Aminoalkyl functionalization of dextran for coupling of bioactive molecules and nanostructure formation

2013 ◽  
Vol 95 (1) ◽  
pp. 569-577 ◽  
Author(s):  
Kathrin Fiege ◽  
Heinrich Lünsdorf ◽  
Petra Mischnick
Keyword(s):  
Bioactive Molecules ◽  
Nanostructure Formation

Wrinkling Poly(trimethylene 2,5-Furanoate) Free-standing Films: Nanostructure Formation and Physical Properties

2020 ◽  
Author(s):  
Michelina Soccio ◽  
Nadia Lotti ◽  
Andrea Munari ◽  
Esther Rebollar ◽  
Daniel E Martínez-Tong
Keyword(s):  
Irradiation Time ◽  
Polymer Surface ◽  
Laser Source ◽  
Free Standing ◽  
Force Microscopy ◽  
Nanostructure Formation ◽  
Physicochemical Changes ◽  
Angle Measurements ◽  
Atomic Force ◽  
Contact Angle Measurements

<p>Nanostructured wrinkles were developed on fully bio-based poly(trimethylene furanoate) (PTF) films by using the technique of Laser Induced Periodic Surface Structures (LIPSS). We investigated the effect of irradiation time on wrinkle formation using an UV pulsed laser source, at a fluence of 8 mJ/cm2. It was found that the pulse range between 600 and 4800 pulses allowed formation of periodic nanometric ripples. The nanostructured surface was studied using a combined macro- and nanoscale approach. We evaluated possible physicochemical changes taking place on the polymer surface after irradiation by infrared spectroscopy, contact angle measurements and atomic force microscopy. The macroscopic physicochemical properties of PTF showed almost no changes after nanostructure formation, differently from the results previously found for the terephthalic counterparts, as poly(ethyleneterephthalate), PET, and poly(trimethyleneterephthalate), PTT. The surface mechanical properties of the nanostructured PTF were found to be improved, as evidenced by nanomechanical force spectroscopy measurements. In particular, an increased Young’s modulus and higher stiffness for the nanostructured sample were measured. <br></p>

Bifluoride Ion Mediated SuFEx Trifluoromethylation of Sulfonyl Fluorides and Iminosulfur Oxydifluorides

2018 ◽  
Author(s):  
Christopher J. Smedley ◽  
Bing Gao ◽  
Suhua Li ◽  
Qinheng Zheng ◽  
Andrew Molino ◽  
...  
Keyword(s):  
Breast Cancer Cells ◽  
Catalytic Mechanism ◽  
Bioactive Molecules ◽  
Chromatographic Purification ◽  
Rapid Exchange ◽  
Nucleophilic Displacement ◽  
Sulfur Fluoride ◽  
Reactions With Nucleophiles ◽  
New Generation ◽  
Selection Of

Sulfur-Fluoride Exchange (SuFEx) is the new generation click chemistry transformation exploiting the unique properties of S-F bonds and their ability to undergo near-perfect reactions with nucleophiles. We report here the first SuFEx based protocol for the efficient synthesis of pharmaceutically important triflones and bis(trifluoromethyl)sulfur oxyimines from the corresponding sulfonyl fluorides and iminosulfur oxydifluorides, respectively. The new protocol involves the rapid exchange of the S-F bond with trifluoromethyltrimethylsilane (TMSCF<sub>3</sub>) upon activation with potassium bifluoride in anhydrous DMSO. The reaction tolerates a wide selection of substrates and proceeds under mild conditions without need for chromatographic purification. A tentative catalytic mechanism is proposed supported by DFT calculations, involving formation of the free trifluoromethyl anion followed by nucleophilic displacement of the S-F through a five-coordinate intermediate. The preparation of a benzothiazole derived bis(trifluoromethyl)sulfur oxyimine with cytotoxic selectivity for MCF7 breast cancer cells demonstrates the utility of this methodology for the late-stage functionalization of bioactive molecules.<br>

Reductive Cleavage of Secondary Sulfonamides: Converting Terminal Functional Groups into Versatile Synthetic Handles

2019 ◽  
Author(s):  
Patrick Fier ◽  
Suhong Kim ◽  
Kevin M. Maloney
Keyword(s):  
Functional Groups ◽  
Late Stage ◽  
Reductive Cleavage ◽  
Bioactive Molecules ◽  
General Method

Sulfonamides are pervasive in drugs and agrochemicals, yet are typically considered as terminal functional groups rather than synthetic handles. To enable the general late-stage functionalization of secondary sulfonamides, we have developed a mild and general method to reductively cleave the N-S bonds of sulfonamides to generate sulfinates and amines, components which can further react <i>in-situ</i> to access a variety of other medicinally relevant functional groups. The utility of this platform is highlighted by the selective manipulation of several complex bioactive molecules.

Antibiotic-anionic Clay Matrix Used for Drug Controlled Release

2018 ◽  
Vol 69 (2) ◽  
pp. 321-323
Author(s):  
Georgeta Zegan ◽  
Elena Mihaela Carausu ◽  
Loredana Golovcencu ◽  
Alina Sodor Botezatu ◽  
Eduard Radu Cernei ◽  
...  
Keyword(s):  
Controlled Release ◽  
Layered Double Hydroxides ◽  
Bioactive Molecules ◽  
Drug Controlled Release ◽  
Anionic Clays ◽  
Anionic Clay ◽  
Toxicological Studies ◽  
High Efficient ◽  
Clay Matrix ◽  
Double Hydroxides

Anionic clay matrix acting as drug controlled release system have shown in last years a great potential for delivery of bioactive molecules and chemical therapeutics. This organic-inorganic nanohybrid system is high efficient offering an excellent protection of intercalated compounds from degradation. Compared to other nanoparticles used in medical area, anionic clays type layered double hydroxides have found to be biocompatible according to toxicological studies. Ampicillin containing MgAlLDHs and ZnAlLDH samples have been prepared following two routes: anion-exchange procedure and reconstruction from calcined layered double hydroxides. Solid samples have been characterized by FTIR and SEM-EDX highlighting the alteration of pristine LDHs structure when the antibiotic is introduced in the interlayer gallery.

