GLUTARALDEHYDE (1,5-PENTANEDIAL)

Glutaraldehyde (1,5-Pentanedial), the linear C5 dialdehyde OHC(CH2)3CHO (CAS No 111-30-8, C5H8O2), is a homobifunctional, amine-reactive crosslinking agent and fixative supplied as aqueous solutions from a few percent up to 50 %, used in biochemistry, electron microscopy, enzyme and cell immobilisation, biomaterials and polymer science, and also as a disinfectant and biocide.
Glutaraldehyde is the preferred crosslinker in many laboratories because it reacts quickly with proteins under mild aqueous conditions, forms more stable and more extensive crosslinks than formaldehyde, penetrates tissue reasonably well and preserves fine structure at the electron-microscopic level.
Glutaral works through its two terminal aldehyde groups and their reactive oligomers, which condense with primary amino groups (mainly the epsilon-amino groups of lysine), form Schiff bases and Michael-type adducts, and bridge neighbouring molecules into a covalently linked network.

CAS No: 111-30-8
EC No: 203-856-5
Molecular formula: C5H8O2
Molecular weight: 100.12 g/mol
IUPAC name: Pentanedial
Structure: OHC-CH2-CH2-CH2-CHO
Supply forms: Aqueous solutions, for example 8 %, 25 % and 50 %
Solubility in water: Miscible (forms hydrates)

COMMON PRODUCT & CHEMICAL NAMES OF GLUTARALDEHYDE (1,5-PENTANEDIAL):

Glutaraldehyde (1,5-Pentanedial), Glutaraldehyde, 1,5-Pentanedial, Pentanedial, Pentane-1,5-dial, Glutaral, Glutaric dialdehyde, Glutaric aldehyde, Glutardialdehyde, Glutaric acid dialdehyde, 1,3-Diformylpropane, GA, GTA, Glutaraldehyde solution, Glutaraldehyde 25 % solution, Glutaraldehyde 50 % solution, Glutaraldehyde EM grade, Glutaraldehyde 8 % EM grade, Electron microscopy grade glutaraldehyde

The name 1,5-pentanedial describes the molecule directly: a five-carbon chain (pentane) with aldehyde groups (-al) on carbons 1 and 5. Glutaraldehyde comes from glutaric acid, the corresponding C5 dicarboxylic acid, glutaral is the INN and INCI name. 1,3-Diformylpropane is an older name that describes the same structure as a propane chain carrying two formyl groups. "EM grade" refers to purified, low-polymer solutions, often sealed under inert gas, for electron microscopy.
Pentanedial is different from glyoxal (ethanedial, C2), formaldehyde (methanal, C1) and ortho-phthalaldehyde (an aromatic dialdehyde). The length of the C5 chain is one reason why Glutaraldehyde (1,5-Pentanedial) behaves differently from these aldehydes as a crosslinker.

WHAT IS GLUTARALDEHYDE (1,5-PENTANEDIAL)?

Few reagents are as widely used for linking proteins as Glutaraldehyde (1,5-Pentanedial). It was introduced as a fixative for electron microscopy in 1963 and quickly became the standard primary fixative because it preserves cellular ultrastructure far better than formaldehyde alone. Since then, Glutaraldehyde (1,5-Pentanedial) has become a basic tool in protein chemistry, immunology, enzyme technology and materials science.
The reason is simple: Glutaraldehyde (1,5-Pentanedial) is small, soluble in water, cheap and highly reactive towards amino groups, and its reaction products are stable. With a single reagent, researchers can fix tissue, crosslink protein crystals, attach enzymes to carriers, make cross-linked enzyme aggregates, harden gelatin and chitosan, or link antibodies to enzymes.

At the same time, the chemistry of Glutaraldehyde (1,5-Pentanedial) is more complex than its simple formula suggests. Aqueous solutions contain several forms of the molecule, and the reactive species depend on pH, concentration, age and temperature. Understanding this chemistry helps users get reproducible results.

Fields where Glutaraldehyde (1,5-Pentanedial) is used as a crosslinker or fixative: transmission and scanning electron microscopy, histology and cytology, immunocytochemistry, enzyme immobilisation, cross-linked enzyme aggregates (CLEAs) and crystals, protein–protein conjugates, biosensors, chitosan, gelatin, collagen and albumin materials, hydrogels and microcapsules, polyvinyl alcohol and polyamine membranes, toxoid vaccine production, bioprosthetic tissue fixation, X-ray film hardening, leather tanning.

