The authors would like to thank Prof. Nicholas Smirnoff of the University of Exeter for his advice and the University of Exeter Bioimaging Facility. Funding was provided by the UK Biotechnology and Biological Sciences Research Council (grant reference BB/E002682/1).

The protocol given below describes a simple method for using PFD as an infiltrative mounting medium in Arabidopsis thaliana leaves, but we anticipate that this method may be used in a variety of applications where imaging air-rich tissues is desired.
1. Mounting leaf samples in PFD
<ol>
 <li>Prepare a microscope slide with a gas-permeable gasket of polydimethylsiloxane (PDMS, Carolina Observation Gel). PDMS is a viscoelastic polymer and can be molded to provide a chamber tailored to experimental requirements.</li>
 <li>Equilibrate PFD with air. This may be achieved by bubbling with air or by shaking a small volume of PFD in an air-filled bottle.</li>
 <li>Decant PFD into an open Petri dish and float a whole seedling or excised leaf on PFD for 5 minutes. The tissue should become translucent, reminiscent of vitrified tissue (Figure 2 (a)). Leaves may appear darker or lighter than before exposure to PFD, depending on lighting conditions and the age of tissue used.</li>
 <li>Fill the PDMS chamber with air-equilibrated PFD and carefully transfer the tissue samples from the incubation Petri dish to the PDMS chamber. Seal the slide with a coverslip and image according to experimental requirements.</li>
 <li>Note: PFD also performs well in an open chamber constructed on a coverslip or in a perfusion chamber and is compatible with silicon grease. PFD is not compatible with Teflon components as it dissolves them.</li>
</ol>
2. Representative Results:
Microscopic inspection of PFD-incubated leaf samples shows that the majority of airspaces are flooded. Figure 2 (b) shows airspaces flooded with recombinant GFP suspended in PFD. It is apparent that the leaf is flooded upon incubation with PFD, but that occasional pockets of air may remain. Water does not flood the leaf under these conditions. LSCM of samples incubated and mounted in air, water or PFD shows that PFD gives an advantage over water and air in the depth of imaging possible (Figure 3). The example given in Figure 3 shows air, water and PFD mounted Arabidopsis leaves expressing cytosolically localized Venus, a variant of YFP11 that is expressed constitutively under the 35S promoter. We can see an approximate 2-fold increase in depth of imaging when comparing PFD and water. It should be noted, however, that the precise improvement seen when using PFD varies with numerical aperture of the lens and the type of tissue used. We have seen cytoplasmic streaming and root hair elongation in PFD treated seedlings, each indicative of healthy plants. In addition we have shown2 that Fv/Fm, a measure of the photosynthetic functioning of plants12 remains within tolerable limits over timescales used in imaging.
<img alt="Figure 1." src="/files/ftp_upload/3394/3394fig1.jpg" /> 
Figure 1. Plant leaf complexity and optical implications 
Diagrammatical representation showing the anatomical features of the A. thaliana leaf in relation to the optical set-up. Abbreviations used are obj. = objective lens, imm. = immersion fluid, cov. = coverslip, mnt. = mountant, cut. = cuticle, ad. ep. = adaxial epidermis, st. = stomatal pore, sp. = spongy mesophyll, a.s. = air space, pal. = palisade mesophyll, v.b. = vascular bundle, ad. ep. = adaxial epidermis. Cell walls are indicated by black lines.
<img alt="Figure 2." src="/files/ftp_upload/3394/3394fig2.jpg" /> 
Figure 2. PFD readily penetrates Arabidopsis leaves 
(a) Leaves incubated in air, water or PFD for 5 minutes and imaged using a Leica DCF3000FX digital camera with a Leica MZ16F microscope (Leica Microsystems (UK) Ltd., Milton-Keynes, UK). The JoVE logo was printed on acetate film and illuminated from below with a light box. Exposure time was 89 ms and all images were collected and processed identically. Scale bars represent 2 mm. 
 
