Liposomes as a Drug Delivery System: Optimization Studies

  • Gregory Gregoriadis
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 238)


The great structural versatility of liposomes, their relatively inoccuous nature and ability to incorporate a wide spectrum of biologically active agents have led to the adoption of the system by numerous workers as a drug carrier.1,2 Proposed applications2 for liposome-mediated drug delivery include antimicrobial3 and cancer therapy,4 metal detoxification,5 oral adminstration of hormones, enzymes and other drugs which are either unstable in or unabsorbable by the gut,6 vaccines,7 activation of macrophages,8 ligand-mediated targeting to accessible cells in vivo,9 topical uses of drugs (eg, skin and eye diseases)10 and as a substitute for red blood cells (haemosomes).11 Some of these applications seem realistic enough for early clinical development, whilst others must await further advances.2 In parallel, there has been considerable progress in liposome technology1 and related achievements have ensured in many cases adoption of the liposome system by the Industry.12 Technological achievements in this area include development of methods for high yield drug entrapment, achieving a relatively low lipid:drug ratio.1


High Density Lipoprotein Phospholipid Molecule Small Unilamellar Vesicle Solute Retention Solute Loss 
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Copyright information

© Plenum Press, New York 1988

Authors and Affiliations

  • Gregory Gregoriadis
    • 1
  1. 1.Medical Research Council Group Academic Department of MedicineRoyal Free Hospital School of MedicineLondonUK

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