence: 57%

SERS hyperspectral imaging assisted by MCR-ALS for studying polymeric microfilms loaded with paracetamol

Mamián-López

Poppi

2015

Microchemical Journal

View full text Add to dashboard Cite

show abstract

“…Platinum nanocrystals capped with PVP absorb strongly at 244 nm while pure PVP does not exhibit perceptible absorption (Figure ). Recently it was shown that the UV−vis spectrum of the PVP/Pt exhibits absorption at 215 nm as a result of an interband (d-sp) transition with a small contribution from plasmon oscillations, and a second absorption band near 260 nm assigned to clusters of nanoparticles 9a. The resonance Raman enhancement of vibrational modes of the amide group and ring vibrations observed here indicates that the 244 nm excitation line lies within the absorption band that originates from charge transfer (CT) between Pt and the pyrrolidone rings of PVP, although its strength may be too low for detection …”

Section: Resultsmentioning

confidence: 99%

“…However, very little is known about the structure and nature of the chemical bond between PVP and platinum nanocrystals at the molecular level. Different experimental techniques have been used to explore the interface of PVP/Pt including XPS, UV−vis,9a FTIR, and Raman spectroscopy 9b 1 Schematic illustration of PVP/Pt nanoparticles with different structure (morphology) of capping polymeric macroligand: (A) low molecular weight PVP, (B) high molecular weight PVP, and (C) dense, cross-linked PVP. …”

Section: Introductionmentioning

confidence: 99%

Probing the Interaction of Poly(vinylpyrrolidone) with Platinum Nanocrystals by UV−Raman and FTIR

et al. 2006

View full text Add to dashboard Cite

The vibrational spectra of platinum nanoparticles (2.4-9 nm) capped with poly(N-vinylpyrrolidone) (PVP) were investigated by deep UV-Raman and FTIR spectroscopy and compared with those of pure PVP. Raman spectra of PVP/Pt show selective enhancement of C=O, C-N, and CH2 vibrational modes attributed to the pyrrolidone ring. Selective enhancement of ring vibrations is attributed both to the resonance Raman effect and SERS chemical enhancement. A red shift of the PVP carbonyl frequency on the order of 60 cm-1 indicates the formation of strong >C=O-Pt bonds. It is concluded that PVP adheres to the nanoparticles through a charge-transfer interaction between the pyrrolidone rings and surface Pt atoms. Heating the Pt nanoparticles under reducing conditions initiates the decomposition of the capping agent, PVP, at a temperature 100 degrees C below that of pure PVP. Under oxidizing conditions, both PVP/Pt and PVP degrade to form amorphous carbon.

show abstract

“…The nanoparticles (both AuNG and AuNC) underwent a ligand exchange process to replace their polyvinylpyrrolidone (PVP) surface ligands by 11-mercaptoundecanoic acid (11-MUA), which enhances protein affinity to the nanoparticles. According to SERS ( Figure 1E), for the samples before ligand exchange, the peaks associated with the pyrrolidone groups (856 cm -1 , ring breathing), methylene groups (CH 2 bending, 1400~1500 cm -1 ; CH 2 twisting, 1180-1300 cm -1 ; CH 2 rocking, 720-1150 cm -1 ), and carbonyl groups (carbonyl stretching, 1583 cm -1 ) [25,26], indicate that PVP polymer chains lay on the nanoparticle surface and are anchored via their carbonyl group, instead of dangling in solution [27]. On the other hand, the SERS of 11-MUA-capped AuNG has only three major peaks: at 713 cm -1 , representing the vibration mode 8 of the C-S bond in trans conformation; at 1100 cm -1 , associated with the vibration mode of the C-C backbone; and the relatively weaker peak doublet at 1401 cm -1 and 1431 cm -1 that is attributed to the overlapping of the vibration mode of COO -1 in free solution and the stretching mode of CH 2 , respectively [28].…”

Section: Nanoparticles and Surface Ligandsmentioning

confidence: 99%

Selective characterization of proteins on nanoscale concave surfaces

et al. 2016

View full text Add to dashboard Cite

Nanoscale curvature plays a critical role in nanostructure-biomolecule interactions, yet the understanding of such effects in concave nanostructures is still very limited. Because concave nanostructures usually possess convex surface curvatures as well, it is challenging to selectively study the proteins on concave surfaces alone. In this work, we have developed a novel and facile method to address this issue by desorbing proteins on the external surfaces of hollow gold nanocages (AuNG), allowing the selective characterization of retained proteins immobilized on their internal concave surfaces. The selective desorption of proteins was achieved via varying the solution ionic strength, and was demonstrated by both calculation and experimental comparison with non-hollow nanoparticles. This method has created a new platform for the discrete observation of proteins adsorbed inside AuNG hollow cores, and this work suggests an expanded biomedical application space for hollow nanomaterials.

show abstract

Surface resonance Raman and surface-enhanced Raman scattering excitation profiles for dabsyl aspartate on colloidal silver in ethanol

Cited by 14 publications

References 0 publications

SERS hyperspectral imaging assisted by MCR-ALS for studying polymeric microfilms loaded with paracetamol

SERS hyperspectral imaging assisted by MCR-ALS for studying polymeric microfilms loaded with paracetamol

Probing the Interaction of Poly(vinylpyrrolidone) with Platinum Nanocrystals by UV−Raman and FTIR

Selective characterization of proteins on nanoscale concave surfaces

Contact Info

Product

Resources

About