Ionic strength-dependent denaturation of Thermomyces lanuginosus lipase induced by SDS.

Triglyceride lipase from Thermomyces lanuginosus (TlL) has been reported to be resistant to denaturation by sodium dodecyl sulfate (SDS). We have found that at neutral pH, structural integrity is strongly dependent on ionic strength. In 10mM phosphate buffer and SDS, the lipase exhibits a far-UV CD spectrum similar to other proteins denatured in this surfactant while the near-UV CD spectrum shows a complete loss of tertiary structure, observations supported by steady state fluorescence spectroscopy.

Ghrelin-liposome interactions: characterization of liposomal formulations of an acylated 28-amino acid peptide using CE.

Ghrelin is a pharmacologically interesting peptide hormone due to its effects on appetite and metabolism. The cationic, octanoylated 28 amino acid peptide has a short biological half-life; thus, prolonged release formulations are of interest. Acylated peptides have been suggested to bind to or be incorporated into liposomes.

Recent trends in stabilising peptides and proteins in pharmaceutical formulation - considerations in the choice of excipients.

In the area of peptide and protein pharmaceuticals, both the physical and chemical stability of biopharmaceuticals are critical and need to be optimised when formulating a drug product, in order to optimise the outcome after processing and storage. This review focuses on the effects on the stability from various types of excipient and the choices that have to be made during formulation of drug products containing peptides or proteins. It is illustrated, through examples, how the choice of one excipient over another can affect the stability of a protein drug formulation, along with other problems linked to this choice.

Stability, liposome interaction, and in vivo pharmacology of ghrelin in liposomal suspensions.

Ghrelin is an appetite-stimulating peptide hormone. It is a pharmacologically interesting peptide because of its involvement in e.g.

Determination of dissociation constants between polyelectrolytes and proteins by affinity capillary electrophoresis.

In this manuscript we report the binding affinity between two model proteins, human serum albumin (HSA) and ribonuclease A (RNase A), and negatively charged polyelectrolytes, two different heparin fractions and dextran sulfate, by means of partial filling and affinity capillary electrophoresis. The apparent dissociation constants, K(d), obtained by use of the partial-filling method, between HSA and heparin (17kDa), heparin (3kDa) and dextran sulfate (8kDa) were 33 and 307microM, respectively. A new method was developed to determine affinities that take in account different migration directions between the protein and the polyelectrolyte, which was required to study RNase A.

Alternative routes of administration for systemic delivery of protein pharmaceuticals.

Non-invasive and patient-friendly delivery of proteins are important targets for protein formulation development. Traditionally, a lyophilized cake for reconstitution followed by s.c.

Preliminary studies of the physical stability of a glucagon-like peptide-1 derivate in the presence of metal ions.

The physical stability and the secondary structure of a glucagon-like peptide-1 derivative were investigated in the presence of the metal ions Al(3+), Zn(2+), Mg(2+), and K(+), known as possible leachables from container-closure systems. Metal ions were investigated in concentrations of 0-50 ppm. Test solutions of the peptide were exposed to elevated temperature (25 degrees C) and rotation (37 degrees C) for up to 4 weeks.

Ability to differentiate between cp and ncp BVDV by microarrays: towards an application in clinical veterinary medicine?

Microarray expression profiling provides a comprehensive portrait of the transcriptional world enabling us to view the organism as a 'system' that is more than the sum of its parts. The vigilance of cells to environmental change, the alacrity of the transcriptional response, the short half-life of cellular mRNA and the genome-scale nature of the investigation collectively explain the power of this method. These same features pose the most significant experimental design and execution issues which, unless surmounted, predictably generate a distorted image of the transcriptome.