Architectures and Mechanical Properties of Drugs and Complexes of Surface-Active Compounds at Air-Water and Oil-Water Interfaces

摘要

Background: Drugs can represent a multitude of compounds from proteins and peptides,such as growth hormones and insulin and on to simple organic molecules such as flurbiprofen,ibuprofen and lidocaine. Given the chemical nature of these compounds two features are alwayspresent. A portion or portions of the molecule that has little affinity for apolar surfaces and mediaand on the contrary a series of part or one large part that has considerable affinity for hydrophilic,polar or charged media and surfaces. A series of techniques are routinely used to probe themolecular interactions that can arise between components, such as the drug, a range of surface–active excipients and flavor compounds, for example terpenoids and the solvent or dispersionmedium.Results: Fifty-eight papers were included in the review, a large number (16) being of theoretical natureand an equally large number (14) directly pertaining to medicine and pharmacy; alongside experimentaldata and phenomenological modelling. The review therefore simultaneously represents an amalgam ofreview article and research paper with routinely used or established (10) and well-reportedmethodologies (also included in the citations within the review). Experimental data included fromvarious sources as diverse as foam micro-conductivity, interferometric measurements of surfaceadsorbates and laser fluorescence spectroscopy (FRAP) are used to indicate the complexity and utilityof foams and surface soft matter structures for a range of purposes but specifically, here forencapsulation and incorporation of therapeutics actives (pharmaceutical molecules, vaccines andexcipients used in medicaments). Techniques such as interfacial tensiometry, interfacial rheology(viscosity, elasticity and visco-elasticity) and nanoparticle particle size (hydrodynamic diameter) andcharge measurements (zeta potential), in addition to atomic force and scanning electron microscopyhave proven to be very useful in understanding how such elemental components combine, link orreplace one another (competitive displacement). They have also proven to be both beneficial andworthwhile in the sense of quantifying the unseen actions and interplay of adsorbed molecules and themacroscopic effects, such as froth formation, creaming or sedimentation that can occur as a result ofthese interactions.Conclusion: The disclosures and evaluations presented in this review confirm the importance of atheoretical understanding of a complex model of the molecular interactions, network and present aframework for the understanding of really very complex physical forms. Future therapeuticdevelopers rely on an understanding of such complexity to garner a route to a more successfuladministration and formulation of a new generation of therapeutic delivery systems for use inmedicine.