WO2010038038A1

WO2010038038A1 - Optical microscopy with nmr

Info

Publication number: WO2010038038A1
Application number: PCT/GB2009/002361
Authority: WO
Inventors: Gareth Wynn Vaughan Cave; Martin Bencsik; Robert Morris
Original assignee: The Nottingham Trent University
Priority date: 2008-10-02
Filing date: 2009-10-02
Publication date: 2010-04-08
Also published as: GB0818023D0; GB2464110A

Abstract

An optical microscope (1) has a lens housing comprising an objective lens defining an optical axis and a stage axially separated from the objective lens along the optical axis, for receiving a specimen for optical examination through the objective lens. A detachable NMR or ESR signal acquisition module is disposed on the optical microscope and adapted to generate an NMR or ESR signal acquisition volume between the objective lens and the stage external to the module so as to allow lateral access to the signal acquisition volume. The module may comprise a sample mount (10) comprising a platform having a base for being received onto an optical microscope stage (7), a first magnet (16) supported thereon for providing a static magnetic field, an RF coil (17), and a specimen support structure disposed external to the first magnet and the RF coil. The first magnet and RF coil define an NMR or ESR signal acquisition volume external to the module and on the optical axis at a focal plane of the microscope lens.

Description

OPTICAL MICROSCOPY WITH NMR

The present invention relates to apparatus for facilitating optical microscopy at the same time as acquiring nuclear magnetic resonance (NMR) signals or electron spin resonance (ESR) signals from a sample.

GB 2245365 describes a sample mount for NMR microscopy in which an RF coil and additional electronics are mounted between a substrate and a first cover slip. A second glass cover slip is removably mounted onto the first cover slip on the opposite side of the first cover slip to the substrate, a specimen to be examined being positioned between the two cover slips and adjacent to the RF coil. The specimen on the slide can be examined using conventional optical microscopy and then placed in an NMR apparatus and imaged or spectroscopic information obtained, using the optical picture as a guide to particular areas of interest. The slide is mounted onto a plastic holder which forms part of an NMR probe and is accurately positioned in a defined position with the NMR apparatus. As such, the sample mount described does not permit simultaneous optical imaging and NMR signal analysis as the sample mount must be transferred between optical and NMR apparatus and a previously obtained optical picture relied upon.

It would be advantageous to be able to perform optical microscopy on a sample at the same time as performing NMR or ESR signal acquisition from the sample. It would also be advantageous to provide NMR or ESR signal acquisition apparatus that can conveniently be integrated with existing optical microscopy equipment.

It is an object of the present invention to provide means for enabling optical microscopy at the same time as facilitating NMR or ESR signal acquisition, without requiring relocation of a sample between different pieces of equipment. It is a further object of the present invention to provide an NMR or ESR signal acquisition apparatus that can be integrated with, and/or removably attached to, a conventional optical microscope.

Some or all of the above objects are achieved by embodiments of the present invention.

According to one aspect, the present invention provides a sample mount for enabling simultaneous optical imaging of, and NMR or ESR signal acquisition from, a specimen thereon, the sample mount comprising a platform having: a base for being received onto an optical microscope stage; a first magnet supported thereon for providing a static magnetic field; an RF coil; and a specimen support structure disposed external to the first magnet and the RF coil.

According to another aspect, the present invention provides apparatus for attachment to an optical microscope for enabling simultaneous imaging of, and NMR or ESR signal acquisition from, a specimen disposed on the microscope stage, the apparatus comprising: a carrier for releasable attachment to a lens housing of the microscope, the carrier comprising an axial aperture therethrough for receiving the microscope lens housing; a first magnet supported on the carrier for providing a static magnetic field; and an RF coil supported on the carrier; the apparatus being configured such that, when the apparatus is attached to the lens housing of the microscope, the first magnet and RF coil define an NMR or ESR signal acquisition volume external to the apparatus and on the optical axis in a plane coincident with a focal plane of the microscope lens.

