生物医学成像和药物载体
案例
气相对 HFBII 在空气/水界面的吸附有何影响？
参考文献：Gazzera, L.; Milani, R.; Pirrie, L.; Schmutz, M.; Blanck, C.; Resnati, G.; Metrangolo, P.; Krafft, M. P., Design of highly stable echogenic microbubbles through controlled assembly of their hydrophobin shell. Angewandte Chemie 2016, 128 (35), 10419-10423.
Microbubbles are used as ultrasound contrast agents (UCAs) in biomedical imaging and need to be highly stable. Hydrophobins are a class of cysteine rich proteins used by the authors to stabilize µ-bubbles. Using an automatic drop tensiometer, TRACKER™ by TECLIS, the authors performed surface tension measurements that showed that F-hexane saturated-air resulted in a faster adsorption kinetics of hydrophobin HFBII and in a smaller equilibrium surface tension. Moreover, F-hexane decreased the viscoelastic modulus of the surface film. In summary, exposure to F-hexane enables the efficient, quasi-exclusive formation of homogenous, narrowly dispersed populations of spherical stable and echogenic µ-bubbles.
TECLIS 产品： TRACKER™ 界面流变仪
关键词： fluorinated gas, microbubbles, stability, surface tension, fluid-to-solid transition, 2D viscoelasticity.
如何通过添加表面活性剂来提高
蛋白质药物产品的稳定性？
参考文献：Katz, J. S.; Nolin, A.; Yezer, B. A.; Jordan, S., Dynamic properties of novel excipient suggest mechanism for improved performance in liquid stabilization of protein biologics. Molecular pharmaceutics 2018, 16 (1), 282-291.
Surfactants are commonly used to improve the stability of protein drug products; however, this stability is often insufficient. In this paper, the performance of FM1000, a surfactant containing an alkyl chain, an amino acid, and a polyether amine, is compared to Polysorbate 20, Polysorbate 80, and Poloxamer 188 in the presence of IgG and abatacept. First, surface tension measurements performed with an automatic drop tensiometer ( TRACKER™ by TECLIS) showed that FM1000 stabilizes an interface 1 to 2 orders of magnitude faster than the other probed surfactants. These results were confirmed by interfacial rheology experiments. These experimental data allowed to determine the surfactant diffusion to the interface using the Lucassen-van den Temple diffusion-exchange model. These results provide mechanistic understanding of the key causes and drivers of protein aggregation.
TECLIS 产品： TRACKER™ 界面流变仪+ 自动CMC测定选项
关键词： Surface tension, Interfacial dilatational rheology, protein-surfactant interactions, diffusion.
如何有效追踪荧光纳米载体？
参考文献：Bastiat, G.; Pritz, C. O.; Roider, C.; Fouchet, F.; Lignières, E.; Jesacher, A.; Glueckert, R.; Ritsch-Marte, M.; Schrott-Fischer, A.; Saulnier, P., A new tool to ensure the fluorescent dye labeling stability of nanocarriers: a real challenge for fluorescence imaging. Journal of controlled release 2013, 170 (3), 334-342.
Reading the interfacial activity gives information about the localization of molecules. When molecules reach the interface due to their amphiphilic properties, they lower the surface tension value. In this paper, adsorption kinetics were obtained at a Labrafac-water interface. Organic dyes (NR, 6-Cou, DiI and DiD) were dissolved in the oil phase prior to measurements. Dynamic surface tension experiments show that NR and 6-Cou do not change the interfacial tension whereas Dil and Dio lower the interfacial tension suggesting that DiI and DiD dyes behave as amphiphilic molecules and move from the oily core of the drop to the Labrafac-water interface. Furthermore, it was demonstrated that dyes like NR and 6-Cou could be transferred from the LNCs (lipid nano-capsules) to an oily medium or can enter blank LNCs from oily compartment. In addition, no transfer of indocarbocyanine dyes occurred. These two antagonistic properties can be explained by different dye localizations inside the nanocarrier. NR and 6-Cou localized in the core of the LNCs could be transferred in the presence of an external lipophilic compartment whereas DiI, DiO and DiD, trapped in the shell of the LNCs, could not be transferred, even in the presence of an external lipophilic compartment.
TECLIS 产品： TRACKER™ 界面流变仪
关键词： nanocarriers, migration, fluorescent dye, surface tension .
肽能与脂质纳米胶囊结合并加强其传递吗？
参考文献：Balzeau, J.; Pinier, M.; Berges, R.; Saulnier, P.; Benoit, J.-P.; Eyer, J., The effect of functionalizing lipid nanocapsules with NFL-TBS. 40-63 peptide on their uptake by glioblastoma cells. Biomaterials 2013, 34 (13), 3381-3389.
