Boster Bio Life Science Blog

In conducting immunohistochemistry (IHC) and immunofluorescence (IF) experiments, one crucial step is the fixation of cells to preserve them. This prevents cell autolysis and degradation caused by proteolytic enzymes and increases the mechanical strength of the cell structure. Fixation ensures the cell's morphology and structure remain intact, maintaining a "lifelike" appearance.

Drosophila melanogaster, commonly known as the fruit fly, has long been a cornerstone of genetic research. Its simplicity, rapid life cycle, and genetic tractability make it an invaluable model organism for scientists worldwide.

If you’re considering using Drosophila for your research studies, this guide is for you. In this blog, we delve into key breakthroughs that used Drosophila in research, explore the advantages and limitations of using Drosophila for research, and highlight the research areas where the fruit fly has made significant contributions. Additionally, we provide some resources and funding supporting Drosophila research, along with reflective questions to help you decide if this model organism is right for your studies.

Feel free to jump to a specific section about Drosophila:

• About Drosophila
• Brief History and Key Breakthroughs using Drosophila
• Advantages of Drosophila as a Model Organism
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Immunotherapy, a treatment that uses someone’s own immune system to target and attack cancer cells is the next and best frontier of cancer treatment. CAR-T stands for Chimeric Antigen Receptor T-cell. It refers to a type of immunotherapy where T-cells are engineered to produce special receptors on their surface that help them target and kill cancer cells. Like all immunotherapy, CAR-T cell therapy harnesses the p

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This article discusses the definition of cell lysis and basic methods, with a focus on the components, selection, and usage steps of chemical lysis buffers.

Cancer metastasis is a leading cause of poor prognosis in cancer patients and represents a central challenge in oncology research. The process of metastasis is highly complex and involves multiple steps: local invasion, entry into the circulatory system, dissemination through blood or lymphatic vessels, seeding in distant tissues, and subsequent growth in a new environment.

Paraformaldehyde is primarily used in biological and biomedical research for fixing cells and tissues. When dissolved in a buffer like PBS (phosphate-buffered saline) to make a 4% solution, its main function is to crosslink proteins within cells and tissues. This fixation process preserves cellular morphology and prevents degradation, enabling various microscopic techniques such as immunostaining and microscopy for detailed analysis of cellular structures and protein localization.

Antibody conjugates are essential tools in biological research, offering both specificity and sensitivity for detecting and quantifying proteins, cells, and other molecules. Below, we explore the most common types of antibody conjugates, their examples, applications, and popularity in research.

What is antibody conjugation?

Antibody conjugation is the process of chemically linking an antibody to another molecule, such as a fluorescent dye, enzyme, biotin, or nanoparticle. This process enhances the antibody’s ability to detect specific targets by enabling visualization or measurement in various assays. Conjugated antibodies are widely used in research for applications like flow cytometry, ELISA, and immunofluorescence, where they facilitate the detection and analysis of specific proteins or cells in complex samples. In some experimental setups, especially those involving gene delivery or expression studies, related tools such as AAV Packaging Service may also be employed to introduce genetic material efficiently into target cells. These conjugates are often produced as part of comprehensive antibody production services, where antibodies are not only generated but also tailored with the appropriate labels to suit specific experimental needs.

Common types of antibody conjugates

Fluorophore Conjugates

Among the most commonly used are fluorophore conjugates, which include dyes like fluorescein isothiocyanate (FITC), cyanine dyes, DyLight® dyes, allophycocyanin (APC), phycoerythrin (PE), R-phycoerythrin (R-PE), and iFluor® dyes.

• Fluorescein isothiocyanate (FITC): FITC is a green fluorescent dye commonly used in flow cytometry and immunofluorescence microscopy.
• Cyanine Dyes (e.g., Cy3, Cy5): Cyanine dyes are used for multiplexing due to their distinct spectral properties.
• DyLight® Dyes: The DyLight® dyes are a series of high-performance dyes known for their photostability, brightness, and versatility. Popularly used DyLight® dyes include DyLight® 488, 550, 594, 650, and 800 are popularly used in applications such as flow cytometry, immunofluorescence microscopy, and Western blotting.
• Allophycocyanin (APC): APC is a red fluorescent protein used in flow cytometry for its high quantum yield.
• Phycoerythrin (PE): PE is a general term for phycoerythrin proteins derived from various algae species. It is widely used in flow cytometry and fluorescence microscopy due to its bright fluorescence.
• R-phycoerythrin (R-PE): R-PE, derived specifically from red algae, is a highly bright red-orange fluorescent protein used in flow cytometry and other fluorescent applications. It offers even greater brightness due to its multiple chromophores. This makes R-PE ideal for applications requiring high sensitivity and resolution, such as multicolor flow cytometry.
• iFluor® Dyes: iFluor® dyes, including iFluor® 488, 555, 594, 647, and 750, are designed for superior brightness and photostability, making them excellent choices for advanced fluorescence imaging techniques and multicolor applications.

