Tools
9 articles
Ceramic and Sapphire Knives
Care and Maintainence for your Ceramic & Sapphire Knives Ceramic and sapphire micro‐dissection knives (non‐metallic scalpels) were developed during the 1970s, subsequent to Fernadez Moran's invention of the first diamond knives (~1965) for ultramicrotomy and viewing specimens in electron microscopes. These diamond knives are used to produce flawless sections 60nm thick. This technology paved the way for hand‐held ceramic and sapphire micro‐knives for finest dissection and microsurgery. These knives were first used in ophthalmology, but they have proven useful in cosmetic surgery and microsurgery as well as in the biomedical sciences, whenever finest cuts, without reactive metal ions, and least adjacent cell damage are required. Ceramic versus sapphire knives: Our ceramic knives are produced from black, sintered zirconium dioxide. This material is of similar hardness to sapphire, but it is not transparent and more flexible. Both the ceramic and sapphire blades are very hard, and considering how fine and acute the cutting edges are, they are surprisingly durable. The ability to see through a knife sometimes is an advantage, and the sapphires are glass‐clear. Sharpened edges usually reflect light away and so appear black with either blade. However, sapphire knives, when used near horizontal (the 'round blades' are particularly suitable) are excellent for cutting in that plane with perfect vision of structures below the knife. Handling, cleaning and sterilising: Diamond (Mohs hardness scale 10), sapphire (9) and ceramic zirconia (8.5) are among the hardest substances known. Harder materials keep a sharp edge better. However, such hard materials may be brittle and lateral pressure on the knife can snap the stone. These knives must be handled with care and the cutting edge should only ever gently touch tissues to be cut and no other solid ‐ don't test the sharpness of our knives with a finger! If a blade is perfectly handled is can give years of good service, rough, but non 'fatal' handling of a knife will fracture microscopic particles off the knife's edges resulting in bluntness well before time. After use rinse the knife under running water. If serious contamination occurred, the knife may be soaked in weak household detergent solution and placed in an ultrasonic bath for 2 minutes. Rinse in tap and then distilled water at least 3 times. The knives may be wet autoclaved . During these procedures make sure the actual knife never touches anything solid. To prolong the life of this edge, never touch it with any solid object. Use the following guidelines: Avoid touching the edge when inserting or removing the knife. Don't contact the edge with any tools when operating your microtome. Safely store the blade in its box when not in use. The best sections come from a clean environment. Keep your knife clean by: Using clean water, buffers or reagents in your microtome. Rinsing and wiping the reservoir and stage of your microtome between use. Preventing sections from drying on the knife. Sectioning problems usually come in three forms: Chatter, compression and knife marks. As a general rule, vibratome sectioning with a sapphire knife is done with high amplitude, slow approach speed and a knife angle setting of about 23°. You should spend some time learning the effects that changes in these operating parameters have on section quality. Chatter is the result of vibration during cutting and appears as regularly spaced thick and thin lines on the section perpendicular to the direction of cut. Too low a clearance angle, too fast an approach and too hard a specimen are several causes of chatter. Compression is a crushing of the section as it is cut, resulting in a section that is shorter than the original block face and thicker than the microtome setting. Too high a clearance, too soft a specimen and a dull knife can cause compression. Knife marks are lines that appear on the section parallel to the direction of cut. A dirty or damaged knife edge causes knife marks. If you have sectioning problems, especially knife marks, a dirty knife may be one of the causes. Clean the edge using a Diamond Knife Cleaning Tool, Product No. 122-10, following the steps on next page. This PVA spear tip wicks liquids instantaneously to make a safe and sure cleaning tool. The spear does not expand with alcohol so it can be used in its rigid form by dipping in reagent alcohol only: or it can be expanded using clean water and then dipped in reagent alcohol. The expanded spear can be allowed to dry and stiffen, then dipped in reagent alcohol. Dipping the expanded spear in alcohol can speed up the drying time. Premoisten the spear with clean water and dry if desired to achieve the desired