Tissue penetrability of nanoprticles loaded with Rhodamine B fluorescent marker using a trimodal administration approach

Nanoparticles can incorporate a drug, as means of protection towards body physiological barriers, and release it in a controlled manner in a targeted tissue.This study aims to investigate the absorption of nanoparticles, loaded with Rhodamine B fluorescent marker, in different organs, by trimodal administration: endogastric, intraperitoneal and intravenous, for three days.Materials and methods: The extent of absorption of Rhodamine B dye in liver, gums, kidneys, ovaries and testes was determined using fluorescence microscopy in frozen sections on harvested organs from rats.The experiment required 24 adult male rats that were divided into four groups of six rats each.Group A was designated as the control group, while the other three groups, B, C and D, respectively, received Rhodamine -loaded nanoparticles for three consecutive days, at a dose of 0.05 mg/kg body weight.The methods of administration for the three study groups were as follows: endogastric for group B, intr aperitoneal for group C, and injection into the tail vein for group D. On the fourth day the a nimals were sacrificed, and organs were removed and preserved in paraformaldehyde containers, to be studied under an immunofluorescence microscope.A four-level scale was used to evaluate organ penetrability for the given nanosystems.Results: Intraperitoneally administrated nanocarriers, marked with Rhodamine B, showed the highest degree of absorption in liver in 83.3% of the rats, compared to the endogastric route, where the same level of a bsorption was in only 33.3% of the animals (p=0.050).Regarding the two parenteral tested pathways, the absorption level presented statistical differences among the intraperitoneal vs. intravenous groups, in gum (p=0.011),heart (p=0.004),kidney (p=0.050) and testicle (p=0.011),whereas there was no statistical difference in liver tissue (p=0.250).Conclusions: The parenteral routes of administration had statistically significant higher organ penetrabi lity, compared to the endogastric tube.Amongst the organs, liver had the most absorptive b ehavior due to its intrinsic metabolizing role, and there was no major difference between the intraperitoneal vs. intravenous injections.