scholarly journals Hydrodynamic Compatibility of Hyaluronic Acid and Tamarind Seed Polysaccharide as Ocular Mucin Supplements

Polymers ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2272
Author(s):  
Taewoo Chun ◽  
Thomas MacCalman ◽  
Vlad Dinu ◽  
Sara Ottino ◽  
Mary K. Phillips-Jones ◽  
...  
Keyword(s):  
Hyaluronic Acid ◽  
Keratoconjunctivitis Sicca ◽  
Sedimentation Coefficient ◽  
Size Exclusion ◽  
Random Coil ◽  
Hydrodynamic Characteristics ◽  
Tamarind Seed ◽  
Exclusion Chromatography ◽  
Seed Gum ◽  
Aggregation Phenomenon

Hyaluronic acid (HA) has been commonly used in eyedrop formulations due to its viscous lubricating properties even at low concentration, acting as a supplement for ocular mucin (principally MUC5AC) which diminishes with aging in a condition known as Keratoconjunctivitis sicca or “dry eye”. A difficulty has been its short residence time on ocular surfaces due to ocular clearance mechanisms which remove the polysaccharide almost immediately. To prolong its retention time, tamarind seed gum polysaccharide (TSP) is mixed as a helper biopolymer with HA. Here we look at the hydrodynamic characteristics of HA and TSP (weight average molar mass Mw and viscosity η) and then explore the compatibility of these polymers, including the possibility of potentially harmful aggregation effects. The research is based on a novel combination of three methods: sedimentation velocity in the analytical ultracentrifuge (SV-AUC), size-exclusion chromatography coupled to multiangle light scattering (SEC-MALS) and capillary viscometry. HA and TSP were found to have Mw=(680±30) kg/mol and (830±30) kg/mol respectively, and η=1475±30 ml/g and 675±20 ml/g, respectively. The structure of HA ranges from a rodlike molecule at lower molar masses changing to a random coil for Mw > 800 kg/mol, based on the Mark–Houwink–Kuhn–Sakurada (MHKS) coefficient. TSP, by contrast, is a random coil across the range of molar masses. For the mixed HA-TSP systems, SEC-MALS indicates a weak interaction. However, sedimentation coefficient (s) distributions obtained from SV-AUC measurements together with intrinsic viscosity demonstrated no evidence of any significant aggregation phenomenon, reassuring in terms of eye-drop formulation technology involving these substances.

Photodegradation of hyaluronic acid: EPR and size exclusion chromatography study

Biopolymers ◽  
1991 ◽  
Vol 31 (12) ◽  
pp. 1429-1435 ◽  
Author(s):  
L'. Lap??�k ◽  
P. Chabre??ek ◽  
A. Sta??ko
Keyword(s):  
Hyaluronic Acid ◽  
Size Exclusion Chromatography ◽  
Size Exclusion ◽  
Exclusion Chromatography

scholarly journals Validation of an Analytical Method for the Simultaneous Determination of Hyaluronic Acid Concentration and Molecular Weight by Size-Exclusion Chromatography

Molecules ◽  
2021 ◽  
Vol 26 (17) ◽  
pp. 5360
Author(s):  
Luis Antonio Suárez-Hernández ◽  
Rosa María Camacho-Ruíz ◽  
Enrique Arriola-Guevara ◽  
Eduardo Padilla-Camberos ◽  
Manuel Reinhart Kirchmayr ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Hyaluronic Acid ◽  
Size Exclusion Chromatography ◽  
Pharmaceutical Products ◽  
Global Market ◽  
Size Exclusion ◽  
Chromatography Method ◽  
Market Growth ◽  
Exclusion Chromatography ◽  
Repeatability And Reproducibility

The hyaluronic acid (HA) global market growth can be attributed to its use in medical, cosmetic, and pharmaceutical applications; thus, it is important to have validated, analytical methods to ensure confidence and security of its use (and to save time and resources). In this work, a size-exclusion chromatography method (HPLC-SEC) was validated to determine the concentration and molecular distribution of HA simultaneously. Analytical curves were developed for concentration and molecular weight in the ranges of 100–1000 mg/L and 0.011–2.200 MDa, respectively. The HPLC-SEC method showed repeatability and reproducibility greater than 98% and limits of detection and quantification of 12 and 42 mg/L, respectively, and was successfully applied to the analysis of HA from a bacterial culture, as well as cosmetic, and pharmaceutical products.