shape and stiffness. Dip the spear in reagent alcohol. Gently drag the tip of the spear along the side of the knife, parallel to the edge. Repeating on the other side of the blade and allowing to air dry. Alternatively view the knife edge under a dissecting microscope and press the spear tip against the edge of the knife as though to split the tip. DO NOT USE DRY. Dip an expanded and dried spear into reagent alcohol and shake or blot on filter paper to remove excess. Using little force, wipe the spear tip parallel to the cutting edge, never obliquely or at a right angle. Move across the entire length of the knife edge, then use a fresh part of the spear and repeat in the opposite direction. ProSciTech's black ceramic zirconia scalpels Sometimes called "black diamond" scalpels because they are hard and durable, but unlike diamond, these scalpels have a modicum of flexibility which extends their life on occasions. All blades are made to most exacting standards; our photos are not retouched and demonstrate these knives' perfection. At the same time we are able to supply them at one‐third the price of similar scalpels. We don't offer a re‐sharpening service since, without even considering shipping and handling, our new scalpels are cheaper than resharpened scalpels from other suppliers. Oz and NZ customers may use our shopping cart or place an order by email or phone. Overseas customers please email enquiries ‐ we will then advise of shipping charges and produce an invoice, which can be paid via our secure link to the bank. All handles are made of titanium and the blades are retractable. Keep the open end free of obstructions when you push out the blade! Telling sapphire and ceramic zirconia blades apart without a label is easy: the ceramic zirconia is black and comes with a blue titanium handle; sapphire is glass‐clear and comes with a silver‐coloured titanium handle. Angled and large knives are in a larger diameter sheath. Blades All lancets are double edged, meaning the the underside and the upper side of the blade are sharpened to the edge and the profile is arrow shaped. Single edge blade = the upper side is sharpened to the edge, the underside is flat. Double edge blade = the underside and the upper side are sharpened, arrow shaped profile. Measurements given in the name of the knives are the width of the blade and the angle at which the tip is cut. The thickness of the blade is given in the text. Angled and straight refers to the mounting of the blade. Scope of Application: Ophthalmic, microsurgical, neurological, plastic surgery, urological, ENT surgical, fine dissections and microsurgery in the biomedical sciences. Physical & Chemical Characteristics of Sapphire Surgical Knives The sapphire knife provides a superb cut, far exceeding that of a finely honed steel knife. An incision made by a sapphire knife results in significantly less damage than from a conventional steel knife, and no metal particles are left behind in the tissue, so wounds heal faster with less scarring. High stability of physical and chemical properties, good biocompatibility, little effect on neural excitability, small astigmatism, neat incision, wounds healing faster with less scarring, non‐infiltration by acid and blood, corrosion resistance, effortless sterilisation. Physical & Chemical Characteristics of Nano‐Crystalloid Ceramic Zirconia Surgical Knives High hardness, density, sharpness and toughness Black blade, no reflection ensures good visualisation Good biocompatibility Non‐infiltration by acid and blood, corrosion resistance, effortless sterilisation. No metal particles left in the tissue Specifications Diamond Ceramic Zirconia Sapphire Stainless Steel Mohs hardness 10 8.5 9 6.5 Viscosity (Mpa/M) 6 10‐12 3‐4 Curvature 1200‐1600 300‐500 Frictional coefficient (Kr) 0.35 0.1 0.44 Sharpness 1000A 1000A 5000A Note: The dimensions in the diagrams are given in mm.
DiATOME Histo Diamond Knife
DiATOME the histo knife for light microscopy Applications: High quality diamonds guarantee perfect sections and a durable cutting edge Easy wetting cutting edge Optimised serial sectioning Large boat for easy pick-up Knife type Knife angle Size Thickness range Boat type Application histo 45° 4.0mm 6.0mm 8.0mm 0.2-2mm histo boat Sectioning biological and industrial materials specimens for optical microscopy histo Jumbo 45° 6.0mm 8.0mm 0.2-2 Jumbo boat Large boat for serial sectioning histo cryo (dry) 45° 4.0mm 6.0mm 8.0mm 0.2-2 histo holder Sectioning biological and materials specimens for optical microscopy histo cryo (wet) 45° 4.0mm 6.0mm 8.0mm 0.2-2 Small histo boat Wet sectioning of polymers (with DMSO/water mixture) Histo knives The knife is designed for the sectioning of hard and soft biological and industrial materials, non-embedded