(b) PFD carrying purified recombinant green fluorescent protein (GFP) delimits airspaces in vivo. GFP is false coloured green, and red is used to show chlorophyll auto-fluorescence, which delimits the mesophyll cells. (Figure 2(b) reproduced with permission and full technical details available in Littlejohn et al. 20102). Scale bars represent 25 m.
<img alt="Figure 3." src="/files/ftp_upload/3394/3394fig3.jpg"/> 
Figure 3. PFD improves confocal imaging in leaves 
LSCM images showing cytoplasmically localised Venus fluorescence (green) and chlorophyll autofluorescence (red) in intact A. thaliana leaves imaged in air, water or PFD. Excitation wavelength was 514 nm and fluorescence emission was recorded at 518 nm 604 nm for Venus and at 657 nm 679 nm for chloroplasts. Each panel is a single confocal section taken from a Z-stack of 11 confocal images acquired at 5 &mu;m intervals. These were extracted from a full Z-stack of 59 images acquired at 1 &mu;m intervals, which have been used to produce supplementary movies. Depth measurements are given relative to the epidermal surface. Representative images, which were processed identically, are shown. Experimental details such as microscope settings are identical to those found in Littlejohn et al., 20102. Scalebars represent 20 &mu;m.

<ol>
	<li>Inoue, S., Pawley, J. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Foundations+of+Confocal+Scanned+Imaging+in+Light+Microscopy.">Foundations of Confocal Scanned Imaging in Light Microscopy.</a> Handbook of Biological Confocal Microscopy, 3rd. , 1-16 (2006).</li><li>Littlejohn, G. R., Gouveia, J. D., Edner, C. S. m. i. r. n. o. f. f., N, ., Love, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Perfluorodecalin+substantially+improves+confocal+depth+resolution+in+air-filled+tissues.">Perfluorodecalin substantially improves confocal depth resolution in air-filled tissues.</a> New. Phytologist. 186, 1018-1025 (2010).</li><li>Sargent, J. W., Seffl, R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Properties+of+perfluorinated+liquids.+Fed.">Properties of perfluorinated liquids. Fed.</a> Fed. Proc. 29, 1699-1703 (1970).</li><li>Sch&#246;nherr, J., Bukovac, M. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Penetration+of+stomata+by+liquids.">Penetration of stomata by liquids.</a> Plant Physiol. 49, 813-819 (1972).</li><li>Davies, M. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Liquid+ventilation.">Liquid ventilation.</a> Paediatr. Child. Health. 35, 434-437 (1999).</li><li>Shaffer, T. H., Wolfson, M. R., Greenspan, J. S., Hoffman, R. E., Davis, S. L., Clark, L. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Liquid+ventilation+in+premature+lambs:+uptake,+biodistribution+and+elimination+of+perfluorodecalin+liquid.">Liquid ventilation in premature lambs: uptake, biodistribution and elimination of perfluorodecalin liquid.</a> Reprod. Fertil. Dev. 8, 409-416 (1996).</li><li>Crafoord, S., Larsson, J., Hansson, L. J., Carlsson, J. O., Stenkula, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+use+of+perfluorocarbon+liquids+in+vitreoretinal+surgery.">The use of perfluorocarbon liquids in vitreoretinal surgery.</a> Acta. Ophthalmol. Scand. 73, 442-445 (1995).</li><li>Lowe, K. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Engineering+blood:+synthetic+substitutes+from+fluorinated+compounds.">Engineering blood: synthetic substitutes from fluorinated compounds.</a> Tissue Eng. 9, 389-399 (2003).</li><li>Wardrop, J., Edwards, C. M., Lowe, K. C., Davey, M. R., Power, J. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cellular+responses+of+plant+protoplasts+to+culture+with+oxygenated+perfluorocarbon.">Cellular responses of plant protoplasts to culture with oxygenated perfluorocarbon.</a> Adv. Exp. Med. Biol. 428, 501-505 (1997).</li><li>Sukumaran, N. P., Quamme, H., Weiser, C. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+fluorocarbons+to+study+freezing+in+plant+tissues.">Use of fluorocarbons to study freezing in plant tissues.</a> Plant Physiol. 50, 632-634 (1972).</li><li>Nagai, T., Ibata, K., Park, E. S., Kubota, M., Mikoshiba, K., Miyawaki, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+variant+of+yellow+fluorescent+protein+with+fast+and+efficient+maturation+for+cell-biological+applications.">A variant of yellow fluorescent protein with fast and efficient maturation for cell-biological applications.</a> Nat. Biotechnol. 20, 87-90 (2002).</li><li>Baker, N. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chlorophyll+fluorescence:+a+probe+of+photosynthesis+in+vivo.">Chlorophyll fluorescence: a probe of photosynthesis in vivo.</a> Annu. Rev. Plant. Biol. 59, 89-113 (2008).</li></ol>

