Quanta BioDesign is a research and manufacturing company committed to the development of a full range of discrete polyethylene glycol (dPEG®) PEGylation reagents for applications in diagnostics, therapeutics, peptide synthesis, oligonucleotide synthesis, and nanotechnology.

Quanta BioDesign’s vision incorporates a dedicated commitment to producing the most useful compounds for your current and future applications and needs using synthetic and process technology that allows the most economic incorporation of these products into your application.

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What is dPEG®?

The term “dPEG®” is Quanta BioDesign’s trademarked acronym for “discrete polyethylene glycol” or “discrete PEG”. The “discrete” portion of the dPEG® trademark indicates single molecular weight PEG technology. Like traditional PEGs, our products contain an amphiphilic[1] backbone of repeating ethylene oxide units. However, traditional PEGs are not single compounds. Quanta BioDesign invented and manufactures these monodisperse PEG products using our proprietary synthetic and purification processes.

What is PEGylation?

PEGylation is the process adding polyethylene glycol (PEG) to a molecule or surface, often through covalent modification of the targeted molecule or surface. Molecules and surfaces that have been modified by PEGylation are called PEGylated. Any surface containing appropriate functional groups can be PEGylated. Gold, silver, iron, and silica are examples of surfaces that are often PEGylated for use in diagnostic, therapeutic, or theranostic applications. The list of molecules that are PEGylated is enormously long and continually expanding. Examples of the types of molecules that are PEGylated include small molecule therapeutic drugs, peptides, proteins, the carbohydrate coats of glycoproteins, oligonucleotides, and lipids.

The benefits of PEGylation include increased water solubility, increased hydrodynamic volume, decreased immunogenicity, and extended circulation in vivo in the bloodstream due to reduced renal clearance. In addition to reducing renal clearance, PEGylation also often modifies the biodistribution and pharmacokinetics of therapeutic, theranostic, and diagnostic molecules.

Traditional PEGs

Specifically, traditional PEG products are prepared by polymerization processes. Any polymerized PEG product is a Poisson distribution of chain lengths and molecular weights.[2],[3] This distribution was formerly known as the polydispersity index (PDI), but is now known as the dispersity index or simply dispersity (indicated by the symbol “Đ”)[4]. The reported molecular weight is an average molecular weight, and Đ (or PDI) gives an indication of the range of molecular weights in the sample. Disperse samples have Đ > 1 and are a heterogeneous mixture of sizes and molecular weights. High M.W. (>50 kDa) traditional PEG has Đ up to 1.1. Lower M.W. traditional PEG has Đ in the range of 1.01 – 1.05. These numbers represent broad distributions of molecular weights.[5],[6],[7]

dPEG® Products Are Different

Our dPEG® products are quite different from traditional PEGs, because of our proprietary, patent-protected processes. Each dPEG® product represents a single compound with a unique, specific, single molecular weight (MW). See Figure 1.

Figure 1

Figure 1: Side-by-side comparison of actual mass spectra from a traditional, dispersed PEG (left spectrum) and a dPEG® of equivalent mass from Quanta BioDesign (right spectrum). The mass spectrum on the left is of PEG1000. It has Mw = 1027 Daltons; Mn = 888 Daltons; and Đ = 1.16. The masses in this dispersed PEG range from 600 – 1,500 Daltons. The mass spectrum on the right is of Quanta BioDesign product number 10317, amino-dPEG®24-acid, the structure of which is shown across the top of the two mass spectra. PN10317 is a single molecular weight compound with a single, discrete chain length. The molecular weight of PN10317 is 1146.355 Daltons. Because it has no dispersity, Đ = 1.

A Wide Variety of Functional Groups and Architectures for dPEG® Products

Our dPEG® products are synthesized from high purity building blocks (e.g. diethylene glycol, triethylene glycol, or tetraethylene glycol) in a series of stepwise reactions to provide specific MWs, organic moieties, functional groups (see Figure 2), and architectures (see Figure 3) suited for a wide variety of applications. From these building blocks, we produce homobifunctional and heterobifunctional crosslinkers, homotetrafunctional and homohexafunctional crosslinkers, biotinylation reagents, fluorescent tags, surface modification reagents, and specialized products designed for modification of pharmacokinetics (PK) and biodistribution (BD). Our products contain methoxy, alcohol, and carboxylic acid end-capping; various protective groups for reactive moieties (e.g., methoxytrityl, Fmoc, boc, etc.); various functional groups for conjugation to amines, thiols, alcohols, carboxylic acids, ketones, aldehydes, alkynes, and azides; and a wide variety of organic moieties (i.e., biotin, lipoamide, fluorescein, DOTA, etc.).

