Investigations on feasibility of in situ development of amphotericin B liposomes for industrial applications

Abstract

Amphotericin B (AmB) liposome formulations are very successful in the treatment of fungal infections and leishmaniasis. But higher cost limits its widespread use among people in developing countries. Therefore, we have developed a modified ethanol-injection method for the preparation of AmB liposomes. Two liposomal formulations were developed with dimyristoyl phosphatidylcholine [F-1a] and soya phosphatidylcholine [F-2a], along with egg phosphatidyl glycerol and cholesterol. AmB was dissolved in acidified dimethyl acetamide and mixed with ethanolic lipid solution and rapidly injected in 5% dextrose to prepare liposomes. Liposomes were characterized on the basis of size (~100 nm), zeta (–43.3 ± 2.8 mV) and percent entrapment efficiency (>95%). The in vitro release study showed an insignificant difference (P ≥ 0.05) for 24-hour release between marketed AmB liposomes (AmBisome) and F-1a and F-2a. Proliposome concentrate, used for the preparation of in situ liposomes, was physically stable for more than 3 months at experimental conditions. Similarly, AmB showed no sign of degradation in reconstituted liposomes stored at 2–8°C for more than 3 months. IC₅₀ value of Ambisome (0.18 µg/mL) was comparatively similar to F-1a (0.17 µg/mL) and F-2a (0.16 µg/mL) against intramacrophagic amastigotes. Under experimental conditions, a novel modified method for AmB liposomes is a great success and generates interest for development as a platform technology for many therapeutic drug products.

Keywords::

• Modified ethanol injection method
• proliposomes
• amphotericin B liposome
• fungal infections
• leishmaniasis

Acknowledgment

The authors are highly grateful to Dr. Kalyan Mitra (SAIF, CDRI, Lucknow, India) for providing the facilities for the TEM study. The CDRI communication number of this manuscript is 8055.

Declaration of interest

D.S. is thankful to the Indian Council of Medical Research (New Delhi, India) for providing the SRF fellowship. Financial support from CSIR network project(NWP0035) “Nanomaterial and nanodevices for application in health and diseases” is gratefully acknowledged.