What can light scattering spectroscopy do for membrane‐active peptide studies?

Domingues, Marco M.; Santiago, Patrícia S.; Castanho, Miguel A. R. B.; Santos, Nuno C.

doi:10.1002/psc.1007

Cited by 78 publications

(84 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Zeta potential is an important physical parameter for predicting the vesicles' stability. 31 All UDV formulations showed a negative zeta potential as expected. The formulations containing NaCo had the highest (modular) zeta potential due to the negative charge of this EA in contrast to the nonionic Span 20.…”

Section: Results and Discussion Characterization Of Udv Formulationssupporting

confidence: 71%

Development, characterization, and skin delivery studies of related ultradeformable vesicles: transfersomes, ethosomes, and transethosomes

Ascenso¹,

Raposo²,

Batista³

et al. 2015

IJN

256

150

View full text Add to dashboard Cite

Ultradeformable vesicles (UDV) have recently become a promising tool for the development of improved and innovative dermal and transdermal therapies. The aim of this work was to study three related UDV: transfersomes, ethosomes, and transethosomes for the incorporation of actives of distinct polarities, namely, vitamin E and caffeine, and to evaluate the effect of the carrier on skin permeation and penetration. These actives were incorporated in UDV formulations further characterized for vesicles imaging by transmission electron microscopy; mean vesicle size and polydispersity index by photon correlation spectroscopy; zeta potential by laser-Doppler anemometry; deformability by pressure-driven transport; and incorporation efficiency (IE) after actives quantification by high-performance liquid chromatography. Topical delivery studies were performed in order to compare UDV formulations regarding the release, skin permeation, and penetration profiles. All UDV formulations showed size values within the expected range, except transethosomes prepared by “transfersomal method”, for which size was smaller than 100 nm in contrast to that obtained for vesicles prepared by “ethosomal method”. Zeta potential was negative and higher for formulations containing sodium cholate. The IE was much higher for vitamin E- than caffeine-loaded UDV as expected. For flux measurements, the following order was obtained: transethosomes (TE) > ethosomes (E) ≥ transfersomes (T). This result was consistent with the release and skin penetration profiles for Vitamin E-loaded UDV. However, the releasing results were totally the opposite for caffeine-loaded UDV, which might be explained by the solubility and thermodynamic activity of this active in each formulation instead of the UDV deformability attending to the higher non-incorporated fraction of caffeine. Anyway, a high skin penetration and permeation for all caffeine-loaded UDV were obtained. Transethosomes were more deformable than ethosomes and transfersomes due to the presence of both ethanol and surfactant in their composition. All these UDV were suitable for a deeper skin penetration, especially transethosomes.

show abstract

Section: Results and Discussion Characterization Of Udv Formulationssupporting

confidence: 71%

Development, characterization, and skin delivery studies of related ultradeformable vesicles: transfersomes, ethosomes, and transethosomes

Ascenso¹,

Raposo²,

Batista³

et al. 2015

IJN

256

150

View full text Add to dashboard Cite

show abstract

“…The bacterial suspensions were dispensed into disposable zeta cells with gold electrodes and allowed to equilibrate for 15 min at 25°C. The zeta potential for each sample was calculated from the measured value of the electrophoretic mobility using the Smoluchowski equation (18). The complete experiment was carried out twice for each peptide using independently grown cultures.…”

Section: Methodsmentioning

confidence: 99%

“…In the absence of peptide, the E. coli surface displayed a zeta potential of Ϫ21.9 Ϯ 3.0 mV. This negative surface net charge originates from the negative lipids and lipopolysaccharide (LPS) molecules present in the outer leaflet of the Gram-negative bacteria outer membrane (18,20). Analysis of the electrostatic properties of the E. coli surface by zeta potential measurement, after incubation with either AMP, revealed significant differences between both peptides.…”

Section: Journal Of Biological Chemistry 27541mentioning

confidence: 99%

Escherichia coli Cell Surface Perturbation and Disruption Induced by Antimicrobial Peptides BP100 and pepR

