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International Journal of Biological... Mar 2022The application of industrial kraft lignin is limited by its low molecular weight, dark color, and low solubility. In this work, an efficient crosslinking reaction with...
The application of industrial kraft lignin is limited by its low molecular weight, dark color, and low solubility. In this work, an efficient crosslinking reaction with N,N-Dimethylformamide (DMF) and 1,6-dibromohexane was proposed for adjusting the molecular weight and color of lignin. The chemical structure of alkylation lignin was systematically investigated by gel permeation chromatography (GPC), ultraviolet spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, and 2D heteronuclear single quantum correlation nuclear magnetic resonance (HSQC NMR) spectra. After the alkylation modification, the molecular weights of the lignin were increased to 1643%. The resinol (β-β), β-aryl ether (β-O-4), and phenylcoumaran (β-5) linkages were still the main types of the linkages. The formation of β-β linkage would be inhibited at high temperatures. The color reduction of lignin can be attributed to the low content of chromophores and low packing density. This alkylation lignin will be a new and general approach for developing molecular weight-controlled and light-colored lignins, which can find more applications in cosmetics, packing, and other fields.
Topics: Alkylation; Chromatography, Gel; Lignin; Molecular Structure; Molecular Weight; Spectroscopy, Fourier Transform Infrared
PubMed: 34995668
DOI: 10.1016/j.ijbiomac.2021.12.162 -
International Journal of Molecular... Mar 2023High molecular weight (MW), highly repetitive protein polymers are attractive candidates to replace petroleum-derived materials as these protein-based materials (PBMs)... (Review)
Review
High molecular weight (MW), highly repetitive protein polymers are attractive candidates to replace petroleum-derived materials as these protein-based materials (PBMs) are renewable, biodegradable, and have outstanding mechanical properties. However, their high MW and highly repetitive sequence features make them difficult to synthesize in fast-growing microbial cells in sufficient amounts for real applications. To overcome this challenge, various methods were developed to synthesize repetitive PBMs. Here, we review recent strategies in the construction of repetitive genes, expression of repetitive proteins from circular mRNAs, and synthesis of repetitive proteins by ligation and protein polymerization. We discuss the advantages and limitations of each method and highlight future directions that will lead to scalable production of highly repetitive PBMs for a wide range of applications.
Topics: Polymers; Molecular Weight; Proteins; Repetitive Sequences, Nucleic Acid
PubMed: 37047388
DOI: 10.3390/ijms24076416 -
Journal of Peptide Science : An... Jun 2023We aimed to determine the coacervation properties of high-molecular-weight (HMW) tissue-derived elastin (TDE) and to examine the potential use of TDE particles as a...
We aimed to determine the coacervation properties of high-molecular-weight (HMW) tissue-derived elastin (TDE) and to examine the potential use of TDE particles as a cosmetic biomaterial. TDE solutions were filtered and divided into three fractions (1-3) according to the molecular weight of the elastin. The turbidity of fraction 2, which contained a large portion (58%) of HMW elastin polypeptides (>100 kDa), was measured under several pH values (3.0-11.0) and NaCl concentrations (0-1000 mM) to examine its coacervation ability. HMW TDE exhibited coacervation under the physiological conditions (temperature, pH, and NaCl concentration) of the skin surface. We performed inclusion and release experiments using three model chemicals with different molecular weights and measured the size and zeta potential of the fraction 3 particles to investigate the suitability of HMW elastin polypeptides. Fraction 3, which contained a larger portion (64%) of HMW elastin polypeptides, displayed a strong coacervation property at a phase transition temperature of 19.8 ± 0.1°C. The inclusion ratio of the model chemical Biebrich Scarlet (BS) with a molecular weight of <600 was approximately 92.1 ± 0.7%. The release profiles of BS from the particles linearly increased and reached a plateau after 15 days. Moreover, the average size of the particles with BS was 474.2 ± 24.6 nm. The low-molecular-weight (LMW) elastin peptides have moisturizing and whitening functions for the skin. We concluded that TDE, as a mixture of HMW polypeptides and LMW peptides, can potentially serve as a multifunctional and effective cosmetic biomaterial.
