Synthesis of Poly(N-vinylcaprolactam)-Grafted Magnetite Nanocomposites for Magnetic Hyperthermia

Morfin-Gutierrez, Adriana; Meléndez‐Ortiz, H. Iván; Puente-Urbina, Bertha; Garcı́a-Cerda, L.A.

doi:10.1155/2018/9562020

Cited by 5 publications

(2 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For pure SLP, the VA and VCL carbonyl bands shift to lower wavenumbers by 15 and 26 cm –1 , respectively, when the polymer is hydrated, which suggests less hydration of these units in comparison to hydrated CPV. Likewise, the VA ether band of SLP shifts from 1233 to 1253 cm –1 (overlapping with the C–N band at 1260 cm –1 ), due to effects of hydration . Interestingly, the ether band at 1085 cm –1 , associated with the PEG chains, which constitute only 13 wt % of SLP, becomes very conspicuous, indicating that the PEG chains enrich the polymer surface once in contact with water.…”

Section: Results and Discussionsupporting

confidence: 88%

“…Likewise, the VA ether band of SLP shifts from 1233 to 1253 cm −1 (overlapping with the C−N band at 1260 cm −1 ), due to effects of hydration. 53 Interestingly, the ether band at 1085 cm −1 , associated with the PEG chains, which constitute only 13 wt % of SLP, becomes very conspicuous, indicating that the PEG chains enrich the polymer surface once in contact with water. Overall, the observed hydration features and differences in the spectra of the wet CPV and SLP support the observed early-stage dissolution behavior of the polymers in the MD simulations (Figure 3).…”

Section: Resultsmentioning

confidence: 98%

See 1 more Smart Citation

Molecular-Level Examination of Amorphous Solid Dispersion Dissolution

et al. 2021

View full text Add to dashboard Cite

Amorphous solid dispersions (ASDs) are commonly used to orally deliver small-molecule drugs that are poorly water-soluble. ASDs consist of drug molecules in the amorphous form which are dispersed in a hydrophilic polymer matrix. Producing a high-performance ASD is critical for effective drug delivery and depends on many factors such as solubility of the drug in the matrix and the rate of drug release in aqueous medium (dissolution), which is linked to bioperformance. Often, researchers perform a large number of design iterations to achieve this objective. A detailed molecular-level understanding of the mechanisms behind ASD dissolution behavior would aid in the screening, designing, and optimization of ASD formulations and would minimize the need for testing a wide variety of prototype formulations. Molecular dynamics and related types of simulations, which model the collective behavior of molecules in condensed phase systems, can provide unique insights into these mechanisms. To study the effectiveness of these simulation techniques in ASD formulation dissolution, we carried out dissipative particle dynamics simulations, which are particularly an efficient form of molecular dynamics calculations. We studied two stages of the dissolution process: the early-stage of the dissolution process, which focuses on the dissolution at the ASD/water interface, and the late-stage of the dissolution process, where significant drug release would have occurred and there would be a mixture of drug and polymer molecules in a predominantly aqueous environment. Experimentally, we used Fourier transform infrared spectroscopy to study the interactions between drugs, polymers, and water in the dry and wet states and the chromatographic technique to study the rate of drug and polymer release. Both experiments and simulations provided evidence of polymer microstructures and drug−polymer interactions as important factors for the dissolution behavior of the investigated ASDs, consistent with previous work by Pudlas et al. (Eur. J. Pharm. Sci. 2015, 67, 21−31). As experimental and simulation results are consistent and complementary, it is clear that there is significant potential for combined experimental and computational research for a detailed understanding of ASD formulations and, hence, formulation optimization.

show abstract

Section: Results and Discussionsupporting

confidence: 88%

Section: Resultsmentioning

confidence: 98%