No conflicts of interest declared.

This is a simple and easy to use technique to improve microscopy of air-filled or optically complex tissues. We have shown that the technique has some strong advantages and we hope that it will be used to elucidate biological questions pertaining to air-rich tissues. For example it would be a natural choice for studies of pathogen attack in plant mesophyll or in lungs. We also are aware of the limitations of the technique. We are working on better refractive index matching, use with other modes of microscopy, and perfluorocarbon mountant replenishment during long timescale experiments. We also recognise, though, that one of the main advantages of PFCs, namely being biologically inert has a flipside. PFCs do not readily dissolve biological molecules which also implies that they cannot be easily used to deliver compounds of interest such as hormones, drugs, and other small molecules or ions.

<table border="1">
 <tbody>
 <tr>
 <td>Name of the reagent</td>
 <td>Company</td>
 <td>Catalogue number</td>
 <td>Comments</td>
 </tr>
 <tr>
 <td>Perfluorodecalin</td>
 <td>F2 Chemicals</td>
 <td>N/A</td>
 <td>Telephone to order.</td>
 </tr>
 <tr>
 <td>Carolina Observation Gel</td>
 <td>Blades Biological</td>
 <td>13-2700</td>
 <td></td>
 </tr>
 </tbody>
 </table>

a simple method for imaging arabidopsis leaves using perfluorodecalin as an infiltrative imaging medium

The problem of acquiring high-resolution images deep into biological samples is widely acknowledged1. In air-filled tissue such as the spongy mesophyll of plant leaves or vertebrate lungs further difficulties arise from multiple transitions in refractive index between cellular components, between cells and airspaces and between the biological tissue and the rest of the optical system. Moreover, refractive index mismatches lead to attenuation of fluorophore excitation and signal emission in fluorescence microscopy. We describe here the application of the perfluorocarbon, perfluorodecalin (PFD), as an infiltrative imaging medium which optically improves laser scanning confocal microscopy (LSCM) sample imaging at depth, without resorting to damaging increases in laser power and has minimal physiological impact2. We describe the protocol for use of PFD with Arabidopsis thaliana leaf tissue, which is optically complex as a result of its structure (Figure 1). PFD has a number of attributes that make it suitable for this use3. The refractive index of PFD (1.313) is comparable with that of water (1.333) and is closer to that of cytosol (approx. 1.4) than air (1.000). In addition, PFD is readily available, non-fluorescent and is non-toxic. The low surface tension of PFD (19 dynes cm-1) is lower than that of water (72 dynes cm-1) and also below the limit (25 - 30 dyne cm-1) for stomatal penetration4, which allows it to flood the spongy mesophyll airspaces without the application of a potentially destructive vacuum or surfactant. Finally and crucially, PFD has a great capacity for dissolving CO2 and O2, which allows gas exchange to be maintained in the flooded tissue, thus minimizing the physiological impact on the sample. These properties have been used in various applications which include partial liquid breathing and lung inflation5,6, surgery7, artificial blood8, oxygenation of growth media9, and studies of ice crystal formation in plants10. Currently, it is common to mount tissue in water or aqueous buffer for live confocal imaging. We consider that the use of PFD as a mounting medium represents an improvement on existing practice and allows the simple preparation of live whole leaf samples for imaging.

