Dosimetric characteristics and applications of cross-linking and degradation of a natural biopolymer Gum Acacia

AbstractThe current study covers the effect of gamma rays on a natural biopolymer Gum Arabic (GA). Gum acacia has a very wide range applications in various fields, that a comparison between two dosimetry systems; the first system depends on the radiolysis of GA (mixing poly-vinyl alcohol) as a thin-film dosimeter. The second system depends on the same material GA as solutions dosimeter, which is more sensitive to γ-radiation due to free mobility of free radicals released by the action of gamma rays. The prepared GA/film/solutions have a considerable peak at 289 nm, which increases (cross-linking of GA polymer) upon irradiation until 28 and 6 kGy for two systems, respectively in case of the first step. However, upon increased the absorbed doses and the intensity of the signal decrease with increasing radiation dose (degradation of GA polymer) up to 80 and 15 kGy for film and solutions. Radiation chemical yield G-(value); dose-response function; gamma radiation sensitivity; also pre- and post-irradiation stability under various conditions were illustrated.

Download Full-text

Radiation induced degradation of murexide dye in two media for possible use in dosimetric applications

Pigment & Resin Technology ◽

10.1108/prt-02-2019-0014 ◽

2019 ◽

Vol 48 (6) ◽

pp. 540-546 ◽

Cited By ~ 2

Author(s):

Sameh Mohamed Gafar ◽

Nehad Magdy Abdel-Kader

Keyword(s):

Gamma Rays ◽

Gamma Ray ◽

Absorbed Dose ◽

Chemical Yield ◽

Radiation Sensitivity ◽

Industrial Applications ◽

Food Irradiation ◽

Radiation Chemical ◽

Content Type ◽

Wide Range

Purpose The purpose of this paper is to study the effect of gamma-rays on murexide (Mx) dye and its possible use as radiation dosimeters in two different dosimetry systems. The first system depends on the Mx dye as a liquid dosimeter. The second dosimetry system depends also on the same dye but as in a gel form, which is more sensitive to gamma-rays. Design/methodology/approach The prepared Mx (solutions/gels) have a considerable two peaks at 324 and 521 nm that upon irradiation, the intensity of these peaks decreases with the increasing radiation dose. Findings The gamma-ray absorbed dose for these dosimeters was found to be up to 2 kGy for the solution samples and 40 Gy for the gels. Radiation chemical yield, dose response function, radiation sensitivity and before and after-irradiation stability under various conditions were discussed and studied. Practical implications It is expected that the radiolysis of the Mx dye can be used as radiation dosimeters in two different dosimetry systems; liquid and gel dosimeters. This can be applied in a wide range of gamma radiation practical industrial applications in water treatment, food irradiation dosimeters, radiotherapy and fresh food irradiation and seed production. Originality/value Both of the prepared Mx dyes, either as solutions or gel samples, can be facilely prepared from commercially, cheap, safe, available chemicals and suitable for useful applied Mx solutions and gels radiation dosimeters.

Download Full-text

Development of two dosimetry systems based on basic violet dye for possible use as radiation dosimeters

Pigment & Resin Technology ◽

10.1108/prt-11-2020-0118 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Nehad Magdy ◽

Sameh Gafar

Keyword(s):

Gamma Ray ◽

Raw Materials ◽

Absorbed Dose ◽

Chemical Yield ◽

Radiation Sensitivity ◽

Vital Role ◽

Radiation Chemical ◽

Content Type ◽

Before And After

Purpose The purpose of this research paper is to study a comparison between two dosimetry systems, both of them based on basic violet dye (BV). Design/methodology/approach The first system depends on (BV) (incorporating polyvinyl alcohol) as a thin-film dosimeter. The second system also relies on (BV) as a solution dosimeter, which is more sensitive to gamma rays. The two prepared film/solutions have a considerable signal that decreases upon irradiation and the strength of the signal decreases with increasing radiation dose. Findings The gamma ray absorbed dose for these dosimeters was found to be up to 35 kGy for films and 1 kGy for the liquid phase. All dosimetric characteristics as radiation chemical yield, additive substance, dose-response function, radiation sensitivity, also before and after-irradiation stability under various conditions were considered. Practical implications It is expected the vital role of gamma radiation on this dye in its two forms or two media. This reveals their wide applications in the field of gamma irradiation processing. Originality/value These two dosimetry systems which depend upon the same dye are safe to handle, inexpensive, available raw materials and can be applied in various dosimetry applications as mentioned above.