The dialdehyde is a saturated aliphatic dialdehyde. Pure Glutaraldehyde (1,5-Pentanedial) is a colourless, oily liquid with a sharp odour, but it is not stored in pure form because the aldehyde groups react with each other. Commercial Glutaraldehyde (1,5-Pentanedial) is an aqueous solution.
Industrially, Glutaraldehyde (1,5-Pentanedial) is made mainly from acrolein and a vinyl ether, which react in a hetero-Diels–Alder reaction to give a 2-alkoxy-3,4-dihydro-2H-pyran, acid hydrolysis of this ring opens it to Glutaraldehyde (1,5-Pentanedial) and the corresponding alcohol. Oxidation of cyclopentene with hydrogen peroxide over tungsten catalysts is an alternative route. Historically, Glutaraldehyde (1,5-Pentanedial) was first made in 1908 by oxidation of 1,5-pentanediol.

CAS NO, EC / EINECS NO AND CHEMICAL IDENTIFICATION OF GLUTARALDEHYDE (1,5-PENTANEDIAL)

Product name: Glutaraldehyde (1,5-Pentanedial)
IUPAC name: Pentanedial
CAS No: 111-30-8
EC / EINECS No: 203-856-5
EU Index No: 605-022-00-X
Molecular formula: C5H8O2
Molecular weight: 100.12 g/mol
Linear formula: OHC(CH2)3CHO
SMILES: O=CCCCC=O
InChI: InChI=1S/C5H8O2/c6-4-2-1-3-5-7/h4-5H,1-3H2
InChIKey: SXRSQZLOMIGNAQ-UHFFFAOYSA-N
PubChem CID: 3485
Chemical class: Aliphatic dialdehyde, homobifunctional crosslinker

AQUEOUS CHEMISTRY OF GLUTARALDEHYDE (1,5-PENTANEDIAL)

In water, Glutaraldehyde (1,5-Pentanedial) is present as a dynamic mixture:
Free dialdehyde: the open-chain form OHC(CH2)3CHO, which absorbs UV light at about 280 nm.
Hydrates: one or both aldehyde groups add water to form gem-diols.
Cyclic hemiacetal: the monohydrate cyclises to a six-membered 2,6-dihydroxytetrahydropyran ring, which is a major species in dilute solution.
Oligomers: on ageing, and much faster at alkaline pH, Glutaraldehyde (1,5-Pentanedial) undergoes aldol condensation and dehydration to alpha,beta-unsaturated oligomers, which absorb UV light at about 235 nm.

Purity index: for electron microscopy, the ratio of UV absorbance at 235 nm (polymer) to 280 nm (monomer) is used as a quality indicator. A low ratio means a low content of polymerised Glutaraldehyde (1,5-Pentanedial), EM-grade solutions are supplied with a low ratio, often in sealed ampoules under inert gas.
pH and stability: acidic solutions (about pH 3–5) of Glutaraldehyde (1,5-Pentanedial) are stable for long periods, neutral to alkaline solutions are more reactive and slowly polymerise and turn yellow. Fixatives and crosslinking solutions are therefore prepared fresh from an acidic stock and buffered just before use.

THE CROSSLINKING REACTION OF GLUTARALDEHYDE (1,5-PENTANEDIAL)

Target groups: the main target of Glutaraldehyde (1,5-Pentanedial) is the epsilon-amino group of lysine, N-terminal amino groups, and to a lesser extent thiol, phenol (tyrosine), imidazole (histidine) and hydroxyl groups, can also react.
Mechanism: an aldehyde group condenses with an amine to form a Schiff base (imine). Simple imines are reversible, but Glutaraldehyde (1,5-Pentanedial) systems also react through their alpha,beta-unsaturated oligomers by Michael addition and form conjugated, much more stable linkages, including pyridinium-type structures. This explains why crosslinks formed by Glutaraldehyde (1,5-Pentanedial) are remarkably stable to acid, heat and denaturing agents.
Reaction conditions: crosslinking is usually carried out at pH 7–8 in buffers without primary amines (for example phosphate, HEPES or cacodylate rather than Tris or glycine). Reaction time ranges from minutes to hours, depending on concentration and temperature.
Quenching and reduction: excess Glutaraldehyde (1,5-Pentanedial) can be quenched with glycine, Tris, lysine or ethanolamine. Imines can be reduced with sodium borohydride or sodium cyanoborohydride to stabilise the linkage and reduce autofluorescence.
Spacer length: the five-carbon chain gives a short spacer, but the oligomers in solution can bridge longer distances, so Glutaraldehyde (1,5-Pentanedial) does not behave as a crosslinker of one defined length.

