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The Journal of Physical and Colloid... Jan 1947
Topics: Molecular Weight
PubMed: 20286386
DOI: 10.1021/j150451a002 -
Polimery W Medycynie 2021Fucoidans represent the sulfated heteropolysaccharides that possess a wide range of important pharmacological properties. The properties of a fucoidan depend on several... (Review)
Review
Fucoidans represent the sulfated heteropolysaccharides that possess a wide range of important pharmacological properties. The properties of a fucoidan depend on several factors, including the molecular weight and the way of extraction. However, the selection of an optimal depolymerization method is necessary to enhance its therapeutic applications. Reducing the molecular weight of fucoidans will make it possible to use them in creating nanoparticles and nanocarriers for, among others, the targeted drug delivery. The molecular mass of the polymer can be changed by means of various methods of depolymerization. In this work, the possibility of application of ultrasonic destruction for decrease in the size of fucoidan molecules for the purpose of expansion of opportunities and spheres of their therapeutic application is considered. This is one of the simple and effective methods of depolymerization of fucoidan, which leads to a decrease in molecular weight without significant structural changes in macromolecules. In addition, methods and potential applications of the ultrasonic extraction of fucoidan from seaweed and the possibilities of their combination are discussed, as well as other physical or chemical methods of extraction.
Topics: Molecular Weight; Nanoparticles; Polysaccharides; Ultrasonics
PubMed: 34910386
DOI: 10.17219/pim/143961 -
Journal of Medicinal Chemistry Sep 2023Molecular complexity (MC) lacks a universal definition, but various studies address it in contexts ranging from ligand-receptor interactions to DNA sequencing, with the...
Molecular complexity (MC) lacks a universal definition, but various studies address it in contexts ranging from ligand-receptor interactions to DNA sequencing, with the overarching emphasis being its significance in synthetic organic chemistry and pharmaceutical research. Efforts to quantify MC in drug discovery have been numerous, but a unified approach remains challenging. Strategies based on graph theory, information theory, and substructural feature counts employed to gauge MC are often correlated to molecular weight (MW). Herbert Waldmann and his team introduced a new MC metric called the spacial score (SPS), which is based on factors like atom hybridization and stereoisomeric considerations. While SPS and its normalized version, nSPS, correlate with the natural product likeness score, they do not align with traditional chemical properties. We examined nSPS trends for approved drugs and found no significant changes in MC over eight decades, nor did nSPS capture drug innovation during that period. Furthermore, our analysis indicates that while the majority of approved drugs have an nSPS value between 10 and 20, this metric does not correlate with key drug properties like target bioactivity and oral bioavailability. Mirroring a chemist's intuitive sense of chemical complexity, nSPS addresses the need for a precise empirical tool while a universal definition of MC remains elusive.
Topics: Drug Discovery; Biological Products; Molecular Weight
PubMed: 37675804
DOI: 10.1021/acs.jmedchem.3c01507 -
Journal of Medicinal Chemistry Dec 2018Lead-like drugs, or drugs below molecular weight 300, are an important and sometimes overlooked component of the current pharmacopeia and contemporary medicinal... (Review)
Review
Lead-like drugs, or drugs below molecular weight 300, are an important and sometimes overlooked component of the current pharmacopeia and contemporary medicinal chemistry practice. To examine the recent state-of-the-art in lead-like drug discovery, we surveyed recent drug approvals from 2011 to 2017 and top 200 prescribed medications, as well as provide case studies on recently approved lead-like drugs. Many of these recent drugs are close analogs of previously known drugs or natural substrates, with a key focus of their medicinal chemistry optimization being the choice of a low molecular weight starting point and maintaining low molecular weight during the optimization. However, the identification of low molecular weight starting points may be limited by the availability of suitable low molecular weight screening sets. To increase the discovery rate of lead-like drugs, we suggest an increased focus on inclusion and prosecution of lead-like starting points in screening libraries.
Topics: Drug Discovery; Drug Evaluation, Preclinical; Molecular Weight
PubMed: 30052440
DOI: 10.1021/acs.jmedchem.8b00407 -
Biopolymers Jul 2015This work reports the molecular weight (MW) analysis of high MW dextran using multiangle light scattering (MALS) in both chromatography and automated batch measurement...