or embedded in methacrylate or epoxy resins. The Histo knife may be used on all ultramicrotomes and microtomes with a retraction of the specimen in the return phase. For the production of our Histo knives we use natural diamonds of highest quality. They guarantee the best quality and durability of the cutting edges. Some of the advantages of our Histo diamond knife compared with glass knives: Perfect sections, free of scores or compression Serial sections without knife change Thinner sections Extreme durability of the cutting edge No knife making procedure Lifetime guarantee Nondecalcifi ed rat bone. Scale: 35 mm = 100 μm. Daniel Studer, Anatomisches Institut, Bern. Histo Jumbo knives For 3D reconstruction it is imperative not to lose a single section (Ref. Blumer). The large Jumbo boat as well as the adhesive (Pattex compact by Henkel) applied to the side of the sample block increase the distinct advantages of our histo knives. Features: Easy production of section ribbons (0.5-2µm) No section loss No folding The same orientation of all sections Easy collection of section ribbons Multiple ribbons on one glass slide Perfect for immuno-histo-chemistry Eye of A. peroni: photographic sequence of some semithin sections of a complete serie through the eye. L = lens; RE = retina. Michael J. F. Blumer, Institut für Zoologie, Universität Wien. Reprinted from: Ribbons of semithin sections: an advanced method with a new type of diamond knife. Journal of Neuroscience Methods 120, pp. 11 – 16, 2002, with permission from Elsevier. Histo Cryo knives histo cryo knives are delivered with a boat for wet sectioning using a DMSO/water mixture or in triangular holders for dry sectioning , made of a special copper/nickel alloy, which guarantees the best heat/cold transmission. E. B. Hunziker, M. E. Müller, Institute for Biomechanics, University of Bern. Rabbit joint, calcified cartilage/bone. X760 References: O.L. Reymond: The «semi» diamond knife: a substitute for glass or conventional diamond knives in the ultramicrotomy of thin and semi-thin sections. Bas. Appl. Histochem. 30, pp. 487-494, 1986. M.J.F. Blumer, P. Gahleitner, T. Narzt, C. Handl, B. Ruthensteiner: Strips of semi-thin sections: an advanced method with a new type of diamond knife. Journal of Neuroscience Methods 120,pp. 11-16, 2002. Contact adress M.J.F. Blumer: michael.blumer@uibk.ac.at M.J.F. Blumer: Development of a unique eye: photoreceptors of the pelagic predator Atlanta peroni (Gastropoda, Heteropoda). Zoomorphology 119, pp. 81-91, 1996.
DiATOME Ultra Diamond Knife
DiATOME Ultra-Thin Diamond knives Applications: Highest quality diamonds and optimal crystal orientation guarantee perfect ultrathin sections and a durable cutting edge Section pick-up is facilitated as the boat is horizontal allowing the water to completely fill the boat all the way round A hydrophilic surface makes it easy to wet the cutting edge, even with low water level Knife type Knife angle Size Thickness range Boat type Application ultra 35° 35° 1.5mm 2.0mm 2.5mm 3.0mm 3.5mm 4.0mm 30–200nm Standard boat Soft industrial samples such as metals and polymers Hard and brittle samples such as semiconductors, superconducting oxides, nanocrystalline ceramics ultra semi 35° 3.0mm 50–500nm Standard boat Alternating sectioning ultrathin/semithin ultra AFM 35° 2.0mm 3.0mm 15–100nm Small boat Sample surfacing for AFM ultra 35° Jumbo 35° 2.0mm 3.0mm 50–200nm Jumbo boat Section series for 3D reconstruction, STEM ultra Maxi 35° 4.0mm 30–200nm Large boat Similar to ultra 35, features a larger boat. ultra sonic (with control unit) ultra sonic (knife only) 35° 3.0mm 4.0mm 3.0mm 4.0mm 15–100nm Special boat Compression-free sections Best structure preservation Biological and materials science specimens ultra sonic Maxi (with control unit) ultra sonic Maxi (knife only) 35° 3.0mm 4.0mm 3.0mm 4.0mm 30–150nm Special boat Compression-free sections Serial sectioning in biological applications ultra ats 35° 2.0mm 3.0mm 4.0mm 30–200nm Special boat Placing sections on Si wafers ultra 45° 45° 1.5mm 2.0mm 2.5mm 3.0mm 3.5mm 4.0mm 8.0mm 30–200nm Standard boat Routine sectioning of biological and materials science specimens ultra 45° Jumbo 45° 2.0mm 3.0mm 50–200nm Jumbo boat Section series for 3D reconstruction, STEM ultra 35° In 1989 considerably reduced compression, smoother section surfaces and improved structural preservation thanks to the use of our ultra 35° knives was demonstrated (J. C. Jésior, Scanning Microscopy Supplement 3, pp. 17 – 153, 1998). In the meantime, a large number of researchers have recognized the advantages of 35° knives, in particular for sectioning biological specimens of all kind, non-homogenous specimens, non-decalcified bone, dental material, etc. The ultra 35° knives