PHYSICAL AND CHEMICAL PROPERTIES OF GLUTARALDEHYDE (1,5-PENTANEDIAL)

PURE COMPOUND:
Appearance: Colourless, oily liquid
Odour: Pungent, sharp
Molecular weight: 100.12 g/mol
Melting point: approx. -14 °C
Boiling point: approx. 187–189 °C (decomposes)
Density: approx. 1.06 g/cm³
Log Pow: approx. -0.36
Solubility: Miscible with water, soluble in ethanol, ether and many organic solvents

TYPICAL COMMERCIAL SOLUTIONS:
25 % solution: colourless liquid, density approx. 1.06 g/cm³, pH approx. 3, boiling point approx. 100–101 °C, melting point approx. -10 °C
50 % solution: colourless to pale yellow liquid, specific gravity approx. 1.12–1.13, pH approx. 3–5
EM grade (for example 8 % or 25 %): low polymer content, supplied in ampoules or under inert gas

Reactivity: reacts with amines, ammonia, hydrazines, proteins and alcohols (acetal formation), polymerises in alkaline solution, incompatible with strong acids, strong bases and strong oxidisers, air- and light-sensitive.

Grade-specific data (assay, A235/A280 ratio, acidity, methanol content) are available on request from Ataman Kimya.

LABORATORY AND MATERIAL SCIENCE APPLICATIONS OF GLUTARALDEHYDE (1,5-PENTANEDIAL)

Electron microscopy: primary fixation of tissue and cells with Glutaraldehyde (1,5-Pentanedial) (often 2–3 % in 0.1 M phosphate or cacodylate buffer, or mixed with formaldehyde as in Karnovsky-type fixatives), followed by osmium tetroxide post-fixation of lipids, dehydration and embedding.
Immunocytochemistry: low concentrations of Glutaraldehyde (1,5-Pentanedial) (for example around 0.1–0.5 % together with formaldehyde) improve morphology while preserving some antigenicity.
Enzyme immobilisation: Glutaraldehyde (1,5-Pentanedial) activates amine-carrying supports (aminopropyl silica, chitosan, aminated resins) or crosslinks enzymes adsorbed on carriers. A well-known industrial example is immobilised glucose isomerase for high fructose syrup production.
Cross-linked enzyme aggregates (CLEAs) and crystals: enzymes are precipitated and then crosslinked with Glutaraldehyde (1,5-Pentanedial) to form carrier-free, reusable biocatalysts.
Protein conjugates: two-step Glutaraldehyde (1,5-Pentanedial) methods are used to couple enzymes such as peroxidase or alkaline phosphatase to antibodies.
Biomaterials: Glutaraldehyde (1,5-Pentanedial) crosslinks collagen, gelatin, chitosan and albumin to make films, scaffolds, microspheres and hydrogels with lower swelling and higher strength. Glutaraldehyde-fixed porcine valves and bovine pericardium are used in bioprosthetic heart valves, residual aldehyde groups and calcification are known topics in this field.
Polymers: Glutaraldehyde (1,5-Pentanedial) crosslinks polyvinyl alcohol via acetal formation (with acid catalysis) and polyamines such as polyethyleneimine and polyallylamine, for membranes and coatings.
Vaccines: treatment of bacterial toxins with Glutaraldehyde (1,5-Pentanedial) produces toxoids, for example in some pertussis vaccine components.

OTHER USES OF GLUTARALDEHYDE (1,5-PENTANEDIAL)

Glutaraldehyde is also widely used as a high-level disinfectant and cold sterilant for medical devices, as an industrial biocide in oilfield, cooling and process water, as a tanning agent in leather manufacture, as a disinfectant for animal houses, in embalming fluids and as a gelatin hardener in photographic and X-ray materials.

