Conjugates of Gold Nanoparticles and Antitumor Gold(III) Complexes as a Tool for Their AFM and SERS Detection in Biological Tissue
Abstract
:1. Introduction
2. Results
2.1. Prediction of Gold(III) Complexes Binding to Citrate-Capped AuNPs
2.2. Spectrophotometric Study of the Interaction Between Gold(III) Complexes and AuNPs
2.3. AFM Images of AuNPs /Au(III) Complexes Assembly
2.4. SERS Spectra of Au(III) Complexes
2.5. AFM and SERS Tracking of Gold(III) Complexes in the Cytosolic, Nuclear, and Plasma Membrane Fractions of Human Lymphocytes
3. Discussion
4. Materials and Methods
4.1. Chemicals
4.2. Synthesis of AuNPs
4.3. Subcellular Fractionation of Human Lymphocytes
4.4. Apparatus
4.5. DFT Calculations
5. Conclusions
Supplementary Materials
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
Abbreviations
(C:N) | deprotonated 6-(1,1-dimethylbenzyl)-pyridine |
(C,N,N) | deprotonated 6-(1,1-dimethylbenzyl)-2,2′-bipyridine |
(N,N) | 2,2′-bipyridine |
PBS | Phosphate buffer solution |
HEPES | 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid |
DFT | Density functional theory |
CLS | Compact laser system |
AFM | Atomic Force Microscopy |
SERS | Surface-enhanced Raman spectroscopy |
LSPR | Localized surface Plasmon resonance |
NPs | Nanoparticles |
AuNPs | Gold nanoparticles |
AgNPs | Silver nanoparticles |
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Complex + Surface | Closest Complex-Surface Distance (Å) | Eads (eV) | Charge Received by Complex Molecule (e) | Optimized Binding Geometry |
---|---|---|---|---|
[Au(N,N)(OH)2]+ + Au111 (parallel) | 3.27 | −6.09 | −0.118 | |
[Au(N,N)(OH)2]+ + Au111 (vertical) | 2.55 | −4.07 | −0.097 | |
[Au(N,N)(OH)2]+Cl + Au111 | 3.88 | −0.43 | −0.231 | |
[Au(C,N)(AcO)2] + Au111 | 2.83 | −0.36 | −0.012 | |
[Au(C,N,N)(OH)]+ + Au111 | 2.13 | −4.48 | −0.110 |
Complex | Assignment a | Raman Vibrational Mode a (cm−1) | SERS Vibrational Mode (cm−1) | Membrane Fraction (cm−1) | Nuclear Fraction (cm−1) |
---|---|---|---|---|---|
[Au(C,N,N)(OH)] [PF6] | Au–N stretching | 324 | 316 | 321 | 321 |
602 | 602 | 610 | − | ||
In-plane ring deformation | 741 | 756 | − | 778 | |
C–H ring breathing | 1049 | 1031 | 1040 | 1043 | |
Aromatic C–C stretching | 1327 | 1315 | 1319 | 1319 | |
1496 | 1484 | 1486 | 1487 | ||
1575 | 1559 | 1568 | 1568 | ||
1603 | 1592 | 1591 | 1601 | ||
[Au(C,N)(AcO)2] | Au–N stretching | 317 | 319 | ||
− | 361 | ||||
− | 460 | ||||
523 | 549 | ||||
660 | 652 | ||||
In-plane ring deformation | − | 758 | |||
C–H ring breathing | 1046 | 1037 | |||
1272 | 1270 | ||||
Aromatic C–C stretching | − | 1592 | |||
1616 | |||||
[Au(N,N)(OH)2] [PF6] | Au–N stretching | 342 | 357 | 342 | |
475 | 421 | 482 | |||
725 | − | − | |||
Ring deformation in the plane | 757 | 757 | 707 | ||
882 | 1006 | 996 | |||
− | 1021 | 1026 | |||
C–H ring breathing | 1051 | 1055 | 1168 | ||
1326 | 1308 | 1315 | |||
1504 | 1484 | 1443 | |||
Aromatic C–C stretching | 1572 | 1559 | 1547 | ||
1609 | 1592 | 1608 | |||
2,2′-bipyridine b | Out-of-plane ring deformation | 328 | 354 | ||
548 | − | ||||
611 | 646 | ||||
In-plane ring deformation | 752 | 761 | |||
992 | 1010 | ||||
1043 | 1057 | ||||
C–H ring breathing | 1298 | 1301 | |||
1480 | 1479 | ||||
1570 | 1562 | ||||
Aromatic C–C stretching | 1588 | 1586 | |||
Pyridine b | Out-of-plane ring deformation | 389 | |||
385 | |||||
In-plane ring deformation | 618 | 636 | |||
C–H ring breathing | 1002 | 1009 | |||
1036 | 1035 | ||||
1220 | 1213 | ||||
Aromatic C–C stretching | 1583 | 1597 | |||
- | 1639 |
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Bondžić, A.M.; Leskovac, A.R.; Petrović, S.Ž.; Vasić Anićijević, D.D.; Luce, M.; Massai, L.; Generosi, A.; Paci, B.; Cricenti, A.; Messori, L.; et al. Conjugates of Gold Nanoparticles and Antitumor Gold(III) Complexes as a Tool for Their AFM and SERS Detection in Biological Tissue. Int. J. Mol. Sci. 2019, 20, 6306. https://doi.org/10.3390/ijms20246306
Bondžić AM, Leskovac AR, Petrović SŽ, Vasić Anićijević DD, Luce M, Massai L, Generosi A, Paci B, Cricenti A, Messori L, et al. Conjugates of Gold Nanoparticles and Antitumor Gold(III) Complexes as a Tool for Their AFM and SERS Detection in Biological Tissue. International Journal of Molecular Sciences. 2019; 20(24):6306. https://doi.org/10.3390/ijms20246306
Chicago/Turabian StyleBondžić, Aleksandra M., Andreja R. Leskovac, Sandra Ž. Petrović, Dragana D. Vasić Anićijević, Marco Luce, Lara Massai, Amanda Generosi, Barbara Paci, Antonio Cricenti, Luigi Messori, and et al. 2019. "Conjugates of Gold Nanoparticles and Antitumor Gold(III) Complexes as a Tool for Their AFM and SERS Detection in Biological Tissue" International Journal of Molecular Sciences 20, no. 24: 6306. https://doi.org/10.3390/ijms20246306