Abstract: The invention relates to N-terminal Fmoc-protected peptide combinations that form gels in water and diverse organic solvents, and whose representative overall formulas are: (I), where R.sup.1 is CH.sub.3, CH.sub.2 --CH(CH.sub.3).sub.3, CH(CH.sub.3)CH.sub.2 CH.sub.3, R.sup.2 is H, CH.sub.3, CH.sub.2 OH, (CH.sub.2).sub.n --COOH, (CH.sub.2)4--NH--CO--OCH.sub.2 C.sub.6 H.sub.5, R.sup.3 is dipeptide remainder, m is 0 or 1 and, n is 1 or 2; or (II), where R1 is CH.sub.3, CH.sub.2 --CH(CH.sub.3)2, or CH(CH.sub.3)CH.sub.2 CH3, R2 is CH2--CH(CH3)2, R3 is H, CH.sub.3, CH.sub.2 OH, (CH.sub.2).sub.n --COOH, or (CH.sub.2)4--NH--CO--OCH.sub.2 C.sub.6 H.sub.5, R.sub.4 is tripeptide remainder, m is 0 or 1 and, n is 1 or 2. These types of peptides form gels in aqueous solutions and are biologically compatible and may be useful for drug delivery, antigen delivery and may be useful as food additives to retard spoilage and act as fillers.

Abstract: Methods and compositions for facilitating the transport of a membrane-impermeable extracellular agent having an intracellular activity across the membrane of a cell are provided. The methods involve covalently coupling an amino terminal blocking group to a transport-mediating peptide to form a carrier molecule. The carrier molecule is covalently coupled to the extracellular agent to form a membrane-permeable prodrug. The transport-mediating peptides are highly basic and bind to polyphosphoinositides.

Abstract: Methods and compositions for facilitating the transport of a membrane-impermeable extracellular agent having an intracellular activity across the membrane of a cell are provided. The methods involve covalently coupling an amino terminal blocking group to a transport-mediating peptide to form a carrier molecule. The carrier molecule is covalently coupled to the extracellular agent to form a membrane-permeable prodrug. The transport-mediating peptides are highly basic and bind to polyphosphoinositides.