According to another aspect, the present invention provides apparatus for attachment to an optical microscope for enabling simultaneous imaging of, and NMR or ESR signal acquisition from, a specimen disposed on the microscope stage, the apparatus comprising: a carrier adapted for coupling to a vacant objective port of the optical microscope; an objective lens supported on the carrier and positioned to form part of an optical axis of the microscope; a first magnet supported on the carrier for providing a static magnetic field; and an RF coil supported on the carrier; the apparatus being configured such that, when the apparatus is attached to the objective port of the microscope, the first magnet and RF coil define an NMR or ESR signal acquisition volume external to the apparatus and on the optical axis in a plane coincident with a focal plane of the objective lens. According to another aspect, the present invention provides an optical microscope comprising: a lens housing comprising an objective lens defining an optical axis; a stage axially separated from the objective lens along the optical axis, for receiving a specimen for optical examination through the objective lens; and a detachable NMR or ESR signal acquisition module disposed on the optical microscope and adapted to generate an NMR or ESR signal acquisition volume between the objective lens and the stage external to the module so as to allow lateral access to the signal acquisition volume.

According to another aspect, the present invention provides a sample mount for enabling simultaneous optical analysis of, and NMR or ESR signal acquisition from, a specimen thereon, the sample mount comprising a platform for being received onto or coupling to an optical analysis device; a first magnet supported on the platform for providing a static magnetic field; an RF coil; and a specimen support structure disposed external to the first magnet and the RF coil.

Embodiments of the present invention will now be described by way of example and with reference to the accompanying drawings in which: Figure 1 shows a front view of a microscope and NMR / ESR sample mount;

Figure 2 shows a more detailed front view of a part of the microscope and the NMR / ESR sample mount of figure 1 ;

Figure 3 shows a plan view of the sample mount of figure 2;

Figure 4 shows a front view of a microscope and NMR / ESR signal acquisition apparatus attached thereto;

Figure 5 shows a more detailed front view of a part of the microscope and the NMR / ESR signal acquisition apparatus of figure 4;

Figure 6 shows a plan view of the NMR / ESR signal acquisition apparatus of figure 5; Figure 7 shows a front view of an alternative NMR / ESR sample mount similar to that shown in figure 2;

Figure 8 shows a plan view of the sample mount of figure 7;

Figure 9 shows a front view of an alternative NMR / ESR signal acquisition apparatus similar to that shown in figure 5; Figure 10 shows a plan view of the NMR / ESR signal acquisition apparatus of figure 9;

Figure 11 shows a side elevation view of a spectrometer and NMR / ESR sample mount; Figure 12 is an end view of the NMR / ESR sample mount of figure 11 ; and

Figure 13 is a plan view of the NMR / ESR sample mount of figure 11.

Throughout the present specification, the descriptors relating to relative orientation and position, such as "top", "bottom", "upper", "lower", "horizontal", "vertical", "left", "right", "up", "down", "front", "back", as well as any adjective and adverb derivatives thereof, are used in the sense of the orientation in normal use as presented in the drawings. However, such descriptors are not intended to be in any way limiting to an intended use of the described or claimed invention.

Referring to figure 1 , there is shown an exemplary sample mount 10 for enabling simultaneous optical imaging of, and NMR or ESR signal acquisition from, a specimen thereon. A conventional microscope 1 has a base 2, support 3 and optics 4. The optics 4 include an eyepiece arrangement 5 and objective lens turret 6 in conventional fashion. The microscope 1 includes a moveable specimen stage 7 which is preferably drivable in the x and y directions (i.e. orthogonal to the optical axis of the microscope, shown as the vertical or z-axis) using a conventional micromanipulator arrangement. The specimen stage 7 is also moveable relative to the optics 4 along the optical axis (i.e. vertical as shown) using conventional focus adjustment controls.

Attached to the microscope stage 7 is a sample mount 10 which can be placed on or affixed to the stage 7. With reference to figure 2, the sample mount 10 comprises a planar base 11 and a planar specimen support plate 12 maintained in substantially parallel spaced-apart relationship by spacers 13 and/or front, back and/or side walls 14. Disposed within a cavity 15 defined by the base 11 and specimen support plate 12 is a permanent static magnet 16 and an RF coil 17 suitable for NMR or ESR signal acquisition from a specimen position 18 disposed on the specimen support plate 12.

