The extent of ionization of the polyamines is an important factor in their interactions with cellular components. The pK(a) is the pH at which a functional group is 50% ionized. For compounds such as polyamines with more than one ionizable center (atom or functional group), there is a pK(a) value for each center of ionization. This chapter describes the pK(a) values for each amine group in many important polyamines, the factors influencing these values and methods for their determination using potentiometric titration and nuclear magnetic resonance spectroscopy.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1007/978-1-61779-034-8_32 | DOI Listing |
Int J Biol Macromol
January 2025
Institute of Organic Chemistry and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstr. 10, D-07743 Jena, Germany; Jena Center for Soft Matters (JCSM), Friedrich Schiller University Jena, Philosophenweg 7, D-07743 Jena, Germany. Electronic address:
Nanomedicine, particularly gene delivery, holds immense potential and offers promising therapeutic options. Non-viral systems gained attention due to their binding capacity, stability and scalability. Among these, natural polysaccharides, such as pullulan, are advantageous in terms of sustainability, biocompatibility and potential degradability.
View Article and Find Full Text PDFEnviron Sci Technol
January 2025
Department of Energy, Environmental & Chemical Engineering Washington University in St. Louis, St. Louis, Missouri 63130, United States.
The hydrolysis rates of many organic chemicals are accelerated under alkaline conditions by the presence of hydroxide (HO), which is typically assumed to be the predominant species contributing to base-catalyzed hydrolysis in both natural waters and laboratory buffers used in standard protocols. In this study, we demonstrated that weak bases (e.g.
View Article and Find Full Text PDFBioconjug Chem
January 2025
Departments of Chemistry and Toxicology, University of Guelph, Guelph, Ontario N1G 2W1,Canada.
The ability to label synthetic oligonucleotides with fluorescent probes has greatly expanded their nanotechnological applications. To continue this expansion, it is essential to develop approachable, modular, and tunable fluorescent platforms. In this study, we present the synthesis and incorporation of an amino-formyl-thieno[3,2-]thiophene (AFTh) handle at the 5'-position of DNA oligonucleotides.
View Article and Find Full Text PDFJ Pharm Biomed Anal
January 2025
Sabanci University Nanotechnology Research and Application Center (SUNUM), Istanbul 34956, Turkey.
This study aimed to determine the chromatographic retention and dissociation/protonation constant (pK) values of lapatinib and tamoxifen, key drugs used in metastatic breast cancer treatment, at 37°C using both conventional and green high-performance liquid chromatography (HPLC) methods. Qualitative analysis was conducted on an XTerra C18 column (250 ×4.6 mm I.
View Article and Find Full Text PDFJ Chem Inf Model
January 2025
Max-Planck-Institut für Immunbiologie und Epigenetik (MPI-IE), Stübeweg 51, 79108 Freiburg im Breisgau, Germany.
Intrinsically disordered regions are found in most eukaryotic proteins and are enriched with positively and negatively charged residues. While it is often convenient to assume that these residues follow their model-compound p values, recent work has shown that local charge effects (charge regulation) can upshift or downshift side chain p values with major consequences for molecular function. Despite this, charge regulation is rarely considered when investigating disordered regions.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!