This work reports the molecular weight (MW) analysis of high MW dextran using multiangle light scattering (MALS) in both chromatography and automated batch measurement mode. The results show that the chromatographic columns alter the high MW native dextran and cause underestimation of the MW as a consequence. Alternatively, a batch MALS measurement (without columns) provides more accurate MW values. The batch MALS measurement was automated with the incorporation of an automatic sample dilution and injection device. This automation reduces the sample preparation time and minimizes concentration errors introduced by manual sample dilution. To the best of our knowledge, this is the first study using an automated batch MALS in the analysis of high MW dextran.
Topics: Chromatography, Gel; Dextrans; Molecular Weight
PubMed: 25808515
DOI: 10.1002/bip.22637 -
Revue International Des Services de... Jan 1965
Review
Topics: Blood Coagulation; Blood Group Antigens; Dextrans; Humans; Molecular Weight
PubMed: 14312169
DOI: No ID Found -
Minerva Anestesiologica Jul 2018
Topics: Abdominal Muscles; Analgesia; Dextrans; Molecular Weight; Nephrectomy
PubMed: 29589428
DOI: 10.23736/S0375-9393.18.12862-8 -
Biomedical Chromatography : BMC Oct 2002Commercially available hyaluronan (HA) samples were investigated by the method of size exclusion chromatography (SEC). The fractions eluted from the SEC column were...
Commercially available hyaluronan (HA) samples were investigated by the method of size exclusion chromatography (SEC). The fractions eluted from the SEC column were on-line molecularly characterized by using a multi-angle laser light scattering (MALLS) photometer. Along with the SEC-MALLS technique, the high-molecular-weight HA biopolymers were (off-line) analyzed by capillary viscometry.
Topics: Hyaluronic Acid; Molecular Weight; Spectrophotometry, Ultraviolet; Viscosity
PubMed: 12378558
DOI: 10.1002/bmc.185 -
Journal of Dental Research Feb 1989The influence of the molecular weight of the poly(acrylic acid) component on some properties of glass-ionomer cement has been investigated. The results can be explained...
The influence of the molecular weight of the poly(acrylic acid) component on some properties of glass-ionomer cement has been investigated. The results can be explained by treatment of glass-ionomer cements as thermoplastic composites. Many of the concepts of polymer science can be applied successfully in a qualitative way to these cements, including the ideas of entanglements and reptation. Molecular weight of the polyacid had a pronounced influence on setting rate, acid erosion rate, toughness, fracture toughness, and wear resistance. The chain length of the polyacid was found to be an important parameter in formulation of a cement, and the higher the molecular weight, the better the properties. However, in practice the molecular weight is limited by viscosity, and some balance has to be achieved among concentration, molecular weight, and viscosity.
Topics: Acrylates; Chemical Phenomena; Chemistry, Physical; Dental Cements; Glass Ionomer Cements; Molecular Weight; Surface Properties; Viscosity
PubMed: 2918140
DOI: 10.1177/00220345890680021401 -
Journal of Chromatography. A Dec 2021Understanding the relation between chemical characteristics and properties of synthetic polymers is one of the challenges faced by analytical chemists in industry. This...
Fast determination of functionality-type × molecular-weight distribution of propoxylates with varying numbers of hydroxyl end-groups using gradient-normal-phase liquid chromatography × ultra-high pressure size-exclusion chromatography.
Understanding the relation between chemical characteristics and properties of synthetic polymers is one of the challenges faced by analytical chemists in industry. This is a complex task, as polymers are not synthesized as single molecule, but are populations of chemically similar compounds with distributions over several properties. The latter include, for example, molecular weight, nature of end-groups (functionality), and chemical composition. In this paper, comprehensive two-dimensional liquid chromatography was used to determine the combined functionality-type and molecular-weight distributions of hydroxy‑functionalized propoxylates. Propoxylates derived from different initiators (one up to eight terminal hydroxyl groups) were separated in the first dimension using a gradient normal-phase LC separation (NPLC). In the second dimension ultra-high pressure size-exclusion chromatography separation (UHPSEC), further speciating distributions based on molecular size. The developed NPLC × SEC method with evaporative light-scattering detection can be used for the fast screening (< 30 min) of mutually dependent functionality-type and molecular-weight distributions of unknown propoxylates.
Topics: Chromatography, Gel; Chromatography, Liquid; Molecular Weight; Polymers
PubMed: 34739964
DOI: 10.1016/j.chroma.2021.462644