WHICH PROBLEMS DOES GLUTARALDEHYDE (1,5-PENTANEDIAL) SOLVE?

- Cell and tissue structure collapses during preparation for microscopy → Glutaraldehyde (1,5-Pentanedial) fixes proteins quickly and preserves ultrastructure.
- Soluble enzymes cannot be reused or recovered → Glutaraldehyde (1,5-Pentanedial) immobilises them on carriers or as CLEAs.
- Gelatin or chitosan films dissolve or swell too much → Glutaraldehyde (1,5-Pentanedial) crosslinks them.
- Protein crystals are too fragile for soaking experiments → Glutaraldehyde (1,5-Pentanedial) vapour or solution crosslinking stabilises them.
- An enzyme–antibody conjugate is needed with a simple method → Glutaraldehyde (1,5-Pentanedial) coupling is fast and inexpensive.

THINGS TO CONSIDER WHEN WORKING WITH GLUTARALDEHYDE (1,5-PENTANEDIAL)

- Use the right grade: EM-grade Glutaraldehyde (1,5-Pentanedial) for microscopy, technical 25 % or 50 % solutions for general crosslinking and industrial use.
- Prepare working solutions fresh and buffer them just before use, avoid amine-containing buffers during crosslinking.
- Control concentration and time: too much Glutaraldehyde (1,5-Pentanedial) causes over-crosslinking, loss of enzyme activity or antigenicity, brittleness and autofluorescence.
- Quench and wash: remove or block residual aldehyde groups, especially for cell culture, implants or food-related enzymes.
- Store stocks cold, dark and tightly sealed, check ageing (yellowing, A235/A280 ratio).
- Always handle Glutaraldehyde (1,5-Pentanedial) in a fume hood, it is a strong irritant and a respiratory and skin sensitiser.

INITIAL FORMULATION APPROACHES WITH GLUTARALDEHYDE (1,5-PENTANEDIAL)

The percentage compositions below are illustrative laboratory starting points, not validated commercial recipes. Percentages refer to components as supplied and total 100.00 % by weight in each example. Final buffer concentration, pH, enzyme activity, fixation quality and residual aldehydes require laboratory validation by trained personnel.

1. KARNOVSKY-TYPE FIXATIVE FOR ELECTRON MICROSCOPY
Illustrative initial components (% w/w):
EM-grade glutaraldehyde solution (25 %): 10.00 %
Freshly prepared formaldehyde solution (16 %, from paraformaldehyde): 12.50 %
Phosphate buffer solution: 77.50 %
Total: 100.00 %
This composition provides 2.50 % active glutaraldehyde and 2.00 % active formaldehyde by weight. Prepare the buffer phase so that the final mixture meets 0.1 M phosphate and pH 7.2–7.4, confirm molarity using the actual final volume. This example selects phosphate rather than cacodylate buffer.

Combine EM-grade Glutaraldehyde (1,5-Pentanedial) to about 2–2.5 % and freshly prepared formaldehyde (from paraformaldehyde) to about 2 % in 0.1 M phosphate or cacodylate buffer, pH about 7.2–7.4. Fix small tissue blocks for 1–2 hours, rinse in buffer and post-fix with osmium tetroxide.

2. CROSS-LINKED ENZYME AGGREGATES (CLEAS)
Illustrative initial components (% w/w):
Precipitated enzyme suspension prepared for the selected system: 98.00 %
Glutaraldehyde solution (25 %): 2.00 %
Total: 100.00 %
This mixture contains 0.50 % active glutaraldehyde by weight. At an assumed mixture density of 1.00 kg/L, this corresponds to approximately 49.94 mM, calculate the actual molarity from the measured final volume. The suspension is a pre-established base, not a complete enzyme precipitation recipe, its protein content, precipitant and any co-protein must be defined and optimised separately.

Precipitate the enzyme with ammonium sulphate, a water-miscible solvent or a polymer, then add Glutaraldehyde (1,5-Pentanedial) to a final concentration in the range of about 10–100 mM and stir for a few hours at low temperature. Quench, wash and test activity and stability. Adding a lysine-rich protein (such as BSA) can improve crosslinking of enzymes with few lysines.

