Hello Jérôme,

Answering your question, yes you can design an affinity chromatography column with the ligand or drug of your choice. Many companies that develop chromatography columns have specialists that can custom design your chromatography resin using an appropriate base matrix for your selected ligand in case the column you require is not part of their standard product offering.

Among the companies that offer this service, there is Cytiva, which was formerly known as GE Healthcare Life Sciences. The company has already been successful in developing affinity chromatography resins that have high selectivity for the efficient industrial purification of Factor VII, VII, and adeno-associated viruses for example. Here I provide you the link where you can find additional information regarding their services and contact them if you wish to do so.

https://www.cytivalifesciences.com/en/us/business-partnerships/custom-design-solutions/custom-chromatography-media

Another company that can design custom affinity ligands and custom resins to solve your purification challenges is ThermoFisher Scientific, which has already created affinity resins that can be used to efficiently purify different pharmaceuticals, cells, and viruses. I provide the link where you can find further details regarding this option.

https://www.thermofisher.com/mx/es/home/life-science/bioproduction/poros-chromatography-resin/custom-chromatography-services/custom-ligand-development.html

Finally, I provide two additional options from other companies whose scientists can help you in the design of the column you need.

https://marvelgent.com/pages/custom-chromatography-service

http://www.landrauscientific.com/custom-chromatography

I suggest you contact them to verify if your required column has not already been developed using any of the ligands you mention because the time for the development of these columns is usually long and the price is higher when compared with pre-build columns.

Dear Jeromé,

There are no beads of matrix commercially available with a drug as a ligand; however some trading houses sell the materials needed to make your resin for the affinity chromatography. It is possible to buy the pre-activated base matrix (usually polymeric carriers) and chemically attach your interest's ligand. However, it is crucial to determine the chemical reaction to attach your ligand to the spacers or directly to the matrix.

Marvin Sketch by Chem Axon A is a software useful for designing the reaction pathway for the adsorbent's chemical synthesis of your interest. This software can help you predict the pKa value and characterize the reactions, chemical structures, and substructures.

Most of the ligands used for affinity chromatography are immobilized (coupled) to a polymeric base matrix by covalent bonds. They use amines, sulfhydryl, hydroxyl or carbonyl groups on the ligand to make the covalent bond with the matrix. So, make sure if the drug you need to use as a ligand has functional groups to make the attachment and see the type of activation of the matrix (see article [1] to know immobilization methods and the reactions involved). Azytromycin and Fosfomycin have some hydroxyl groups that can be used to make the attachment; however, another essential aspect to consider is the loss or interference of activity due to the attachment site or if the drug is stable to the condition of the reaction attachment.

If the drug does not allow a covalent attachment to the matrix, it is possible to use non-covalent immobilization for affinity ligands based on physical adsorption. These methods use electrostatic interactions, hydrogen bonding or hydrophobic interactions, and secondary ligands. It may be interesting to you. Encapsulation can be made by forming an organic polymer around the affinity ligand, using silicate-based sol-gels, placing the ligand on or within cross-linked support. However, non-covalent immobilization presents some disadvantages; for example, the ligand has limited stability for the support and loss of the binding activity because of random orientation (see article [2] to know used non-covalent immobilization strategies for affinity chromatography). The mentioned non-covalent immobilization method has been proved with proteins or enzymes as a ligand; however, it would be interesting the development of these techniques of another type of ligands. Furthermore, the interaction between the material must be analyzed to avoid the loss of the drug activity.

Alternatively, there are several examples of studies in which drugs such as the ones you mentioned are immobilized in order to study their interaction with proteins of interest, or for the development of a drug delivery system. One of the antibiotics you mentioned, Azithromycin, is used to treat eye infections caused by bacteria. Due to the low solubility of this drug, it is necessary to encapsulate it in an ocular delivery system. Liposomes are microspheres composed of a lipid bilayer that could increase the permeability of this drug through the human body. One of its advantages is that the chemical reaction involved in the drug immobilization does not interfere with the biological activities of the ligand. Ion pairing is a novel strategy used to increase the lipophilicity of drugs; the drug of interest is attached by a hydrogen bond to a lipophilic molecule. This newly formed complex can now interact with a liposome and provide a stable platform. (See articles [3] for more information)

Perhaps an immobilized artificial membrane (IAM) chromatography may be of interest to you. These types of columns are designed to emulate the conditions of a cell membrane, and they are often used to analyze drug-protein interactions; with the previous example of azithromycin encapsulation in mind, you can theoretically make a column with such characteristics. Their stationary phase consists of phospholipids covalently bound to a propylamino-silica skeleton. (The article [4] reviews the current state of the IAM columns).

For more information regarding liposomes as encapsulating agents, you can check the article [5]. Finally, this is another article about immobilized artificial membranes [6].

Hopefully this answer gave you some insight into the world of affinity chromatography as a tool for drug-protein interaction studies or any other application you need.

References.

[1] Bahadir, O., Saltan, G., Ozbilgin, S., & Ergene, B. (2013). Affinity Chromatography and Importance in Drug Discovery. Column Chromatography. doi:10.5772/55781

[2] Rodriguez, E. L., Poddar, S., Iftekhar, S., Suh, K., Woolfork, A. G., Ovbude, S., … Hage, D. S. (2020). Affinity Chromatography: A Review of Trends and Developments over the Past 50 Years. Journal of Chromatography B, 122332. doi:10.1016/j.jchromb.2020.122332

[3] Ren, T., Lin, X., Zhang, Q., You, D., Liu, X., Tao, X., ... & Tang, X. (2018). Encapsulation of azithromycin ion pair in liposome for enhancing ocular delivery and therapeutic efficacy on dry eye. Molecular pharmaceutics, 15(11), 4862-4871.

[4] Tsopelas, F., Vallianatou, T., & Tsantili-Kakoulidou, A. (2016). Advances in immobilized artificial membrane (IAM) chromatography for novel drug discovery. Expert Opinion on Drug Discovery, 11(5), 473–488. doi:10.1517/17460441.2016.1160886

[5] Alavi, M., Karimi, N., & Safaei, M. (2017). Application of various types of liposomes in drug delivery systems. Advanced pharmaceutical bulletin, 7(1), 3.

[6] Tsantili-Kakoulidou, A. (2020). How can we better realize the potential of immobilized artificial membrane chromatography in drug discovery and development?.

Good Day,

I may be a little bit late, but I hope that I can still be of help here.

You have in priciple two options here:

1. Bind your drug/ligand by yourself to agarose beads or magentic beads. Depending on the drug / ligand this of course needs sometimes different chemical bonds. For this reason Cube Biotech offers 5 different activated bead types fro this purpose (NHS, Amine, Carboxy, Epoxy, Maleimide). You can find out here here:

https://cube-biotech.com/products/protein-purification-products/activated-resins-magbeads/

2. The second option would be the direct request of custom beads from a supplier that offers this service. Of course I saw that Thermo and Cytiva have been mentioned before of course. But in our experience they tend to be a little bit expensive. Maybe we can help you out.

https://cube-biotech.com/customized-resins-maximum-specificity

Hope this (still) helps. Feel free to PM me if you have any questions.