Editorial Feature

What is a Carbohydrate Polymer?

Carbohydrate polymers are chains of carbohydrate molecules bound together in repeating units, hence the polymer denotation.

Image Credit: Magcom/Shutterstock.com

Carbohydrate Polymers: An Introduction

Carbohydrate polymers possess the general chemical formula Cn(H2O)m, in that there are generally two hydrogen atoms for every oxygen atom, though the ratio between n and m may vary, and not all molecules with this formula are necessarily carbohydrate polymers.

Carbohydrates are synonymous with saccharides, which include low molecular weight mono- and di-saccharides, often termed sugars, and polysaccharides such as starch and cellulose, which may often be constructed from the same repeating monosaccharides.

The chemical and bulk physical properties of carbohydrate polymers may also be exploited in the clinic in the production of biocompatible materials for wound dressings and drug delivery agents.

History of Carbohydrate Polymers

The diagnosis of insulin resistance or diabetes has reportedly been performed as early as the sixth century BCE. An Indian physician identified overly-sweet urine and prescribed exercise and a diet reduced in carbohydrate polymers such as rice.

Thomas Willis first identified this in scientific literature in the 17th century, and by the 19th, a white powder indistinguishable from sugar obtained from grapes, honey, or starch was isolated from the urine of people with diabetes.

This substance was termed glucose, after the Greek gleukos, meaning sweet wine, while another substance originating from plant cell walls was named cellulose.

Later, common sugar originating from sugarcane or beet was named sucrose, and these compounds were recognized as distinct.

Glycogen was named based on its ability to convert to glucose in the liver, and recognized as a carbohydrate polymer constructed of glucose monomers. The common Cn(H2O)m general formula between these molecules was established in the later half of the 19th century, and the term carbohydrate was coined from the French hydrate de carbone.

Around this time, Professor Emil Fishcher published extensively on the configuration of carbohydrates and carbohydrate polymers and performed the synthesis of numerous novel sugars, laying the groundwork for chemical nomenclature; i.e. pentose, hexose.

The chemical makeup of common carbohydrate polymers such as amylose, amylopectin (starch), glycogen, and cellulose was also unraveled around this time, allowing synthetic production in the lab.

How is a Carbohydrate Polymer Made?

Carbohydrate polymers are typically constructed from sugar monomers by condensation reactions, whether within the cells of living animals, the lab, or via the wide range of synthetic routes now available.

For example, glycogenesis is the process of producing the carbohydrate polymer glycogen from glucose monomers, which in animals largely takes place within the liver in response to insulin. Firstly, glucose undergoes phosphorylation by glucokinase or other enzymes, depending on cell type and location, facilitated by ATP.

Two phosphorylated glucose molecules are then joined together to form uridine diphosphate glucose (UDP-glucose) by another enzyme, UDP-glucose pyrophosphorylase. An enzyme termed glycogenin is then responsible for acting as a primer and initiating polymerization, achieved by catalyzing its bonding with UDP-glucose, and then that of the terminal monomer with additional glucose monomers. Other enzymes are involved in the further addition of UDP-glucose beyond around seven monomers and when introducing branches to the growing carbohydrate polymer. 

Noticeably, a number of enzymes are required for glycogenesis to overcome otherwise energetically unfavorable chemical transformations. Carbohydrate polymers such as glycogen can be produced from glucose monomers using catalysts and a complex set of chemical steps, though this is costly compared to utilizing enzymes.

A complex range of non-naturally occurring carbohydrate polymers can be produced by methods of organic synthesis, many of which pose intriguing potential applications.

Common Applications of Carbohydrate Polymers

Carbohydrate polymers have found applications in a wide variety of fields, particularly biochemistry and medicine, where they can be formed into biocompatible micro- and nanoparticles, or act as coating agents for particles constructed from less biocompatible materials.

One of the most widely utilized, naturally sourced, carbohydrate polymers is chitosan. Chitosan is a linear polysaccharide made from chitin, a glucose polymer found in the cell wall of fungi and the exoskeletons of arthropods. It is used in agriculture as an antifungal and antibacterial agent and has uses in industrial filtration and bioprinting. Interestingly, owing to the antibacterial properties of chitosan, the carbohydrate polymer has been explored as a biocompatible and biodegradable wound dressing agent.

Given that carbohydrate polymers, naturally occurring ones at least, are frequently exploited as food sources for a variety of micro- and macro-organisms, they are frequently subject to degradation by enzymes and other forms of biofouling.

Many naturally occurring carbohydrate polymers, such as chitosan, have therefore developed antimicrobial and antioxidant properties that can be exploited clinically.