Figure 3 shows a perspective plan view of the sample mount 10 illustrating the planar base 11 , the specimen support plate 12, spacers 13 and front, back and side walls 14. The spacers 13 are preferably hollow cylindrical spacers coincident with holes 20, 21 in the specimen support plate 12 and base 11 respectively, for fixing the component parts together. Figure 3 also shows the permanent magnet 16 and the RF coil 17. The permanent magnet 16 and RF coil 17 are preferably respectively bonded onto the base 11 and specimen support plate 12 although any suitable means for disposing these elements in position within the sample mount 10 may be used. Electrical leads 22 emerge from a lateral edge 23 of the sample mount 10 for connection to a suitable NMR / ESR signal acquisition apparatus (not shown). The RF coil 17 may generally be formed of copper loops or other electrically conductive elements embedded in, or attached to, an insulator such as an extruded acrylic plate forming the support plate 12. Preferably, the conductive elements of the RF coil are disposed on an underside of the specimen support plate.

The sample mount 10 of figures 1 to 3 effectively provides a platform suitable for positioning a conventional specimen slide (not shown) on top of the specimen support plate 12 on the optical axis of the microscope 1 , so that the specimen also resides in a specimen position 18 within an NMR / ESR signal acquisition volume, i.e. within range of the requisite magnetic fields generated by the static magnet 16 and RF coil 17 suitable for conducting NMR or ESR measurements. It is to be understood that the RF coil 17 provides a means for receiving NMR / ESR signals from a sample within the signal acquisition volume, which signals may also have been induced by the same RF coil 17 or by another excitation source. In other words, the RF coil preferably acts as a means for transmitting and receiving electromagnetic radiation at a frequency suitable for excitation and detection from the sample. In the preferred arrangement shown, the NMR / ESR components effectively define an "external NMR" or "unilateral NMR" apparatus, i.e. the signal acquisition volume and specimen position are outside the magnet 16, outside the coil 17 and outside the sample mount 10. In this preferred arrangement, full lateral access to the specimen position 18 is possible in any x-y direction (i.e. horizontal or parallel to the plane of the specimen support plate). This permits insertion and removal of a specimen slide in conventional manner and also allows interaction with the specimen under examination using, for example, tweezers or capillaries for specimen manipulation, e.g. to deliver contrast agents etc. This interaction can take place at the same time as both optical and NMR / ESR examination.

Preferably, the sample mount 10 provides an optical aperture 25 passing therethrough coincident with the optical axis of the microscope 1. The optical aperture 25, in the arrangement of figures 1 to 3, is provided by use of a transparent base 11 and a transparent support plate 12, a hollow cylindrical static magnet 16 and an RF coil 17 disposed around the optical aperture 25 but not occluding it. The expression "optical aperture" is used to indicate that light of at least selected frequencies is able to pass through the sample mount 10 from underneath it to the specimen position 18 on top of it in order to illuminate the specimen from below in a manner commonly used in optical microscopy. The optical aperture 25 could also be formed by using holes in the base 11 and support plate 12 rather than relying on inherent optical transmissivity of the top and bottom plates 12, 11.

Numerous modifications to the sample mount 10 of figures 1 to 3 are possible. The static magnet 16 could be a permanent magnet or an electromagnet. The static magnet could comprise several permanent magnets or electromagnets. Any shape of static magnet 16 (or magnets) and/or RF coil 17 can be provided suitable for generating appropriate magnetic fields in the specimen position 18. A toroidal magnet is another such example. One or more gradient coils (not shown) may be integrated into the sample mount 10 for providing magnetic field gradients in one or more of the x, y and z directions. One or more shimming coils (not shown) or shimming permanent magnets (not shown) may be incorporated into the sample mount 10. The base 11 is preferably planar as shown for convenient placement on a planar microscope stage 7, but other forms or shapes of base can be contemplated for mounting onto a suitable platform provided by the microscope. For example, the base may be provided simply by a set of legs or pins depending downwardly from the support plate 12, with all NMR / ESR components disposed on the underside of the support plate 12. Any suitable mechanism for enabling attachment to and detachment from the microscope specimen stage 7 may be provided. This may be by screws or bolts (not shown) through the holes 20, 21 in the sample mount 10. Spring clips depending downwardly from the peripheral edges of the sample mount 10 for clipping around and under the microscope stage 7 may be provided. The sample mount 10 may be formed from a solid block of generally non-conductive and generally non-magnetic material that defines the base 11 , specimen support plate 12, spacers 13, side walls 14 and cavity 15. In such an arrangement, the cavity is of course generally filled with the non-conductive and non-magnetic material and may have holes formed therein in place of the spacers 13 in order to provide fixing points for coupling the sample mount 10 to a microscope stage 7. The permanent magnet and RF coil arrangements may be embedded into the solid block, e.g. in separate cavities or surface channels. In this arrangement, the optical aperture 25 could also be formed by using a hole through the block or rely on inherent optical transmissivity of the block.

