Temperature-responsive mixed-mode column for the modulation of multiple interactions

Abstract

In this study, mixed-mode chromatography columns have been investigated using multiple analyte interactions. A mixed-mode chromatography column was developed using poly(N-isopropylacrylamide) (PNIPAAm) brush-modified silica beads and poly(3-acrylamidopropyl trimethylammonium chloride) (PAPTAC) brush-modified silica beads. PNIPAAm brush-modified silica beads and PAPTAC brush-modified silica beads were prepared by atom transfer radical polymerization. The beads were then packed into a stainless-steel column in arbitrary compositions. The elution studies evaluated the column performance on hydrophobic, electrostatic, and therapeutic drug samples using steroids, adenosine nucleotide, and antiepileptic drugs as analytes, respectively. Steroids exhibited an increased retention time when the column temperature was increased. The retention of adenosine nucleotides increased with the increasing composition of the PAPTAC-modified beads in the column. The antiepileptic drugs were separated using the prepared mixed-mode columns. An effective separation of antiepileptic drugs was observed on a 10:1 PNIPAAm:PAPTAC column because the balance between the hydrophobic and electrostatic interactions with antiepileptic drugs was optimized for the bead composition. Oligonucleotides were also separated using mixed-mode columns through multiple hydrophobic and electrostatic interactions. These results demonstrate that the developed mixed-mode column can modulate multiple hydrophobic and electrostatic interactions by changing the column temperature and composition of the packed PNIPAAm and PAPTAC beads.

Bioanalytical technologies using temperature-responsive polymers

“…As various types of drugs have ionic properties, ion-exchange chromatography is suitable for their effective retention. Thus, temperature-responsive ion-exchange chromatography was investigated for TDM [ 113 , 114 ].…”

“…Temperature-responsive mixed-mode chromatography using mixed beads effectively exploits electrostatic interactions (Fig. 5 ) [ 114 , 115 ]. Mixed-mode columns using PNIPAAm-modified beads and poly(3-acrylamidopropyltrimethylammonium chloride) (PAPTAC) modified beads have been investigated for temperature-modulated interactions with antiepileptic drugs, which often require TDM [ 114 ].…”

“…5 ) [ 114 , 115 ]. Mixed-mode columns using PNIPAAm-modified beads and poly(3-acrylamidopropyltrimethylammonium chloride) (PAPTAC) modified beads have been investigated for temperature-modulated interactions with antiepileptic drugs, which often require TDM [ 114 ]. In the mixed mode column, PNIPAAm modified beads were used for temperature-modulated hydrophobic interaction with analytes.…”

Bactericidal Ability of Well-Controlled Cationic Polymer Brush Surfaces and the Interaction Analysis by Quartz Crystal Microbalance with Dissipation

“…Well-defined polymer brushes designed using controlled radical polymerization techniques have been actively studied because the relationship between the surface architecture and their functions can be investigated. − Polyelectrolyte (PE) brushes have attracted attention as functional soft interfaces and exhibit unique properties, including super hydrophilicity, lubrication, and adhesion. − To understand the mechanism of these superior properties, fundamental investigations of PE brushes have been performed. These include studies such as neutron reflectivity swelling structure analyses; the effect of the anion species on the swelling structure; the hydrogen-bonded structure of incorporated water; and probing PE brushes using electrochemical impedance spectroscopy. − In the application of PE brushes as biointerfaces, the interactions with biomolecules and cells have been evaluated. − Cationic PE brushes with quaternary ammonium (QA) groups are particularly attractive because they have the potential to provide bactericidal surfaces. − …”

Thermoresponsive block copolymer brush for temperature-modulated hepatocyte separation

“…It exhibits temperaturedependent hydration and dehydration across the phase transition temperature of 32 1C, and shows extension and shrinkage under hydration and dehydration, respectively. 27,28 The unique thermoresponsive properties have been used in biomedical applications, such as temperature-modulated drug and gene delivery systems, [29][30][31][32][33][34] biosensors and bioimaging systems, [35][36][37][38][39] nano-actuators with chemical oscillation, [40][41][42] temperatureresponsive chromatographic analyses using various aqueous mobile phases, [43][44][45][46][47][48][49][50][51] temperature-modulated bioseparation systems, [52][53][54][55][56][57][58] and cell culture substrates and scaffolds. [59][60][61][62][63][64][65][66] For cell separation, target cells were adhered to PNIPAAm at 37 1C; when the temperature was reduced to 20 1C, the hydration and extension of PNIPAAm led to the detachment of adhered cells.…”