Equilibrium unfolding studies of the rat liver methionine adenosyltransferase III, a dimeric enzyme with intersubunit active sites

2002 ◽  
Vol 361 (2) ◽  
pp. 307-315 ◽  
Author(s):  
María GASSET ◽  
Carlos ALFONSO ◽  
José L. NEIRA ◽  
Germán RIVAS ◽  
María A. PAJARES
Keyword(s):  
Free Energy ◽  
Rat Liver ◽  
Active Sites ◽  
Analytical Ultracentrifugation ◽  
Sedimentation Coefficient ◽  
Methionine Adenosyltransferase ◽  
Size Exclusion ◽  
Activity Measurements ◽  
Exclusion Chromatography ◽  
Monomeric Intermediate

The reversible unfolding of rat liver methionine adenosyltransferase dimer by urea under equilibrium conditions has been monitored by fluorescence spectroscopy, CD, size-exclusion chromatography, analytical ultracentrifugation and enzyme activity measurements. The results obtained indicate that unfolding takes place through a three-state mechanism, involving an inactive monomeric intermediate. This intermediate has a 70% native secondary structure, binds less 8-anilinonaphthalene-1-sulphonic acid than the native dimer and has a sedimentation coefficient of 4.24±0.15. The variations of free energy in the absence of denaturant [ΔG(H2O)] and its coefficients of urea dependence (m), calculated by the linear extrapolation model, were 36.15±2.3kJ·mol−1 and 19.87±0.71kJ·mol−1·M−1 for the dissociation of the native dimer and 14.77±1.63kJ·mol−1 and 5.23±0.21kJ·mol−1·M−1 for the unfolding of the monomeric intermediate respectively. Thus the global free energy change in the absence of denaturant and the m coefficient were calculated to be 65.69kJ·mol−1 and 30.33kJ·mol−1·M−1 respectively. Analysis of the calculated thermodynamical parameters indicate the instability of the dimer in the presence of denaturant, and that the major exposure to the solvent is due to dimer dissociation. Finally, a minimum-folding mechanism for methionine adenosyltransferase III is established.

scholarly journals Size and conformation of Ficoll as determined by size-exclusion chromatography followed by multiangle light scattering

2010 ◽  
Vol 298 (1) ◽  
pp. F205-F208 ◽  
Author(s):  
William H. Fissell ◽  
Christina L. Hofmann ◽  
Ross Smith ◽  
Michelle H. Chen
Keyword(s):  
Light Scattering ◽  
Size Exclusion Chromatography ◽  
Conformational Changes ◽  
Physiological Saline ◽  
Transport Processes ◽  
Size Exclusion ◽  
Random Coil ◽  
Filtration Barrier ◽  
Exclusion Chromatography

The characteristics of the glomerular filtration barrier (GFB) are challenging to measure, as macromolecular solutes in blood may be metabolized or transported by various cells in the kidney. Urinary solute concentrations generally reflect the cumulative influence of multiple transport processes rather than the intrinsic behavior of the GFB alone. Synthetic tracer molecules which are not secreted, absorbed, or modified by the kidney are useful tools. Ficoll, a globular polymer of epichlorohydrin and sucrose, is round, physiologically inert, and easily labeled, making it a nearly ideal glomerular probe. Fissell et al. reported filtration data suggesting that Ficoll was not as spherical as had been previously suggested (Fissell WH, Manley S, Dubnisheva A, Glass J, Magistrelli J, Eldridge AN, Fleischman AJ, Zydney AL, Roy S. Am J Physiol Renal Physiol 293: F1209–F1213, 2007). More recently, two investigators published comparisons of neutral and anionic Ficoll clearance that suggest Ficoll may undergo conformational changes when chemically derivatized (Asgeirsson D, Venturoli D, Rippe B, Rippe C. Am J Physiol Renal Physiol 291: F1083–F1089, 2006; Guimaraes MAM, Nikolovski J, Pratt LM, Greive K, Comper WD. Am J Physiol Renal Physiol 285: F1118–F1124, 2003). To investigate Ficoll's characteristics further, we examined two commercial preparations, Ficoll 70 and Ficoll 400, by size-exclusion chromatography using a differential refractive index detector combined with light-scattering and viscosity detectors. A slope of 0.45 was obtained from the plot of the logarithm of molecular mass against the logarithm of root-mean square radius. The Mark-Houwink exponent values of 0.34 and 0.36 were calculated for Ficoll 70 and Ficoll 400, respectively. These results suggest Ficoll's conformation in physiological saline solution is likely intermediate between a solid sphere and a well-solvated linear random coil. The measurements help explain our previous observations and guide interpretation of in vivo experiments.