Turning now to figure 4, an alternative apparatus 40 for attachment to an optical microscope 1 for enabling simultaneous imaging of, and NMR or ESR signal acquisition from, a specimen disposed on a microscope stage 7 is shown. In this apparatus 40, the existing microscope stage 7 is used for direct placement of a specimen slide 30 in conventional manner. The NMR / ESR apparatus 40 is attached to an objective lens housing 31 of the microscope 1. As shown in figure 5, the apparatus 40 comprises a carrier or housing 41 having an axial aperture 42 therethrough which receives the objective iens housing 31 of the microscope 1. The apparatus 40 is preferably provided with a means for releasable attachment to the lens housing 31 , for example by a friction fit using elastomeric seals (not shown) within the axial aperture 42 or a suitable clip arrangement (not shown). The carrier or housing 41 supports a static magnet 16 and an RF coil 17 in a similar manner to the arrangement of figures 1 to 3. The magnet 16 and RF coil 17 define an NMR or ESR signal acquisition volume 48 immediately external to the apparatus 40, i.e. below the lower surface 43 of the carrier or housing 41 and on the optical axis of the microscope 1.

The NMR / ESR signal acquisition volume 48 extends sufficiently far from the lower surface 43 of the apparatus 40 (i.e. along the z-axis) such that it encompasses the focal plane of the objective lens of the microscope 1. It will be understood that when a specimen slide 30 is loaded onto the microscope stage 7 and the optics 4 are lowered (or the stage raised) to bring the focal plane of the objective lens into coincidence with a specimen on the slide 30, the NMR / ESR signal acquisition volume 48 will also be brought into coincidence with the specimen on the slide 30. In this way, NMR / ESR signal acquisition can be obtained simultaneous with optical inspection of the specimen and an NMR / ESR selected slice in the x-y plane will remain matched to the optical focal plane, the position of which can be optimised by the user using conventional controls on the microscope.

Figure 6 shows a perspective plan view of the apparatus 40 illustrating the carrier or housing 41 , front, back and side walls 45 thereof and the axial aperture 42 coincident with the optical axis of the microscope 1. Figure 6 also shows the permanent magnet 16 and the RF coil 17. The permanent magnet 16 and RF coil 17 are preferably mounted to the carrier 41 around the axial aperture although any suitable means for disposing these elements in position within the apparatus 40 may be used. Electrical leads 22 emerge from a lateral (e.g. front) edge 44 of the apparatus 40 for connection to a suitable NMR / ESR signal acquisition apparatus (not shown).

The apparatus 40 of figures 4 to 6 effectively provides an attachment for a conventional microscope 1 that provides an external NMR / ESR signal acquisition volume 48 in the optical axis of the microscope 1 , and at a focal plane of the objective lens. In this way, a specimen under optical examination resides within the NMR / ESR signal acquisition volume 48, i.e. within range of the requisite magnetic fields generated by the static magnet 16 and RF coil 17 suitable for conducting NMR or ESR measurements. The NMR / ESR components effectively define an "external NMR" or "unilateral NMR" apparatus, i.e. the signal acquisition volume and specimen position are outside the magnet 16, outside the coil 17 and outside the apparatus housing 41 so that they do not interfere with the normal working of the microscope and full lateral access to the specimen on slide 30 is possible in any x-y direction (i.e. parallel to the plane of the microscope stage 7). This permits insertion and removal of a specimen slide 30 in conventional manner and also allows interaction with the specimen on the slide under examination using, for example, tweezers or capillaries for specimen manipulation, e.g. to deliver contrast agents etc. This interaction can take place at the same time as both optical and NMR / ESR examination.

