In a paper published in the journal Biomacromolecules, a flexible and effective two-step method centered on triazine and azide-alkyne click-chemistry was devised for fluorescent labeling of nanoscale cellulose for use in microscopy applications.
The Vast Potential of Cellulose Nanomaterials
Cellulose, a major constituent of the cell wall in plants, is the most abundantly available structured biopolymer on the planet and is used extensively in the architecture, fabric, and paper industry. Crystalline cellulose nanoparticles generated from biomass, such as cellulose nanocrystals (CNCs) and cellulose nanofibrils (CNFs), have excellent thermal stability, tensile strength, and specific area.
Due to their unique features, sustainable nanoscale celluloses are already being employed in fields such as tissue engineering, nanomedicine, biosensors, biodegradable polymers, power storage, and water treatment.
Visualizing Nanocellulose Networks via Fluorescence Microscopy
The visualization of nanocellulose dispersion and dynamics within complicated frameworks is often required to use nanocelluloses in real world settings. If the nanocelluloses are luminous, fluorescent microscopy procedures may be used to visualize nanofibers and nanoparticles inside three-dimensional networks due to their sensitivity and selectivity.
According to a previous study, whenever fluorescent CNCs are utilized as medicine carriers, their absorption by macrophages and embryo cells can be tracked, and their biological distribution throughout tissues may be observed. The confocal microscopic technique has been used to study the dispersion of CNCs and their engagement with other elements in emerging bio-composites such as structural CNC polymeric hydrogels and CNC-protein-polymer frameworks.
Fluorescent cellulose has also been utilized to investigate the effects of pretreatment on the morphology, availability, and enzyme-triggered depolymerization of cellulose at high resolutions, hence helping to formulate effective biomass converting techniques.
However, modern scanning techniques such as multiphoton, light-sheet, and super-resolution imaging are seldom used in cellulose research. This is attributable, in part, to a lack of easy, quick, and inexpensive ways for fluorescent labeling of nanocelluloses without affecting their distinctive features.
Challenges Associated with Fluorescence Imaging of Nanocellulose
The difficulty of identifying cellulose in its original state stems from its chemically inert and insoluble nature. Cellulose is composed of linear β−1→4 anhydroglucose polymer (glucan) groups that form into densely packaged crystalline fibrils, showing insolubility in water due to an extensive hydrogen-bonding web.
According to documented fluorescent labeling techniques, the moderately responsive hydroxyl groups on the surface of cellulose are often derivatized with maleimide, amine, or N-hydroxysuccinimide groups which are responsive with supplementary moieties on commercially accessible pigments, and the tagging is carried out as a non-homogenous response.
Since most of these approaches rely on natural solvent swaps, which may promote nanocellulose agglomeration, triazinyl- and hydrazine-substituted fluorophores have been employed to generate aqueous single-step tagging procedures. Dichlorotriazinyl amino-fluorescein (DTAF), a widely accessible fluorophore that has been utilized to tag CNCs, CNFs, and bacterial cellulose (BC), is the most commonly employed pigment in these processes.
This labeling method is inefficient since it competes for hydrolysis processes in aqueous conditions, requiring a considerable surplus of DTAF to obtain significant labeling concentrations. The poor labeling effectiveness of DTAF, combined with its inadequate photostability, has also hampered its usage in high-resolution fluorescent microscopy.
Highlights of the Study
In this study, the researchers developed effective labeling techniques based on triazine linkers, allowing them to perform high-resolution fluorescent imaging on a range of nanocellulose materials. Initially, the fabrication of a novel triazine-based pigment, dichlorotriaznyl piperazine rhodamine (DTPR) was described, allowing cellulose to be labeled with a high-performing fluorophore in a single step.
A two-step triazine- and click-chemistry process was then used to label nanocellulose, avoiding complicated fabrication and lowering tagging costs. The second phase, specifically, required an effective click-reaction which could be done with any commonly obtainable pigment having azide activity. This enabled the employment of a diverse set of fluorophores in cellulose research.
Thanks to the capability of labeling cellulosic materials to varying extents while maintaining the original features of nanocellulose, this approach may be used to tag cellulose for a variety of fluorescence-based investigations and scanning purposes.
The versatility provided by triazine chemistry may also be employed to build bifunctional linkers that enable pigment labeling of nanocellulose for visualizing needs while also introducing a second activity that may be utilized for binding, cross-linkage, or sensing.
