PEG

306Oi9-cis2 is a multi-ionizable aminolipid analog of 306Oi10 which features a central amine linked to two identical amine-branched side chains. Each side chain is linked to unsaturated hydrophobic tails via biodegradable ester bonds. Ionizable lipids are typically used in the design of nucleic acid lipid nanoparticles, as their pH-dependent positive charge stabilizes the anionic nucleic acids they encapsulate.

N-(Azide-PEG8-carbonyl)-N-bis(PEG8-acid) is a trifunctional linker combining two carboxylic acids and a terminal azide group. The azide is reactive towards terminal alkynes, BCN or DBCO groups using click chemistry, while the carboxylic acids are free to react with primary amines to form stable amide bonds. This is highly water-soluble PEG linker with altered ADME properties.

N-(Propargyl-PEG4)-PEG4-N-Boc is a bifunctional linker containing a terminal alkyne and a Boc-protected amine. The terminal alkyne is reactive towards azides using copper click chemistry while the NH-Boc group can be deprotected to allow for reactions with carboxylic acids and other carbonyl groups like aldehydes or ketones.

N-(Mal-PEG8-carbonyl)-N-bis(PEG8-t-butyl ester) is a trifunctional PEG linker containing two t-butyl esters and a maleimide joined together at a tertiary amide. Maleimide is a thiol-specific covalent ligand, often used for labeling cysteine residues along proteins. The two t-butyl esters can be deprotected to allow for reaction with amines or alcohols to form amides and esters respectively. The tertiary amide increases aqueous solubility through hydrogen bonding effects.

TFA Amine-PEG-Fluor-647 TEA salts, MW 2,000 is a PEG-dye conjugate featuring a primary amine and a Fluor 647 dye. Primary amines are versatile building blocks which are most easily employed in coupling reactions with carboxylic acids with the help of activators such as HATU or EDC. Fluor 647 is a bright far-red fluorophore with excitation and emission maxima of 650 nm and 671 nm respectively.

N-(Mal-PEG4-carbonyl)-N-bis(PEG4-NHS ester) is a trifunctional linker that combines maleimide with two activated NHS esters. NHS esters are highly activated towards reactions with amines and alcohols to form amides and esters respectively, while Maleimide is a thiol-specific covalent ligand that is capable of easily labeling proteins such as antibodies. The central junction of this molecule is an amide, allowing for hydrogen bonding to increase the water solubility of this compound.

Ald-Ph-PEG8-acid is a PEG linker containing a benzaldehyde and a carboxylic acid. The aldehyde group is a versatile electrophile that is reactive towards amines, hydroxylamines, and hydrazines while the carboxylic acid may easily react with amines or alcohols in the presence of coupling reagents.

t-butyoxycarboxy-PEG4-para-Nitrophenyl carbonate is a PEG linker with a nitrophenyl group linked to a carbonate, four PEG units, and a t-butyl group that can be deprotected under acidic conditions. The PEG units enhance the solubility of the molecule in aqueous media. Nitrophenyl group is reactive towards the amino-bearing molecules.

PEG4-Bis-nitrophenyl carbonate is a water soluble PEG linker with two nitrophenyl carbonate groups that can react rapidly with primary amines.