3. GLUTARALDEHYDE-ACTIVATED AMINO SUPPORT
Illustrative initial components for an activation suspension (% w/w):
Washed amine-functional carrier: 1.00 %
Phosphate buffer solution: 91.00 %
Glutaraldehyde solution (25 %): 8.00 %
Total: 100.00 %
The activation suspension contains 2.00 % active glutaraldehyde by total mass. Adjust the buffer phase so the suspension reaches approximately pH 7. This example covers activation only, the subsequent protein loading, washing, blocking and any reduction steps must be defined separately for the selected carrier and protein.

Wash an amine-functional carrier with phosphate buffer (pH about 7), treat it with about 1–2.5 % Glutaraldehyde (1,5-Pentanedial) for 1 hour, wash thoroughly to remove free aldehyde, then incubate with the protein solution. Block remaining aldehyde groups with glycine or ethanolamine and, if needed, reduce with sodium borohydride.

These are typical starting conditions from the literature and must be optimised for each system.

HOW DOES GLUTARALDEHYDE (1,5-PENTANEDIAL) WORK AT THE MOLECULAR LEVEL?
 
The systematic name 1,5-pentanedial already describes how the molecule works: a straight five-carbon chain with an aldehyde group at carbon 1 and another at carbon 5. Glutaraldehyde (1,5-Pentanedial) therefore behaves as a bifunctional crosslinker, able to react at both ends and tie together molecules that carry nucleophilic groups, especially amines.
 
Chain length and spacing: The three methylene groups between the two aldehyde ends give the molecule a short but flexible spacer. This distance allows the dialdehyde to bridge reactive groups that sit close to each other on one protein, on two adjacent proteins, or between a protein and a solid carrier. A shorter dialdehyde such as glyoxal bridges much smaller gaps, while monoaldehydes such as formaldehyde form only very short links; this difference is one reason pentanedial gives fast and strong crosslinking.
 
Dynamic chemistry in solution: Commercial solutions do not contain only the open-chain dialdehyde. Water adds to the carbonyl groups to form hydrates, the molecule can close into a six-membered cyclic hemiacetal, and over time small oligomers and α,β-unsaturated condensation products appear. Only part of this mixture carries free, reactive aldehyde at any moment, and the proportions shift with concentration, temperature, pH and storage time.
 
Main reaction pathways: Glutaraldehyde (1,5-Pentanedial) reacts most readily with primary amino groups, especially the ε-amino group of lysine. Addition to the carbonyl forms imines (Schiff bases), and these can be stabilised further when unsaturated oligomers undergo Michael-type addition with amines. Repeated reactions at both chain ends build a three-dimensional covalent network. Sulfhydryl, phenolic, imidazole and hydroxyl groups react to a smaller extent and can add further links.
 
Acid versus alkaline conditions: Under acidic conditions the aldehyde groups remain largely hydrated or cyclised, so the solution is stable but reacts slowly. Raising the pH to a mildly alkaline range releases more reactive species and increases reaction speed with amines; the trade-off is faster self-condensation of the dialdehyde, which gradually consumes active aldehyde and darkens the solution. This balance between reactivity and stability is the chemical basis for supplying acidic concentrates that are activated shortly before use.
 
Action on microorganisms: Microbial cells present large numbers of amino groups in their envelope proteins, peptidoglycan-associated structures and surface enzymes. 1,5-Pentanedial crosslinks these sites, sealing the cell surface, disrupting transport and inactivating enzymes involved in growth and division. Because many targets are hit at the same time, resistance through a single mutation is unlikely. Penetration is the limiting step for bacterial spores and some mycobacteria, which is why these organisms require longer exposure.
 
Action on structural proteins: In collagen, the same crosslinking increases the thermal and mechanical stability of fibres. This is why the dialdehyde is used in leather tanning, in fixing tissue samples for microscopy, and in stabilising biological materials such as bioprosthetic tissue. Crosslinks reduce swelling and protect the protein framework against enzymatic breakdown.
 
Industrial water and process systems: In cooling water, oilfield water and paper process water, glutaraldehyde (1,5-Pentanedial) reacts with proteins of bacteria in the water and in biofilms. Its activity is relatively tolerant of hardness salts, and it does not depend on oxidation, so it can be used where oxidising biocides would attack equipment or other process chemicals.
 