Numerous modifications to the apparatus 40 of figures 4 to 6 are possible. The static magnet 16 could be a permanent magnet or an electromagnet. The static magnet could comprise several permanent magnets or electromagnets. Any shape of static magnet

16 (or magnets) and/or RF coil 17 can be provided suitable for generating appropriate magnetic fields in the specimen position 18, i.e. on the optical axis and at the focal plane of the objective lens. One or more shimming coils (not shown) or shimming permanent magnets (not shown) may be incorporated into the carrier or housing 41. The distance from the lower surface 43 of the carrier or housing 41 at which the signal acquisition volume 48 is defined will depend on the distance of the focal plane of microscope objective lens from the end of the lens housing 31 (or the lens itself if this protrudes). In a typical microscope, this distance ranges from contact (zero distance) to about 5 cm. One or more gradient coiis (not shown) may be integrated into the apparatus 40 for providing magnetic field gradients in one or more of the x, y and z directions. The lower surface 43 of the apparatus preferably does not extend below the lowest level of the objective lens or lens housing 31 and is preferably planar or convex-downwards so as not to interfere with the specimen or planar microscope stage 7. Other forms or shapes of apparatus 40 can be contemplated for specific arrangements of microscope. Any suitable mechanism for enabling attachment to and detachment from the microscope lens housing 31 may be provided.

In another arrangement, the apparatus 40 could incorporate the objective lens or lenses itself. In this case, the apparatus may be configured to be installed into a vacant objective port on the microscope, e.g. a position within a rotating multi-position turret 6 from which an existing microscope objective lens housing 31 has been removed. In such an arrangement, the carrier or housing 41 also supports an objective lens of suitable optical performance and in a position such that its focal plane is coincident with an NMR or ESR signal acquisition volume defined by the magnet and RF coil.

As stated previously, the static magnet 16 or magnets and RF coils 17 in both arrangements of figures 1 to 6 may be of any suitable form to provide the required magnetic fields at the specimen position. In figures 7 and 8 an alternative sample mount 70 similar to the sample mount 10 shown in figures 1 to 3 is provided with pillar magnets 74 disposed around a circular RF coil 73. In figures 9 and 10 an alternative apparatus 90 similar to the apparatus 40 shown in figures 4 to 6 is provided with pillar magnets 94 disposed around a circular RF coil 93. The configuration of pillar magnets disposed around a circular RF coil is a particularly effective way of achieving a unilateral NMR transceiver with an active NMR volume in the shape of a thin flat square, useful for most samples examined under optical microscopy. See for example J Perlo: "Profiles with microscopic resolution by single sided NMR"; J. Magn. Reson. 176 (2005) 64-70.

All of the arrangements described in connection with figures 1 to 10 can effectively provide a detachable NMR or ESR signal acquisition module disposed on an optical microscope and adapted to generate an NMR or ESR signal acquisition volume between an objective lens of the microscope and a support surface for a specimen slide external to the module in such a way that lateral access to the signal acquisition is maintained and NMR / ESR signal acquisition is possible even during optical analysis of a specimen.

As shown, the detachable NMR or ESR signal acquisition module can be attached to a lens housing 31 of a conventional microscope 1 or to the specimen stage 7 of a conventional microscope 1. Full optical functionality of the conventional microscope can be maintained during NMR / ESR signal acquisition. It will be understood that the apparatus described could readily be adapted to other forms of optical microscopy equipment where an image gathering element (e.g. an opto-electronic sensing element such as a charge coupled device, possibly in combination with focusing optics) is disposed adjacent or proximal to a specimen to be examined. The NMR / ESR signal acquisition apparatus may be adapted for use with any such optical microscopy equipment to provide an NMR / ESR signal acquisition volume coincident with an image plane where the specimen lies. As used herein, the expressions 'microscope' and Optical imaging' are intended to encompass spectrometers where a sample or portion thereof is optically analysed by placing it in the path of an analysis beam and collecting light therefrom.

Referring to figure 11 , there is shown an exemplary sample mount 110 for enabling simultaneous spectroscopic analysis of, and NMR or ESR signal acquisition from, a specimen therein. A conventional spectroscopy apparatus 100 includes an input optical path (e.g. a focusing lens 101) and an output optical path (e.g. a collimating lens 102). The apparatus 100 includes a moveable specimen stage 103 which is preferably drivable in the x, y and z directions using a conventional micromanipulator arrangement. A sample can thus be manipulated into position on an optical axis 111 defined by the input and output optical paths for spectroscopic measurements on the whole or specific parts of the sample. The specimen stage 103 is also preferably moveable along the optical axis for positioning at appropriate focal points of the lenses 101 , 102.