Download Full-text

Degradation of Acetaminophen in Aqueous Media by H2O2 Assisted Gamma Irradiation Process

Zeitschrift für Physikalische Chemie ◽

10.1515/zpch-2017-1071 ◽

2018 ◽

Vol 0 (0) ◽

Author(s):

Murtaza Sayed ◽

Fazal Hadi ◽

Javed Ali Khan ◽

Noor S. Shah ◽

Luqman Ali Shah ◽

...

Keyword(s):

Aqueous Media ◽

Absorbed Dose ◽

Degradation Process ◽

Chemical Yield ◽

Spectrophotometric Analysis ◽

Γ Irradiation ◽

Solution Ph ◽

Radiation Chemical ◽

G Value

Abstract In the present study, degradation of acetaminophen (ACT) aqueous solution was investigated up to an absorbed γ-irradiation dose of 1000 Gy. The effects of various additives on the degradation efficiency of ACT were also studied. The results showed that ACT degradation was increased with the increase of an absorbed dose. Based on spectrophotometric analysis, 82.5% degradation of the initial ACT concentration (9.98×10−5 M) was easily achieved at an absorbed dose of 1000 Gy. The decay of ACT followed pseudo-first order reaction kinetics at different initial concentrations. The radiation chemical yield (G-value) decreased with the increase of an absorbed dose, however at a specific absorbed dose G-values increased with the increase of ACT initial concentration. The addition of H2O2 in the range of 0.1–0.7% was effective for degradation of ACT. The degradation of ACT was inhibited in both acidic and basic solutions while maximium degradation effiency was acheived at nearly neautral solution pH, 7.6. The degradation process was markedly enhanced under oxidative conditions while strongly restrained under reductive conditions, which suggests the key role of oxidative radicals (˙OH) in the degradation of ACT.

Download Full-text

Determination of track registration efficiency and radiation chemical yield for loss of ester bonds due to gamma rays in Cellulose Acetate Butyrate (CAB) nuclear track detector

Journal of Radioanalytical and Nuclear Chemistry ◽

10.1007/s10967-010-0634-1 ◽

2010 ◽

Vol 286 (1) ◽

pp. 181-183 ◽

Cited By ~ 1

Author(s):

Vivek Chavan ◽

P. C. Kalsi ◽

V. S. Nadkarni ◽

A. K. Pandey

Keyword(s):

Cellulose Acetate ◽

Gamma Rays ◽

Chemical Yield ◽

Track Detector ◽

Radiation Chemical Yield ◽

Nuclear Track Detector ◽

Radiation Chemical ◽

Acetate Butyrate ◽

Registration Efficiency

Download Full-text

The influence of polymer concentration on the radiation-chemical yield of intermolecular crosslinking of poly(vinyl alcohol) by γ-rays in deoxygenated aqueous solution

Radiation Physics and Chemistry ◽

10.1016/s0969-806x(00)00188-2 ◽

2000 ◽

Vol 59 (1) ◽

pp. 91-95 ◽

Cited By ~ 23

Author(s):

Benlian Wang ◽

Sukekuni Mukataka ◽

Etsuo Kokufuta ◽

Makoto Kodama

Keyword(s):

Aqueous Solution ◽

Vinyl Alcohol ◽

Polymer Concentration ◽

Chemical Yield ◽

Poly Vinyl Alcohol ◽

Radiation Chemical Yield ◽

Radiation Chemical ◽

Γ Rays ◽

Intermolecular Crosslinking

Download Full-text

Development of two dosimeters for industrial use with low doses

Nuclear Technology and Radiation Protection ◽

10.2298/ntrp1702148e ◽

2017 ◽

Vol 32 (2) ◽

pp. 148-154 ◽

Cited By ~ 5

Author(s):

Moshira El-Kelany ◽

Sameh Gafar

Keyword(s):

Thin Film ◽

Gamma Ray ◽

Absorbed Dose ◽

Chemical Yield ◽

Radiation Sensitivity ◽

Liquid Form ◽

Radiation Chemical ◽

Before And After ◽

Industrial Use ◽

Dose Response Function

The present study involves a comparison between two dosimetry systems. The first system depends on victoria blue B (incorporating polyvinyl alcohol) as a thin-film dosimeter. The second system depends on the same dye as a liquid dosimeter, which is more sensitive to gamma rays. The prepared film/liquid has a considerable signal that increases upon irradiation and the intensity of the signal decrease with increasing radiation dose. The gamma ray absorbed dose for these dosimeters was found to be up to 25 kGy for the thin film and 700 Gy for the liquid form. Radiation chemical yield, additive substance, dose response function, radiation sensitivity, also before and after-irradiation stability under various conditions were discussed and studied.

