Novel Sugar-Based Gemini Surfactants and Their Surface Properties

Gemini and Bicephalous Surfactants: A Review on Their Synthesis, Micelle Formation, and Uses

The use of surfactants in polymerization reactions is particularly important, mainly in emulsion polymerizations. Further, micelles from biocompatible surfactants find use in pharmaceutical dosage forms. This paper reviews recent developments in the synthesis of novel gemini and bicephalous surfactants, micelle formation, and their applications in polymer and nanoparticle synthesis, oil recovery, catalysis, corrosion, protein binding, and biomedical area, particularly in drug delivery.

Synthesis and Aggregation of Novel Sugar-based Gemini Surfactants in Aqueous Solution

Novel sugar-based gemini surfactants with a 1,3-propan-2-ol spacer (1, 3-(N- alkyl-2-D-glucosaminyl acetyl) propan-2-ol, Glu(n)-3(OH)-Glu(n), n = 12, 14) were synthesized with D-(+)-glucono-1,5-lactone as starting material in two steps, whose structures were confirmed using proton nuclear magnetic resonance spectroscopy (1H NMR) and carbon nuclear magnetic resonance carbon spectroscopy (13C NMR). The micellization of Glu(n)-3(OH)-Glu(n) (n = 12, 14) in aqueous solution at 25.0°C was investigated by using surface tension measurement. The results show that the critical micelle concentration (CMC) of Glu(12)-3(OH)-Glu(12) is around 10–5 mol × L–1, and is one order of magnitude smaller than that of Glu(14)-3(OH)-Glu(14), indicating that the surface activity of Glu(12)-3(OH)-Glu(12) is superior to that of Glu(14)-3(OH)-Glu(14). Moreover, the aggregation behavior of Glu(12)-3(OH)-Glu(12) in aqueous solution at different pH values was investigated by surface tension, dynamic light scattering (DLS), and cryogenic transmission electron microscopic (Cryo-TEM) measurements. The results indicate that the CMC slightly increases with the decrease of the solution pH. The microstructure of Glu(12)-3(OH)-Glu(12) aggregates transitions from micelle to vesicle with the solution pH from acidic to neutral and alkaline. The microstructural transformation of Glu(12)-3(OH)-Glu(12) with the solution pH is mainly determined by the protonation of the two tertiary amine nitrogen atoms in its hydrophilic headgroups.

A Review on Recent Progress of Glycan-Based Surfactant Micelles as Nanoreactor Systems for Chemical Synthesis Applications

The nanoreactor concept and its application as a modality to carry out chemical reactions in confined and compartmentalized structures continues to receive increasing attention. Micelle-based nanoreactors derived from various classes of surfactant demonstrate outstanding potential for chemical synthesis. Polysaccharide (glycan-based) surfactants are an emerging class of biodegradable, non-toxic, and sustainable alternatives over conventional surfactant systems. The unique structure of glycan-based surfactants and their micellar structures provide a nanoenvironment that differs from that of the bulk solution, and supported by chemical reactions with uniquely different reaction rates and mechanisms. In this review, the aggregation of glycan-based surfactants to afford micelles and their utility for the synthesis of selected classes of reactions by the nanoreactor technique is discussed. Glycan-based surfactants are ecofriendly and promising surfactants over conventional synthetic analogues. This contribution aims to highlight recent developments in the field of glycan-based surfactants that are relevant to nanoreactors, along with future opportunities for research. In turn, coverage of research for glycan-based surfactants in nanoreactor assemblies with tailored volume and functionality is anticipated to motivate advanced research for the synthesis of diverse chemical species.

Self-Assembly of Amphiphilic Compounds as a Versatile Tool for Construction of Nanoscale Drug Carriers

This review focuses on synthetic and natural amphiphilic systems prepared from straight-chain and macrocyclic compounds capable of self-assembly with the formation of nanoscale aggregates of different morphology and their application as drug carriers. Since numerous biological species (lipid membrane, bacterial cell wall, mucous membrane, corneal epithelium, biopolymers, e.g., proteins, nucleic acids) bear negatively charged fragments, much attention is paid to cationic carriers providing high affinity for encapsulated drugs to targeted cells. First part of the review is devoted to self-assembling and functional properties of surfactant systems, with special attention focusing on cationic amphiphiles, including those bearing natural or cleavable fragments. Further, lipid formulations, especially liposomes, are discussed in terms of their fabrication and application for intracellular drug delivery. This section highlights several features of these carriers, including noncovalent modification of lipid formulations by cationic surfactants, pH-responsive properties, endosomal escape, etc. Third part of the review deals with nanocarriers based on macrocyclic compounds, with such important characteristics as mucoadhesive properties emphasized. In this section, different combinations of cyclodextrin platform conjugated with polymers is considered as drug delivery systems with synergetic effect that improves solubility, targeting and biocompatibility of formulations.