Figure 2: Examples of the functional, reactive, labeling, and protective groups on dPEG® products.

Figure 3: Available architectures for dPEG® products. Branched dPEG® products can have three (3) or nine (9) branches. Our Sidewinder™ products are a new class of dPEG® constructs that offer a broad range of new ways to incorporate dPEG® functionality into diagnostic and therapeutic applications.

All dPEG® products contain linear chains of two to seventy-two ethylene oxide units. We also build branched structures consisting of three to nine of these linear chains. Our proprietary synthetic processes maintain homogeneity of our products in the range of 200 Da to 16 kDa. Our Sidewinder™ line of products was designed by Quanta BioDesign’s scientists to provide new ways to incorporate the beneficial properties and advantages of dPEG® products into diagnostic and therapeutic applications. One clear application for these products is fine-tuning PK and BD of diagnostic and therapeutic products. These novel dPEG® products are not possible with traditional disperse PEG products.


[1] The term “amphiphilic” means that the compound is soluble in both water (or aqueous buffer) and organic solvents. All PEG products that do not contain hydrophobic substituents are soluble in water and in a variety of organic solvents. The addition of hydrophobic groups to PEG reduces the water solubility of some PEG products.

[2] Flory, P. J. Molecular Size Distribution in Ethylene Oxide Polymers. J. Am. Chem. Soc. 1940, 62, 1561−1565. https://doi.org/10.1021/ja01863a066.

[3] Herzberger, J.; Niederer, K.; Pohlit, H.; Seiwert, J.; Worm, M.; Wurm, F. R.; Frey, H. Polymerization of Ethylene Oxide, Propylene Oxide, and Other Alkylene Oxides: Synthesis, Novel Polymer Architectures, and Bioconjugation. Chem. Rev. 2016, 116, 2170-2243. https://doi.org/10.1021/acs.chemrev.5b00441.

[4] Gilbert, R. G.; Hess, M.; Jenkins, A. D.; Jones, R. G.; Kratochvíl, P.; Stepto, R. F. T. Dispersity in polymer science (IUPAC Recommendations 2009). Pure Appl. Chem. 2009, 81, 351–353. https://doi.org/10.1351/PAC-REC-08-05-02. See also, Stepto, R. F. T. Erratum. Pure Appl. Chem. 2009, 81, 779. https://doi.org/10.1351/PAC-REC-08-05-02_erratum.

[5] Veronese, F. M.; Mero, A.; Pasut, G. Protein PEGylation, Basic Science and Biological Applications. In PEGylated Protein Drugs: Basic Science and Clinical Applications; Veronese, F. M., Ed.; Milestones in Drug Therapy; Birkhäuser Basel: Basel, 2009; pp 11–31. https://doi.org/10.1007/978-3-7643-8679-5_2.

[6] Jevsevar, S; Kunstejl, M; Porekar, V.G. PEGylation of therapeutic proteins. Biotechnology Journal 2010, 5(1) 113-128. DOI: 10.1002/biot.200900218.

[7] For example, dextran with Đ=2 is considered “low dispersity” today. Previously dextran had even higher dispersity than that. See, Pasut, G. Polymers for Protein Conjugation. Polymers 20146(1), 160–178. https://doi.org/10.3390/polym6010160.

The dPEG®-Biotin Advantage

Biotinylation is one of the most widely used bioconjugation techniques. It can add a biotin tag to antibodies, proteins, and other molecules for high-affinity binding with streptavidin reagents. Our dPEG® spacers create a significant advantage over aliphatic biotin compounds, such as the popular NHS-LC-biotin reagent. The SuperHydrophilic™ dPEG® spacers prevent antibody or protein denaturation, aggregation, or precipitation, which is often a problem when using hydrophobic biotinylation compounds. Discover the dPEG® difference with our water-soluble biotinylation reagents and our wide selection of conjugation chemistries.

