The use of simple dynamic mucosal models and confocal microscopy for the evaluation of lyophilised nasal formulations

F.J. McInnes, A.J. Baillie, H. Stevens

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

A range of methods is reported in the literature for assessing hydration and adhesion parameters in the performance of nasal bioadhesive formulations; however, these tests do not always represent the dynamic conditions in the nasal cavity. Lyophilised formulations intended for nasal administration were evaluated using in-vitro tests designed in an attempt to mimic relevant processes in the nasal cavity, and intended to discriminate between different formulations. Initial investigative studies using scanning electron microscopy revealed that the lyophilisate had a highly porous internal structure, expected to provide an ideal porous pathway for re-hydration. Vapour sorption analysis demonstrated substantial weight gain of the lyophilisates on exposure to 95% relative humidity, ranging from 38% to 66%. Agar was used as a synthetic mucosal model designed to provide a standardised quantity of water available for rehydration of the formulations in in-vitro tests. A dynamic adhesion test and a texture analyser sliding test were designed to quantify different aspects of the spreading and adhesion of the hydrating formulations on the synthetic mucosal surface. Examination of the lyophilised formulations using confocal microscopy allowed visualisation and quantification of the initial rate of water ingress into the lyophilisates, which was found to consist of an initial rapid phase, followed by a slower steady-state phase. The results demonstrated that the use of a combination of methods representing the dynamic conditions of the nasal cavity is advisable in order to evaluate a formulation fully and to avoid misleading conclusions
LanguageEnglish
Pages759-767
Number of pages9
JournalJournal of Pharmacy and Pharmacology
Volume59
DOIs
Publication statusPublished - 2007

Fingerprint

Nasal Cavity
Nose
Confocal Microscopy
Intranasal Administration
Water
Fluid Therapy
Humidity
Electron Scanning Microscopy
Weight Gain
Agar
In Vitro Techniques

Keywords

  • nasal drugs
  • pharmacology

Cite this

@article{53aa2d6cc70b4c0392ed57e2ad7f41c4,
title = "The use of simple dynamic mucosal models and confocal microscopy for the evaluation of lyophilised nasal formulations",
abstract = "A range of methods is reported in the literature for assessing hydration and adhesion parameters in the performance of nasal bioadhesive formulations; however, these tests do not always represent the dynamic conditions in the nasal cavity. Lyophilised formulations intended for nasal administration were evaluated using in-vitro tests designed in an attempt to mimic relevant processes in the nasal cavity, and intended to discriminate between different formulations. Initial investigative studies using scanning electron microscopy revealed that the lyophilisate had a highly porous internal structure, expected to provide an ideal porous pathway for re-hydration. Vapour sorption analysis demonstrated substantial weight gain of the lyophilisates on exposure to 95{\%} relative humidity, ranging from 38{\%} to 66{\%}. Agar was used as a synthetic mucosal model designed to provide a standardised quantity of water available for rehydration of the formulations in in-vitro tests. A dynamic adhesion test and a texture analyser sliding test were designed to quantify different aspects of the spreading and adhesion of the hydrating formulations on the synthetic mucosal surface. Examination of the lyophilised formulations using confocal microscopy allowed visualisation and quantification of the initial rate of water ingress into the lyophilisates, which was found to consist of an initial rapid phase, followed by a slower steady-state phase. The results demonstrated that the use of a combination of methods representing the dynamic conditions of the nasal cavity is advisable in order to evaluate a formulation fully and to avoid misleading conclusions",
keywords = "nasal drugs, pharmacology",
author = "F.J. McInnes and A.J. Baillie and H. Stevens",
year = "2007",
doi = "10.1211/jpp.59.6.0002",
language = "English",
volume = "59",
pages = "759--767",
journal = "Journal of Pharmacy and Pharmacology",
issn = "0022-3573",

}

The use of simple dynamic mucosal models and confocal microscopy for the evaluation of lyophilised nasal formulations. / McInnes, F.J.; Baillie, A.J.; Stevens, H.

In: Journal of Pharmacy and Pharmacology, Vol. 59, 2007, p. 759-767.

Research output: Contribution to journalArticle

TY - JOUR

T1 - The use of simple dynamic mucosal models and confocal microscopy for the evaluation of lyophilised nasal formulations

AU - McInnes, F.J.

AU - Baillie, A.J.

AU - Stevens, H.

PY - 2007

Y1 - 2007

N2 - A range of methods is reported in the literature for assessing hydration and adhesion parameters in the performance of nasal bioadhesive formulations; however, these tests do not always represent the dynamic conditions in the nasal cavity. Lyophilised formulations intended for nasal administration were evaluated using in-vitro tests designed in an attempt to mimic relevant processes in the nasal cavity, and intended to discriminate between different formulations. Initial investigative studies using scanning electron microscopy revealed that the lyophilisate had a highly porous internal structure, expected to provide an ideal porous pathway for re-hydration. Vapour sorption analysis demonstrated substantial weight gain of the lyophilisates on exposure to 95% relative humidity, ranging from 38% to 66%. Agar was used as a synthetic mucosal model designed to provide a standardised quantity of water available for rehydration of the formulations in in-vitro tests. A dynamic adhesion test and a texture analyser sliding test were designed to quantify different aspects of the spreading and adhesion of the hydrating formulations on the synthetic mucosal surface. Examination of the lyophilised formulations using confocal microscopy allowed visualisation and quantification of the initial rate of water ingress into the lyophilisates, which was found to consist of an initial rapid phase, followed by a slower steady-state phase. The results demonstrated that the use of a combination of methods representing the dynamic conditions of the nasal cavity is advisable in order to evaluate a formulation fully and to avoid misleading conclusions

AB - A range of methods is reported in the literature for assessing hydration and adhesion parameters in the performance of nasal bioadhesive formulations; however, these tests do not always represent the dynamic conditions in the nasal cavity. Lyophilised formulations intended for nasal administration were evaluated using in-vitro tests designed in an attempt to mimic relevant processes in the nasal cavity, and intended to discriminate between different formulations. Initial investigative studies using scanning electron microscopy revealed that the lyophilisate had a highly porous internal structure, expected to provide an ideal porous pathway for re-hydration. Vapour sorption analysis demonstrated substantial weight gain of the lyophilisates on exposure to 95% relative humidity, ranging from 38% to 66%. Agar was used as a synthetic mucosal model designed to provide a standardised quantity of water available for rehydration of the formulations in in-vitro tests. A dynamic adhesion test and a texture analyser sliding test were designed to quantify different aspects of the spreading and adhesion of the hydrating formulations on the synthetic mucosal surface. Examination of the lyophilised formulations using confocal microscopy allowed visualisation and quantification of the initial rate of water ingress into the lyophilisates, which was found to consist of an initial rapid phase, followed by a slower steady-state phase. The results demonstrated that the use of a combination of methods representing the dynamic conditions of the nasal cavity is advisable in order to evaluate a formulation fully and to avoid misleading conclusions

KW - nasal drugs

KW - pharmacology

UR - http://dx.doi.org/10.1211/jpp.59.6.0002

U2 - 10.1211/jpp.59.6.0002

DO - 10.1211/jpp.59.6.0002

M3 - Article

VL - 59

SP - 759

EP - 767

JO - Journal of Pharmacy and Pharmacology

T2 - Journal of Pharmacy and Pharmacology

JF - Journal of Pharmacy and Pharmacology

SN - 0022-3573

ER -