Watch this Scientific Journal Video about A Simple Method for Imaging Arabidopsis Leaves Using Perfluorodecalin as an Infiltrative Imaging Medium at JoVE.com

A Simple Method for Imaging Arabidopsis Leaves Using Perfluorodecalin as an Infiltrative Imaging Medium

We describe the use of perfluorodecalin as an infiltrative mounting medium. This is a simple method for improving depth of imaging in Arabidopsis thaliana leaf tissue with minimal physiological impact.

A Simple Method for Imaging Arabidopsis Leaves Using Perfluorodecalin as an Infiltrative Imaging Medium

The problem of acquiring high-resolution images deep into biological samples is widely acknowledged1. In air-filled tissue such as the spongy mesophyll of ...

a-simple-method-for-imaging-arabidopsis-leaves-using-perfluorodecalin

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21.5K Views.  The University of Exeter. We describe the use of perfluorodecalin as an infiltrative mounting medium. This is a simple method for improving depth of imaging in Arabidopsis thaliana leaf tissue with minimal physiological impact.

Video: A Simple Method for Imaging Arabidopsis Leaves Using Perfluorodecalin as an Infiltrative Imaging Medium

Pyrosequencing: A Simple Method for Accurate Genotyping

Pharmacogenetic research benefits first-hand from the abundance of information provided by the completion of the Human Genome Project. With such a tremendous amount of data available comes an explosion of genotyping methods. Pyrosequencing(R) is one of the most thorough yet simple methods to date used to analyze polymorphisms. It also has the ability to identify tri-allelic, indels, short-repeat polymorphisms, along with determining allele percentages for methylation or pooled sample assessment. In addition, there is a standardized control sequence that provides internal quality control. This method has led to rapid and efficient single-nucleotide polymorphism evaluation including many clinically relevant polymorphisms. The technique and methodology of Pyrosequencing is explained.


Pyrosequencing(R) is one of the most thorough yet simple methods to date used to analyze polymorphisms. This method has led to rapid and efficient single-nucleotide polymorphism evaluation including many clinically relevant polymorphisms. The technique and methodology of Pyrosequencing is explained.

Pharmacogenetic research benefits first-hand from the abundance of information provided by the completion of the Human Genome Project. With such a ...

An ex-ovo Chicken Embryo Culture System Suitable for Imaging and Microsurgery Applications

Understanding the relationships between genetic and microenvironmental factors that drive normal and malformed embryonic development is fundamental for discovering new therapeutic strategies. Advancements in imaging technology have enabled quantitative investigation of the organization and maturing of the body plan, but later stage embryonic morphogenesis is less clear. Chicken embryos are an attractive vertebrate animal model system for this application because of its ease of culture and surgical manipulation. Early embryos can be cultured for a short time on filter paper rings, which enables complete optical access for cell patterning and fate studies1,2. Studying advanced developmental processes such as cardiac morphogenesis are traditionally performed through a window of the eggshell3-5, but this technique limits optical access due to window size. We previously developed a simple method to culture whole embryos ex-ovo on hexagonal weigh boats for up to 10 days, which enabled high resolution imaging via ultrasonography6,7. These cultures were difficult to transport, limiting the types of imaging tools available for live experiments. We here present an improved shell-less culture system with a cost-effective, portable environmental chamber. Eggs were cracked onto a hammock created by a polyurethane membrane (cling wrap) affixed circumferentially to a plastic cup partially filled with sterile water. The dimensions of the circumference and depth of the hammock were both critical to maintain surface tension, while the mechanics of the hammock and water beneath helped dampen vibrations induced by transportation. A small footprint circulating water bath was also developed to enable continuous temperature control during experimentation. We demonstrate the ability to culture embryos in this way for at least 14 days without morphogenic defect or delay and employ this system in several microsurgical and imaging applications.

