This work demonstrated kinetically controlled release of model drugs (ibuprofen, FITC) from well-tailored mesoporous silica nanoparticles (MSNs) depending on the surface charges and molecular sizes of the drugs. The molecular interactions between entrapped drugs and the pore walls of MSNs controlled the release of the drugs through the pore channels of MSNs. Also, polydopamine (PDA) layer-coated MSNs (MSNs@PDA) was quite effective to retard the release of large FITC, in contrast to a slight retardation effect on relatively small Ibuprofen. Of all things, FITC (Fluorescein isothiocyanate)-labeled APTMS (3-aminopropyltrimethoxysilane) (APTMS-FITC conjugates) grafted onto the MSNs generate a pinch-effect on the pore channel (so-called a prominent anchoring effect), which was highly effective in trapping (or blocking) drug molecules at the pore mouth of the MSNs. The anchored APTMS-FITC conjugates provided not only tortuous pathways to the diffusing molecules, but also sustained release of the ibuprofen over a long period of time (∼7days). The fast release kinetics was predicted by an exponential equation based on Fick's law, while the slow release kinetics was predicted by Higuchi model.
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http://dx.doi.org/10.1016/j.jcis.2017.09.072 | DOI Listing |
Nano Lett
January 2025
School of Environment, Tsinghua University, Beijing 100084, China.
Exploiting cost-effective hydrogen evolution reaction (HER) catalysts is crucial for sustainable hydrogen production. However, currently reported nanocatalysts usually cannot simultaneously sustain high catalytic activity and long-term durability. Here, we report the efficient synthesis and activity tailoring of a chainmail catalyst, isolated platinum atom anchored tungsten carbide nanocrystals encapsulated inside carbon nanotubes (Pt/WC@CNTs), by confined flash Joule heating technique.
View Article and Find Full Text PDFJ Chem Phys
December 2024
Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.
We present a mechanistic study of pH-sensitive photoluminescence (PL) in two deliberately designed systems of carbon dots (CDs), which are relatively poor and rich in carboxyl groups anchored on their surfaces, denoted CDs-COOH(p) and CDs-COOH(r), respectively. The underlying PL mechanisms for the two contrasting CD systems are revealed to be different. As for CDs-COOH(p), the pH response of PL exhibits an asymmetric volcano-shaped pattern featuring dynamic and static quenching under acidic and alkaline conditions, dominated by the effects of hydrogen bonding and non-emissive ground-state complex, respectively.
View Article and Find Full Text PDFPeerJ Comput Sci
November 2024
School of Information and Communications Technology, Shenzhen City Polytechnic, Shenzhen, Gangdong, China.
ACS Appl Mater Interfaces
December 2024
Guangdong Provincial Key Laboratory of Optical Information Materials and Technology and Institute of Electronic Paper Displays South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, P. R. China.
Integrating microscale liquid crystal polymer flakes into host materials takes advantage of their compact shape and heightened responsiveness to electric fields, facilitating a range of switching capabilities and related applications, such as smart windows and E-paper displays. However, the complex physics controlling the movement of these flakes within liquid crystal hosts remains partly mysterious. This paper aims to elucidate the underlying physics that governs the behavior of nematic liquid crystal polymer flakes within nematic liquid crystal hosts.
View Article and Find Full Text PDFBiosensors (Basel)
November 2024
Biochemistry and Molecular Biology Unit, Department of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, Campus "Aurelio Saliceti" Via Renato Balzarini n. 1, 64100 Teramo, Italy.
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