• Amine Reactive dPEG® Biotinylation Reagents
• Biotin-dPEG®x-azide for Click Chemistry
• Biotinidase Resistant Biotin
• Carbonyl Reactive dPEG® Biotinylation Reagents
• Other dPEG® Biotinylation Reagents
• Photoaffinity dPEG® Biotinylation Reagent
• Thiol Reactive dPEG® Biotinylation Reagents

Product CodeNameCAS
10784Biotin-dPEG®₁₁-azidedPEG®: 2276672-04-7; Polymer: 956494-20-5
10201Biotin-dPEG®₃-MALdPEG®: 1263044-71-8; Polymer: 525573-2-2
10195Biotin-dPEG®₁₁-MALdPEG®: 1646619-56-8; Polymer: 1334172-60-9
10193Biotin-dPEG®₃-NH₃+TFA-dPEG®: 194920-43-9; Polymer: 1334172-59-6
10196Biotin-dPEG®₁₁-NH₂dPEG®: 2407913-93-1; Polymer: 604786-74-5
11100Biotin-dPEG®₃-oxyamine. HCl1951424-88-6
11102Biotin-dPEG®₁₁-oxyamine. HClN/A
10308Biotin-dPEG®₃-TFPAdPEG®: 1263044-14-9; Polymer: 1264662-85-2
10356Biotinoyl-2-Aminobutyric aciddPEG®: 1263044-15-0; Polymer: 917015-56-6
10325Bis-dPEG®₃-biotindPEG®: 1263044-47-8; Polymer: 194920-54-2
10199dPEG®₄-biotin aciddPEG®: 1263044-75-2; Polymer: 721431-18-1
10197dPEG®₁₂-biotin aciddPEG®: 1621423-14-0; Polymer: 948595-11-7
10773dPEG®₂₄-biotin acidN/A
10776dPEG®₄₈-biotin acidN/A
10205NHS-biotindPEG®: 85718-04-3; Polymer: 35013-72-0
10198NHS-dPEG®₁₂-biotindPEG®: 1934296-88-4; Polymer: 365441-71-0
10202NHS-dPEG®₄-biotinidase resistant biotin1334172-61-0
10194NHS-S-S-dPEG®₄-biotin (cleavable)1260247-51-5
10203TFP-dPEG®₄-biotinidase resistant biotinN/A
10204TFP-dPEG®₁₂-biotinidase resistant biotinN/A
10009Biotin-dPEG®₄-TFP esterN/A
10008Biotin-dPEG®₁₂-TFP esterN/A
10007Biotin-dPEG®₂₄-TFP esterN/A

dPEG® Modification

Discover the dPEG® difference with our broad range of architectures and functional and reactive groups for the chemical modification of small molecules, biomolecules, and nanoparticle surfaces. Improve biocompatibility and increase the water solubility of hydrophobic molecules by adding a discrete dPEG® modifier. Use hydrophilic dPEG® thiolation reagents to create thiols for conjugation. Modify with branched-chain dPEG® reagents to change pharmacokinetics. Coat particle or planar surfaces with dPEG® modification reagents to create functionality and mask underlying hydrophobicity.

• Amine Reactive dPEG® Reagents
• Branched dPEG® PK Modifiers
• Carboxyl and Active Ester Reactive dPEG® Reagents
• dPEG® Thiolation Reagents: Converting an Amine to a Protected Thiol
• Metal Surface dPEG® Modification Reagents
• Other Reactivities for dPEG® Modifications
• Reagents to Extend Carboxyl with dPEG® Spacers
• SuperHydrophilicTM dPEG® Chemical Modification Reagents
• Thiol Reactive dPEG® Modification Reagents

dPEG® Click Reagents

Whether you need dPEG® compounds for strain-promoted (SPAAC), copper-catalyzed (CuAAC), or ruthenium-catalyzed (RuAAC) reactions, your click chemistry is enabled as never before by our water-soluble, non-immunogenic dPEG® products. Even hydrophobic cyclooctyne compounds are made more hydrophilic by incorporating SuperHydrophilic™ dPEG® linkers. Click now to empower your chemistry!

