Blog Archives - Quanta BioDesign

Figure 1: Aminooxy-dPEG®11-azide HCl, product number 10538, is Quanta BioDesign's newest click chemistry crosslinker.

Aminooxy-dPEG^®₁₁-azide: A New Click Chemistry Crosslinker

Quanta BioDesign, Ltd. is proud to announce that our newest click chemistry crosslinker, Aminooxy-dPEG®11-azide∙HCl, product number 10538, is available for sale. This crosslinker combines carboxyl reactivity via an aminooxy group and alkyne reactivity through an azide group. See Figure 1 for the…

This reaction scheme shows how to use Quanta BioDesign's product number 10524, Azido-dPEG®11-amine, as a click chemistry crosslinking reagent. In the scheme, the amine end of molecule is reacted with a carboxylate group forming an amide bond with R1. Subsequently, the azide end of the molecule reacts by click chemistry (either copper(I)-catalyzed or strain-promoted azide-alkyne cycloaddition) to crosslink R1 with R2.

Three Click Chemistry Crosslinking Ideas with dPEG^®

Have you ever been working your way through a product catalog when you've come across a product you weren't sure how to use? I know I have. In those "What do I do with this?" moments, tips that explain how…

Figure 2: General chemical structure of Quanta BioDesign's DBCO-dPEG® TFP ester products for crosslinking azides and amines.

Copper-free Click Chemistry to Crosslink Azides and Amines

Quanta BioDesign's monodispersed, discrete PEG (dPEG®) products include a wide range of useful tools for click chemistry. Most of our reagents are designed to enable copper-free click chemistry, which is essential for biocompatible labeling and crosslinking. Copper-free click chemistry that…

Welcome to Our New Look!

March 3, 2020
QuantaBioDesign
Blog

Welcome to Our New Look! Welcome to Quanta BioDesign's new website! If you are a new visitor to our site, welcome! We are always glad to have new visitors. Quanta BioDesign, Ltd. makes and sells single molecular weight (i.e., monodispersed)…

Title Slide of Paul Davis' talk at the 7th Annual World ADC Summit in San Diego, given October 11, 2016. The talk is titled "Using the dPEG as the Framework to Uniquely Load and Protect Payloads in an ADC Format with dPEG Single Molecule Precision"

Our World ADC 2016 Presentation

The World ADC Summit in San Diego was held October 10-13, 2016. This was the 7th Annual World ADC Summit. On October 11, 2016, our company president, Paul D. Davis, presented his talk titled, “Using the dPEG^® as the Framework to Uniquely Load and Protect Payloads in an ADC Format …with dPEG^® single molecule precision.”

Graph showing the relationship of dPEG® linker length in relation to potency and specificity in extracellular drug conjugates.

Extracellular Drug Conjugates Therapeutically Exploit Protein Proximity

Pharmaceutical company Centrose, founded by James R. Prudent, Ph.D., developed a new class of antibody drug conjugates called extracellular drug conjugates. Nature Publishing Group published the research as a open access paper in its Molecular Therapy journal.¹ Apart from the interesting and important development of a new class of antibody drug conjugate (ADC), the research also showed how important linker length ² is to the potency and specificity of the EDC.

Amphotericin B conjugated to a discrete PEG (dPEG®) linker with a free amine have higher water solubility and lower toxicity than the parent compound.

Amphotericin B+dPEG®: Water-Soluble, Less Toxic, Potent

March 29, 2016
QuantaBioDesign
Blog, Literature Reviews, Product Reviews

About Amphotericin B

Structure of Amphotericin B. Used with permission from J. Med. Chem. (2016), 59, 1197-1206, copyright 2016, American Chemical Society. — **Figure 1:** Structure of Amphotericin B. Image used by permission from J. Med. Chem. (2016), 59, 1197-1206, copyright 2016, American Chemical Society.

Amphotericin B (Figure 1) is the “gold standard” treatment for systemic fungal infections and diseases caused by the parasite Leishmania. Sometimes it is the only effective treatment because drug resistance renders other treatments useless. Systemic fungal infections are an increasingly serious, widespread problem in medicine. Patients with weakened or suppressed immune systems (caused by HIV/AIDS, diabetes, organ transplants, some cancer treatments) are especially at risk. An estimated 1.5-2 million people die each year from systemic fungal infections (1). Despite its “gold standard” label, there are several difficulties with Amphotericin B.

Figure 1 shows the process of membrane fusion as mediated by the SNARE protein complex.

SNARE-Mediated Membrane Fusion and dPEG^®, Part 3

Part 3: Modeling Membrane Fusion with SNARE Protein Analogs

Click the links for Part 1 and Part 2 of this three-part series.

Figure 1: Structure of the DOPE-PEG12-LPE/LPK lipidated oligopeptides used to study liposome fusion.

SNARE-Mediated Membrane Fusion and dPEG®, Part 2

Part 2: Controlling Liposome Fusion Using SNARE Protein Mimics

For Part 1 of this three-part series, click here. For part 3, click here.

Chemical structure of PN10283, Fmoc-N-amido-dPEG®12-acid

SNARE-Mediated Membrane Fusion and dPEG®, Part 1

Part 1: A Reduced SNARE Model for Membrane Fusion

The cells of all living things depend on membrane fusion for intra- and intercellular transport of molecules. In both cellular membrane fusion and intracellular vesicle fusion, the fusion process is controlled and guided by SNARE proteins. SNARE is an acronym for Soluble NSF Attachment Protein Receptor. NSF stands for N-ethylmaleimide-Sensitive Factor. Reviews of SNARE protein structure and function can be found here, here, here, and here. An example of a SNARE protein is synaptobrevin. Click part 2 and part 3 to read the other pieces in this series.