With years of experience in the pharmaceutical and life science sector, CD Bioparticles now launches MagIso™ DNA & RNA Magnetic Silica Particles for rapid and reliable isolation of nucleic acid from plant tissues, whole blood, serum, plasma, buccal swabs, saliva, bacteria, plasmids, forensic samples and other body fluids.

CD Bioparticles offers a comprehensive list of basic, coated, functional and conjugated silica particles with uniform size and shapes. These silica particles in the size range of 10 nm to 1.5 µm are monodisperse and nonporous particles with a density of 2.0 g/cm³, while particles between 3 and 20 µm are porous particles with a density of 1.8 g/cm³. These silica particles can be used in protein adsorption and separation, nucleic acid detection and purification, drug and gene delivery, imaging contrast agents construction, and theranostics platform.

The new MagIso™ DNA and RNA Magnetic Silica Particles consist of a magnetic core encapsulated in a polymer matrix and a silica coating with terminal functional groups for excellent magnetic properties. They can be easily adapted to a magnetic nucleic acid extraction instruments to achieve automated high-throughput, high-purity extraction and purification of DNA/RNA. These magnetic particles have excellent magnetic properties and can be completely separated in just 3 seconds.

In addition, MagIso™ DNA & RNA Magnetic Silica Particles are flexible for manual or automated high-throughput DNA/RNA isolation, and have stable suspensions, with long gravity settling time/low sedimentation rate, about 30 min. CD Bioparticles ensures fast magnetic response (only 3 seconds for complete separation) and high yields, with up to 10 µg of genomic DNA from 200 µL of whole blood. The isolated DNA is immediately ready-to-use in downstream application such as sequencing, in vitro transcription, restriction enzyme digestion, or transfection of robust cell lines.

“CD Bioparticles is very excited to introduce these new silica particles to the research community. With such innovative particles, your reproducible results and lot to lot consistency can be CV < 5%,” said Dr. Robin J. Watts, the scientific officer of R&D department of CD Bioparticles. “It demonstrates CD Bioparticles’ commitment to advance the research process and improve study outcomes for customers and scientists. We will continue to expand our portfolio to provide more innovative offerings to better support our clients.”

CD Bioparticles provides the most comprehensive list of nanoparticles products with different sizes and surface properties to meet scientists’ needs in both research and industrial development. For more detailed information about MagIso™ DNA & RNA Magnetic Silica Particles or to discuss your project, please visit CD Bioparticles at https://www.cd-bioparticles.com.

About CD Bioparticles

CD Bioparticles is a global leading manufacturer and supplier of various nanoparticles, microparticles and their coatings for R&D and commercialization in a wide variety of application areas including in vitro diagnostics, biochemistry, cellular analysis, cell separation, and immunoassay. It also offers various custom services including chemical surface-functionalized, fluorescent modification, antibody immobilization, nucleic acid and oligo conjugation to meet clients’ specifications.

CD Bioparticles Launches New Silica Particles for Magnetic Nucleic Acid Extraction

An international team of researchers has discovered the first human antibody that effectively neutralizes two types of hantaviruses in animal models, according to a study published online in the journal Science Translational Medicine. Based on their preliminary results, the antibody appears to be a promising candidate for the development of a "pan-hantavirus" therapy that could prevent outbreaks caused by multiple known or emerging hantaviruses. The title of this paper is “Human antibody recognizing a quaternary epitope in the Puumala virus glycoprotein provides broad protection against orthohantaviruses”. 

Rodent-borne orthohantaviruses transmitted by rodents are zoonotic viruses with global distribution that cause hantavirus cardiopulmonary syndrome (HCPS) or hemorrhagic fever with renal syndrome (HFRS). Rodent-borne Hantaviruses are divided into two distinct virus families, commonly referred to as "Old World" and "New World" Hantaviruses. HFRS is caused by Old World viruses primarily found in Europe and Asia, while New World viruses cause HCPS, commonly found in North and South America. 

The hantavirus causes about 50,000 serious and often fatal infections worldwide each year. While humans are usually infected through contact with rodents, the virus can also be spread through direct human-to-human contact. Currently, there is no FDA-approved vaccine or antiviral therapy to prevent or treat the serious and potentially fatal disease caused by the emerging hantavirus.

In a previous study, Mitler et al. describe the isolation of human monoclonal antibodies (mAbs) directed against the hantavirus Puumala virus (PUUV) spike protein complex from PUUV-experienced donors recovered from HFRS. This set of 135 mAbs exhibited different cross-reactivity and neutralizing activities against viruses from different hantavirus clades and targeted different parts of the viral spike. The mAb ADI-42898 blocked viral entry of seven different hantaviruses and protected Syrian hamsters challenged with HCPS-causing Andes virus or bank voles challenged with HFRS-causing PUUV. These findings suggest that monoclonal antibodies may have utility in the treatment of hantavirus disease.

