Riboflavin (RF) is a water-soluble member of the B-vitamin family. Sufficient dietary and supplemental RF intake appears to have a protective effect on various medical conditions such as sepsis, ischemia etc., while it also contributes to the reduction in the risk of some forms of cancer in humans. These biological effects of RF have been widely studied for their anti-oxidant, anti-aging, anti-inflammatory, anti-nociceptive and anti-cancer properties. Moreover, the combination of RF and other compounds or drugs can have a wide variety of effects and protective properties, and diminish the toxic effect of drugs in several treatments. Research has been done in order to review the latest findings about the link between RF and different clinical aberrations. Since further studies have been published in this field, it is appropriate to consider a re-evaluation of the importance of RF in terms of its beneficial properties.

Hemoglobin-based oxygen carriers (HBOCs) represent a propitious type of blood substitute to transport oxygen throughout the body while acting as a carrier in biomedical applications. However, HBOCs in blood are recognized and rapidly scavenged by the body’s innate immune systems. To overcome this problem, HBOCs require a surface modification that provides protection against detection and elimination in order to prolong their circulation time after administration. In this study, we investigated different surface modifications of hemoglobin submicron particles (HbMPs) by double/triple precipitation, as well as by adsorption of human serum albumin (HSA), hyaluronic acid (HA), and pluronic (Plu) to discover how diverse surface modifications influence the oxygen binding capacity and the binding of anti-hemoglobin (Hb) antibodies, immunoglobulin G (IgG), and haptoglobin (HP) to HbMPs. The particle size and zeta potential of the six types of HbMP modifications were analyzed by zeta sizer, confocal laser scanning microscopy, and transmission electron microscopy (TEM), and were compared to the unmodified HbMPs. The results revealed that all surface-modified HbMPs had a submicron size with a negative charge. A slight decrease in the oxygen binding capacity was noticed. The specific binding of anti-Hb antibodies, IgG, and HP to all surface-modified HbMPs was reduced. This indicates a coating design able to protect the particles from detection and elimination processes by the immune system, and should lead to a delayed clearance and the required and essential increase in half-life in circulation of these particles in order to fulfill their purpose. Our surface modification method reflects a promising strategy for submicron particle design, and can lead the way toward novel biomedical applications.