Novel Hydrogel-Advanced Modified Clay Nanocomposites as Possible Vehicles for Drug Delivery and Controlled Release
Abstract
:1. Introduction
2. Results
2.1. Hydrogel Nanocomposites Characterization
2.1.1. Swelling/De-Swelling Properties
2.1.2. FTIR Spectroscopy
- -
- shifted wavenumbers values around 294 cm−1 due to CH2 stretching from PMAA and quaternary ammonium salts from clays;
- -
- shifted wavenumber values of C=O group (1736 cm−1) originated from PMAA toward lower values (Cl 93A—1733 cm−1; Cl 93A-C8—1723 cm−1; Cl 93A-C18—1707 cm−1);
- -
- the peak of Cl 93A clay from 1007 cm−1 corresponding to Si–O stretching vibration, shifted toward higher values with the inclusion of clay in the PMAA matrix (1036 cm−1);
- -
- clay peaks observed at 516 cm−1 and 441 cm−1 (Si–O–Si and Al–O–Si deformation) appeared in the nanocomposites FTIR spectra at higher values 518 cm−1 and 464 cm−1.
2.1.3. X-ray Diffractograms
2.1.4. Thermo-Mechanical Characteristics
2.1.5. Microscopy Analyses
2.2. Cell Proliferation Assay
2.2.1. Cytotoxicity
2.2.2. Cell Morphology
3. Experimental Section
3.1. Materials
3.2. The Synthesis of Composite Hydrogels
3.3. Hydrogel Nanocomposites Characterization
3.3.1. Physical-Chemical Characterization
3.3.2. In Vitro Cell Assay
4. Conclusions
Acknowledgments
Author Contributions
Conflicts of Interest
References
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Sample | 2 Theta (Å) | d-Spacing (nm) | ||
---|---|---|---|---|
(001) | (002) | (001) | (002) | |
Cl 93A | 3.28 | 6.55 | 26.88 | 13.48 |
PMAA | - | - | - | - |
PMAA-Cl 93A | 2.99 | 6.39 | 29.48 | 13.83 |
PMAA-Cl 93A-C8 | 3.12 | 6.40 | 28.22 | 13.80 |
PMAA-Cl 93A-C18 | 2.99 | 6.43 | 29.50 | 13.74 |
Sample | TGA/DTG | DMA | ||||||
---|---|---|---|---|---|---|---|---|
Weight Loss Intervals (%) | Decomposition Temperatures (°C) | Residue 700 °C (%) | Tg1 (°C) | Tg2 (°C) | ||||
0–120 °C | 120 °C–300 °C | 300 °C–700 °C | T1 | T2 | ||||
A | 8.28 | 10.63 | 71.43 | 230 | 420 | 9.59 | 85.15 | 226.30 |
B | 6.46 | 10.88 | 70.88 | 229 | 421 | 11.43 | 96.52 | 227.46 |
C | 6.96 | 10.30 | 71.26 | 231 | 380/419 | 11.48 | 94.36 | 233.27 |
D | 6.71 | 10.10 | 70.47 | 230 | 381/410 | 12.73 | 110.81 | 231.56 |
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Ianchis, R.; Ninciuleanu, C.M.; Gifu, I.C.; Alexandrescu, E.; Somoghi, R.; Gabor, A.R.; Preda, S.; Nistor, C.L.; Nitu, S.; Petcu, C.; et al. Novel Hydrogel-Advanced Modified Clay Nanocomposites as Possible Vehicles for Drug Delivery and Controlled Release. Nanomaterials 2017, 7, 443. https://doi.org/10.3390/nano7120443
Ianchis R, Ninciuleanu CM, Gifu IC, Alexandrescu E, Somoghi R, Gabor AR, Preda S, Nistor CL, Nitu S, Petcu C, et al. Novel Hydrogel-Advanced Modified Clay Nanocomposites as Possible Vehicles for Drug Delivery and Controlled Release. Nanomaterials. 2017; 7(12):443. https://doi.org/10.3390/nano7120443
Chicago/Turabian StyleIanchis, Raluca, Claudia M. Ninciuleanu, Ioana C. Gifu, Elvira Alexandrescu, Raluca Somoghi, Augusta R. Gabor, Silviu Preda, Cristina L. Nistor, Sabina Nitu, Cristian Petcu, and et al. 2017. "Novel Hydrogel-Advanced Modified Clay Nanocomposites as Possible Vehicles for Drug Delivery and Controlled Release" Nanomaterials 7, no. 12: 443. https://doi.org/10.3390/nano7120443