• Click dPEG® Azide Crosslinkers
• Click dPEG® Biotinylation Reagents
• Click dPEG® Terminal Alkynes
• Click dPEGylation® Reagents
• Click Fluorescent Dyes
• Copper-Free Click dPEG® Crosslinkers
• Crosslinkers: dPEG® Alkynes
• DBCO-dPEG® Reagents – Hydrophilic Copper-Free Click Reagents

dPEG® Conjugation Reagents:

The process of bioconjugation often uses reactive crosslinkers to couple two molecules together through a crossbridge or linker arm. The use of traditional aliphatic crosslinkers can add unwanted hydrophobicity to modified biomolecules and cause aggregation and nonspecific interactions. By contrast, crosslinking reagents made with our novel, hydrophilic dPEG® groups produce water-soluble compounds, which create conjugates having greater biocompatibility and extremely low nonspecific binding properties.

Our selection of dPEG® crosslinkers includes homobifunctional, heterobifunctional, and branched chain architectures with a wide variety of reactive groups. All of the crosslinkers contain our single molecular weight dPEG® chains as crossbridges. The choice of dPEG® spacers can span molecular lengths from 2 to 48 ethylene glycol repeating units to satisfy virtually any application.

• Heterobifunctional Reagents: Amine and Thiol Reactive dPEG® Reagents
• Heterobifunctional Reagents: dPEG® Reagents for Hydrazone Bond Formation
• Heterobifunctional: Monoprotected dPEG® Reagents
• Homobifunctional Reagents: Amine Reactive dPEG® Reagents
• Homobifunctional: Diamine and Monoprotected Diamine dPEG® Reagents
• Homobifunctional: Thiol Reactive dPEG® Reagents
• Homohexafunctional: Thiol Reactive dPEG® Reagents
• Homotetrafunctional: Thiol Reactive dPEG® Reagents
• Other Thiol Reactive