A huge variety of synthetic carbohydrate polymers are therefore in development that aim to exploit and magnify these properties by mixing with other carbohydrate polymers and additives, generating polymers with highly specific functionality. For example, maximum water barrier effectiveness combined with antioxidant properties can be engineered by selecting appropriate carbohydrate polymers and mixing them together in proper proportion to produce a carbohydrate polymer composite.

Applying Carbohydrate Polymers to Nanotechnology 

Given the innate biocompatibility of natural carbohydrate polymers, they are frequently explored as bionanomaterial coatings or nanoparticle delivery systems. Chitosan is widely exploited as a lightweight and biodegradable drug delivery agent, able to be produced in a range of sizes, from tens to hundreds of nm, with a range of chemical modifications that enhance in vitro localization.

Glycans are carbohydrate polymers (polysaccharides) that provide protective and organizational functions to cells, and in combination with amino acids, form glycoproteins, which act as cell-surface receptors.

Glycans and glycoproteins have been explored as targets and targeting agents in nanomedicine for the localization of nanoparticles to sites of interest using complementary ligands known as lectins.

For example, Fard et al. (2022) found differing uptake of 120 nm nanodiamonds by three types of human brain cells dependent on lectin coating, with implications towards targeted diagnostic and therapeutic applications. 

The Applications of Carbohydrate Polymers

References and Further Reading

Bhattacharya, M. (2015). A historical exploration of Indian diets and a possible link to insulin resistance syndrome. Appetite, 95, pp. 421-454. https://pubmed.ncbi.nlm.nih.gov/26206172/

Bhattacharya, M. (2018). A history of evolution of the terms of carbohydrates coining the term ‘glucogenic carbohydrates’ and prescribing in grams per day for better nutrition communication. Journal of Public Health and Nutrition, 1(4).

Bloise, N., Okkeh, M., Restivo, E., Della Pina, C., & Visai, L.. (2021). Targeting the “Sweet Side” of Tumor with Glycan-Binding Molecules Conjugated-Nanoparticles: Implications in Cancer Therapy and Diagnosis. Nanomaterials11(2), p. 289. https://www.mdpi.com/2079-4991/11/2/289

Ghanimi Fard, M., Khabir, Z., Reineck, P., Cordina, N. M., Abe, H., Ohshima, T., Dalal, S., Gibson, B. C., Packer, N. H., & Parker, L. M.. (2022). Targeting cell surface glycans with lectin-coated fluorescent nanodiamonds. Nanoscale Advances4(6), pp. 1551–1564. https://pubs.rsc.org/en/content/articlelanding/2022/NA/D2NA00036A

Mohammed, M., Syeda, J., Wasan, K., & Wasan, E.. (2017). An Overview of Chitosan Nanoparticles and Its Application in Non-Parenteral Drug Delivery. Pharmaceutics9(4), p. 53. https://www.mdpi.com/1999-4923/9/4/53

Disclaimer: The views expressed here are those of the author expressed in their private capacity and do not necessarily represent the views of AZoM.com Limited T/A AZoNetwork the owner and operator of this website. This disclaimer forms part of the Terms and conditions of use of this website.

Michael Greenwood

Written by

Michael Greenwood

Michael graduated from the University of Salford with a Ph.D. in Biochemistry in 2023, and has keen research interests towards nanotechnology and its application to biological systems. Michael has written on a wide range of science communication and news topics within the life sciences and related fields since 2019, and engages extensively with current developments in journal publications.  

Citations

Please use one of the following formats to cite this article in your essay, paper or report:

  • APA

    Greenwood, Michael. (2023, July 19). What is a Carbohydrate Polymer?. AZoNano. Retrieved on May 28, 2024 from https://www.azonano.com/article.aspx?ArticleID=6487.

  • MLA

    Greenwood, Michael. "What is a Carbohydrate Polymer?". AZoNano. 28 May 2024. <https://www.azonano.com/article.aspx?ArticleID=6487>.

  • Chicago

    Greenwood, Michael. "What is a Carbohydrate Polymer?". AZoNano. https://www.azonano.com/article.aspx?ArticleID=6487. (accessed May 28, 2024).

  • Harvard

    Greenwood, Michael. 2023. What is a Carbohydrate Polymer?. AZoNano, viewed 28 May 2024, https://www.azonano.com/article.aspx?ArticleID=6487.

Tell Us What You Think

Do you have a review, update or anything you would like to add to this article?

Leave your feedback
Your comment type
Submit

While we only use edited and approved content for Azthena answers, it may on occasions provide incorrect responses. Please confirm any data provided with the related suppliers or authors. We do not provide medical advice, if you search for medical information you must always consult a medical professional before acting on any information provided.

Your questions, but not your email details will be shared with OpenAI and retained for 30 days in accordance with their privacy principles.

Please do not ask questions that use sensitive or confidential information.

Read the full Terms & Conditions.