An ex-ovo Chicken Embryo Culture System Suitable for Imaging and Microsurgery Applications

In this article, we present a simple methodology to enable long-term ex-ovo avian embryo culture. This technique is ideal for longitudinal experimentation requiring complete optical accessibility and/or sterile transportation in avian embryos.

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Quantifying Mixing using Magnetic Resonance Imaging

Mixing is a unit operation that combines two or more components into a homogeneous mixture. This work involves mixing two viscous liquid streams using an in-line static mixer. The mixer is a split-and-recombine design that employs shear and extensional flow to increase the interfacial contact between the components. A prototype split-and-recombine (SAR) mixer was constructed by aligning a series of thin laser-cut Poly (methyl methacrylate) (PMMA) plates held in place in a PVC pipe. Mixing in this device is illustrated in the photograph in Fig. 1. Red dye was added to a portion of the test fluid and used as the minor component being mixed into the major (undyed) component. At the inlet of the mixer, the injected layer of tracer fluid is split into two layers as it flows through the mixing section. On each subsequent mixing section, the number of horizontal layers is duplicated. Ultimately, the single stream of dye is uniformly dispersed throughout the cross section of the device.
 Using a non-Newtonian test fluid of 0.2% Carbopol and a doped tracer fluid of similar composition, mixing in the unit is visualized using magnetic resonance imaging (MRI). MRI is a very powerful experimental probe of molecular chemical and physical environment as well as sample structure on the length scales from microns to centimeters. This sensitivity has resulted in broad application of these techniques to characterize physical, chemical and/or biological properties of materials ranging from humans to foods to porous media 1, 2. The equipment and conditions used here are suitable for imaging liquids containing substantial amounts of NMR mobile 1H such as ordinary water and organic liquids including oils. Traditionally MRI has utilized super conducting magnets which are not suitable for industrial environments and not portable within a laboratory (Fig. 2). Recent advances in magnet technology have permitted the construction of large volume industrially compatible magnets suitable for imaging process flows. Here, MRI provides spatially resolved component concentrations at different axial locations during the mixing process. This work documents real-time mixing of highly viscous fluids via distributive mixing with an application to personal care products.

Magnetic resonance imaging (MRI) provides a powerful tool to evaluate the effectiveness of process equipment during operation. We discuss the use of MRI to visualize mixing in a static mixer. The application is relevant to personal care products, but can be applied to a broad range of food, chemical, biomass and biological fluids.

Mixing is a unit operation that combines two or more components into a homogeneous mixture.  This work involves mixing two viscous liquid streams using an ...

Cell Specific Analysis of Arabidopsis Leaves Using Fluorescence Activated Cell Sorting

After initiation of the leaf primordium, biomass accumulation is controlled mainly by cell proliferation and expansion in the leaves1. However, the Arabidopsis leaf is a complex organ made up of many different cell types and several structures. At the same time, the growing leaf contains cells at different stages of development, with the cells furthest from the petiole being the first to stop expanding and undergo senescence1. Different cells within the leaf are therefore dividing, elongating or differentiating; active, stressed or dead; and/or responding to stimuli in sub-sets of their cellular type at any one time. This makes genomic study of the leaf challenging: for example when analyzing expression data from whole leaves, signals from genetic networks operating in distinct cellular response zones or cell types will be confounded, resulting in an inaccurate profile being generated.
To address this, several methods have been described which enable studies of cell specific gene expression. These include laser-capture microdissection (LCM)2 or GFP expressing plants used for protoplast generation and subsequent fluorescence activated cell sorting (FACS)3,4, the recently described INTACT system for nuclear precipitation5 and immunoprecipitation of polysomes6.
FACS has been successfully used for a number of studies, including showing that the cell identity and distance from the root tip had a significant effect on the expression profiles of a large number of genes3,7. FACS of GFP lines have also been used to demonstrate cell-specific transcriptional regulation during root nitrogen responses and lateral root development8, salt stress9 auxin distribution in the root10 and to create a gene expression map of the Arabidopsis shoot apical meristem11. Although FACS has previously been used to sort Arabidopsis leaf derived protoplasts based on autofluorescence12,13, so far the use of FACS on Arabidopsis lines expressing GFP in the leaves has been very limited4. In the following protocol we describe a method for obtaining Arabidopsis leaf protoplasts that are compatible with FACS while minimizing the impact of the protoplast generation regime. We demonstrate the method using the KC464 Arabidopsis line, which express GFP in the adaxial epidermis14, the KC274 line, which express GFP in the vascular tissue14 and the TP382 Arabidopsis line, which express a double GFP construct linked to a nuclear localization signal in the guard cells (data not shown; Figure 2). We are currently using this method to study both cell-type specific expression during development and stress, as well as heterogeneous cell populations at various stages of senescence.