are perfect for sectioning relatively soft materials research specimens including metals and polymers, as well as mixed specimens such as polymers filled with nanoparticles, brittle materials such as catalysts, crystals, semiconductors, etc (G. Mahon et al., Microscopy Research and Technique, Vol. 31, pp. 267 – 274, 1995, S. R. Glanvill, Microscopy Research and Technique, Vol. 31, pp. 275 – 284, 1995, P. Swab et al., Mat. Res. Soc. Symp. Proc. Vol. 115, pp. 229 – 234, 1989, P. Schubert-Bischoff et al., Microscopy and Microanalysis, proceedings, page 359, 1997). The ultra 35° knife has demonstrated its usefulness as a standard knife for the majority of applications in both biological and materials research. ultra sonic Thinner sections No compression Best structure preservation With correct setting of frequency and amplitude the sections become as long as the height of the sample. The patented ultra sonic knife allows the cutting of ultrathin sections free of compression (D. Studer et al., Journal of Microscopy, Vol. 197, pp. 94 – 100, 2000). We have tested the ultra sonic knife with the following samples: Biological samples in Epon, Araldite, EM Bed, etc. Biological samples in acrylic resins Lowicryl, LR White). Rigid polymers such as PS, PMMA, ABS, HIPS, modified PP, blends of various kinds. ultra sonic Maxi The ultra sonic Maxi is a new wider ultra sonic knife specifically for serial sectioning in biological applications. The knife comes in 3.0mm and 4.0mm sizes with 35° angle. Ultrathin sections without compression All embedding resins (Epoxies and Acrylates) The same control unit as for the ultra sonic usable Automatic setting of the resonance frequency Knife angle 35° Boat (inside 17 x 25 mm) made from titanium Easy wetting of the cutting edge ultra ats The ultra ats Diamond knife is perfect for placing sections on Si wafers to view under the SEM. The knife comes in 3.0mm size with 35° angle. Please see our Technical Data Sheet for an illustration showing the technique of placing sections on a wafer. ultra AFM Our ultra AFM knives are of the highest quality to ensure the increased quality requirements of AFM investigation. They produce extremely smooth sample surfaces and guarantee the best possible structure preservation. In order to achieve the best results for AFM investigation, only the highest quality diamond knives should be used (P. H. Vallotton et al., J. Biomater. Sci. Polymer Edn., Vol. 6, No. 7, pp. 609 – 620, 1994. N. Matzko et al., Journal of Structural Biology 146, pp. 334 – 343, 2004). ultra 45° Acknowledged as the appropriate knife angle for routine sectioning of both biological and materials research specimens, it represents a balanced compromise between section quality and durability. For the sectioning of a number of hard materials such as ceramics, semiconductors, oxides etc, with the use of the ultra 45° knife a longer service time may be expected. Kindly contact us and make use of our long years experience in all ultramicrotomy applications. ultra 45° Jumbo The ultra diamond knife is now available in Jumbo with 35° and 45° angles and in 2.0mm and 3.0mm sizes. These knives are well suited for serial sectioning for 3D reconstructions and STEM. References: J.C. Jésior: Use of low-angle diamond knives leads to improved ultrastructural preservation of ultrathin sections. Scanning Microscopy Supplement 3, pp. 17-153, 1989. Scanning Microscopy International, Chicago (AMF O'Hare) IL 6066 USA. L. Edelmann: Freeze-substitution and the preservation of diffusable ions. Journal of Microscopy, Vol. 161, pp. 217-228, 1991. G. Mahon and T. Malis: Ultramicrotomy of Nano-crystalline Materials. Microscopy Research and Technique, Vol. 31, pp. 267-274, 1995. S.R. Glanvill: Ultramicrotomy of Semiconductors and Related Materials. Microscopy Research and Technique, Vol. 31, pages 267-274, 1995. P. Swab abd R.E. Klinger: Preparation of multilayer coatings for cross-sectional Microanalysis by Ultramicrotomy. Mat. Res. Soc. Symp. Proc. Vol. 115, pages 229-234, 1989. P. Swab: Ultra-microscopy of Diamond Films for TEM Cross-Section Analysis. Microscopy Research and Technique, Vol. 31, pp. 308-310, 1995. C. Quintana: Ultramicrotomy for Cross-sections of Nanostructure. Micron Vol. 28, No. 3, pages 217-219, 1997. Y. Maniette: Microtomy, a convenient method for preparing TEM samples in ceramic science. Journal of Material Science Letters 9, pages 48-50, 1990. P. Schubert-Bischoff and T. Krist: Fast cross-sectioning technique for thin films by Ultramicrotomy. Microscopy and Microanalysis, proceedings, page 359, 1997. J.L. Guerquin-Kern, T.D. Wu, C. Quintana, A. Croisy: Progress in analytical imaging of the cell by dynamic secondary ion mass spectroscopy (SIMS microscopy). BBA 1724, pp. 228-238, 2005.
