Irina Ermolina - Academia.edu (original) (raw)

Papers by Irina Ermolina

Journal of Pharmacy and Pharmacology, 2009

The absorbed markers were excreted in urine as metabolites. Pellitorine and sarmentine exhibited ... more The absorbed markers were excreted in urine as metabolites. Pellitorine and sarmentine exhibited different tissue affinities. Based on pellitorine, sarmentine and sarmentosine, the predicted shelf life (t 90) of the extract was 16 months at 25 C. The markers followed the zero-order reaction indicating that their degradation was independent of initial concentration. Conclusion The chloroform extract of the leaves of Piper sarmentosum has promising antiobesity activity by inhibiting vascularisation to adipocytes with good safety profile.

The Journal of Physical Chemistry B, 2000

The dynamic structures of native and hydrophobized (by covalent attachment of palmitoyl chains) g... more The dynamic structures of native and hydrophobized (by covalent attachment of palmitoyl chains) glucose oxidase were studied by time-domain dielectric spectroscopy (TDDS). Analysis of the dipole correlation function for both types of the enzyme showed that the decay of the correlation function of the macromolecule motion can be presented as a sum of components corresponding to different kinds of protein motion: isotropic rotation of the protein molecule as a whole, anisotropic Brownian tumbling of subunits, and anisotropic intramolecular motion of polar groups and substructures. The slowest relaxation time was found to be longer for the modified enzyme than for the native enzyme. The dielectric strengths for all relaxation processes, as well as the dipole moment and the molecular volume, were also larger for the modified glucose oxidase. The observed differences between various types of the dipole motion for the native and modified glucose oxidase are discussed.

This study was performed to evaluate the application of impedance spectroscopy in the characteriz... more This study was performed to evaluate the application of impedance spectroscopy in the characterization of a frozen matrix during annealing and in the recording of the impact of annealing on the duration of primary drying. The results shows increments in the product capacitance during annealing that can be applied to explain the decrease in primary drying of the matrix.

Two IgG formulations, one with 5% sucrose and the other with 5% Mannitol:Sucrose (ratio 4:1) both... more Two IgG formulations, one with 5% sucrose and the other with 5% Mannitol:Sucrose (ratio 4:1) both in 20mM Histidiine 0.01% Tween 20 pH 6.5, were freeze dried in a Telstar freeze dryer equipped with Pirani and Baratron sensors and a Sciospec® five-channel through vial impedance spectroscopy (TVIS) system. The TVIS parameter C'(100kHz) (i.e. the real part electrical capacitance measured at 100 kHz) is sensitive to the amount of ice in the vial. By following the recovery of its time profile during primary drying, it was possible to determine the primary drying endpoint. The TVIS endpoint of the sucrose edge vial occurred well before the onset of the Pirani endpoint suggesting that Pirani was more sensitive to the core vials. The TVIS endpoint in the core vials also occurred somewhere close to the midpoint of the Pirani endpoint suggesting that other core vials were still in primary drying.

Cite as:Jeeraruangrattana, Y. et al. (2018) Application of Impedance Based Technology to Investig... more Cite as:Jeeraruangrattana, Y. et al. (2018) Application of Impedance Based Technology to Investigate the Collapse of Freeze-dried. Poster Presentation at Freeze Drying of Pharmaceuticals and Biologicals, Sept 18-21 (2018), Garmisch-Partenkirchen, GermanyPoster presentation at Freeze Drying of Pharmaceuticals and Biologicals, Sept 18-21 (2018), Garmisch-Partenkirchen, Germany

Hydrogels have been intensively studied for drug delivery and tissue engineering applications. Of... more Hydrogels have been intensively studied for drug delivery and tissue engineering applications. Of particular interest has been those hydrogels which undergo temperature induced sol-gel transitions and offer the possibility of in situ gel formation following injection. The main focus of this work was to evaluate the use of impedance spectroscopy in characterizing the thermogelation of hyaluronic acid (HA) and methylcellulose (MC) hydrogels, a system with potential to gel at body temperature.

Cite as:Jeeraruangrattana, Y. et al. (2017) Prediction of the Collapse of Freeze-Dried Lactose So... more Cite as:Jeeraruangrattana, Y. et al. (2017) Prediction of the Collapse of Freeze-Dried Lactose Solution using Through Vial Impedance Spectroscopy (TVIS). Poster Presentation at the 8th APS International PharmSci Conference, 5-7th September 2017, Hertforshire, UK.Poster presentation at The 8th APS International PharmSci Conference, 5-7th September 2017, Hertforshire, UK

Dielectric Relaxation in Biological Systems, 2015

In the first part of the chapter, dielectric spectroscopy studies of globular proteins in aqueous... more In the first part of the chapter, dielectric spectroscopy studies of globular proteins in aqueous solutions in native and denatured states are reviewed. Here we discuss the mechanisms of two major dielectric relaxation processes (γ- and β-dispersions) and one minor process (δ-dispersion) observed in the diluted globular protein solutions. Effects of protein concentration, temperature, pH, and denaturants were also summarized. The second part of the chapter presents the dielectric properties of proteins in natural membrane fragments and living cells membrane. Ferroelectric behavior was observed for the first time for the package of bacteriorhodopsin membrane fragments oriented in the electric field. Here, a discussion is also presented about progress and problems related to the observation of proteins in living cells using dielectric spectroscop

