Preparation and in-vitro characterization of tramadol-loaded carrier erythrocytes for long-term intravenous delivery

Abstract

The collective results of this study showed that the optimized method of entrapment was suitable for the encapsulation of tramadol in erythrocytes with the final carrier cells ready to enter the in-vivo animal studies as a promising long-circulating carrier for tramadol.

Biomembranes from slaughterhouse blood erythrocytes as prolonged release systems for dexamethasone sodium phosphate

“…It can also be seen that higher DexP efflux rate was obtained in case of samples with higher hemoglobin content (during the same experimental time) compared to samples with lower remained hemoglobin content and the effect of residual hemoglobin was more pronounced in case of bovine erythrocyte ghosts. This fact supports the theory that drug release is enhanced by hemoglobin release from erythrocyte carriers …”

“…The addition of GA aqueous solution (0.01% [v/ v]) in hypertonic stage of loading procedure showed slight effect on improvement of DexP loading parameters (26.5 vs. 34.5 ng/mL and 144.3 vs. 193.8 ng/mL for bovine and porcine erythrocyte ghosts without and with GA, respectively; P > 0.05). This was in contrast to the report of Foroozesh et al 37 in which GA (5 lL/100 mL) played a crucial role in improvement of drug (tramadol) loading parameters.…”

“…33 Also, the results demonstrated that the loading of DexP into both type of erythrocyte ghosts was directly proportional to the increase of drug concentration in the incubation medium, in the 0.04-0.12 mg/mL concentration range (Figures 2A,B). This finding is in agreement with the results reported by other research groups, [34][35][36][37] who employed hypoosmotic procedures to encapsulate various drugs in human erythrocyte ghosts. Figure 2C summarizes the effect of different DexP concentrations at 378C on drug encapsulation efficacy in bovine and porcine erythrocyte ghosts.…”

“…In general, kinetics of the drug release from erythrocyte carriers depends on the size and polarity of the encapsulated agents . Three different patterns of drug release are possible: (i) the drug release occurs by rapid diffusion through the membrane for lipophilic drugs such as primaquin or methotrexate; (ii) the drug release occurs by cell lysis, i.e., hemoglobin release for polar drugs such as enalaprilat, gentamicin, and tramadol; and (iii) the release profile is intermediate between the first two patterns, as observed for erythropoietin and isoniazid . Although erythrocyte ghosts represent product of controlled hemolysis of erythrocytes (i.e., the majority of hemoglobin content is removed), some residual hemoglobin is always present in resulting bovine and porcine erythrocyte ghosts .…”

Encapsulation of Valproate-Loaded Hydrogel Nanoparticles in Intact Human Erythrocytes: A Novel Nano-cell Composite for Drug Delivery

“…Several strategies have been attempted to overcome this problem with the use of membrane cross-linkers being the only successful one. [8][9][10][11][12] This strategy, however, suffers from the inclusion of foreign chemicals in the procedure, particularly, considering that these agents are potentially harmful to carrier cells life span in circulation via making their membranes more rigid compared with the normal cells. We, therefore, evaluated a novel strategy of using drug-loaded nanoparticles, instead of the "bare" drug for encapsulation in erythrocytes to solve the aforementioned problem.…”