DiATOME Ultra Sonic Oscillating Diamond Knife
DiATOME Ultra Sonic for compression-Free Ultra-Thin Sections For many years Diatome diamond knives have been used successfully for a wide range of room - and low temperature sectioning applications. Major advances in immunocytochemistry, the sectioning of frozen hydrated specimens, semithin sectioning for optical microscopy, as well as the sectioning of hard industrial samples have been realised using Diatome diamond knives. The development of the Static Line II ioniser enabled dry ultramicrotomy of Lowicryls and a considerable improvement in cryosectioning. Despite these innovations, until now, one major obstacle remained, preventing us from achieving perfect ultra-thin sections: "compression" which we define as the shortening of the section compared to the sample height. The amount of compression depends on various factors including: The wedge angle of the knife. The hardness of the sample. The interaction diamond surface / section surface. The section thickness The most critical factor is the wedge angle of the knife. It was shown that reducing the wedge angle results in a reduction of compression, hence better preservation of ultrastructure which allows a higher achievable resolution. However, the wedge angle may not be reduced ad infinitum. A further reduction results in a lower cutting edge quality and a considerably shorter life span. In cryo-ultramicrotomy, compression, expressed as a percentage, was found almost equal to the wedge angle in degrees: 45° knife 40-50% 35° knife 30-40% An oscillating knife for low temperature applications is in preparation. In room temperature ultramicrotomy, we have found the following compression factors (section thickness 50nm): 10-20% for Epon, Araldite, EM-Bed, and other epoxy resins. 12-24% for Lowicryl K4M. 10-17% for Spurr's (hard grade). 8-13% for LR White (hard grade). These limitations have stimulated our efforts to develop the oscillating knife. It has been shown that compression in frozen-hydrated sections is the limiting factor for successful electron topographic analysis. Cryo sections from vitrified samples without compression were achieved by A. Al-Amoudi, LAU, University of Lausanne. Benefits: Thinner sections No compression Better structural preservation The DIATOME ultra sonic, the oscillating diamond knife for room temperature ultramicrotomy. It was developed in collaboration with Dr Daniel Studer, Lab. of Anatomy, University of Berne. A piezo actuator produces an oscillation of the knife at a desired frequency and amplitude, parallel with the cutting edge. A depression in the foot of the knife allows the oscillation parallel to the cutting edge. The depression is rigid in the north/south direction and guarantees stability in the cutting direction. The new knife produces ultrathin sections almost free of compression.The sections become thinner at the same thickness setting: since the volume of the section remains the same, the increased length leads to a decrease in thickness. The theoretical considerations and first results of this invention were presented in the Journal of Microscopy. Results with polymers using the oscillating knife were shown at the M&M 2002 meeting in Quebec. We have tested the oscillating knife with the following samples: Biological samples in Epon, Araldite, EM Bed, etc. Biological samples in acrylic resins (Lowicryls, LR White). Rigid polymers such as PS, PMMA, ABS, HIPS, modified PP, etc. Peripheral nerve (rat) Heart (rat) Human keratinocyte ABS Impact modified PP Specifications: Knife angle: 35° Knife cutting range: 10-80nm Knife cutting edge length: 3.0mm Control Unit: Frequency: 25-45kHz, or automatic setting of the resonance Amplitude: variable (Voltage 0-30V) Mains voltage: 230V, 110V Angle Size Cutting Range New Knife wControl Unit Resharpen 35° 3mm 10-80nm Available Available Handling Sample preparation Trim the sample with a trim 45 or a trim 20 diamond blade. The sample