Now in this new study, the researchers describe the isolation of human neutralizing antibodies (nAbs) against tetrameric Gn/Gc glycoprotein spikes from PUUV-experienced donors. They define a dominant class of nAbs recognizing the “capping loop” of Gn that masks the hydrophobic fusion loops in Gc. A subset of nAbs in this class, including ADI-42898, bound Gn/Gc complexes but not Gn alone, strongly suggesting that they recognize a quaternary epitope encompassing both Gn and Gc. ADI-42898 blocked the cell entry of seven HCPS- and HFRS-associated hantaviruses, and single doses of this nAb could protect Syrian hamsters and bank voles challenged with the highly virulent HCPS-causing ANDV and HFRS-causing PUUV, respectively. ADI-42898 is a promising candidate for clinical development as a countermeasure for both HCPS and HFRS, and its mode of Gn/Gc recognition informs the development of broadly protective hantavirus vaccines.

The authors of the paper expressed that this is the first monoclonal antibody to demonstrate cross-protective efficacy against distinct Old and New World hantaviruses. According to the authors, hantavirus outbreaks in Sweden, Argentina and the United States over the past two decades highlight the public health risks posed by these viruses. The frequency of these and other emerging disease outbreaks is expected to increase with loss of animal habitat and climate change.

Reference

1.Mittler, Eva, et al. Human antibody recognizing a quaternary epitope in the Puumala virus glycoprotein provides broad protection against orthohantaviruses. Science Translational Medicine. 2022. eabl5399.

Research Finds Antibodies Show Promise for Treatment of Hantavirus

As a global leading supplier of raw materials, antibodies, and reagents for bio-technology industry, Creative Diagnostics recently launches recombinant antigens p18 and p23 (viral capsid antigens, VCA), p54 and p138 (early antigens, EA) and EBNA1 (nuclear antigen, EBNA). These recombinant antigens in immunoassays are suitable for the detection of IgG and IgM antibodies against EBV in blood samples.

Epstein-Barr Virus (EBV) is one of the most prevalent human viruses, as it affects more than 90% of adults in the world. Blood tests for EBV detect antibodies against EBV in the blood and help establish a diagnosis of EBV infection. Creative Diagnostics now offers several new products for EBV research uses, such as Recombinant EBV p18 (DAGA-3074, the E.Coli derived recombinant mosaic protein contains the HHV-4 p18 regions, and 1-119 amino acids), Recombinant Epstein-Barr Virus p54 Early Antigen [His] (DAG-T2771, a DNA sequence encoding the Epstein-Barr virus p54 early antigen (a.a 257-404) was expressed with a polyhistidine tag at the N-terminusl), and EBV NA protein [His] (DAG1578, the Recombinant EBV NA protein fused to His Tag at N-terminus was expressed in E. coli and purified by proprietary chromatographic technique).

Epstein-Barr virus, also known as human herpesvirus 4 (HHV4), belongs to Gammaherpesviridae, the genus Lymphovirus. EBV is spread through saliva, blood, and semen, and usually causes infectious mononucleosis (IM). Some cases also show that the virus links to several types of cancer and have a higher risk of certain autoimmune diseases. EBV has the ability to infect a very broad age group. In the United States, about half of five-year-olds and about 90 percent of adults have evidence of prior infection. The main cell types of EBV infection are epithelial cells and B cells. Once the initial lytic infection of EBV is controlled, EBV latency persists in an individual’s B cells for the rest of the individual’s life.

EBV-specific serological assays, such as ELISA, EIA, IFA, chemiluminescence, and immunoblot, are the easiest methods to test for EBV infection and to assess acute and distant infection in healthy individuals. Among the proteins encoded in the EBV genome, several have been used to detect EBV antibodies, including EBNA1, EBNA2, VCAp23, VCAp18, early antigens. Commercial immunoassays for the detection of IgG and IgM against EBV are required to detect at least three EBV antibodies: VCA-IgG, VCA-IgM, and EBNA-1 IgG, which are often combined to differentiate between acute and distant infections. The presence of VCA IgM and VCA IgG without EBNA-1 IgG indicates current acute infection, whereas the presence of VCA IgG and EBNA1 IgG in the absence of VCA IgM usually indicates distant infection.

If you want to know more details about antigens for EBV antibody tests or have any other questions about our research materials, please visit Creative Diagnostics at https://www.creative-diagnostics.com.

About Creative Diagnostics

Creative Diagnostics is a leading manufacturer and supplier of antibodies, viral antigens, innovative diagnostic components and critical assay reagents. It also provides contract biologic R&D and manufacturing services to the diagnostic manufacturers along with GMP biologics manufacturing for the biopharmaceutical market. It aims to provide a trusted source for all researchers’ assay development and manufacturing needs.

Creative Diagnostics Announces Antigens for Epstein-Barr Virus Antibody Tests

We used stimulation with anti-IgE or IL-3 in whole blood, which would allow for the potential interaction of multiple cell types under conditions that simulate an allergic response. 