Fluorophore-conjugated antibodies are widely used in:

• Flow Cytometry: For analyzing cell populations by measuring fluorescence intensity.
• Immunofluorescence: For visualizing protein localization in cells or tissue sections.
• Confocal Microscopy: For high-resolution imaging of fluorescently labeled samples.

Below, we have provided a table comparing key characteristics and uses of some of the most common fluorophore conjugates in research.

Fluorophore	Color	Max Excitation (nm)	Max Emission (nm)	Extinction Coefficient (M⁻¹cm⁻¹)	Advantages	Applications
FITC	Green	495	519	70,000	Bright, photostable, common filter sets	Flow cytometry, immunofluorescence, microscopy
Cy3	Orange	552	570	150,000	Bright, used in multiplexing	Flow cytometry, immunofluorescence, FISH
Cy5	Red	650	670	250,000	Near-infrared, high sensitivity	Flow cytometry, imaging, FRET
DyLight® 488	Green	493	518	70,000	Bright, photostable	Flow cytometry, immunofluorescence, microscopy
DyLight® 550	Orange	562	576	150,000	High brightness, photostable	Western blotting, fluorescence microscopy, flow cytometry
DyLight® 594	Red	593	618	115,000	Bright, minimal spectral overlap	Multicolor fluorescence imaging, flow cytometry
DyLight® 650	Far-red	652	672	250,000	Near-infrared, reduced background	Flow cytometry, fluorescence imaging
DyLight® 800	Near-IR	783	800	270,000	Near-infrared, minimal autofluorescence	In vivo imaging, Western blotting, NIR fluorescence imaging
iFluor® 488	Green	491	516	70,000	Bright, photostable, FITC alternative	Flow cytometry, immunofluorescence, confocal microscopy
iFluor® 555	Orange	555	565	150,000	High brightness, photostable	Fluorescence microscopy, flow cytometry, multicolor applications
iFluor® 594	Red	590	615	115,000	Bright, minimal spectral overlap	Multicolor fluorescence imaging, flow cytometry
iFluor® 647	Far-red	650	665	250,000	High brightness, photostable	Flow cytometry, fluorescence imaging, super-resolution microscopy
iFluor® 750	Near-IR	755	779	270,000	Near-infrared, minimal autofluorescence	In vivo imaging, NIR fluorescence imaging
APC	Red	650	660	700,000	High quantum yield, photostable	Flow cytometry, imaging
PE	Orange	480-565	575-590	1,960,000	High brightness, quantum yield	Flow cytometry, fluorescence microscopy
R-PE	Red-orange	488, 546, 565	575-585	1,960,000	Extremely bright, multiple chromophores	Flow cytometry, high sensitivity applications

Fluorophore conjugates are very popular due to their versatility, high sensitivity, and the variety of available dyes that allow multiplexing. When searching for primary antibodies and secondary antibodies at Boster, you’ll be able to select from a range of conjugation options, such as Cy3, DyLight® dyes, FITC, APC, PE, or iFluor® dyes. You can also request custom antibody conjugation with our antibody conjugation service, which offers more conjugate labels.

Enzyme Conjugates

Enzyme conjugates, such as those linked to horseradish peroxidase (HRP) and alkaline phosphatase (AP), are also commonly used in research. These conjugates are crucial in assays like ELISA, WB, and IHC. In particular, enzyme-conjugated antibodies are widely utilized in sandwich ELISA formats, where the precise coordination between the capture and detection antibodies is essential for achieving optimal signal development and minimizing background interference. Antibody Pair Development Service develops matched antibody pairs for these assays involving careful selection to ensure that the antibodies bind to non-competing epitopes with high affinity and stability across varying assay conditions.

• Horseradish Peroxidase (HRP): HRP is an enzyme that catalyzes the oxidation of substrates, producing a detectable signal. The conjugate is regularly used in ELISA and Western blotting. HRP is particularly favored for its high signal-to-noise ratio, making it a staple in laboratory assays.
• Alkaline Phosphatase (AP): AP is an enzyme that hydrolyzes phosphate groups, and this conjugate can be utilized in ELISA, Western blotting, and immunohistochemistry.

Enzyme-conjugated antibodies are used in:

• ELISA (Enzyme-Linked Immunosorbent Assay): For quantitative measurement of proteins in samples.
• Western Blotting: For protein detection after gel electrophoresis.
• Immunohistochemistry: For detecting antigens in tissue sections using colorimetric reactions.

Enzyme conjugates are highly popular in routine laboratory assays due to their robustness and ease of use. However, when assays demand superior specificity and minimal background noise, especially in enzyme-linked applications like ELISA and Western blotting, sourcing antibodies through specialized Rabbit Monoclonal Antibody Services can provide researchers with tailored solutions that consistently deliver reliable signal detection in complex biological samples. At Boster Bio, you can find primary antibodies and secondary antibodies conjugated to HRP, AP, and more. In addition, you can select specific conjugates for your antibodies with our custom antibody conjugation service.