Product CodeNameCAS
10109Acid-dPEG®₅-NHS ester1343476-41-4
10119Acid-dPEG®₉-NHS ester1895916-27-4
10724Bis-dPEG®₂-NHS ester65869-63-8
10726Bis-dPEG®₃-NHS ester1314378-16-9
10224Bis-dPEG®₅-NHS ester756526-03-1
10988Bis-dPEG®₇-NHS ester1334170-02-3
10246Bis-dPEG®₉-NHS ester1008402-79-6
10954Bis-dPEG®₁₃-NHS esterdPEG®: 2221949-00-2; Polymer: 1008402-79-6
10979Bis-dPEG®₁₇-NHS esterdPEG®: 2221948-93-0; Polymer: 1008402-79-6
10981Bis-dPEG®₂-PFP ester1314378-18-1
10956Bis-dPEG®₂₁-NHS esterdPEG®: 2221948-98-5; Polymer: 1008402-79-6
10968Bis-dPEG®₂₅-NHS esterdPEG®: 2221948-96-3; Polymer: 1008402-79-6
10982Bis-dPEG®₃-PFP ester1314378-13-6
10015Bis-dPEG®₅-PFP ester1334177-78-4
10237Bis-dPEG®₅, half benzyl half NHS ester1263044-84-3
10987Bis-dPEG®₇-PFP ester1334170-01-2
10967Bis-dPEG®₂₅-aciddPEG®: 2221948-96-3; Polymer: 1268488-70-5
10983Bis-dPEG®₉-PFP ester1334170-00-1
10631Bis-MAL-Lysine-dPEG®₄-TFP ester2173083-46-8
10232Bis-Maleimide amine,TFA salt1301738-40-8
11200Bromoacetamido-dPEG®₄-TFP ester2247993-78-6
11202Bromoacetamido-dPEG®₁₂-TFP esterN/A
11203Bromoacetamido-dPEG®₂₄-TFP esterN/A
10065MAL dPEG®₆-acid1334177-79-5
10285MAL-dPEG®₁₂-aciddPEG®: 2378428-27-2; Polymer: 871133-36-7
10266MAL-dPEG®₂-NHS ester955094-26-5
10549MAL-dPEG®₂-TFP ester1431291-44-9
10315MAL-dPEG®₂₄-aciddPEG®: 2171095-70-6; Polymer: 871133-36-7
10214MAL-dPEG®₄-NHS ester756525-99-2
10064MAL-dPEG®₆-NHS ester1137109-21-7
10274MAL-dPEG®₈-NHS ester756525-93-6
10284MAL-dPEG®₁₂-NHS esterdPEG®: 2101722-60-3; Polymer: 756525-92-5
10551MAL-dPEG®₄-TFP ester1807540-84-6
10556MAL-dPEG®₆-TFP esterN/A
10552MAL-dPEG®₈-TFP ester1924596-31-5
10553MAL-dPEG®₁₂-TFP esterN/A
10554MAL-dPEG®₂₄-TFP ester2384191-62-0
10555MAL-dPEG®₃₆-TFP esterN/A
11303MAL-dPEG®₂₄-amido-dPEG®₂₄-TFP esterN/A
10217MPS (NHS-3-maleimidopropionate)55750-62-4
10374SPDP-dPEG®₄-NHS ester1334177-95-5
10376SPDP-dPEG®₈-NHS ester1252257-56-9
10378SPDP-dPEG®₁₂-NHS ester924280-65-9
10379SPDP-dPEG®₂₄-NHS ester924280-65-9
10867SPDP-dPEG®₃₆-NHS ester924280-65-9
10177MPS-EDA.TFAdPEG®: 1301739-85-4; Polymer: 11550-02-00
10014Tris (2-carboxyethyl) phosphine hydrochloride (TCEP)51805-45-9
10085Bis-dPEG®₄-TFP ester1446282-42-3
10011Phthalimidooxy-dPEG®₄-NHS ester1415328-95-8
11135Phthalimidooxy-dPEG®₁₂-NHS esterN/A
10984Bis-dPEG®₁₃-PFP esterdPEG®: 1383567-59-6; Polymer: 1334170-00-1
10980Bis-dPEG®₁₇-PFP ester1334170-00-1
10985Bis-dPEG®₂₁-PFP ester1334170-00-1
10314MAL-dPEG®₂₄-NHS esterdPEG®: 2226733-37-3; Polymer: 756525-92-5
10172t-boc-N-amido-dPEG®₁₁-aminedPEG®: 1233234-77-9; Polymer: 198227-38-2
100814-formyl-benzamido-dPEG®₁₂-TFP esterN/A
10127Acid-dPEG®₁₃-NHS ester2152679-62-2
100824-formyl-benzamido-dPEG®₂₄-TFP esterN/A
10140Acid-dPEG®₂₅-NHS esterN/A
10092Bis-dPEG®₂₅-TFP esterN/A

dPEG® Fluorescent Dyes and Haptens

Dyes and hapten labeling reagents made with our SuperHydrophilic™ dPEG® compounds are revolutionizing the labeling of antibodies and other proteins. Traditional fluorescent dyes and haptens can be extremely hydrophobic, which can result in antibody instability, aggregation, and high nonspecific background in assays or detection applications.

Our growing line of dPEG®-modified fluorescent dyes changes everything. The addition of dPEG® tethers to the core dye structure results in extreme water solubility and biocompatibility for modified antibodies or other molecules. This means that you can label with more dyes for greater fluorescence intensity without causing antibody instability or nonspecific binding.

Our dPEG® dyes are brighter and display greater specificity toward targets than the previous generation of dyes. Revolutionize your labeled antibodies today with dPEG® Fluorescent Dyes and Haptens.

• Carboxyfluorescein-dPEG®₁₂-NHS ester
• DNP-dPEG®x-acid
• DNP-dPEG®x-NHS ester

Product CodeNameCAS
10885Carboxyfluorescein-dPEG®₁₂-NHS esterN/A
10347DNP-dPEG®₄-NHS ester858126-78-0
10399DNP-dPEG®₁₂-NHS ester1334178-01-6

dPEG® Delivery Reagents:

Quanta BioDesign’s line of payload delivery reagents includes three important product categories: DOTA-dPEG® bifunctional chelators, Phospholipid dPEG® derivatives; and our exclusive Sidewinder™ dPEG® constructs. Our DOTA products are useful for targeted radioimaging and radiotherapy applications with labeled antibodies. We designed the phospholipid category of products for use as liposomal and micellar drug delivery vehicles. In addition, our unique Sidewinder™ product line permits highly controlled construction of drug delivery systems with high drug-to-antibody ratios (DARs). With all of these delivery agents, “the dPEG® difference” provides enhanced hydrophilicity and biocompatibility so that modified antibodies retain stability and display low nonspecificity.

