A Green pH‐switchable Amino Acid Based Smart Wormlike Micellar System for Efficient and Controlled Drug Delivery

Abstract

A biocompatible and biodegradable amino‐acid based anionic surfactant system has been formulated which self assembles into wormlike micelles in presence of NaCl and displays excellent sol‐gel transition under pH stimulus. The surfactant synthesized was Sodiumtetradecanoyl Phenyl Alanine (STDPA). The micellar solution behaves as sol at /below pH 8.25 and transforms into gel at /above pH 8.65, exhibiting sol‐gel transition in a very narrow pH range. This pH triggered sol‐gel transition shows excellent reversibility upon recurrent changes in pH. Steady and dynamic rheological experiments reveal that the solution at/above pH 8.65 is viscoelastic due to the formation of wormlike micelles (WLMs) and was Newtonian at/below 8.25 due to the presence of spherical micelles. The microstructural evolution was further validated by Dynamic Light Scattering and Cryo TEM imaging. Further, the formulation was used to study the release of drug Ibuprofen (IBU) at these two pHs. IBU release from the material depends on pH of the release medium and occurs without any burst release at pH 8.65.

Temperature- and Composition-Induced Multiarchitectural Transitions in the Catanionic System of a Conventional Surfactant and a Surface-Active Ionic Liquid

“…With the increase in temperature to 60 °C, the flow behavior changes significantly, exhibiting an increase in the low shear viscosity and the slight appearance of the viscosity plateau, which is indicative of the presence of entangled structures of rodlike micelles. Although the plateau is not prominent in this solution which is probably due to the difference in the mole fraction of two components, eventually leading to the disparate behavior in the low shear rates, due to their comparatively large size, rodlike micelles exhibit a slight resistance in their flow behavior when they are sheared slightly at low shear rates, 34 thereby exhibiting a viscosity plateau in their flow curves. On the other hand, the flow curves in the case of X CTAB = 0.55 ( Figure 4 b) describe two different types of transitions, which are in complete agreement with the microstructural transitions inferred from the turbidity and dynamic rheological measurements.…”

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

“…Although there are several examples of studies dealing with the synthesis of this kind of compounds [ 25 ], the majority of investigations are dedicated to discussion of their physicochemical properties in solutions and potential applications in biomedicine. For example, hydrophobized phenylalanine and valine derivatives demonstrated high cytotoxicity against the MCF-7 and HEK cell lines [ 26 ], pH-dependent self-assembly behavior [ 27 ] and could be used for construction of worm-like aggregates for ibuprofen delivery [ 28 ]. As a separate line of investigation, the interaction of these amphiphiles with biological species should be mentioned: glycine and sarcosinate derivatives are approved as effective agents for complexation with carrageenans of various types [ 29 ] and myoglobin [ 30 ].…”

Effect of the Substituent Position on the Phase Behavior and Photoresponsive Dynamic Behavior of Mixed Systems of a Gemini Surfactant and trans-Methoxy Sodium Cinnamates

“…Wormlike micelles are composed of long and flexible surfactant aggregates, which are easily entangled into a dynamic reversible network structure and exhibit unique viscoelastic rheological behaviors. Viscoelastic wormlike micelles with adjustable rheological properties in response to light or pH stimulation have potential applications in many fields such as drag-reducing fluids, , microflow sensors, rheology control, drug release, and so on.…”