| RESEARCH PAPER
|Year : 1998 | Volume
| Issue : 3 | Page : 199-202
Effect of size and charge of liposomes on biodistribution of encapsuled ggmTc-DTPA in rats
Nabar J Swapna, GD Nadkarni
0bjectives:To study the effect of size and charge of the liposome on the biodistribution of encapsulated 99m Tc-DTPA after intravenous injection into rats.
Methods: Multilamellar (MLV) and small unilamellar (SUV) vesicles were prepared, each having positive, negative and neutral charge. 99mTc-DTPA was encapsulated into each of these liposomes as a marker of aqueous phase. Radioactivity at 3, 30 and 60 minutes in blood, liver, spleen, lungs and kidneys was measured.
Results: MLVs were taken up to a greater extent as compared to SUVs in liver, spleen and lungs. Positively charged MLVs were taken up to a greater extent in liver as compared to neutral and negatively charged MLVs. In kidneys there was greater uptake of positively charged SUVs which was not significantly different from positively charged MLVs. Charge of MLV did not affect its uptake by kidney and spleen. Liposome encapsulated 99mTc-DTPA remained in circulation for a longer time as compared to free 99mTc-DTPA. Neutral MLVs were taken up to a greater extent by lungs at 1 h as compared to charged liposomes.
Conclusions: Positively charged MLVs could be used to target drugs to liver. Positively charged SUVs could be more effective to target drugs to kidneys. MLVs could be used to target drug to spleen irrespective of charge.
Nabar J Swapna
Source of Support: None, Conflict of Interest: None