The research area is in the field of pharmaceutical analysis and in
particular it concerns the development and application of
chromatographic techniques (HPLC and GC-MS) and capillary
electrophoresis (CE) in analysis of bioactive compounds.
The specific subjects of research are:
1) Development and application of electrokinetic systems based on
complex pseudostationary phases (mixed micelle,
micelle-cyclodextrin, microemulsions, proteins).
2) Development and application of capillary isoelectric focusing for characterization of therapeutic proteins (in particular monoclonal antibodies).
3) Microfluidic paper-based analytical device
1. Development and application of electrokinetic systems based
on complex pseudostationary phases.
Improved separation selectivity in electrokinetic systems can be
achieved by supplementing the electrophoretic running buffer with
additives able to establish reversible interactions with the
solutes to be separated. Among the additives, surfactants are very
successful; they are used at concentration higher the critical
micelle concentration (cmc). Under these condition a micellar
pseudostationary phase is obtained. In this field the research
activity has been addressed to the development of new micellar
systems based on mixed micelle (from different surfactants) such as
sodium dodecyl sulfate (SDS) and bile salts. Further, the role of
cyclodextrins as chiral additives in electrokinetic systems has
been considered. Finally, microemulsion based on oils such as
heptane and octane in the presence of surfactants and
co-surfactants, have been applied as separation pseudostationary
phases. The possible role of the components of the considered
pseudostationaty phases can be hypothesized by means of the
evaluation of characteristic chromatographic parameters such as
selectivity, resolution, capacity factor, and efficiency;
furthermore, also physico-chemical parameters such as zeta
potential, ionic radius of the micelle aggregates,
inclusion/complexation constants and kinetic constants can be
determinated in order to characterize the complex systems.
The use of proteins as additives to the running buffer belongs to
this research field; proteins can be considered as useful chiral
selectors.
In general the development of all of these described complex
systems can be advantageously carried out by means of chemometric
and Quality by Design approaches: this part of the research
activity is in collaboration with a team of the
University of Florence. The proposed CE systems allowed
to achieve interesting and useful methods for related substances
analysis in pharmaceuticals.
2. Capillary isoelectricfocusing (CiEF)
CiEF is developed and applied to study and characterize the charge variants of therapeutic proteins and in particular of monoclonal antibodies, allowing the determination of the isoelectric points of the charge variants. This characterization is of fundamental importance in the quality control of biotechnological drugs.
3. The fabrication of microfluidic chips can be achieved using chromatographic paper. By employing a wax printer, hydrophobic boundaries can be defined for channels, allowing for fluid flow regulated by capillary action thus avoiding external pumps. The resulting devices, known as microfluidic paper-based analytical devices (µPADs), are used as platforms for reactions that enable the colorimetric detection of various analytes of interest whose quantitation can be achieved by scanning using a smartphone. Since the movement of fluid within the paper-based microfluidic channels of the device is correlated with its architecture, it's essential to dimensionally optimize the device prior to its utilization. In this research line, the Analytical Quality by Design (AQbD) approach is adopted for this optimization purpose.