Peptide-drug complexes

In addition, hydrophilic substances can be taken up into the membrane when complexes with hydrophobic counter-ions are formed. This property has been exploited for increasing the uptake of peptidic drugs by, for example, salicylate [157],... 

Peptide hormones and neurotransmitters are primary agents of communication between different cell types In the body of complex living systems Including man. Thus, analogs of natural peptide hormones and neurotransmitters with appropriate properties have exceptional potential as drugs. Despite this potential and the need for peptide drugs, development has been slow. Why ... 

Determination of aluminium in water for injection as a fluorescent complex Determination of stability of peptide drugs in solution Fluorescent derivatives and flow injection analysis... 

If the peptide drug binds strongly to the matrix protein(s), the peptide would co-precipitate with the proteins. A small volume of a strong acid (such as HC1) can be added to the sample to have the drug-protein complex dissociate prior to precipitation. 

Drug-DNA Interactions in Solution Acridine Mutagen, Anthracycline Antitumor, and Peptide Antibiotic Complexes... 

In this chapter, the preparation methods and efficacy of novel lipid particles such as polymer-coated liposomes and polymer-liposome complexes for peptide drug delivery are described. Both systems have common characteristics of mucoadhesion. 

The mucoadhesion of the liposome-based formulations was examined both in vitro and in vivo. Using CLSM, the penetration of polymer-coated liposomes or polymer-liposome complexes into a layer of mucus in the rats after oral administration was confirmed. The pharmacological action of the model peptide drugs... 

If we look a little more deeply into this definition, the first question is which type of system could we encapsulate This could range from small molecules (some try to encapsule water) to quite complex ones (peptides, drug, DNA). It could be a mix of these molecules, or complex structures like viruses, protoplasts or even complete biological cells. Inside the capsules, the active system could be in the form of a solution, a suspension or an emulsion. 

Rutenber, E., Fauman, E.B., Keenan, R.J., Fong, S., Furth, P.S., Ortiz de Montellano, P.R., Meng, E., Kuntz, I.D., DeCamp, D.L., Salto, R. (1993) Structure of a non-peptide inhibitor complexed with HIV-1 protease. Developing a cycle of structure-based drug design, J. Biol. 

In recent years, ACE has been used to study ligand-receptor interactions and determine the binding constants of formed complexes (41-43). Some typical applications include enzyme-inhibitor, DNA-peptide, protein-sugar, peptide-drug, and antibody-antigen (Ab-Ag), etc. We will focus on Ab-Ag interactions. 

Intemasal delivery of peptide and protein drugs is severely restricted by pre-systemic elimination due to enz5miatic degradation or mucociliary clearance and by the limited extent of mucosal membrane permeability. a-CyD has been shown to remove some fatty acids from nasal mucosa and to enhance the nasal absorption of leuprolide acetate in rats and dogs. The utility of chemically modified CyDs as absorption enhancers for peptide drugs in rats has been demonstrated. For example, DM-P-CyD was shown to be a potent enhancer of insulin absorption in rats, and a minimal effective concentration of DM-(3-CyD for absorption enhancement exerted only a mild effect on the in vitro ciliary movement.The scope of interaction of insulin with CyDs is limited, because CyDs can only partially include the hydrophobic amino acid residues in peptides with small stability constants. Under in vivo conditions, these complexes will readily dissociate into separate components, and hence the displacement by membrane lipids may further destabilize the complexes. The direct interaction of peptides with CyDs is therefore of minor importance in the enhancement of nasal absorption. Of the hydrophilic CyDs tested, DM- 3-CyD had the most prominent inhibitory effect on the enzymatic degradation of both BLA and insulin in rat nasal tissue homogenates. Because of the limited interaction between peptides and CyDs,... 

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