The approaches presented should give labeling avenues for visualizing cellulose nanoparticles, which are employed in a wide array of applications.

News
Unlocking hidden soil microbes for new antibiotics
Most bacteria cannot be cultured in the lab-and that's been bad news for medicine. Many of our frontline antibiotics originated from microbes, yet as antibiotic resistance spreads and drug pipelines run dry, the soil [...]
By working together, cells can extend their senses beyond their direct environment
The story of the princess and the pea evokes an image of a highly sensitive young royal woman so refined, she can sense a pea under a stack of mattresses. When it comes to [...]
Overworked Brain Cells May Hold the Key to Parkinson’s
Scientists at Gladstone Institutes uncovered a surprising reason why dopamine-producing neurons, crucial for smooth body movements, die in Parkinson’s disease. In mice, when these neurons were kept overactive for weeks, they began to falter, [...]
Old tires find new life: Rubber particles strengthen superhydrophobic coatings against corrosion
Development of highly robust superhydrophobic anti-corrosion coating using recycled tire rubber particles. Superhydrophobic materials offer a strategy for developing marine anti-corrosion materials due to their low solid-liquid contact area and low surface energy. However, [...]
This implant could soon allow you to read minds
Mind reading: Long a science fiction fantasy, today an increasingly concrete scientific goal. Researchers at Stanford University have succeeded in decoding internal language in real time thanks to a brain implant and artificial intelligence. [...]
A New Weapon Against Cancer: Cold Plasma Destroys Hidden Tumor Cells
Cold plasma penetrates deep into tumors and attacks cancer cells. Short-lived molecules were identified as key drivers. Scientists at the Leibniz Institute for Plasma Science and Technology (INP), working with colleagues from Greifswald University Hospital and [...]
This Common Sleep Aid May Also Protect Your Brain From Alzheimer’s
Lemborexant and similar sleep medications show potential for treating tau-related disorders, including Alzheimer’s disease. New research from Washington University School of Medicine in St. Louis shows that a commonly used sleep medication can restore normal sleep patterns and [...]
Sugar-Coated Nanoparticles Boost Cancer Drug Efficacy
A team of researchers at the University of Mississippi has discovered that coating cancer treatment carrying nanoparticles in a sugar-like material increases their treatment efficacy. They reported their findings in Advanced Healthcare Materials. Over a tenth of breast [...]
Nanoparticle-Based Vaccine Shows Promise in Fighting Cancer
In a study published in OncoImmunology, researchers from the German Cancer Research Center and Heidelberg University have created a therapeutic vaccine that mobilizes the immune system to target cancer cells. The researchers demonstrated that virus peptides combined [...]
Quantitative imaging method reveals how cells rapidly sort and transport lipids
Lipids are difficult to detect with light microscopy. Using a new chemical labeling strategy, a Dresden-based team led by André Nadler at the Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG) and [...]
Ancient DNA reveals cause of world’s first recorded pandemic
Scientists have confirmed that the Justinian Plague, the world’s first recorded pandemic, was caused by Yersinia pestis, the same bacterium behind the Black Death. Dating back some 1,500 years and long described in historical texts but [...]
“AI Is Not Intelligent at All” – Expert Warns of Worldwide Threat to Human Dignity
Opaque AI systems risk undermining human rights and dignity. Global cooperation is needed to ensure protection. The rise of artificial intelligence (AI) has changed how people interact, but it also poses a global risk to human [...]
Nanomotors: Where Are They Now?
First introduced in 2004, nanomotors have steadily advanced from a scientific curiosity to a practical technology with wide-ranging applications. This article explores the key developments, recent innovations, and major uses of nanomotors today. A [...]
Study Finds 95% of Tested Beers Contain Toxic “Forever Chemicals”
Researchers found PFAS in 95% of tested beers, with the highest levels linked to contaminated local water sources. Per- and polyfluoroalkyl substances (PFAS), better known as forever chemicals, are gaining notoriety for their ability [...]
Long COVID Symptoms Are Closer To A Stroke Or Parkinson’s Disease Than Fatigue
When most people get sick with COVID-19 today, they think of it as a brief illness, similar to a cold. However, for a large number of people, the illness doesn't end there. The World [...]
The world’s first AI Hospital, developed in China is transforming healthcare
Artificial Intelligence and its developments have had a revolutionary impact on society, and healthcare is not an exception. China has made massive strides in AI integrated healthcare, and continues to do so as AI [...]