Biomedical Applications of Biomedical Applications of Scanning Probe MicroscopyScanning Probe Microscopy

Dr James R SmithDr James R SmithSchool of Pharmacy and Biomedical ScienceSchool of Pharmacy and Biomedical Science

University of PortsmouthUniversity of Portsmouth

ContentContent

What is Scanning Probe Microscopy (SPM) ?What is Scanning Probe Microscopy (SPM) ? Principles of SPMPrinciples of SPM How does it differ from SEM/TEM ?How does it differ from SEM/TEM ? SPM Facilities at PortsmouthSPM Facilities at Portsmouth Selected Case StudiesSelected Case Studies SummarySummary QuestionsQuestions

What is SPM ?What is SPM ?

SPM is a revolutionary technique which SPM is a revolutionary technique which allows:allows:– 3-D imaging3-D imaging– nanometre or micrometre scalenanometre or micrometre scale– imaging in a variety of environmentsimaging in a variety of environments– with minimal sample preparationwith minimal sample preparation

SPM TechniquesSPM Techniques

SPM is a generic name for a number of related SPM is a generic name for a number of related ‘probe’ techniques:‘probe’ techniques:– Scanning Tunnelling Microscopy (STM)Scanning Tunnelling Microscopy (STM)

– Atomic Force Microscopy (AFM)Atomic Force Microscopy (AFM)

– others, such as Scanning Thermal Microscopy (SThM), others, such as Scanning Thermal Microscopy (SThM), Scanning Electrochemical Microscopy (SECM), Scanning Electrochemical Microscopy (SECM), Magnetic Force Microscopy (MFM)Magnetic Force Microscopy (MFM)

Historical BackgroundHistorical Background

Scanning Tunnelling Microscopy (STM) Scanning Tunnelling Microscopy (STM) was first reported in 1982 by Binnig et al.was first reported in 1982 by Binnig et al.

Atomic Force Microscope (AFM) first Atomic Force Microscope (AFM) first appeared in 1986appeared in 1986

Commercial SPM instruments capable of Commercial SPM instruments capable of STM and AFM operation available in 1992STM and AFM operation available in 1992

Principles of AFMPrinciples of AFM

Advantages of SPM over TEM Advantages of SPM over TEM and SEMand SEM

Nanometre/atomic resolutionNanometre/atomic resolution Accurate height measurements to within 1 angstromAccurate height measurements to within 1 angstrom Three-dimensional representation of imagesThree-dimensional representation of images Does not require UHVDoes not require UHV Ability to perform studies in aqueous environmentsAbility to perform studies in aqueous environments Manipulation of surfaces on sub-nanometre scaleManipulation of surfaces on sub-nanometre scale

Other Information from SPMOther Information from SPM

Surface roughnessSurface roughness Surface areaSurface area Hardness/softnessHardness/softness ElasticityElasticity AdhesionAdhesion FrictionFriction

Nanoindentation of Bacterial CellsNanoindentation of Bacterial Cells

SPM Facilities at PortsmouthSPM Facilities at Portsmouth

TopoMetrix Discoverer TMX2000 Modular SPM

Biomedical Applications of Biomedical Applications of SPM at PortsmouthSPM at Portsmouth

Surface metrication of hip prosthesesSurface metrication of hip prostheses Contact lens manufacture and foulingContact lens manufacture and fouling Hair structure and diseaseHair structure and disease Biocide actionBiocide action Polymer binding to human cellsPolymer binding to human cells Surface roughness of skinSurface roughness of skin RNA/DNA secondary structureRNA/DNA secondary structure

– anti-cancer drug designanti-cancer drug design

Biodeterioration and ControlBiodeterioration and Control

Biofilm contamination on Biofilm contamination on an intraocular lensan intraocular lens

Action of a biocide on Action of a biocide on E. coliE. coli

Surface Metrication of Hip Surface Metrication of Hip ProsthesesProstheses

Soft Contact Lens ManufactureSoft Contact Lens Manufacture

Pigment distribution on aPigment distribution on atinted soft contact lens tinted soft contact lens (above)(above) and surface and surface roughness roughness (left)(left)

Polypropylene injection mouldPolypropylene injection mould

Human HairHuman Hair

A=‘A’-layer, B=exocuticle,A=‘A’-layer, B=exocuticle,C=endocuticle C=endocuticle (above)(above)

Surface roughness/line profileSurface roughness/line profile

Same hair sample imaged under waterSame hair sample imaged under watershowing swelling showing swelling (right)(right)

SummarySummary Nanometre/atomic resolutionNanometre/atomic resolution Accurate height measurements to within 1 angstromAccurate height measurements to within 1 angstrom Three-dimensional representation of imagesThree-dimensional representation of images Does not require UHVDoes not require UHV Ability to perform studies in aqueous environmentsAbility to perform studies in aqueous environments Minimal sample preparationMinimal sample preparation Minimal damage to sampleMinimal damage to sample Manipulation of surfaces on sub-nanometre scaleManipulation of surfaces on sub-nanometre scale

AcknowledgementsAcknowledgements

Dr S A Campbell - PortsmouthDr S A Campbell - Portsmouth Prof F C Walsh - PortsmouthProf F C Walsh - Portsmouth Dr B F Shahgaldi - St Thomas’ Hospital, LondonDr B F Shahgaldi - St Thomas’ Hospital, London Dr J A Swift - Unilever/De Montfort UniversityDr J A Swift - Unilever/De Montfort University Dr A Gough - Alberto-Culver Company (UK) LtdDr A Gough - Alberto-Culver Company (UK) Ltd Dr D H Morton - Clinic For Special Children, Dr D H Morton - Clinic For Special Children,

Philadelphia Philadelphia Staff and students at PortsmouthStaff and students at Portsmouth