Download Full-text

Bioactive potential of natural biomaterials: identification, retention and assessment of biological properties

Signal Transduction and Targeted Therapy ◽

10.1038/s41392-021-00512-8 ◽

2021 ◽

Vol 6 (1) ◽

Author(s):

Kieran Joyce ◽

Georgina Targa Fabra ◽

Yagmur Bozkurt ◽

Abhay Pandit

Keyword(s):

Tissue Engineering ◽

Therapeutic Potential ◽

Biological Properties ◽

Biological Assessment ◽

Cross Linking ◽

Natural Polymers ◽

Drug Delivery Device ◽

Biomedical Device ◽

Wide Range ◽

Bioactive Potential

AbstractBiomaterials have had an increasingly important role in recent decades, in biomedical device design and the development of tissue engineering solutions for cell delivery, drug delivery, device integration, tissue replacement, and more. There is an increasing trend in tissue engineering to use natural substrates, such as macromolecules native to plants and animals to improve the biocompatibility and biodegradability of delivered materials. At the same time, these materials have favourable mechanical properties and often considered to be biologically inert. More importantly, these macromolecules possess innate functions and properties due to their unique chemical composition and structure, which increase their bioactivity and therapeutic potential in a wide range of applications. While much focus has been on integrating these materials into these devices via a spectrum of cross-linking mechanisms, little attention is drawn to residual bioactivity that is often hampered during isolation, purification, and production processes. Herein, we discuss methods of initial material characterisation to determine innate bioactivity, means of material processing including cross-linking, decellularisation, and purification techniques and finally, a biological assessment of retained bioactivity of a final product. This review aims to address considerations for biomaterials design from natural polymers, through the optimisation and preservation of bioactive components that maximise the inherent bioactive potency of the substrate to promote tissue regeneration.

Download Full-text

Bioprinting Via a Dual-Gel Bioink Based on Poly(Vinyl Alcohol) and Solubilized Extracellular Matrix towards Cartilage Engineering

International Journal of Molecular Sciences ◽

10.3390/ijms22083901 ◽

2021 ◽

Vol 22 (8) ◽

pp. 3901

Author(s):

Mohsen Setayeshmehr ◽

Shahzad Hafeez ◽

Clemens van Blitterswijk ◽

Lorenzo Moroni ◽

Carlos Mota ◽

...

Keyword(s):

Extracellular Matrix ◽

Cell Viability ◽

Vinyl Alcohol ◽

Compression Modulus ◽

Synthetic Polymers ◽

Poly Vinyl Alcohol ◽

Cross Linking ◽

Light Curing ◽

Shape Retention ◽

Amine Groups

Various hydrogel systems have been developed as biomaterial inks for bioprinting, including natural and synthetic polymers. However, the available biomaterial inks, which allow printability, cell viability, and user-defined customization, remains limited. Incorporation of biological extracellular matrix materials into tunable synthetic polymers can merge the benefits of both systems towards versatile materials for biofabrication. The aim of this study was to develop novel, cell compatible dual-component biomaterial inks and bioinks based on poly(vinyl alcohol) (PVA) and solubilized decellularized cartilage matrix (SDCM) hydrogels that can be utilized for cartilage bioprinting. In a first approach, PVA was modified with amine groups (PVA-A), and mixed with SDCM. The printability of the PVA-A/SDCM formulations cross-linked by genipin was evaluated. On the second approach, the PVA was functionalized with cis-5-norbornene-endo-2,3-dicarboxylic anhydride (PVA-Nb) to allow an ultrafast light-curing thiol-ene cross-linking. Comprehensive experiments were conducted to evaluate the influence of the SDCM ratio in mechanical properties, water uptake, swelling, cell viability, and printability of the PVA-based formulations. The studies performed with the PVA-A/SDCM formulations cross-linked by genipin showed printability, but poor shape retention due to slow cross-linking kinetics. On the other hand, the PVA-Nb/SDCM showed good printability. The results showed that incorporation of SDCM into PVA-Nb reduces the compression modulus, enhance cell viability, and bioprintability and modulate the swelling ratio of the resulted hydrogels. Results indicated that PVA-Nb hydrogels containing SDCM could be considered as versatile bioinks for cartilage bioprinting.

Download Full-text