Functional group polarity-modulated formation of liquid crystals of amphiphilic cyclodextrins

Today's cyclodextrin, ,

Today’s cyclodextrin:
At CarboHyde, we also deal with amphiphilic CDs; this application from this Canadian collaboration caught my attention.
Pseudo-face-to-face symmetry in the native CDs represents a distinctive advantage to designing amphiphilic materials capable of self-assembly into liquid crystals. In this work, a new family of amphiphilic β-CD derivatives possessing 14 stearoyl chains (non-polar) and 7 functionalized tetraethylene glycols were synthesized using an improved design and more efficient chemistry, and the synthetic targets showed excellent ability to form stable hexagonal columnar mesophases. Studies of a lithium composite revealed fast local Li-ion exchange processes with very low activation energies, suggesting the benefit of using these materials as potential electrolytes for high ionic conductions. The results from this work can guide the design of future generations of CD-based LC materials for ion conduction.

University of Calgary – Austin Che, Simon Trudel-Lachance, Jayar Espejo, Chang-Chun Ling
University of Alberta – Diganta Sarkar, Vladimir Michaelis
Simon Fraser University – Carson Zellman, Vance Williams

See the full article here: Functional group polarity-modulated formation of liquid crystals of amphiphilic cyclodextrins

Surface Modification of Bi2O3 Nanoparticles with Biotinylated β-Cyclodextrin as a Biocompatible Therapeutic Agent for Anticancer and Antimicrobial Applications

Egyéb kategória

Just because we think functionalizing cyclodextrin with biotin is fancy and could have a great variety of uses.
This paper describes a new route to the surface modification of bismuth oxide nanoparticles (Bi2O3 NPs) using functionalized beta-Cyclodextrin (β-CD) as a biocompatible system. The synthesis of Bi2O3 NP was done using PVA (polyvinyl alcohol) as the reductant and the Steglich esterification procedure for the functionalization of β-CD with biotin. Ultimately, the Bi2O3 NPs are modified using this functionalized β-CD system. The antibacterial and anticancer effects of the surface-modified Bi2O3 NP system were also investigated.
Jogy Alex and Thomas Mathew

See the full article here: Surface Modification of Bi2O3 Nanoparticles with Biotinylated β-Cyclodextrin as a Biocompatible Therapeutic Agent for Anticancer and Antimicrobial Applications

Effect of Substitution Degree and Homogeneity on Cyclodextrin-Ligand Complex Stability: Comparison of Fenbufen and Fenoprofen Using CD and NMR Spectroscopy

Today's cyclodextrin,

today’s cyclodextrin:
is a rarely applied analytical technique for the analysis of CD-complexes: circular dichroism, presented by the group at Semmelweis University where I got my PhD, so close to my heart.
The stability of host–guest complexes of two NSAID drugs with similar physicochemical properties, fenbufen and fenoprofen, was investigated by comparing induced circular dichroism and 1H nuclear magnetic resonance methods using eight cyclodextrins of different degrees of substitution and isomeric purity as guest compounds. These cyclodextrins include native β-cyclodextrin (BCyD), 2,6-dimethyl-β-cyclodextrin 50 (DIMEB50), 80 (DIMEB80) and 95% (DIMEB95) isomerically pure versions, low-methylated CRYSMEB, randomly methylated β-cyclodextrin (RAMEB) and 4.5 and 6.3 average substitution grade hydroxypropyl-β-cyclodextrin (HPBCyD). The stability constants obtained by the two methods show good agreement in most cases. For fenbufen complexes, there is a clear trend that the stability constant increases with the degree of substitution, while isomer purity has a smaller effect on the magnitude of stability constants.
Mazákné Dr. Kraszni Márta, Ferenc Agh, Daniel Horvath, Arash Mirzahosseini, Horváth Péter

See the full article here: Effect of Substitution Degree and Homogeneity on Cyclodextrin-Ligand Complex Stability: Comparison of Fenbufen and Fenoprofen Using CD and NMR Spectroscopy

Inclusion Complex Formation with Tetra-PEGylated Tetraphenylporphyrin and Face-to-Face Cyclodextrin Dimer through Unprecedented Molecular Threading

carbohydrates, drug development

Do cyclodextrin dimers hold the future of therapeutic CDs? Could be…

Herein, a host–guest inclusion complex formation between tetra-PEGylated tetraphenylporphyrin with a per-O-methylated cyclodextrin dimer through the molecular threading process that is physically unexpected to occur is described. Although the molecular size of the PEGylated porphyrin is much greater than that of the CD dimer, the sandwich-type porphyrin/CD dimer 1 : 1 inclusion complex was spontaneously formed in water. The ferrous porphyrin complex binds O2 reversibly in an aqueous solution, which functions as an artificial oxygen carrier in vivo. Pharmacokinetic study using rats revealed that the inclusion complex showed a long circulation in blood in contrast to the complex without PEG. The O2 adduct of the ferrous complex shows similar O2 binding affinity with natural hemoglobin and a long circulation time in blood, leading to the simple supramolecular complex that can be used as an artificial O2 carrier in vivo.
Doshisha University – Hiroaki Kitagishi and Qiyue Mao

See the full article here: Inclusion Complex Formation with Tetra-PEGylated Tetraphenylporphyrin and Face-to-Face Cyclodextrin Dimer through Unprecedented Molecular Threading

Polymerizable rotaxane hydrogels for three-dimensional printing fabrication of wearable sensors