Consumption and deactivation: Any substance with free amino or sulfite groups competes for the aldehyde. High levels of organic matter, proteins or ammonia in a system therefore consume part of the active substance before it reaches microorganisms. The same principle is used for deliberate deactivation: sodium bisulfite, glycine or ammonium compounds are added to bind remaining aldehyde before discharge.
 
Interaction with living tissue: The amino groups that make the dialdehyde useful are also present in human skin and airway proteins. Covalent modification of these proteins explains the irritant effect and the potential for skin and respiratory sensitisation, so handling requires good ventilation and suitable protective equipment.
 
Crosslinking speed and biocidal effect depend on concentration, pH, temperature, contact time and the organic load of the system. Glutaraldehyde (1,5-Pentanedial) dosage and process conditions should therefore be confirmed through laboratory trials.

ALTERNATIVES TO GLUTARALDEHYDE (1,5-PENTANEDIAL)

Formaldehyde / paraformaldehyde: smaller, faster-penetrating, reversible fixative, less structural preservation.
Glyoxal: alternative aldehyde fixative with different reactivity.
Genipin: natural, less cytotoxic crosslinker for biomaterials.
Carbodiimides (EDC, with NHS): zero-length crosslinkers between carboxyl and amino groups.
NHS-ester crosslinkers (such as DSS, BS3): defined-length homobifunctional amine crosslinkers.
Heterobifunctional crosslinkers (such as SMCC, sulfo-SMCC): amine-to-thiol coupling with better control.
Transglutaminase and other enzymatic crosslinking.
Ortho-phthalaldehyde, peracetic acid and hydrogen peroxide: alternatives for disinfection.

QUALITY CONTROL AND PURCHASING CRITERIA FOR GLUTARALDEHYDE (1,5-PENTANEDIAL)

- concentration and assay method (GC, or titration of the oxime formed with hydroxylamine hydrochloride)
- grade (technical, laboratory, EM grade) and A235/A280 ratio for EM work
- appearance and colour (APHA), yellowing indicates polymerisation
- pH and acidity
- methanol and other impurities
- packaging (ampoules under inert gas, bottles, drums) and storage temperature
- documents: COA, SDS, TDS

Available grades, concentrations and specifications of Glutaraldehyde (1,5-Pentanedial) are available on request from Ataman Kimya.

STORAGE AND HANDLING OF GLUTARALDEHYDE (1,5-PENTANEDIAL)

Keep stock solutions of Glutaraldehyde (1,5-Pentanedial) tightly closed in the original container, protected from light and air, in a well-ventilated, locked storage area away from amines, alkalis and oxidisers. Laboratory and EM grades are typically stored refrigerated or frozen as stated by the supplier (some reagent grades at -20 °C), and opened ampoules should be used promptly. Handle only in a fume hood or with effective local exhaust, and avoid vapour and aerosol generation.

SAFETY OF GLUTARALDEHYDE (1,5-PENTANEDIAL)

Glutaral is classified in the EU (CLP Annex VI) as toxic if swallowed (H301), fatal if inhaled (H330), causing severe skin burns and eye damage (H314, H318), a respiratory sensitiser (H334), a skin sensitiser (H317), causing respiratory irritation (H335), very toxic to aquatic life and toxic with long lasting effects (H400, H411), and corrosive to the respiratory tract (EUH071). Diluted solutions are classified according to their concentration, for example, supplier SDS for a 25 % solution show the signal word Danger with H302 + H332, H314, H317, H334, H335, H410 and EUH071.
The most important risk in the laboratory is sensitisation: repeated exposure to Glutaraldehyde (1,5-Pentanedial) vapour can cause occupational asthma and skin contact can cause allergic dermatitis. Very low exposure limits apply, for example, the ACGIH ceiling value is 0.05 ppm.
Personal protection: work in a fume hood, tightly fitting goggles, face shield when handling concentrates, nitrile or butyl rubber gloves (latex is not suitable), laboratory coat or acid-resistant clothing, respiratory protection with a combination filter (for example ABEK) if exposure cannot be avoided.
First aid: move to fresh air and get medical help after inhalation, remove contaminated clothing and rinse skin with water, rinse eyes immediately with plenty of water and call an ophthalmologist, after swallowing, give water to drink (at most two glasses), do not induce vomiting and call a physician.
Waste: collect waste Glutaraldehyde (1,5-Pentanedial) or deactivate it (for example with glycine or sodium bisulphite) according to local regulations, do not pour concentrates into the drain.
Regulatory: glutaral has been on the REACH SVHC Candidate List since July 2021 because of its respiratory sensitising properties.
The SDS of the supplied grade is available on request from Ataman Kimya.

