At HTD we offer several analytical services.
The approach we use for formulation is to identify the most stable conformation of the protein using a number of biophysical approaches. Characterizing and stabilizing the conformation of a molecule is key to developing a successful, stable, and robust formulation.
Particle Siza Analysis using Dynamic Light Scattering (DLS)
Dynamic Light Scattering can be used to determine the average hydrodynamic diameter in colloidal systems where the particles are smaller than 2,000 nm. We have successfully used this technique to determine the size of protein monomers and aggregates, to study protein folding and unfolding and complexation and also to determine the particle size of nanoparticles such as liposomes. We use DLS to determine stability of drugs in liquid and solid-state. We have also developed a method for determination of lipid content in liposomes using DLS.
Conformational Analysis of Proteins and Antibodies
Differential Scanning Florimetry (DSF) for Protein & Antibody Screening
Protein and antibody screening using nano DSF
We utilize a dye-free approach to analyzing protein conformation by Differential Scanning Fluorimetry (DSF). Our instruments allows us to accurately measure the inherent conformational of the molecule using only 10 ul of sample and analyze up to 48 samples simultaneously in a single run. We optimize the formulation parameters using onset temperature, melting temperature, and thermodynamic parameters such as ∆G and ∆H.
Differential Scanning Calorimetry
DSC is used for determination of solid-dtate structure of powders, polymer films and lyophilized cakes. Thermal stability of the solid is investigated by measuring Tg, Tc, Tm and ∆H. for a review of different applizations of solid-state DSC see our application note for DSC.
DSC can also be used to measure Tg' and Tc in a frozen liquid. Such information is important for freeze-drying cycle development.
How to Determine Glass Transition Temperature
Determination of Glass Transition Temperature
Second Derivative UV Spectroscopy For Protein Conformation Analysis
Our expertise in second-derivative spectroscopy provides a unique prospective in analysis of subtle changes in the tertiary structure of proteins during formulation development. Microenvironments of three amino acids can be monitored simultaneously and using advanced multi-variate DOE methodology, we can rapidly identify potential formulations and rationale all the formulation components.
Protein conformational analysis using second derivative UV spectroscopy (2dUV)
Protein Chip Bioanalyzer For Determination of Protein Intergrity