Today's cyclodextrin,

today’s cyclodextrin:
It’s been just a few days since I heard a lecture that proposed using CDs in 3D printing pharma applications. In this paper from the South China University of Technology and Nanyang Technological University Singapore, 3D-printed wearable sensors are introduced.
While hydrogels enable a variety of applications in wearable sensors and electronic skins, they are susceptible to fatigue fracture during cyclic deformations owing to their inefficient fatigue resistance. In this work, acrylated β-cyclodextrin with bile acid is self-assembled into a polymerizable pseudorotaxane via precise host-guest recognition, which is photopolymerized with acrylamide to obtain conductive polymerizable rotaxane hydrogels (PR-Gel). The topological networks of PR-Gel enable all desirable properties in this system due to the large conformational freedom of the mobile junctions, including excellent stretchability along with superior fatigue resistance. PR-Gel-based strain sensors can sensitively detect and distinguish large body motions and subtle muscle movements. The three-dimensional printing fabricated sensors of PR-Gel exhibit high resolution and altitude complexity, and real-time human electrocardiogram signals are detected with high repeating stability. PR-Gel can self-heal in air, and has highly repeatable adhesion to human skin, demonstrating its great potential in wearable sensors.
#motionsensor #selfhealing

See the full article here: Polymerizable rotaxane hydrogels for three-dimensional printing fabrication of wearable sensors

Molecular Mind Games: The Medicinal Action of Cyclodextrins in Neurodegenerative Diseases

carbohydrates, ,

Cyclodextrins are often used as molecular carriers for small active ingredients in the medicine. Recently, the intrinsic medicinal activity of some of these compounds has been under investigation, mainly related to their ability to interfere with cholesterol and, therefore, prevent and treat cholesterol-related diseases such as cardiovascular disease and neuronal diseases arising from altered cholesterol and lipid metabolism. One of the most promising compounds within the cyclodextrin family is 2-hydroxypropyl-β-cyclodextrin (HPβCD), owing to its superior biocompatibility profile. This work presents the most recent advances in the research and clinical use of HPβCD against Niemann–Pick disease, a congenital condition involving cholesterol accumulation inside lysosomes in brain cells, Alzheimer’s and Parkinson’s. HPβCD plays a complex role in each of these ailments, going beyond the mere sequestering of cholesterol molecules and involving an overall regulation of protein expression that helps restore the normal functioning of the organism.
Fantastic review by Susana Santos Braga form Universidade de Aveiro

See the full article here: Molecular Mind Games: The Medicinal Action of Cyclodextrins in Neurodegenerative Diseases

Solid-State Preparation and Characterization of 2-Hydroxypropylcyclodextrins-Iodine Complexes as Stable Iodophors

Today's cyclodextrin

today’s cyclodextrin:
The use of iodine as antiseptic poses some issues related to its low water solubility and high volatility. Stable solid iodine-containing formulations are highly advisable and currently limited to the povidone-iodine complex. In this study, complexes of molecular iodine with 2-hydroxypropyl α-, β- and γ-cyclodextrins were considered water-soluble iodophors and prepared in a solid state by using three different methods (liquid-assisted grinding, co-evaporation, and sealed heating). The obtained solids were evaluated for their iodine content and stability over time in different conditions. High levels of iodine content (8.3-10.8%) were obtained with all the tested cyclodextrins, and some influence was exerted by the employed preparation method. Potential use as solid iodophors can be envisaged for these iodine complexes, among which those with 2-hydroxypropyl-α-cyclodextrin were found the most stable, regardless of the preparation technique. The three prepared cyclodextrin-iodine complexes proved effective as bactericides against S. epidermidis.
Sandro Dattilo, Fabiola Spitaleri, Danilo Aleo, Maria Grazia Saita, Angela Patti – MEDIVIS

See the full article here:Solid-State Preparation and Characterization of 2-Hydroxypropylcyclodextrins-Iodine Complexes as Stable Iodophors

Othon Moultos has been awarded an NWO OTP grant of 1 million euros for water treatment research

Today's cyclodextrin, ,

today’s cyclodextrin:
using CDs in wastewater treatment has been around for decades. Nowadays, this application is industrially pioneered by Cyclopure. This research field may experience a new booster, as Othonas Moultos of the Delft University of Technology received a 1M Euro award for his project “SYROP – Intelligent design of sustainable Sugar(cYclodextrin)-based adsorbents for the Removal of Organic microPollutants and PFAS from water’’ from NWO (Dutch Research Council).
The SYROP team also includes top researchers from the industry: Yuhan Ling, and Gokhan Barin from Cyclopure Dr. van der Hoeke from Waternet (the water utility of Amsterdam and surroundings), and de Jong and Dr. Nieuwenhuijzen from Wittenveen+Bos (a company with 4000+ projects experience in environmental engineering). SYROP will combine for the first time advanced molecular modeling, machine learning, and experimentation to design and develop a new generation of sustainable and efficient sugar-based adsorbents that can selectively remove high-priority harmful components during water treatment.

See the press release here

Othon Moultos


Well-Defined Heparin Mimetics Can Inhibit Binding of the Trimeric Spike of SARS-CoV-2 in a Length-Dependent Manner

carbohydrates, ,

Well-defined heparin mimetics that could inhibit the binding of the SARS-CoV-2 spike or RBD to immobilized heparin or to Vero E6 cells. The inhibitory potency increased with increasing chain length, and a compound composed of four sulfated hexasaccharides linked by triazoles had a similar potency as unfractionated heparin. The heparin mimetics exhibit no or reduced binding to antithrombin-III and platelet factor 4, respectively, which are associated with side effects.

Utrecht University – Roosmarijn van der Woude, Robert de Vries et al
The University of Georgia – Lin Liu et al

See the full article here