Cell Specific Analysis of Arabidopsis Leaves Using Fluorescence Activated Cell Sorting

A method for producing Arabidopsis leaf protoplasts that are compatible with fluorescence activated cell sorting (FACS), allowing for studies of specific cell populations. This method is compatible with any Arabidopsis line that expresses GFP in a subset of cells.

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Setting Up a Simple Light Sheet Microscope for In Toto Imaging of C. elegans Development

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The Infiltration-centrifugation Technique for Extraction of Apoplastic Fluid from Plant Leaves Using Phaseolus vulgaris as an Example

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The Infiltration-centrifugation Technique for Extraction of Apoplastic Fluid from Plant Leaves Using Phaseolus vulgaris as an Example

This protocol details the optimized extraction of apoplast washing fluid from plant leaves, using French bean plants (Phaseolus vulgaris) as a model example.

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FRET Imaging in Three-dimensional Hydrogels

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Discrimination and Characterization of Heterocellular Populations Using Quantitative Imaging Techniques

Cellular processes are complex and result from the interplay between multiple cell types and their environment. Existing cell biology techniques often do not allow for accurate interpretation of this interplay. Using a quantitative imaging-based approach, we present a high-content protocol for characterizing the dynamic phenotypic responses (i.e. morphology changes, proliferation, apoptosis) of heterogeneous cell populations to changes in environmental stimuli. We highlight our ability to distinguish between cell types based upon either fluorescence intensity or inherent morphology features depending on the application. This platform allows for a more comprehensive characterization of subpopulation response to perturbation while utilizing shorter time, smaller amounts of reagents, and lower likelihood of error than traditional cell biology assays. However, in some cases, cell populations may be difficult to identify and quantitate based on complex cellular features and will require additional troubleshooting; we highlight some of these circumstances in the protocol. We demonstrate this application using response to drug in a cancer model; however, it can easily be applied more broadly to other physiological processes. This protocol allows one to identify subpopulations within a co-culture system and characterize the particular response of each to external stimuli.

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Standardized Method for High-throughput Sterilization of Arabidopsis Seeds

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Luciferase Complementation Imaging Assay in Nicotiana benthamiana Leaves for Transiently Determining Protein-protein Interaction Dynamics

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A Simple Method for Imaging Arabidopsis Leaves Using Perfluorodecalin as an Infiltrative Imaging Medium

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Pyrosequencing: A Simple Method for Accurate Genotyping

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Cell Specific Analysis of Arabidopsis Leaves Using Fluorescence Activated Cell Sorting

Setting Up a Simple Light Sheet Microscope for In Toto Imaging of C. elegans Development

The Infiltration-centrifugation Technique for Extraction of Apoplastic Fluid from Plant Leaves Using Phaseolus vulgaris as an Example

FRET Imaging in Three-dimensional Hydrogels

Discrimination and Characterization of Heterocellular Populations Using Quantitative Imaging Techniques

Standardized Method for High-throughput Sterilization of Arabidopsis Seeds

Luciferase Complementation Imaging Assay in Nicotiana benthamiana Leaves for Transiently Determining Protein-protein Interaction Dynamics