One milliliter aliquots of whole blood were distributed into round-bottom tubes with loose lids and warmed in a 37°C water bath for 30 seconds. Freshly prepared, 1 mL aliquots of pre-warmed RPMI 1640 (Gibco) were supplemented with polyclonal rabbit anti-IgE (Bethyl Laboratories) or IL-3 (PeproTech). The prewarmed 1 mL of whole blood was then mixed with either 1 mL of RPMI 1640, or RPMI 1640 supplemented with anti-IgE (final concentration, 1 μg/mL) or IL-3 (final concentration, 2 ng/mL) and incubated for 30 minutes at 37°C in a 5% CO2 incubator. After the incubation period, red blood cells were removed by hypotonic lysis with 20 mL of cold RBC lysis buffer (BioLegend) and incubation for 15 minutes on ice. The lysis reaction was stopped with PBS supplemented with EDTA (Invitrogen Life Technologies; final concentration, 2 mM) followed by centrifugation at 250g for 5 minutes at 4°C (all centrifuge runs on live cells were done with these conditions).

*Blood was stored at most 24h at 4 deg C

*Anticoagulant EDTA or heparin can have distinct impact on basophil activation profiles

*We chose to use whole blood vs. cells post red blood cell lysis because we wanted to retain as close of an environment as that in situ

*Must use sterile techniques

*If followed by mass cytometry analysis vs flow cytometry, watch out for metal contamination. Must use low barium PBS, avoid glass bottles 

Stimulation of basophils + a bunch of other cells in vitro

DNA stains enable a commonly used FACS method of monitoring a compound’s effects on cell cycle progression. 


1. Transfer cells from culture dishes to FACS tubes. Make sure you pipet vigorously to get all the lightly adherent cells. The protocol assume 0.5 million cells per sample, so scale up or down with the volumes for your samples. 

2. If needed, stain for surface antigens.

3. Spin cells for 5 minutes, 500 g in a microcentrifuge. Discard supernatants afterwards.

4. Resuspend the cell pellet in 250 uL wash buffer (1x PBS with 5mM EDTA). 

5. Add 125uL 100% COLD ethanol and vortex immediately. Repeat once. 

6. Incubate at room temperature for at least 30 minutes. This cell suspension can be left at 4 C overnight instead if necessary.

7. Spin cells at 5 min, 500 g. Discard supernatants afterwards.

8. Add 250 uL propidium iodide solution (0.1 mg/ml propidium iodide in wash buffer). Place samples on ice.

9. The exact parameters and protocol at this point are dependent on your flow cytometer, but in general start with gating out cell debris using SSC/FSC and doublets using FL2-H/FL2-W. PI has an excitation wavelength of 488nm and maximal emission at 617nm.

10. Collect at around 10,000 events at low speed settings using cell count vs FL2-H as the primary indicator of cell cycle. There will be 2 primary peaks representing G0/G1 and G2 phase respectively, with the G2 phase having double the FL2 height due to having twice the amount of DNA. Cells with less FL2 height than the G1 population are sub-G1 (dying) and cells in between the two main peaks are in the S phase.

Cell Cycle Progression Analysis

A commonly used quantifiable metric for protein phosphorylation is achieved through the use of fluorescence tagged antibodies specific for phosphorylated protein sites. Post treatment cell samples incubated with these antibodies can be analyzed via flow cytometry to measure their respective levels of phosphorylation. Be sure to include unstained controls and secondary antibody only controls if necessary.


1. Treat 0.5-2x106 cells per condition for 2-3 hours.

2. Collect cells to conical tubes / eppitubes and spin down cells (500g, 5 minutes).

3. Prechill 810µl Methanol in -20 C freezer.

4. Resuspend pellet in 100µl PBS (does not have to be sterile).

5. Add 100µl of 4% paraformaldehyde (PFA)  -or-  25µl of 16% PFA to each sample.

6. Incubate 10 min at room temperature.

7. Add 800µl of ice cold methanol 100% methanol. At this stage, you can store at -20oC indefinitely or incubate samples for 30 minutes before proceeding to the next step.

8. Spin down cells 12,000rpm, 5min. This spin should be as fast as possible to ensure maximum sample collection.

9. Add 1 ml PBS to each sample.

10. Spin down cells 12,000rpm, 5min.

11. Prepare 100 uL of primary antibody master mix per sample. Concentrations may need to be 2-5 times higher than an equivalent western blot procedure.

12. Discard sample supernatant and add 100µl of diluted antibody in PBS. 

13. Incubate 30 minutes in the dark on ice (or a fridge).

14. Wash by adding 1 mL PBS and incubate for 5 minutes at room temperature. Spin down cells at 8000 rpm, 5 minutes. Prepare secondary antibody solution in the meantime if necessary (100 uL solution per sample).

15. Remove supernatant. If using secondary antibody repeat resuspension, incubation, and wash steps with secondary antibody solution. If proceeding to FACS analysis, resuspend in 250 uL PBS.

16. Analyze via FACS.

Phosphoflow Protocol

The scientist with profound knowledge gained from a multinational and multidisciplinary career in top research institutions with expertise in innate immunity and immunology, virology, cancer, and skin biology. Leading a group for the development of the three-dimensional skin, cancer, and immunology platforms. Established novel approaches in drug discovery in skin care-related products. Experience in scientific writing, project development, and management.  PI on NIH SBIR grant.

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