The sample mount 110 can be placed on or affixed to the stage 103. The sample mount 1 10 comprises a planar base 104 and a cavity 105 for receiving a removable specimen support structure or vessel 107. The cavity 105 may be defined by suitable side walls. Also disposed within the sample mount 110 is a permanent static magnet or a pair of permanent static magnets 106 and an RF coil 108 suitable for NMR or ESR signal acquisition from a specimen position 109 disposed within the cavity 105. Figure 12 shows an end view of the sample mount 110 and figure 13 shows a plan view of the sample mount 110, illustrating the permanent magnets 106, the RF coil 108 and the specimen support structure or vessel 107. The permanent magnet 106 and RF coil 108 are preferably respectively bonded onto the base 104. Electrical leads 122 emerge from an edge of the sample mount 110 for connection to a suitable NMR / ESR signal acquisition apparatus (not shown). The RF coil 108 and magnets 106 may otherwise be formed in similar manner to the examples described with reference to figures 1 to 10.

The sample mount 110 of figures 11 to 13 effectively provides a platform suitable for positioning a conventional specimen slide or support vessel on top of the specimen stage 103 on the optical axis of the spectroscope 100, so that the specimen also resides in a specimen position 109 within an NMR / ESR signal acquisition volume, i.e. within range of the requisite magnetic fields generated by the static magnets 106 and RF coil 108 suitable for conducting NMR or ESR measurements. It is to be understood that the RF coil 108 provides a means for receiving NMR / ESR signals from a sample within the signal acquisition volume, which signals may also have been induced by the same RF coil 108 or by another excitation source. In other words, the RF coil preferably acts as a means for transmitting and receiving electromagnetic radiation at a frequency suitable for excitation and detection from the sample. Lateral access to the specimen in structure or vessel 107 is possible from the upward direction as viewed in figure 11. This permits insertion and removal of a specimen and also allows interaction with the specimen at the same time as both optical and NMR / ESR examination.

Other modifications to the sample mount 110 of figures 11 to 13 are possible, corresponding where appropriate to those discussed in connection with figures 1 to 10. For example, the sample mount 110 could be adapted to be coupled to the spectroscope lens 101 or 102.

Thus, in a general sense, the invention provides a sample mount for enabling simultaneous optical analysis of, and NMR or ESR signal acquisition from, a specimen thereon, the sample mount comprising a platform for being received onto or coupling to an optical analysis device stage or lens housing; a first magnet supported on the platform for providing a static magnetic field; an RF coil; and a specimen support structure disposed external to the first magnet and the RF coil. The apparatus described in connection with figures 1 to 13 can be connected to a conventional NMR console for NMR relaxivity measurements, magnetic resonance (MR) imaging, one-dimensional or multi-dimensional NMR spectroscopy measurements or ESR measurements, etc.

The apparatus described allows the non-invasive collection of two independent sets of information, retrieved simultaneously from a specimen, and the monitoring of their time course. For example, spatially resolved optical information (the contrast of which may or may not be enhanced by staining agents) may be gathered simultaneously with NMR / ESR information, which may or may not be enhanced using contrast agents. Typical specimens or samples of interest are live cell cultures, as they can be monitored without interfering with the biological processes occurring within them.

The two sets of information provide the user with superior monitoring ability and understanding of processes of interest. A process of interest in the cell culture could be the development of a disease, its reduction due to a healing process, cell death counting, the dynamics of the uptake of a contrast agent or other chemical by the cells etc.

The NMR / ESR information may or may not be spatially resolved. If it is spatially resolved, the MR image contrast may or may not be enhanced by using NMR contrast agents. The NMR / ESR information can be used for spectroscopy to reveal molecular distributions and to follow their dynamics.

In addition to microscopes using visible light, infrared or ultraviolet light may be used and the expression "optical" as used herein is intended to encompass all such forms of microscopy. Partially coherent light could be used as in optical coherence tomography. Additionally, the apparatus described herein can be configured to be suitable for attachment to a number of different devices by means of a simple modification to the securing mechanism. This would facilitate the collection of NMR or ESR signals from several pieces of equipment.