width should be a maximum of 0.5 mm. Measuring the sample height With the use of an eyepiece graticule in one of the stereomicroscope oculars (graticule 10450336 for the Leica M80). Sample block (fixed in the sample holder), is mounted in the trimming plate. Measure the height with the graticule. Ultramicrotome Settings Set the clearance angle to 6° as shown on the guarantee card. Set the desired section thickness. Set the sectioning speed (0.4 – 0.6 mm/sec) Tighten all set screws. Installing the knife Mount the knife in the knifestage of the ultramicrotome and tighten the set screw. Connect the control unit to the power supply. Connect the control unit OUTPUT and the knife with the blue cable. Switch on the control unit (switch ON the back side). Set the resonance frequency (Toggle switch on AUTO). After a few seconds the display will show «Peak locked». Adjust the amplitude to approx. 2 V. Approach the sample with the knife (settings as shown in our diamond knife handling manual. Start sectioning as usual. Measuring the section length Measure the section length with the graticule and compare it with the sample height. If sections are too short, increase the the amplitude (turn the button clockwise). If sections are too long, decrease the amplitude (turn the button counterclock wise). Too high an amplitude may lead to drifting of the sections. Drifting of the sections When working in resonance, the sections may drift slightly to the right or to the left. If this is the case, the following procedure helps: Switching from AUTO to MAN. Now increase or decrease the the frequency a few hundred Hertz, until the sections float straight on the water surface. If sections drift to the right: decrease the frequency. If sections drift to the left: increase the frequency. Front: Back: References: H. Sitte: Advanced Instrumentation and Methodology related to Cryoultramicrotomy: a Review. Scanning Microscopy Supplement 10, pp. 87-466, 1996. M. Michel, H. Gnägi and M. Müller: Diamonds are a cryosectioner's best friend. Journal of Microscopy, Vol. 166, Pt 1, pp. 43-56, 1992. O.L. Reymond: The diamond knife "semi": a substitute for glass or conventional diamond knives in the ultramicrotomy of thin and semi-thin sections. Bas. Applied Histochemistry, No. 30, pp. 487-494, 1986. Various publications on materials ultramicrotomy. Microscopy Research and Technique, Vol. 31. Number 4, pp. 265-310, 1995. L. Edelmann: Freeze-substitution and the preservation of diffusable ions. Journal of Microscopy, Vol. 161, pp. 217-228, 1991. J.C. Jésior: How to avoid compression. Journal of Ultrastructure and Molecular Structure Research, pp. 210-217, 1986. J.C. Jésior: Use of low-angle diamond knives leads to improved ultrastructural preservation of ultrathin sections. Scanning Microscopy Supplement 3, pp. 147-153, 1989. K. Richter: Cutting artefacts on ultrathin cryosections of biological bulk specimens. Micron, Vol. 25, No. 4, pp. 297-308, 1994. K. Richter, H.Gnaegi and J. Dubochet: A model for cryosectioning based on the morphology of vitrified ultrathin sections. Journal of Microscopy, Vol. 163, Pt 1, pp. 19-28, 1991. C.E. Hsieh, M. Marko, J. Frank and C.A. Mannella: Electron tomographic analysis of frozen-hydrated tissue sections. Journal of Structural Biology 138, pp. 63-73, 2002. J.R. McIntosh: Electron Microscopy of Cells: A new beginning of a new century. The journal of Cell Biology, Vol. 153, pp. 25-32, 2001. A. Al-Amoudi, J.Dubochet, H. Gnaegi, W. Lüthi, D.Studer: An oscillating cryo-knife reduces cuttinginduced deformation of vitreous ultrathin sections. Journal of Microscopy, Vol. 212, Pt 1, pp. 26-33, 2003. D. Studer and H. Gnägi: Minimal compression of ultrathin sections with use of an oscillating diamond knife. Journal of Microscopy, Vol. 197, Pt 1, pp. 94-100, 2000. J.S. Vastenhout and H.Gnaegi: Ultramicrotomy of polymers using an oscillating knife; improving polymer morphology. Microscopy and Microanalysis. 8 (Suppl. 2) 2002.