• DOTA-dPEG® Bifunctional Chelators with Adjustable Hydrophilic Linker Lengths
• Phospholipid dPEG® Derivatives
• Sidewinder™ dPEG® Constructs

Product CodeName
11153DOTA tris(TBE)-amido-dPEG®₂₃-bromo acetamide Sodium Bromide
11166DOTA-tris(TBE)-amido dPEG®₁₁-Maleimide
11160DOTA-tris(acid)-amido-dPEG®₄-TFP ester
11162DOTA-tris(acid)-amido-dPEG®₁₂-TFP ester
11163DOTA-tris(acid)-amido-dPEG®₂₄-TFP ester
11155DOTA-tris(TBE)-amido-dPEG®₄-TFP ester
11157DOTA-tris(TBE)-amido-dPEG®₁₂-TFP ester
11158DOTA-tris(TBE)-amido-dPEG®₂₄-TFP ester
11597MAL-[NH-dPEG®₄-Glu(TFP ester)]₃-NH-m-dPEG®₂₄
11626MAL-dPEG®₄-Glu(TFP ester)-NH-dPEG®₄-Glu(TFP ester)-NH-m-dPEG®₂₄
11581MAL-dPEG®₄-Glu(TFP ester)-NH-m-dPEG®₂₄

dPEG® Building Blocks:

Quanta BioDesign’s popular line of dPEG® building blocks provides SuperHydrophilic™ linkers of various molecular sizes and designs. The reagents contain reactive groups or protected functional groups for almost any application. They can be used to modify particles, create linker arms during peptide or oligonucleotide synthesis, or construct drug payload designs for antibody-drug conjugates (ADCs).

Our peptide modification products offers Cbz-, Fmoc-, and boc-protected amino-dPEG®x-acid compounds. Some of our Fmoc-protected products are available as preactivated (NHS or TFP esters) products. We also provide methoxytrityl-protected thiol compounds that permit conversion of an amine to a thiol and Fmoc-protected aminooxy products for customers who need to form oxime bonds. Finally, we offer two novel products that permit easy insertion of a biotin label into a peptide chain. Discover “the dPEG® difference” with Quanta BioDesign’s line of unique building blocks.

• Amino-dPEG®₁₂-ODMT
• CBZ-N-amido-dPEG®x-acid
• Fmoc-N-amido-dPEG®x-acid
• Fmoc-N-amido-dPEG®x-NHS ester
• Fmoc-N-amido-dPEG®x-TFP ester
• Fmoc-N-Lys-(dPEG®x-biotin)-OH-(acid)
• Methoxytrityl-S-dPEG®x-acid
• t-boc-N-amido-dPEG®x-acid

Product CodeNameCAS
11000Fmoc-N-amido-dPEG®₄-TFP ester2247993-77-5
11005Fmoc-N-amido-dPEG®₈-TFP esterN/A
11006Fmoc-N-amido-dPEG®₁₂-TFP esterN/A
11007Fmoc-N-amido-dPEG®₂₄-TFP esterN/A
11008Fmoc-N-amido-dPEG®₃₆-TFP esterN/A
10994Fmoc-N-amido-dPEG®₄-NHS ester1314378-14-7
10995Fmoc-N-amido-dPEG®₈-NHS ester1334170-03-4
10996Fmoc-N-amido-dPEG®₁₂-NHS esterdPEG®: 2227246-92-4; Polymer: 488085-18-3
10761t-boc-N-amido-dPEG®₁₂-aciddPEG®: 1415981-79-1; Polymer: 187848-68-6
10283Fmoc-N-amido-dPEG®₁₂-aciddPEG®: 1952360-91-6; Polymer: 756526-01-9
10313Fmoc-N-amido-dPEG®₂₄-aciddPEG®: 2170484-59-8; Polymer: 756526-01-9