BUYING GLUTARALDEHYDE (1,5-PENTANEDIAL)

Pentanedial is available in laboratory packs (ampoules and bottles of EM-grade or reagent solutions) and in industrial packaging (drums and IBCs of 25 % or 50 % solutions). When requesting Glutaraldehyde (1,5-Pentanedial), please specify concentration, grade, pack size and application. Grades and pack sizes are available on request from Ataman Kimya.

SUPPLY OF GLUTARALDEHYDE (1,5-PENTANEDIAL) FROM ATAMAN KIMYA

Ataman Kimya supplies Glutaraldehyde (1,5-Pentanedial) solutions to industrial, research and formulation customers. Ataman Kimya provides SDS, TDS and COA documents and supports customers with grade selection, packaging and safe transport. For quotations, please contact Ataman Kimya.

FREQUENTLY ASKED QUESTIONS ABOUT GLUTARALDEHYDE (1,5-PENTANEDIAL)

IS 1,5-PENTANEDIAL THE SAME AS GLUTARALDEHYDE?
Yes. 1,5-Pentanedial is the systematic name of glutaraldehyde, CAS 111-30-8.

WHY DOES MY GLUTARALDEHYDE (1,5-PENTANEDIAL) SOLUTION TURN YELLOW?
Yellowing indicates polymerisation (aldol condensation), which is faster at neutral or alkaline pH, at higher temperature and with age.

WHAT IS EM-GRADE GLUTARALDEHYDE (1,5-PENTANEDIAL)?
A purified solution with a low content of polymerised glutaraldehyde, checked by the A235/A280 UV ratio and usually supplied in sealed ampoules.

WHICH BUFFER SHOULD BE USED FOR CROSSLINKING WITH GLUTARALDEHYDE (1,5-PENTANEDIAL)?
An amine-free buffer such as phosphate, HEPES or cacodylate, Tris and glycine react with glutaraldehyde.

ARE GLUTARALDEHYDE CROSSLINKS REVERSIBLE?
Largely not. Unlike formaldehyde crosslinks, most glutaraldehyde crosslinks are very stable and are not reversed by heating.

HOW CAN EXCESS GLUTARALDEHYDE (1,5-PENTANEDIAL) BE REMOVED AFTER CROSSLINKING?
By washing and by quenching with glycine, Tris, lysine or ethanolamine, reduction with sodium borohydride also reduces aldehyde-induced autofluorescence.

WHY IS GLUTARALDEHYDE (1,5-PENTANEDIAL) USED TOGETHER WITH FORMALDEHYDE IN FIXATIVES?
Formaldehyde penetrates faster and fixes provisionally, while Glutaraldehyde (1,5-Pentanedial) follows and forms stronger, more stable crosslinks.

GLUTARALDEHYDE (1,5-PENTANEDIAL) – TECHNICAL SUMMARY

Product name: Glutaraldehyde (1,5-Pentanedial)
Other names: Glutaraldehyde, Pentanedial, Glutaral, Glutaric dialdehyde
CAS No: 111-30-8
EC No: 203-856-5
Molecular formula: C5H8O2
Molecular weight: 100.12 g/mol
Structure: OHC-(CH2)3-CHO
Supply forms: Aqueous solutions (for example 8 %, 25 %, 50 %, EM grade)
Pure compound: mp approx. -14 °C, bp approx. 187–189 °C (dec.)
Reactive towards: Primary amines (lysine), thiols, hydroxyl groups
Key quality parameter for EM: Low A235/A280 ratio (low polymer content)
Main uses: Protein crosslinking, EM fixation, enzyme immobilisation, biomaterials, disinfection, biocide, tanning
Hazards: H301, H330, H314, H318, H334, H317, H335, H400, H411, EUH071 (substance)
Storage: Tightly closed, cool, dark, under inert gas for sensitive grades

Glutaraldehyde (1,5-Pentanedial) can be sourced from ATAMAN KİMYA. For further information and supply inquiries about Glutaraldehyde (1,5-Pentanedial), please contact ATAMAN KİMYA.