Topics: Elastin; Molecular Weight; Sodium Chloride; Peptides; Temperature
PubMed: 36541737
DOI: 10.1002/psc.3472 -
Nanoscale Mar 2022Over the last twenty years, low-molecular weight gelators and, in particular, peptide-based hydrogels, have drawn great attention from scientists thanks to both their... (Review)
Review
Over the last twenty years, low-molecular weight gelators and, in particular, peptide-based hydrogels, have drawn great attention from scientists thanks to both their inherent advantages in terms of properties and their high modularity (, number and nature of the amino acids). These supramolecular hydrogels originate from specific peptide self-assembly processes that can be driven, modulated and optimized specific chemical modifications brought to the peptide sequence. Among them, the incorporation of nucleobases, another class of biomolecules well-known for their abilities to self-assemble, has recently appeared as a new promising and burgeoning approach to finely design supramolecular hydrogels. In this minireview, we would like to highlight the interest, high potential, applications and perspectives of these innovative and emerging low-molecular weight nucleopeptide-based hydrogels.
Topics: Amino Acid Sequence; Amino Acids; Hydrogels; Molecular Weight; Peptides
PubMed: 35319034
DOI: 10.1039/d1nr06131c -
Methods in Molecular Biology (Clifton,... 2022Glycosaminoglycan samples are usually polydisperse, consisting of molecules with differing length and differing sequence. Methods for measuring the molecular weight of...
Glycosaminoglycan samples are usually polydisperse, consisting of molecules with differing length and differing sequence. Methods for measuring the molecular weight of heparin have been developed to assure the quality and consistency of heparin products for medicinal use, and these methods can be applied in other laboratory contexts. In the method described here, high-performance gel permeation chromatography is calibrated using appropriate heparin molecular weight markers or a single broad standard calibrant and used to characterize the molecular weight distribution of polydisperse samples or the peak molecular weight of monodisperse, or approximately monodisperse, heparin fractions. The same technology can be adapted for use with other glycosaminoglycans.
Topics: Chromatography, Gel; Glycosaminoglycans; Hematologic Tests; Heparin; Heparitin Sulfate; Molecular Weight
PubMed: 34626382
DOI: 10.1007/978-1-0716-1398-6_18 -
Food Chemistry Aug 2022Arabinoxylans are important for dough and breadmaking properties. It is not clear how arabinoxylans of different molecular weights behave during the breadmaking process...
Arabinoxylans are important for dough and breadmaking properties. It is not clear how arabinoxylans of different molecular weights behave during the breadmaking process as well as the changes in individual structures. We investigated changes in the molecular weight and structure of water-extractable arabinoxylans. It was revealed that molecules larger than high molecular weight arabinoxylans were formed during the mixing and 1st fermentation (105 min before 1st punch). High molecular weight arabinoxylan continued to be degraded from mixing to the proofing stage. The arabinose to xylose ratio increased at mixing and the 1st fermentation due to solubilization of highly substituted arabinoxylan. Low molecular weight arabinoxylan did not show degradation and structural changes during the fermentation process, whereas the weight average molecular weight of low molecular weight arabinoxylan significantly decreased (P < 0.05) at mixing. Water extractable arabinoxylan shows different behaviors for molecular weight and structural changes during the breadmaking process.
Topics: Bread; Flour; Molecular Weight; Secale; Water; Xylans
PubMed: 35344729
DOI: 10.1016/j.foodchem.2022.132772 -
Chemical Communications (Cambridge,... Jan 2023The field of sustainable polymers from renewable feedstocks is a fast-reviving field after the decades-long domination of petroleum-based polymers. Amide-containing... (Review)
Review
The field of sustainable polymers from renewable feedstocks is a fast-reviving field after the decades-long domination of petroleum-based polymers. Amide-containing polymers exhibit a wide range of properties depending on the type of amide (primary, secondary, and tertiary), amide density, and other molecular structural parameters (co-existing groups, molecular weight, and topology). Engineering amide groups into sustainable polymers the "monomer approach" is an industrially proven strategy, while bio-based monomers are of enormous importance to bridge the gap between renewable sources and amide-containing sustainable polymers (AmSPs). This feature article aims at conceptualizing the monomer-design philosophy behind most of the reported AmSPs and is organized by discussing di-functional monomers for step-growth polymerization, cyclic monomers for ring-opening polymerization and amide-containing monomers for chain-growth polymerization. We also give a perspective on AmSPs with respect to monomer design and performance enhancement.