Biotin Conjugates

Biotin, a vitamin that can be easily bound by streptavidin, has proven to be another essential antibody conjugate in research. It provides significant advantages due to its amplification capabilities. Biotin-labeled antibodies, often paired with streptavidin-HRP or AP, are used by researchers in ELISA, Western blotting, and immunohistochemistry.

In research, biotin-conjugated antibodies are frequently used in:

• ELISA and Western Blotting: Paired with streptavidin-HRP or AP for enhanced sensitivity.
• Affinity Purification: For isolating proteins or complexes from samples.
• Immunohistochemistry: As a versatile tool with amplification steps.

Biotin conjugates are widely used due to their ability to provide amplification for applications that require high sensitivity. Boster Bio's catalog contains biotin-conjugated primary antibodies and secondary antibodies, and additional conjugate options. You can also learn more about our custom antibody conjugation service and book a meeting with us to discuss your project, so we can better serve your research needs. Submit an inquiry today!

Metal Conjugates

Metal conjugates, including lanthanide-chelated antibodies (e.g., Europium, Terbium) and metal isotope-tagged antibodies for mass cytometry (CyTOF), are gaining traction in advanced applications.

• Lanthanide-chelated antibodies (e.g., Europium, Terbium): These antibodies are used in time-resolved fluorescence assays.
• Metal Isotope-tagged antibodies for CyTOF (Mass Cytometry): Metal isotope-tagged antibodies allow high-dimensional analysis of cell populations.

Metal-conjugated antibodies are used in:

• Mass Cytometry (CyTOF): For high-dimensional analysis of cell populations, offering detailed phenotyping with minimal signal overlap.
• Multiplexed Immunoassays: Where lanthanides enable time-resolved fluorescence.

Growing popularity of metal conjugates, especially in advanced applications like CyTOF, reflects their capability to provide comprehensive cellular analysis.

Quantum Dot Conjugates

Quantum dot conjugates are semiconductor nanoparticles, including Qdot 525 and Qdot 655, known for their unique optical properties.

Quantum dot-conjugated antibodies are used in:

• Fluorescence Microscopy: For long-term imaging with high photostability.
• Multiplexed Imaging: Due to their broad excitation and narrow emission spectra.

Although less common than traditional fluorophores, quantum dots (Qdots) are increasingly popular in imaging applications for their photostability and distinct spectral properties.

Gold Nanoparticle Conjugates

Gold nanoparticles (AuNPs) are widely employed in various diagnostics, biosensing, and imaging applications.

Gold nanoparticle-conjugated antibodies are used in:

• Lateral Flow Assays: For rapid point-of-care testing (e.g., pregnancy tests).
• Electron Microscopy: For enhanced contrast in imaging.
• Biosensors: For detecting various analytes with stability and high sensitivity.

Gold nanoparticle-conjugated antibodies are quite popular in diagnostics and increasingly in biosensing applications due to their practical utility and ease of detection.

Conclusion

Antibody conjugates play a vital role in modern research, with each type offering distinct advantages. Fluorophore and enzyme conjugates remain staples due to their broad applications and established protocols. Biotin conjugates are favored for applications requiring high sensitivity, while metal conjugates offer advanced analysis capabilities. Quantum dots and gold nanoparticles, though more specialized, are expanding in use as techniques and technologies improve. Selecting the appropriate conj...

Flow cytometry and Fluorescence-Activated Cell Sorting (FACS) are indispensable tools in biomedical research and clinical diagnostics. Despite their widespread use, confusion often arises regarding their terminology and functionalities. In this article, we identify distinctions between flow cytometry and FACS, and discuss their principles and applications.

What is Flow Cytometry?

Developed in the 1950s and 1960s, flow cytometry revolutionized cell analysis by allowing rapid, high-throughput measurement of multiple cellular characteristics. This technique analyzes the physical and chemical characteristics of particles or cells in a fluid suspension, and involves passing a cell-containing fluid stream through a laser beam, measuring the scattered and fluorescent light emitted by the cells.

Key aspects of flow cytometry include:

• Principle: Flow cytometry utilizes lasers to analyze the physical and chemical properties of cells in a fluidic suspension by measuring scattered and emitted fluorescent light, providing multiparametric data on individual cells.
• Components: A typical flow cytometer comprises a fluidics system for sample flow control, lasers for excitation, optical detectors for light
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In this article, you will find the materials needed to draw a standard curve, the process of drawing a standard curve, and how to utilize it.

What Is IHC Staining?

Immunohistochemistry (IHC) is a vital technique in biomedical research and clinical diagnostics, enabling the visualization and localization of specific proteins within tissue samples. In this blog, we outline the different types of IHC staining, including direct and indirect...