EMS Vacuum Pick-Up System
EMS71895 The complete system consists of a pencil-size probe, an assortment of stainless steel needle tips to match the work, set of seven vacuum cups for heavier parts, a vacuum-in-line filter and a compact U/L approved vacuum generator. The system is powered by a 230V, 50Hz cycle low wattage vibrating pump. Features: The vacuum pick-up system positively and precisely lifts parts varying in size from microscopic to weighing several ounces. Parts are handled without risk of damage or contamination. Defects caused by pinching, scratching or marking are eliminated. Critical surfaces are fully protected. Productivity is increased as parts are handled faster and with greater accuracy. Accessories: 1.2m of lightweight plastic hose in-line filter five assorted stainless steel needle tips three rubberised vacuum cup tips Setup and Tip Selection: Attach the short piece of tubing to the vacuum generator unit. Attach the in-line-filter to the short piece of tubing previously attached. Attach the long tubing to the in-line filter. Attach the pencil size probe to the tubing. Select and attach needle tip to probe. Plug unit into any 230V electrical outlet and turn on by twisting the thumb wheel switch located in the power cord. You are now ready to use your new vacuum pick-up system. Select a tip according to pick-up requirements. The size of the needle selected depends on the size of the article for pick-up. The small vacuum cups may be put at the end of the needle for wafer handling. Direct the vacuum to the tip by placing your index finger over the hole located on the probe. Adjust the vacuum by turning the knob located on the top of the vacuum generator Correcting Vacuum Chatter: These units are adjusted at the factory to optimise pumping. However, line voltage variations may cause the pump to chatter. To eliminate this chatter: Turn the knob located on the top of the generator in a CLOCKWISE direction until the chattering Release the set screw holding the knob. Turn the knob COUNTERCLOCKWISE to the maximum position. Tighten the set screw. After-market Accessories: In-line filter Vacuum cup, 0.400" dia. Vacuum cup, 0.250" dia. Vacuum cup, 0.140" dia. Tip 12 Gauge, 0.093" dia. Tip 16 Gauge, 0.0415" dia. Tip 18 Gauge, 0.0315" dia. Tip 20 Gauge, 0.022" dia. Vacuum pick-up pen only Vacuum pick-up system tubing, 1.2m 230V Pump for vacuum pick-up system
Max Wax Heat Pens for Ultramicrotomy
This instrument is useful for reducing compression artifacts in semi-thin and ultra-thin plastic resin sections. It obviates problems associated with the use of solvent vapour expansion. Advantages of heat-pen method versus solvent use: Better control of heat above the floating sections. Compression artifact is more reduced by using heat. Accidental touching of the surface or sections is a lesser calamity. Toxicity of the solvent vapour is avoided. Operation: The power supply is switched on and the hot filament is moved gently just above the sections (about 1 or 2mm). Sections initial expansion is easily observed through the ultra microtome's stereo microscope. Interference colour of the section will generally change by one shade, indicating reduced thickness and compression. Colours change from gold, to silver, to grey. Keep the tip of the filament at least 1mm away from the boat's sealing wax. Compression reduction: Studies have shown that unstretched Araldite sections are compressed (shorter than the block face) by 24-25%. Stretching with solvent vapour leaves 5-6% and heat stretching leaves 2-5% compression. Heat stretching is superior in all tested resins. Physical data: Powered by two AA batteries The heat pen filament is interchangeable. Avoid bending the filament tip. Broken filaments may be replaced or can be repaired with a piece of nichrome wire or thin platinum wire. Crimp wire or use silver dag.
