The physicochemical properties of drug nanocarriers such as layered double hydroxide nanoparticles (LDH-NPs) determine their circulation times in biological media and their interaction with the targeted cells. Nevertheless, the components of the biological fluid, and particularly the formation of a protein corona, change the properties of as-prepared nanocarriers. Here, we discuss the effect of the protein corona formation on the colloidal stability and reactivity of LDH-NPs intercalated with chloride (LDH–Cl), carbonate (LDH–CO₃) or dodecylsulfate (LDH–DS). These solids present model physicochemical properties (hydrophillic character, surface charge, and exchange capacity) that can be obtained depending on the interaction of drugs with LDH layers. The colloidal stability of LDH-NPs was determined in simulated biological fluids at high ionic strength and/or the presence of albumin (the main protein of human blood plasma), whereas the reactivity was evaluated by dissolution kinetics in acidic media, compatible with the environment of cell internalized nanocarriers. The protein corona increased the colloidal stability of the nanocarriers by steric hindrance at high ionic strength, reverted the positive zeta potential of as-prepared LDH-NPs and protected them from dissolution at low pHs. The properties of the anionic cargo of LDH-NPs strongly affected the protein corona and hence the fate of NPs in biological fluids. Drug nanocarriers with interfacial properties similar to those of LDH–Cl and LDH–CO₃ seem to be more promising than LDH–DS in forming a protein corona. Then, LDH–Cl and LDH–CO₃ would enable long circulation times due to their size, colloidal stability and low protein damage. Our results indicate that LDH-NPs preserve and even improve their properties as drug nanocarriers after interacting with the biological media, particularly their ability to reach the site of therapeutic action from the injection place.

Sexually-transmitted infections (STIs) are a global health concern worldwide as they cause acute diseases, infertility, and significant mortality. Among the bacterial, viral, and parasitic pathogens that can be sexually transmitted, human immunodeficiency virus (HIV) has caused one of the most important pandemic diseases, which is acquired immune deficiency syndrome (AIDS). 32.7 million people have died from AIDS-related illnesses since the start of the epidemic. Moreover, in 2019, 38 million people were living with HIV worldwide. The need to deal with this viral infection becomes more obvious, because it represents not only a problem for public health, but also a substantial economic problem. In this context, it is necessary to focus efforts on developing methods for prevention, detection and treatment of HIV infections that significantly reduce the number of newly infected people and provide a better quality of life for patients. For several decades, biomedical research has been developed allowing quick solutions through the contribution of effective tools. One of them is the use of polymers as vehicles, drug carrier agents, or as macromolecular prodrugs. Moreover, nanosystems (NSs) play an especially important role in the diagnosis, prevention, and therapy against HIV infection. The purpose of this work is to review recent research into diverse NSs as potential candidates for prevention and treatment of HIV infection. Firstly, this review highlights the advantages of using nanosized structures for these medical applications. Furthermore, we provide an overview of different types of NSs used for preventing or combating HIV infection. Then, we briefly evaluate the most recent developments associated with prevention and treatment alternatives. Additionally, the implications of using different NSs are also addressed.