In vivo deamidation characterization of monoclonal antibody by LC/MS/MS.

The spontaneous nonenzymatic deamidation of glutaminyl and asparaginyl residues of peptides and proteins has been observed both in vitro and in vivo. Deamidation may change the structure and function of a peptide or protein, potentially resulting in decreased bioactivity, as well as alterations in pharmacokinetics and antigenicity of the protein pharmaceutical. Therefore, it is necessary to monitor the effect of storage and formulation conditions on deamidation of a protein drug candidate.

Analysis of nonderivatized neutral and sialylated oligosaccharides by electrospray mass spectrometry.

An HPLC/MS method has been developed that allows rapid, direct analysis of underivatized sialylated as well as neutral oligosaccharides. The method involves the separation of oligosaccharides from salts and proteins using RP-HPLC with a formic acid/acetonitrile/water mobile phase system and on-line electrospray mass spectrometry analysis in the positive ion mode. Under the solution conditions employed, both neutral and acidic (sialylated) oligosaccharides are protonated and therefore detected.

Relating quality of center-based child care to early cognitive and language development longitudinally.

How quality of center-based child care relates to early cognitive and language development was examined longitudinally from 6 to 36 months of age in a sample of 89 African American children. Both structural and process measures of quality of child care were collected through observation of the infant classroom. Results indicated that higher quality child care was related to higher measures of cognitive development (Bayley Scales of Infant Development), language development (Sequenced Inventory of Communication Development), and communication skills (Communication and Symbolic Behavior Scales) across time, even after adjusting for selected child and family characteristics.

Development of improved high-performance liquid chromatography conditions for nonisotopic detection of isoaspartic acid to determine the extent of protein deamidation.

A rapid and accurate ion-pairing reversed-phase high-performance liquid chromatography (IP-RP-HPLC) procedure has been developed for nonisotopic detection of isoaspartic acid residues in protein or peptides resulting from deamidation of asparagine residues. The IP-RP-HPLC procedure specifically detects and quantifies S-adenosylhomocysteine (SAH). SAH is a by-product of the reaction between protein isoaspartyl methyltransferase (PIMT), S-adenosylmethionine (SAM), and isoaspartic acid residues.

Characterization and establishment of specifications for biopharmaceuticals.

This paper describes the role of product characterization and product specifications in the context of an overall control strategy. Due to advances in analytical characterization and biotechnology manufacturing methods, product characterization can now be used as an effective means of assessing the impact of manufacturing process changes on product quality, safety and efficacy, hence obviating the need for repeating clinical testing each time a manufacturing process change is made. The ICH specifications guidance document can serve a key role in harmonising test requirements and regulatory practices with regard to produce characterization.