Alves

Melo

Franquelim

et al. 2010

Journal of Biological Chemistry

Self Cite

205

213

View full text Add to dashboard Cite

The potential of antimicrobial peptides (AMPs) as an alternative to conventional therapies is well recognized. Insights into the biological and biophysical properties of AMPs are thus key to understanding their mode of action. In this study, the mechanisms adopted by two AMPs in disrupting the Gram-negative Escherichia coli bacterial envelope were explored. BP100 is a short cecropin A-melittin hybrid peptide known to inhibit the growth of phytopathogenic Gram-negative bacteria. pepR, on the other hand, is a novel AMP derived from the dengue virus capsid protein. Both BP100 and pepR were found to inhibit the growth of E. coli at micromolar concentrations. Zeta potential measurements of E. coli incubated with increasing peptide concentrations allowed for the establishment of a correlation between the minimal inhibitory concentration (MIC) of each AMP and membrane surface charge neutralization. While a neutralization-mediated killing mechanism adopted by either AMP is not necessarily implied, the hypothesis that surface neutralization occurs close to MIC values was confirmed. Atomic force microscopy (AFM) was then employed to visualize the structural effect of the interaction of each AMP with the E. coli cell envelope. At their MICs, BP100 and pepR progressively destroyed the bacterial envelope, with extensive damage already occurring 2 h after peptide addition to the bacteria. A similar effect was observed for each AMP in the concentration-dependent studies. At peptide concentrations below MIC values, only minor disruptions of the bacterial surface occurred.

show abstract

“…Measurements were taken at 25°C using disposable zeta cells with platinum gold-coated electrodes. 24 Prodrug Uptake by Blood to Brain by Capillary Endothelial Cells Blood to brain by capillary endothelial cells were seeded in 6-well culture plates (5 × 10 5 cells/well), incubated for 48 hours and checked under the microscope for confluence and morphology. Then BCECs were washed twice with 1 mL of PBS and preincubated with HBSS buffer for 20 minutes at 37°C.…”

Section: Prodrug Effects On Blood-brain Barrier Integrity In Vitromentioning

confidence: 99%

Mechanism of Brain Targeting by Dexibuprofen Prodrugs Modified with Ethanolamine-Related Structures

Zhou

Jiang

et al. 2015

J Cereb Blood Flow Metab

View full text Add to dashboard Cite

The first molecular insights into how prodrugs modified with ethanolamine-related structures target the brain were generated using an in vitro BBB model and in situ perfusion technique. Prodrugs were delivered safely and efficiently to the brain through tight interaction with the anionic membrane of brain capillary endothelial cells, observed as a shift in zeta potential, followed by uptake into the cells. Prodrugs III and IV carrying primary and secondary amine modifications appeared to enter the brain via energyindependent passive diffusion. In contrast, besides the passive diffusion, prodrugs I and II carrying tertiary amine modifications also appeared to enter via an active process that was energy and pH dependent but was independent of sodium or membrane potential. This active process involved, at least in part, the pyrilamine-sensitive H + /OC antiporter, for which the N,N-diethyl-based compound II showed a much lower affinity than the N,N-dimethyl-based compound I, likely due to steric hindrance. These new insights into brain-targeting mechanisms may help guide efforts to design new prodrugs.

show abstract

What can light scattering spectroscopy do for membrane‐active peptide studies?

Cited by 78 publications

References 41 publications

Development, characterization, and skin delivery studies of related ultradeformable vesicles: transfersomes, ethosomes, and transethosomes

Development, characterization, and skin delivery studies of related ultradeformable vesicles: transfersomes, ethosomes, and transethosomes

Escherichia coli Cell Surface Perturbation and Disruption Induced by Antimicrobial Peptides BP100 and pepR

Mechanism of Brain Targeting by Dexibuprofen Prodrugs Modified with Ethanolamine-Related Structures

Contact Info

Product

Resources

About