PELCO Vacuum Pick-up System
Handle and transport grids and wafers without the use of tweezers NOTE: Not for wet or corrosive materials. Use this system for picking up delicate lightweight material with finger-controlled vacuum. Attach various hollow needle tips (5 with system) or rubber cups (3 with system) onto the pick-up pen. Use easy finger control for picking up or releasing. The PELCO Vacuum Pick-Up System is powered by 220V, 50Hz cycle low wattage vibrator-type pump. The unit comes fully assembled except for the accessories. The accessories consist of 3cm of lightweight plastic hose, an in-line filter, five assorted stainless-steel tips, 3 cups and a Vacuum Pick-up Pen. The in-line filter is placed adjacent to the pump with the 30cm plastic hose following. The individual needles are used according to the customer’s pick-up requirements. The size of the needle selected depends on the size of the article for pick-up. If soft, easily-marred wafers are to be picked up, the small vacuum cups may be put at the end of the needle. After turning the unit on, the Vacuum Pick-Up Pen is held in a similar way to a pen, with the index finger near the opening. To “pick up” an object, the index finger is placed over the hole so that vacuum is drawn through the needle or cup. The object is then released by lifting the index finger off the opening. The procedure is repeated until the work is completed. Accessories and replacement items are available: In-line Filter Vacuum Cup, 0.400” dia. Vacuum Cup, 0.250” dia. Vacuum Cup, 0.140” dia. Tip 12 Gauge, 0.093” dia. Tip 16 Gauge, 0.0415” dia. Tip 18 Gauge, 0.0315” dia. Tip 20 Gauge, 0.022” dia. Vacuum Pick-Up Pen only, each Vacuum Pick-Up System Tubing 4’ 220V Pump for Vacuum Pick-up System
Precision Brain Punches
Precision brain punches for Microdissection of Frozen Brain Sections The kit is available in 2 different sets: Complete with either 3 punches or 5 come complete with spring loaded nylon expellers, and a convenient handle, facilitates the "Palkovits Punch" technique of dissecting out specific brain nuclei for neurochemistry. The nuclei are punched from frozen brain sections on glass slides, and expelled into the reagents. The spring-loaded expellers avoid risk of contamination that might be caused by expelling with breath. Each punch has an electro polished sharp end for smooth cuts and minimal tissue adhesion. Punch sizes are 0.25, 0.50, 0.75, 1.0, 1.25, 1.50, 1.75 and 2.00 (± 5%, slight variation due to electro polish etching to sharpen). The smaller tubes are reinforced by an outer layer of concentric tubing except at the tip. Replacement punches available individually. Applications: The Brain Punch Kit is a set of electropolished and sharpened punches for the Palkovit's punch technique. Note that the smaller punches are reinforced, as these can tend to bend under the force of the punching action. The set includes a handle and 5 sizes of punches. Sizes are shown in the table below. Each punch consists of the stainless steel punch column, the holder body, and a button which operates a spring loaded expeller to force the micro dot of tissue from the punch. Select the punch to be used and install it in the handle so that the black body holder on the punch is flush with the lower surface of the handle. Tighten the locking screw. If the punch body holder extends below the handles bottom surface, the action of the expeller may be blocked. Check that the expeller end can be seen when the button is pressed, and then proceed. Method: To prevent deterioration of the proteins, the tissue must be kept frozen as much as possible. The brain or other tissue to be punched is dissected from the anesthetised animal and dropped into liquid nitrogen. The frozen specimen is mounted on a sectioning pedestal, placed in a cryostat, and allowed to equilibrate to the cryostat temperature. At this time, glass slides for collection of the sections are also placed in the cryostat to equilibrate to the temperature. The specimen must be adjusted to the correct plane of section, taking preliminary sections to check the angle, and then the critical sections from the desired region are collected. Thick (~200µm) are taken and placed on the prechilled glass slides. The frozen slices will lie on the frozen glass without adhering, so care must be taken not to spill them. When the slide is full, press a finger against the bottom of the slide to cause the tissue to partially thaw into contact with the slide, and refreeze promptly in the cryostat. Remove the slides from the cryostat and place on a cold plate or petri dish chilled with dry ice. Select the punch needed, position the tip over the area to be removed, and press down. The dot of tissue, whose volume can be calculated, will pull away from glass slide and stay in the punch. Press the spring-loaded button on top of each punch to expel the tissue into the collection media.
Quick Boat (6.4mm Glass Knife)
UL072 Quick Boat can be used as a glass knife boat or similar knife boat. The Quick Boat is fast and offers easy handling, by just turning a screw. As well, it comes with soft silicone rubber for sealing and it is reusable. The Quick Boat is fixed into the case with a lock plate. To remove: hold the Quick Boat with one hand and loosen the locking screw with the other. Setting the boat to the knife: place the boat on the knife gently. For sealing, there is a soft silicone rubber. To keep water-tight, 6 glass balls are attached to the silicone rubber. To Use: Set the knife to the ultra microtome and attach Quick Boat to the knife by using a stereo microscope. Adjust the height of the boat and the knife edge so they are almost the same level. Adjust the angle of the boat so that they are on the same level. During adjustment touch both glass knife and boat with your fingers so that it is easy to confirm the angle of the boat. Lock the boat once the height and angle adjustments are complete by tightening the locking screw to fix the boat in place. Note: When placing the boat on the knife, make sure the knife is fixed in position with the ultra microtome before setting the boat. If not fixed it may cause damage to the silicone rubber. Do not use the left side of the screw hole - this hole is required for production purposes only.