Lubrication and Dynamically Controlled Drug Release Properties of Tween 85/Tween 80/H₂O Lamellar Liquid Crystals

Abstract

Lamellar liquid crystals have amazing lubricating and drug-solubilizing properties. Hence, the combination of drug molecules with lamellar liquid crystals is expected to be used in joint lubrication and treatment. In this study, the partial phase diagram of the Tween 85/Tween 80/H2O three-component system was determined. The phase structure of the system changed from a hexagonal liquid crystal to a lamellar liquid crystal with the increase of Tween 85 content. The lamellar liquid crystals showed superior lubricating properties due to their unique lamellar structure. Furthermore, the model of drug release during friction was established for the first time. It was found that the order of the lamellar liquid crystals increased with the increase of the mass ratio of Tween 85/Tween 80, leading to the decrease of the ibuprofen release rate. In addition, the release rate of ibuprofen increased progressively with the increase of the friction frequency, but the load had little effect on it. Therefore, the lamellar liquid crystals consisting of nonionic surfactants with good biocompatibility have potential application prospects for joint lubrication and treatment of arthritis.

Construction and Properties of O/W Liquid Crystal Nanoemulsion

“…Three obvious Bragg diffraction peaks could be distinctly observed at q 1 = 0.115 Å –1 , q 2 = 0.231 Å –1 , and q 3 = 0.347 Å –1 for both the prepared liquid crystal emulsion and the nanoemulsion. The corresponding scattering vector ( q ) value ratio of these Bragg diffraction peaks followed the relationship of 1/2/3, which proved the existence of lamellar liquid crystal structure. , It was reconfirmed that the obtained nanoemulsion was a liquid crystal emulsion. Furthermore, the lattice parameter d of the liquid crystal structure was 5.46 nm according to Bragg’s equation ( d = 2 π/q , where q is the scattering vector of the first scattering peak in each unit), which meant that the thickness of the bilayer should be 5.46 nm for the liquid crystal emulsion and the liquid crystal nanoemulsion.…”

In situ preparation of hydroxyapatite in lamellar liquid crystals for joint lubrication and drug delivery

“…51,52 The concentration of ibuprofen had an excellent linear relationship with the absorbance at 222 nm, and the standard curve was done in previous work. 45 When 0–50 mg of ibuprofen were solubilized per gram in the HAP/LLCs (H-3, Tween 85 : Tween 80 : H 2 O = 0.56 : 0.14 : 0.3), as shown in Fig. S3 (ESI†), a gradual change in polarization texture happened.…”

“…According to our previous studies, LLCs have good lubricating properties attributable to their ability to adsorb onto the surface of the friction substrate to form a lubricating film. 45,46 At low content (H-1 to H-3), HAP was able to fill in the recesses of impaired wear marks, improving the wear resistance of the friction surface to a certain extent and facilitating lubrication. As the content of HAP continued to increase (H-4), the excessive nanoparticles would increase the roughness of the friction surface and scratch the surface of the friction substrate, leading to a decrease in lubrication performance and more significant fluctuations in the coefficient of friction.…”

“…In addition, the LLCs can act as a vehicle to dissolve drugs and constantly release drugs. [15][16][17] So, LLCs have the potential to be developed as injectable synovial fluid additives to relieve the pain of osteoarthritis. However, the lubricating performance and bearing capacity of pure LLCs limited their application in the treatment of osteoarthritis.…”