Role of Matrix Metalloproteinases in Degenerative Kidney Disorders

2018 ◽  
Vol 25 (15) ◽  
pp. 1805-1816 ◽  
Author(s):  
Shifa Narula ◽  
Chanderdeep Tandon ◽  
Simran Tandon
Keyword(s):  
Matrix Metalloproteinases ◽  
Transforming Growth Factor ◽  
Kidney Diseases ◽  
Transforming Growth Factor Β1 ◽  
Bioactive Molecules ◽  
Tissue Inhibitors Of Metalloproteinases ◽  
Ecm Remodeling ◽  
Surface Receptors ◽  
Calcium Dependent ◽  
Ecm Degradation

Matrix metalloproteinases (MMPs) are members of calcium dependent-zinc containing endopeptidases that play a pivotal role in extracellular matrix (ECM) remodeling. MMPs are also known to cleave non-matrix proteins, including cell surface receptors, TNF-α, angiotensin-II, growth factors, (especially transforming growth factor-β1, ΤGF- β1) plasminogen, endothelin and other bioactive molecules. The tissue inhibitors of metalloproteinases (TIMPs) inhibit the activity of MMPs and decrease ECM degradation. Various patho-physiological conditions have been linked with the imbalance of ECM synthesis and degradation. Numerous studies have reported the significance of MMPs and TIMPs in the progression of kidney pathologies, including glomerulonephritis, diabetic nephropathy, renal cancer, and nephrolithiasis. Although dysregulated activity of MMPs could directly or indirectly lead to pathological morbidities, their contribution in disease progression is still understated. Specifically, MMP activity in the kidneys and it's relation to kidney diseases has been the subject of a limited number of investigations. Therefore, the aim of the present review is to provide an updated insight of the involvement of MMPs and TIMPs in the pathogenesis of inflammatory and degenerative kidney disorders.

Advancing the Therapeutic Efficacy of Bioactive Molecules by Delivery Vehicle Platforms.

2020 ◽  
Vol 27 ◽  
Author(s):  
Antonis D. Tsiailanis ◽  
Andreas G. Tzakos ◽  
Thomas Mavromoustakos
Keyword(s):  
Gold Nanoparticles ◽  
Angiotensin Ii ◽  
Therapeutic Index ◽  
Bioactive Molecules ◽  
Host Molecule ◽  
Delivery Vehicle ◽  
Metabolic Products ◽  
Activity Enhancement ◽  
Technological Platforms ◽  
Low Solubility

: Drugs have to overcome numerous barriers to reach their desired therapeutic targets. In several cases drugs, especially the highly lipophilic molecules, suffer from low solubility and bioavailability and therefore their desired targeting is hampered. In addition, undesired metabolic products might be produced or off-targets could be recognized. Along these lines, nanopharmacology has provided new technological platforms, to overcome these boundaries. Specifically, numerous vehicle platforms such as cyclodextrins and calixarenes have been widely utilized to host lipophilic drugs such as antagonists of the angiotensin II AT1 receptor (AT1R), as well as quercetin and silibinin. The encapsulation of these drugs in supramolecules or other systems refines their solubility and metabolic stability, increases their selectivity and therefore decreases their effective dose and improves the therapeutic index. In this minireview we report on the formulations of Silibinin and AT1R antagonist candesartan in a 2-HP-β-cyclodextrin host molecule, which displayed enhanced cytotoxicity and increased silibinin’s and candesartan’s stability, respectively. Moreover we describe the encapsulation of quercetin in gold nanoparticles bearing a calixarene supramolecular host. Also the encapsulation of temozolomide in a calixarene nanocapsule has been described. Finally, we report on the activity enhancement that has been achieved upon using these formulations as well as the analytical and computational methods we used to characterize these formulations and explore the molecular interactions between the host and quest molecules.

Role of Exosomes in Photodynamic Anticancer Therapy

2020 ◽  
Vol 27 (40) ◽  
pp. 6815-6824 ◽  
Author(s):  
Yuan Jiang ◽  
Chuanshan Xu ◽  
Wingnang Leung ◽  
Mei Lin ◽  
Xiaowen Cai ◽  
...  
Keyword(s):  
Photodynamic Therapy ◽  
Basic Principle ◽  
Photochemical Reaction ◽  
Cell Communication ◽  
Anticancer Therapy ◽  
Bioactive Molecules ◽  
Promising Alternative ◽  
Tumor Tissues ◽  
Significant Attention

Photodynamic Therapy (PDT) is a promising alternative treatment for malignancies based on photochemical reaction induced by Photosensitizers (PS) under light irradiation. Recent studies show that PDT caused the abundant release of exosomes from tumor tissues. It is well-known that exosomes as carriers play an important role in cell-cell communication through transporting many kinds of bioactive molecules (e.g. lipids, proteins, mRNA, miRNA and lncRNA). Therefore, to explore the role of exosomes in photodynamic anticancer therapy has been attracting significant attention. In the present paper, we will briefly introduce the basic principle of PDT and exosomes, and focus on discussing the role of exosomes in photodynamic anticancer therapy, to further enrich and boost the development of PDT.

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