AAPS PharmSciTech, 2013

The control of the amorphous and crystalline states of drugs and excipients is important in many ... more The control of the amorphous and crystalline states of drugs and excipients is important in many instances of product formulation, manufacture, and packaging, such as the formulation of certain (freezedried) fast melt tablets. This study examines the use of terahertz-pulsed spectroscopy (TPS) coupled with two different data analytical methods as an off-line tool (in the first instance) for assessing the degree of crystallinity in a binary mixture of amorphous and polycrystalline sucrose. The terahertz spectrum of sucrose was recorded in the wave number range between 3 and 100 cm −1 for both the pure crystalline form and for a mixture of the crystalline and amorphous (freeze-dried) form. The THz spectra of crystalline sucrose showed distinct absorption bands at ∼48, ∼55, and ∼60 cm −1 while all these features were absent in the amorphous sucrose. Calibration models were constructed based on (1) peak area analysis and (2) partial least square regression analysis, with the latter giving the best LOD and LOQ of 0.76% and 2.3%, respectively. The potential for using THz spectroscopy, as a quantitative in-line tool for percent crystallinity in a range of complex systems such as conventional tablets and freeze-dried formulations, is suggested in this study.

Cite as:Pandya et al. (2018). Poster Presentation at Freeze Drying of Pharmaceuticals and Biologi... more Cite as:Pandya et al. (2018). Poster Presentation at Freeze Drying of Pharmaceuticals and Biologicals,18-21st September 2018, Garmisch Partenkirchen, GermanyTo demonstrate the impact of vial location on the drying rate using two parameters of non-product invasive through vial impedance spectroscopy (TVIS). These include: (i) the peak imaginary amplitude, C"PEAK, which is a direct measure of ice mass in the vial, and (ii) the peak frequency, FPEAK, which is sensitive to a change in the shape of the ice interface.

PURPOSE To demonstrate the impact of vial location on the drying rate using two parameters of non... more PURPOSE To demonstrate the impact of vial location on the drying rate using two parameters of non-product invasive through vial impedance spectroscopy (TVIS). These include: (i) the peak imaginary amplitude, C"PEAK, which is a direct measure of ice mass in the vial, and (ii) the peak frequency, FPEAK, which is sensitive to a change in the shape of the ice interface. <br>

Journal of Pharmacy and Pharmacology, 2009

The absorbed markers were excreted in urine as metabolites. Pellitorine and sarmentine exhibited ... more The absorbed markers were excreted in urine as metabolites. Pellitorine and sarmentine exhibited different tissue affinities. Based on pellitorine, sarmentine and sarmentosine, the predicted shelf life (t 90) of the extract was 16 months at 25 C. The markers followed the zero-order reaction indicating that their degradation was independent of initial concentration. Conclusion The chloroform extract of the leaves of Piper sarmentosum has promising antiobesity activity by inhibiting vascularisation to adipocytes with good safety profile.

The Journal of Physical Chemistry B, 2000

The dynamic structures of native and hydrophobized (by covalent attachment of palmitoyl chains) g... more The dynamic structures of native and hydrophobized (by covalent attachment of palmitoyl chains) glucose oxidase were studied by time-domain dielectric spectroscopy (TDDS). Analysis of the dipole correlation function for both types of the enzyme showed that the decay of the correlation function of the macromolecule motion can be presented as a sum of components corresponding to different kinds of protein motion: isotropic rotation of the protein molecule as a whole, anisotropic Brownian tumbling of subunits, and anisotropic intramolecular motion of polar groups and substructures. The slowest relaxation time was found to be longer for the modified enzyme than for the native enzyme. The dielectric strengths for all relaxation processes, as well as the dipole moment and the molecular volume, were also larger for the modified glucose oxidase. The observed differences between various types of the dipole motion for the native and modified glucose oxidase are discussed.

This study was performed to evaluate the application of impedance spectroscopy in the characteriz... more This study was performed to evaluate the application of impedance spectroscopy in the characterization of a frozen matrix during annealing and in the recording of the impact of annealing on the duration of primary drying. The results shows increments in the product capacitance during annealing that can be applied to explain the decrease in primary drying of the matrix.

Two IgG formulations, one with 5% sucrose and the other with 5% Mannitol:Sucrose (ratio 4:1) both... more Two IgG formulations, one with 5% sucrose and the other with 5% Mannitol:Sucrose (ratio 4:1) both in 20mM Histidiine 0.01% Tween 20 pH 6.5, were freeze dried in a Telstar freeze dryer equipped with Pirani and Baratron sensors and a Sciospec® five-channel through vial impedance spectroscopy (TVIS) system. The TVIS parameter C'(100kHz) (i.e. the real part electrical capacitance measured at 100 kHz) is sensitive to the amount of ice in the vial. By following the recovery of its time profile during primary drying, it was possible to determine the primary drying endpoint. The TVIS endpoint of the sucrose edge vial occurred well before the onset of the Pirani endpoint suggesting that Pirani was more sensitive to the core vials. The TVIS endpoint in the core vials also occurred somewhere close to the midpoint of the Pirani endpoint suggesting that other core vials were still in primary drying.