The aim of this study is to test whether a cell-penetrating peptide, NFL-TBS.40-63, can increase the targeted uptake by glioblastoma cells of lipid nano-capsules filled with Paclitaxel, and thus increase their anti-proliferation in vitro and in vivo. Surface tension measurements with an automatic drop tensiometer (TRACKER™ by TECLIS) at a Labrafac/water and Labrafac/water interface stabilized with Solutol were performed in a peptide range concentration from 0 to 14.10-5 mol/L. Results indicate that the peptide exhibits surfactant property at the oil/water interface but do not lower the surface tension in the presence of Solutol. Thus, this interfacial behavior suggests an interaction with the Solutol and not directly with Labrafac. All these results demonstrate that the NFLTBS.40-63 peptide is adsorbed at the surfactant layer. Further characterizations with complementary techniques demonstrated that the NFL-TBS.40-63 peptide exhibits the ability to enhance the delivery of lipid nano-capsules in mouse glioma cells and astrocytes.
TECLIS 产品： TRACKER™ 界面流变仪
关键词： drop tensiometry, surfactant-peptide interaction, drug delivery.
Eudragit RL100 稳定的 Pickering 纳米乳液
可以用作药物输送系统吗 ?
参考文献：Dieng, S. M., Omran, Z., Anton, N., Thioune, O., Djiboune, A. R., Sy, P. M., ... & Vandamme, T. (2020). Pickering nano-emulsions stabilized by Eudragit RL100 nanoparticles as oral drug delivery system for poorly soluble drugs. Colloids and Surfaces B: Biointerfaces, 191, 111010.
Pickering nano-emulsions are being investigated as drug delivery systems because they could offer many advantages: facilitate dermal drug delivery, increase the oral adsorption of poorly water-soluble drugs, etc. In this paper, the authors study Pickering nano-emulsions stabilized by Eudragit RL100 as drug delivery systems. Eudragit RL100 nano-particles (NPs) were chosen because they are stable towards the physiological conditions encountered in the gastro-intestinal tract and, as a model encapsulated drug, ketoprofen has been solubilized into the internal phase of the nano-emulsions. An important step of this study consisted in probing the interfacial properties of NPs in terms of surface tension and interfacial rheology using an automatic drop tensiometer (TRACKER™ by TECLIS). The experiments were performed at a C6H12 /aqueous NPs solution and showed that NPs adsorb at the interface and lower the interfacial tension. As for the interfacial rheology, the results showed that the oscillation frequency has an important impact on the conservative contribution E’. This interfacial behavior is very likely contributing to the observed stability of Eudragit RL100 stabilized Pickering nano-emulsions.
TECLIS 产品： TRACKER™ 界面流变仪
关键词： Pickering nano-emulsions, interfacial tension, interfacial rheology.
碳氟化合物气体能否用于产生
医疗应用的纳米金刚石涂层微泡？
参考文献：Mendoza-Ortega, E. E., Dubois, M., & Krafft, M. P. (2020). Fluorocarbon Gas Exposure Induces Disaggregation of Nanodiamond Clusters and Enhanced Adsorption, Enabling Medical Microbubble Formation. ACS Applied Nano Materials, 3(9), 8897-8905.
On the one hand, nano-diamonds (NDs) are intensively studied in biology and medicine for their potential application for sensing, bioimaging and drug delivery. However, their use is still limited due to their tendency to form aggregates. On the other hand, micro-bubbles (MBs), usually stabilized with a phospholipid shell, are used in medicine as ultrasound contrast agents. In this paper, the authors investigate the generation of MBs stabilized with a ND shell using fluorocarbon gas. Firstly, the disaggregating effect of fluorocarbon gases (F-hexane and F-pentane) on ND25 (25nm in diameter) and their fluorinated analogs F-ND25 in aqueous solutions has been demonstrated. Secondly, the adsorption of NDs at water-gas interfaces is characterized with surface tension measurements using an automatic drop tensiometer (TRACKER™ by TECLIS). These results showed that ND25 adsorbs slowly and only slightly at an air/aqueous solution interface while exposing ND25 to F-hexane results in a faster and much pronounced adsorption. Similar results are reported for F-ND25 which indicates a synergetic effect between F-hexane and NDs at the interface. Finally, the authors show that fluorocarbon gas enables the production of microbubbles shelled only with nano-diamonds, in the absence of any other surfactant, which could not be achieved without the fluorocarbon being present.
TECLIS 产品： TRACKER™ 界面流变仪
关键词： surface tension, nanoparticle, fluorocarbon gas, nano-diamond, micro-bubbles.