Topics: Polymers; Amides; Polymerization; Molecular Weight
PubMed: 36524867
DOI: 10.1039/d2cc05161c -
Journal of Medicinal Chemistry Feb 2023For oral drugs, medicinal chemists aim to design compounds with high oral bioavailability, of which permeability is a key determinant. Taking advantage of >2000... (Review)
Review
For oral drugs, medicinal chemists aim to design compounds with high oral bioavailability, of which permeability is a key determinant. Taking advantage of >2000 compounds tested in rat bioavailability studies and >20,000 compounds tested in Caco2 assays at Bayer, we have examined the molecular properties governing bioavailability and permeability. In addition to classical parameters such as logD and molecular weight, we also investigated the relationship between calculated p and permeability. We find that neutral compounds retain permeability up to a molecular weight limit of 700, while stronger acids and bases are restricted to weights of 400-500. We also investigate trends for common properties such as hydrogen bond donors and acceptors, polar surface area, aromatic ring count, and rotatable bonds, including compounds which exceed Lipinski's rule of five (Ro5). These property-structure relationships are combined to provide design guidelines for bioavailable drugs in both traditional and "beyond rule of 5" (bRo5) chemical space.
Topics: Humans; Rats; Animals; Biological Availability; Caco-2 Cells; Permeability; Hydrogen Bonding; Molecular Weight
PubMed: 36752336
DOI: 10.1021/acs.jmedchem.2c01577 -
Vaccine Jun 2021High Performance Size-Exclusion Chromatography coupled with Multi-Angle Light Scattering detection (HPSEC-MALS) is an important tool to provide a reliable molecular...
High Performance Size-Exclusion Chromatography coupled with Multi-Angle Light Scattering detection (HPSEC-MALS) is an important tool to provide a reliable molecular weight measurement for a large complex biomolecule. A recent HIV-1 soluble envelope trimer vaccine candidate, BG505 DS-SOSIP.664, is among the most glycosylated proteins to enter a clinical trial to date, and determination of its protein and glycan molecular weight is one of the key attributes in pre-clinical characterization. However, protein and glycans possess disparate dndcvalues making molecular weight measurement inaccurate in conventional SEC-MALS. To overcome these challenges, a simple mathematically guided experiment was explored, and a composite dndcvalue was established by utilizing protein and glycan mass contributions for the HIV-1 envelope trimer. This establishment was further verified by an orthogonal mass spectrometry analysis. This innovative, simple, and quick analytical approach can be applied broadly to measuring the molecular weight of various composite molecular structures, such as complex glycoconjugates.
Topics: Antibodies, Neutralizing; HIV Antibodies; HIV-1; Molecular Weight; Polysaccharides; Protein Multimerization; env Gene Products, Human Immunodeficiency Virus
PubMed: 34053790
DOI: 10.1016/j.vaccine.2021.05.048 -
ASAIO Journal (American Society For... Feb 2023A novel extracorporeal circuit for hemodialysis is described, which enhances the removal of middle- and high-molecular-weight toxins. To enhance the removal of...
A novel extracorporeal circuit for hemodialysis is described, which enhances the removal of middle- and high-molecular-weight toxins. To enhance the removal of especially high-molecular toxins, a recirculation pathway for dialysate flow is added to conventional circuit. The influence of an increase in the ratio of recirculation to dialysate flow rate and the ultrafiltration rate (UFR) on the removal of toxins was investigated to evaluate the removal of different toxins in clinical conditions. Removal of toxins was also modeled by an analytical method and solved by the MATLAB software (The MathWorks, Inc., Natick, MA). A significant increase in removal of urea (up to 31%) and vitamin B12 (11%) was achieved when the UFR is low (≤50 ml/h) or zero. The model showed an excellent agreement with the experimental results, which indicates its applicability for the removal of different toxins in an extracorporeal circuit. Increase in recirculation flow, while adjusting the UFR near zero, improves the mass transfer coefficient and can lead to enhanced especially middle- and high-molecular-weight toxin removal.
Topics: Dialysis; Renal Dialysis; Dialysis Solutions; Ultrafiltration; Molecular Weight
PubMed: 35417444
DOI: 10.1097/MAT.0000000000001731