The various configurations of apparatus described herein each provide some or all of the following features and advantages: (i) an open geometry system allowing for lateral access to a specimen and lighting of the specimen, (ιι) optical microscopy combined with unilateral NMR / ESR, (HI) the ability to retrofit NMR / ESR signal acquisition apparatus to existing conventional microscopes, (ιv) a full range of NMR measurements simultaneous with optical measurements such as imaging, spectroscopy, multi-nuclear NMR etc, (v) optical measurements other than just optical microscopy, such as fluorescence, infrared, Raman spectroscopy, (vι) the ability to perform NMR / ESR analysis without affecting the performance of a conventional optical microscope

The apparatus may be used in both medical and research sectors, e g in histology and haematology departments in medical institutions Simultaneous testing of a sample with NMR and optical microscopy could highlight areas such as abnormal cells in tissues, particularly if the sample is first treated with a suitable contrast agent The benefits could be enhanced medical diagnostic (hospital environment) and monitoring / understanding of in-vivo cellular biological / physiological processes

Other embodiments are intentionally within the scope of the accompanying claims

Claims

1. A sample mount for enabling simultaneous optical imaging of, and NMR or ESR signal acquisition from, a specimen thereon, the sample mount comprising a platform having: a base for being received onto an optical microscope stage; a first magnet supported thereon for providing a static magnetic field; an RF coil; and a specimen support structure disposed external to the first magnet and the RF coil.

2. The sample mount of claim 1 further including means for attachment to and detachment from a planar stage of an optical microscope.

3. The sample mount of claim 1 further including an optical aperture passing through the base, the first magnet, the RF coil and the specimen support structure.

4. The sample mount of claim 1 further including one or more gradient coils disposed on the platform.

5. The sample mount of claim 1 in which the base comprises a planar base, and the specimen support structure comprises a planar member disposed substantially parallel to the planar base, the first magnet and RF coil being disposed between the planar base and the specimen support structure.

6. The sample mount of claim 5 in which the first magnet comprises a cylindrical or toroidal magnet disposed between the planar base and the specimen support structure, and the RF coil comprises a conductive element disposed on or adjacent the specimen support structure, both having a central axis within an optical aperture passing through the base, the first magnet, the RF coil and the specimen support structure.

7. The sample mount of claim 2 in which the means for attachment to and detachment from a planar stage of an optical microscope comprises a clip mechanism.

8. Apparatus for attachment to an optical microscope for enabling simultaneous imaging of, and NMR or ESR signal acquisition from, a specimen disposed on the microscope stage, the apparatus comprising: a carrier for releasable attachment to a lens housing of the microscope, the carrier comprising an axial aperture therethrough for receiving the microscope lens housing; a first magnet supported on the carrier for providing a static magnetic field; and an RF coil supported on the carrier; the apparatus being configured such that, when the apparatus is attached to the lens housing of the microscope, the first magnet and RF coil define an NMR or ESR signal acquisition volume external to the apparatus and on the optical axis in a plane coincident with a focal plane of the microscope lens.

9. The apparatus of claim 8 further including one or more gradient coils disposed on the carrier.

10. The apparatus of claim 8 in which the first magnet and RF coil are disposed around the axial aperture of the carrier.

1 1. An optical microscope comprising: a lens housing comprising an objective lens defining an optical axis; a stage axially separated from the objective lens along the optical axis, for receiving a specimen for optical examination through the objective lens; and a detachable NMR or ESR signal acquisition module disposed on the optical microscope and adapted to generate an NMR or ESR signal acquisition volume between the objective lens and the stage external to the module so as to allow lateral access to the signal acquisition volume.

12. The optical microscope of claim 11 in which the signal acquisition module is attached to the lens housing.

13. The optical microscope of claim 12 in which the signal acquisition module encircles the lens housing about the optical axis but does not extend along the optical axis past an objective end of the lens housing.

14. The optical microscope of claim 11 in which the signal acquisition module is attached to the stage and defines a specimen support surface on an upper surface thereof.

15. The optical microscope of claim 14 in which the signal acquisition module further includes an optical aperture passing therethrough along the optical axis to permit illumination of a specimen on the specimen support surface from the opposite side of the specimen support surface to the objective lens.

16. Apparatus for attachment to an optical microscope for enabling simultaneous imaging of, and NMR or ESR signal acquisition from, a specimen disposed on the microscope stage, the apparatus comprising: a carrier adapted for coupling to a vacant objective port of the optical microscope; an objective lens supported on the carrier and positioned to form part of an optical axis of the microscope; a first magnet supported on the carrier for providing a static magnetic field; and an RF coil supported on the carrier; the apparatus being configured such that, when the apparatus is attached to the objective port of the microscope, the first magnet and RF coil define an NMR or ESR signal acquisition volume external to the apparatus and on the optical axis in a plane coincident with a focal plane of the objective lens.

17. Apparatus substantially as described herein with reference to the accompanying drawings.