Cite as:Jeeraruangrattana, Y. et al. (2018) Application of Impedance Based Technology to Investig... more Cite as:Jeeraruangrattana, Y. et al. (2018) Application of Impedance Based Technology to Investigate the Collapse of Freeze-dried. Poster Presentation at Freeze Drying of Pharmaceuticals and Biologicals, Sept 18-21 (2018), Garmisch-Partenkirchen, GermanyPoster presentation at Freeze Drying of Pharmaceuticals and Biologicals, Sept 18-21 (2018), Garmisch-Partenkirchen, Germany

Hydrogels have been intensively studied for drug delivery and tissue engineering applications. Of... more Hydrogels have been intensively studied for drug delivery and tissue engineering applications. Of particular interest has been those hydrogels which undergo temperature induced sol-gel transitions and offer the possibility of in situ gel formation following injection. The main focus of this work was to evaluate the use of impedance spectroscopy in characterizing the thermogelation of hyaluronic acid (HA) and methylcellulose (MC) hydrogels, a system with potential to gel at body temperature.

Cite as:Jeeraruangrattana, Y. et al. (2017) Prediction of the Collapse of Freeze-Dried Lactose So... more Cite as:Jeeraruangrattana, Y. et al. (2017) Prediction of the Collapse of Freeze-Dried Lactose Solution using Through Vial Impedance Spectroscopy (TVIS). Poster Presentation at the 8th APS International PharmSci Conference, 5-7th September 2017, Hertforshire, UK.Poster presentation at The 8th APS International PharmSci Conference, 5-7th September 2017, Hertforshire, UK

Dielectric Relaxation in Biological Systems, 2015

In the first part of the chapter, dielectric spectroscopy studies of globular proteins in aqueous... more In the first part of the chapter, dielectric spectroscopy studies of globular proteins in aqueous solutions in native and denatured states are reviewed. Here we discuss the mechanisms of two major dielectric relaxation processes (γ- and β-dispersions) and one minor process (δ-dispersion) observed in the diluted globular protein solutions. Effects of protein concentration, temperature, pH, and denaturants were also summarized. The second part of the chapter presents the dielectric properties of proteins in natural membrane fragments and living cells membrane. Ferroelectric behavior was observed for the first time for the package of bacteriorhodopsin membrane fragments oriented in the electric field. Here, a discussion is also presented about progress and problems related to the observation of proteins in living cells using dielectric spectroscop

AAPS PharmSciTech, 2013

The control of the amorphous and crystalline states of drugs and excipients is important in many ... more The control of the amorphous and crystalline states of drugs and excipients is important in many instances of product formulation, manufacture, and packaging, such as the formulation of certain (freezedried) fast melt tablets. This study examines the use of terahertz-pulsed spectroscopy (TPS) coupled with two different data analytical methods as an off-line tool (in the first instance) for assessing the degree of crystallinity in a binary mixture of amorphous and polycrystalline sucrose. The terahertz spectrum of sucrose was recorded in the wave number range between 3 and 100 cm −1 for both the pure crystalline form and for a mixture of the crystalline and amorphous (freeze-dried) form. The THz spectra of crystalline sucrose showed distinct absorption bands at ∼48, ∼55, and ∼60 cm −1 while all these features were absent in the amorphous sucrose. Calibration models were constructed based on (1) peak area analysis and (2) partial least square regression analysis, with the latter giving the best LOD and LOQ of 0.76% and 2.3%, respectively. The potential for using THz spectroscopy, as a quantitative in-line tool for percent crystallinity in a range of complex systems such as conventional tablets and freeze-dried formulations, is suggested in this study.

Cite as:Pandya et al. (2018). Poster Presentation at Freeze Drying of Pharmaceuticals and Biologi... more Cite as:Pandya et al. (2018). Poster Presentation at Freeze Drying of Pharmaceuticals and Biologicals,18-21st September 2018, Garmisch Partenkirchen, GermanyTo demonstrate the impact of vial location on the drying rate using two parameters of non-product invasive through vial impedance spectroscopy (TVIS). These include: (i) the peak imaginary amplitude, C"PEAK, which is a direct measure of ice mass in the vial, and (ii) the peak frequency, FPEAK, which is sensitive to a change in the shape of the ice interface.

PURPOSE To demonstrate the impact of vial location on the drying rate using two parameters of non... more PURPOSE To demonstrate the impact of vial location on the drying rate using two parameters of non-product invasive through vial impedance spectroscopy (TVIS). These include: (i) the peak imaginary amplitude, C"PEAK, which is a direct measure of ice mass in the vial, and (ii) the peak frequency, FPEAK, which is sensitive to a change in the shape of the ice interface. <br>