Purification and Characterization of Microbial Hyaluronic Acid by Solvent Precipitation and Size-Exclusion Chromatography

2009 ◽  
Vol 44 (4) ◽  
pp. 906-923 ◽  
Author(s):  
Anayla S. Sousa ◽  
Artemízia P. Guimarães ◽  
Caroline V. Gonçalves ◽  
Ivanildo J. Silva ◽  
Celio L. Cavalcante ◽  
...  
Keyword(s):  
Hyaluronic Acid ◽  
Size Exclusion Chromatography ◽  
Size Exclusion ◽  
Purification And Characterization ◽  
Exclusion Chromatography

scholarly journals Structural Features and Rheological Properties of a Sulfated Xylogalactan-Rich Fraction Isolated from Tunisian Red Seaweed Jania adhaerens

2020 ◽  
Vol 10 (5) ◽  
pp. 1655 ◽  
Author(s):  
Faiez Hentati ◽  
Cédric Delattre ◽  
Christine Gardarin ◽  
Jacques Desbrières ◽  
Didier Le Cerf ◽  
...  
Keyword(s):  
Rheological Properties ◽  
Flow Characteristics ◽  
Structural Features ◽  
Sulfated Polysaccharide ◽  
Size Exclusion ◽  
Random Coil ◽  
Precipitation Process ◽  
Resonance Spectroscopy ◽  
Exclusion Chromatography ◽  
Average Molecular Masses

A novel sulfated xylogalactan-rich fraction (JSP for J. adhaerens Sulfated Polysaccharide) was extracted from the red Tunisian seaweed Jania adhaerens. JSP was purified using an alcoholic precipitation process and characterized by Attenuated Total Reflectance-Fourier-transform infrared spectroscopy (ATR-FTIR), high-pressure size exclusion chromatography (HPSEC) with a multi-angle laser light scattering (MALLS), gas chromatography coupled to mass spectrometry (GC-MS) and nuclear magnetic resonance spectroscopy (NMR, 1D and 2D). JSP was then evaluated regarding its physicochemical and rheological properties. Results showed that JSP was mainly composed of an agar-like xylogalactan sharing the general characteristics of corallinans. The structure of JSP was mainly composed of agaran disaccharidic repeating units (→3)-β-d-Galp-(1,4)-α-l-Galp-(1→)n and (→3)-β-d-Galp-(1,4)-3,6-α-l-AnGalp-(1→)n, mainly substituted on O-6 of (1,3)-β-d-Galp residues by β-xylosyl side chains, and less with sulfate or methoxy groups. (1,4)-α-l-Galp residues were also substituted by methoxy and/or sulfate groups in the O-2 and O-3 positions. Mass-average and number-average molecular masses (Mw) and (Mn), intrinsic viscosity ([η]) and hydrodynamic radius (Rh) for JSP were, respectively, 8.0 × 105 g/mol, 1.0 × 105 g/mol, 76 mL/g and 16.8 nm, showing a flexible random coil conformation in solution. The critical overlap concentration C* of JSP was evaluated at 7.5 g/L using the Williamson model. In the semi-diluted regime, JSP solutions displayed a shear-thinning behavior with a great viscoelasticity character influenced by temperature and monovalent salts. The flow characteristics of JSP were described by the Ostwald model.

scholarly journals A Rapid Crosslinkable Maleimide-Modified Hyaluronic Acid and Gelatin Hydrogel Delivery System for Regenerative Applications

Gels ◽  
2021 ◽  
Vol 7 (1) ◽  
pp. 13
Author(s):  
Kyung Min Yoo ◽  
Sean V. Murphy ◽  
Aleksander Skardal
Keyword(s):  
Tissue Engineering ◽  
Extracellular Matrix ◽  
Hyaluronic Acid ◽  
Regenerative Medicine ◽  
Cell Encapsulation ◽  
Dermal Fibroblasts ◽  
Size Exclusion ◽  
Proton Nuclear Magnetic Resonance ◽  
Functional Requirements ◽  
Exclusion Chromatography

Hydrogels have played a significant role in many applications of regenerative medicine and tissue engineering due to their versatile properties in realizing design and functional requirements. However, as bioengineered solutions are translated towards clinical application, new hurdles and subsequent material requirements can arise. For example, in applications such as cell encapsulation, drug delivery, and biofabrication, in a clinical setting, hydrogels benefit from being comprised of natural extracellular matrix-based materials, but with defined, controllable, and modular properties. Advantages for these clinical applications include ultraviolet light-free and rapid polymerization crosslinking kinetics, and a cell-friendly crosslinking environment that supports cell encapsulation or in situ crosslinking in the presence of cells and tissue. Here we describe the synthesis and characterization of maleimide-modified hyaluronic acid (HA) and gelatin, which are crosslinked using a bifunctional thiolated polyethylene glycol (PEG) crosslinker. Synthesized products were evaluated by proton nuclear magnetic resonance (NMR), ultraviolet visibility spectrometry, size exclusion chromatography, and pH sensitivity, which confirmed successful HA and gelatin modification, molecular weights, and readiness for crosslinking. Gelation testing both by visual and NMR confirmed successful and rapid crosslinking, after which the hydrogels were characterized by rheology, swelling assays, protein release, and barrier function against dextran diffusion. Lastly, biocompatibility was assessed in the presence of human dermal fibroblasts and keratinocytes, showing continued proliferation with or without the hydrogel. These initial studies present a defined, and well-characterized extracellular matrix (ECM)-based hydrogel platform with versatile properties suitable for a variety of applications in regenerative medicine and tissue engineering.

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