Hyaluronic acid (HA) is applied in a number of medical applications and HA of different molecular weight (Mw) are used in different pharmaceutical preparations. In determination of Mw by muti-angle laser light-scattering (MALS), refractive index increment (dn/dc) is an important parameter for accuracy. Herein, the influence of dn/dc on the Mw of HA in stroke-physiological saline solution is investigated by MALS in this work. Additionally, the Mw variation of HA in the manufacturing process of preparations is measured. It is shown that each HA sample corresponds to a specific value of dn/dc, which is varied from 1.38 to 1.74 L/g with the Mw increasing from 13.5 to 2840 kDa in solution. It is indicated by the results from both MALS approach and viscometry that appropriate dn/dc should be selected for Mw determination. In steam sterilization process of preparations at 121 °C, the Mw and conformation of HA can be accurately and rapidly determined by MALS. This work provides a precise method to determine the Mw of HA in the medical applications and preparation industries.
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http://dx.doi.org/10.1038/s41598-020-58992-7 | DOI Listing |
Graefes Arch Clin Exp Ophthalmol
December 2024
Eye Ear Nose and Throat Hospital, Fudan University, XuHui District, No. 19 BaoQing Road, Shanghai, 200031, China.
Purpose: This study aimed to measure the changes in refraction difference value (RDV) in different parts of the retina before and after implantable collamer lenses (ICL) surgery.
Design: Prospective study.
Methods: This study included 40 eyes of 40 patients who underwent ICL implantation for myopia.
Spectrochim Acta A Mol Biomol Spectrosc
November 2024
Department of Physics, Indian Institute of Technology Kharagpur, Kharagpur 721302, India. Electronic address:
Serotonin is an important biogenic monoamine neurotransmitter that has major influences on mental health disorders; its structural and conformational changes have important roles in the biological functions of the human body. The decreased serotonin levels in the human body are majorly attributed to the causes of anxiety, depressive disorders, mood disorders, etc. Therefore, the quantification of serotonin in our bodies is of utmost importance in unearthing the origin of such physiological disorders.
View Article and Find Full Text PDFClin Ophthalmol
November 2024
Department of Ophthalmology, University of Sao Paulo, São Paulo, SP, Brazil.
Purpose: Validate a novel approach for assessing residual astigmatism's impact on visual acuity in pseudophakic patients using defocus curves and spherical equivalent compensation.
Materials And Methods: Thirteen patients over 40 with cataracts and normal ophthalmological examinations were enrolled in a prospective, non-randomized cohort study. The defocus curve method was employed, wherein visual acuity was measured with spherical lenses ranging from -2.
Sci Rep
November 2024
Guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and Devices, School of Information and Optoelectronic Science and Engineering, South China Normal University, Guangzhou, 510006, China.
In this study, we propose a superior coherent perfect absorber and laser (CPA laser) constructed from the one-dimensional (1D) two-material (TM) parity-time (PT) symmetric periodic ring optical waveguide network (PROWN). A novel method based on seeking the exact extremum spontaneous PT-symmetric breaking points is used for determining the imaginary part of the refractive indices of the materials composed of waveguides. The minimal overall output coefficient [Formula: see text] and maximal transmissivity [Formula: see text] can reach [Formula: see text] and [Formula: see text], respectively, which are 9 orders of magnitude smaller and larger than the previously reported values, respectively.
View Article and Find Full Text PDFJ Acoust Soc Am
November 2024
School of Physical Science and Technology, Soochow University, Suzhou 215006, China.
Phase gradient metagratings (PGMs) reshape the impinging wavefront though the interplay between the linear adjacent phase increment inside supercells and the grating diffraction of supercells. However, the adjacent phase increment is elaborately designed by tuning the resonance of each subcell at a certain target frequency, which inevitably confines PGMs to operate only at the single frequency in turn. We notice that there exists a freedom of phase choice with a multi-2π increment in a supercell of PGMs, whereas conventional designs focus on the 2π increment.
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