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The blood–brain barrier (BBB) is a main obstacle for drug delivery targeting the central nervous system (CNS) and treating Alzheimer's disease (AD). In order to enhance the efficiency of drug delivery without harming the BBB integrity, nanoparticle-mediated drug delivery has become a popular therapeutic strategy. Carbon dots (CDs) are one of the most promising and novel nanocarriers. In this study, amphiphilic yellow-emissive CDs (Y-CDs) were synthesized with an ultrasonication-mediated methodology using citric acid and o -phenylenediamine with a size of 3 nm that emit an excitation-independent yellow photoluminescence (PL). The content of primary amine and carboxyl groups on CDs was measured as 6.12 × 10 −5 and 8.13 × 10 −3 mmol mg −1 , respectively, indicating the potential for small-molecule drug loading through bioconjugation. Confocal image analyses revealed that Y-CDs crossed the BBB of 5-day old wild-type zebrafish, most probably by passive diffusion due to the amphiphilicity of Y-CDs. And the amphiphilicity and BBB penetration ability didn't change when Y-CDs were coated with different hydrophilic molecules. Furthermore, Y-CDs were observed to enter cells to inhibit the overexpression of human amyloid precursor protein (APP) and β-amyloid (Aβ) which is a major factor responsible for AD pathology. Therefore, data suggest that Y-CDs have a great potential as nontoxic nanocarriers for drug delivery towards the CNS as well as a promising inhibiting agent of Aβ-related pathology of the AD.
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This content will become publicly available on September 15, 2026
Synthesis of shape‐controlled silica nanoparticles via dual soft templates: A comparative study between aqueous and microemulsion synthesis for the impregnation of procaine anaesthesia drug
Abstract Silica nanoparticles (SiNPs) are promising drug delivery nanocarriers due to their tunable size, porous structure, and surface properties. This study compares two synthesis methods: (i) a low‐temperature aqueous sol–gel process yielding SiNPs of 500–700 nm, and (ii) a water‐in‐oil (W/O) microemulsion using either CTAB or TX‐100 surfactants. Surfactant selection significantly affected nanoparticle size, stability, and dispersity. Characterization by dynamic light scattering (DLS), scanning electron microscopy (SEM), X‐ray diffraction (XRD), Brunauer–Emmett–Teller (BET), solid‐state nuclear magnetic resonance spectroscopy (ssNMR), X‐ray photoelectron spectroscopy (XPS), and photoluminescence analysis (PL) confirmed successful synthesis. The TX‐100‐mediated microemulsion method proved particularly effective in achieving highly stable, reproducible, and monodisperse SiNPs, with a size limit of approximately 100 nm, making them ideal candidates for drug encapsulation. Procaine (PRC) incorporation demonstrated the role of reverse micelle dynamics and surfactant‐stabilized interfaces in enhancing encapsulation efficiency. This work highlights the critical role of surfactant and medium selection in SiNPs synthesis, demonstrating their impact on nanoparticle stability, dispersity, and drug loading efficiency. The TX‐100‐mediated microemulsion technique emerges as a superior approach for producing stable, monodisperse SiNPs, advancing the design of nanocarriers for PRC drug delivery applications.
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- Award ID(s):
- 2308660
- PAR ID:
- 10648566
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- The Canadian Journal of Chemical Engineering
- ISSN:
- 0008-4034
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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