Solvent-Free Fabrication of Biphasic Lipid-Based Microparticles with Tunable Structure

Lipid-based biphasic microparticles are generally produced by long and complex techniques based on double emulsions. In this study, spray congealing was used as a solvent-free fabrication method with improved processability to transform water-in-oil non-aqueous emulsions into spherical solid lipid-based particles with a biphasic structure (b-MPs). Emulsions were prepared by melt emulsification using different compositions of lipids (Dynasan®118 and Compritol®888 ATO), surfactants (Cetylstearyl alcohol and Span®60) and hydrophilic carriers (PEGs, Gelucire®48/16 and Poloxamer 188). First, pseudo-ternary phase diagrams were constructed to identify the area corresponding to each emulsion type (coarse emulsion or microemulsion). The hydrophobicity of the lipid mostly affected the interfacial tension, and thus the microstructure of the emulsion. Emulsions were then processed by spray congealing and the obtained b-MPs were characterized in terms of thermal and chemical properties (by DSC and FT-IR), external and internal morphology (by SEM, CLSM and Raman mapping). Solid free-flowing spherical particles (main size range 200–355 µm) with different architectures were successfully produced: microemulsions led to the formation of particles with a homogeneous internal structure, while coarse emulsions generated “multicores-shell” particles consisting of variable size hydrophilic cores evenly distributed within the crystalline lipid phase. Depending on their composition and structure, b-MPs could achieve various release profiles, representing a more versatile system than microparticles based on a single lipid phase. The formulation and technological strategy proposed, provides a feasible and cost-effective way of fabricating b-MPs with tunable internal structure and release behavior.

Recent Progress of Novel Electrochemiluminescence Nanoprobes and Their Analytical Applications

High-performance nanomaterials have been seen as a new generation of electrochemiluminescence (ECL) probes or emitters for their finely tunable structure and concomitant remarkable properties, guaranteeing the prospective applications in the analysis and diagnosis devices with superior performances. The structure–activity relationships of ECL nanoprobes in nanoscale are presenting milestone in understanding of the ECL microscopic behaviors and mechanisms, and guide the exploitation of novel ECL probes. In this mini-review, we summarized the recent development of novel ECL probes based on the nanomaterials. The mechanism and relationships between their structure as well as the active sites and functionality were revealed. In addition, the design and regulation of the ECL nanoprobes were emphasized for the biosensing and imaging application. Finally, the potential prospect of the ECL nanoprobes, design, and their applications were discussed.

Room-temperature growth of covalent organic framework as stationary phase for open-tubular capillary electrochromatography

Covalent organic frameworks (COFs) is a class of porous materials with high surface area, high porosity, good stability and tunable structure that have been neatly used in the separation area....

Self-assembly of Cuprous Iodide Cluster-based Calix[4]resorcinarenes and Photocatalysis Properties

The controlling self-assembly of cuprous iodide cluster-based supramolecular architectures with tunable structure is still a big challenge up to date. We adopt conformation-adaptive self-assembly strategy to precisely construct two [CumIn]...

A Facile Synthesis of HKUST-1 MOF through Reductive Electrosynthesis Method

Metal-organic frameworks (MOFs) are porous crystalline materials that consist of metal ions bind to organic ligands as linkers by coordination covalent bonds. MOF properties, such as the presence of open metal sites, large surface area, high porosity, high thermal stability, tunable structure, and feasibility in modification are controlled and determined by metal cations, organic linkers, and applied synthetic method. Reductive electrosynthesis is a popular and interesting MOF synthetic method on the surface of conductive substrates. This method is based on electroreduction of oxoanions to generate hydroxide anions that lead to selective deposition of MOFs on conductive surfaces to form a thin MOFs film. The applied potentials during electrosynthesis affect the properties and applications of the produced MOFs. Here, Cu-based MOFs with the type of CuBTC (H3BTC: 1,3,5-benzenetricarboxylic acid) known as HKUST-1 films were synthesized using different cathodic potentials and time, at room temperature, on the surface of brass. The reductive electrosynthesis was found to be fast and mild for preparing HKUST-1. This method allows direct surface modification which in turn affect the HKUST-1 applications as electrode material for electrochemical sensing such as glucose.