Iranian Journal of Polymer Science and Technology 10163255 36 6 2024 02 20 In situ gelling hydrogels based on biodegradable polymers for effective ocular drug delivery: A review In situ gelling hydrogels based on biodegradable polymers for effective ocular drug delivery: A review 575 604 2033 10.22063/jipst.2024.3487.2263 FA Golnaz Shajari Tabriz University Marziyeh Fathi Research Center for Pharmaceutical Nanotechnology, Tabriz University of Medical Sciences Hamid Erfan-Niya Department of Chemical and Petroleum Engineering, University of Tabriz Journal Article 2023 10 09 In the field of ophthalmology, despite the existence of various drugs for the treatment of ocular diseases, an appropriate drug delivery strategy has not been achieved yet due to the special physiology and anatomy of this organ. New ocular drug delivery systems (DDSs) have been designed to achieve long-term therapeutic levels. Hydrogels have been widely used in drug delivery systems due to their unique properties. In situ gelling hydrogels are one of the important materials used for ocular DDSs. The use of in situ hydrogels through site injection reduces the risk of complications associated with invasive surgical procedures, making it a safer option for ocular drug delivery. Also, in-situ gelling hydrogels have the ability to undergo phase transition in ocular tissues and change from liquid to viscoelastic gel state, and thus can prolong the shelf life of drugs and improve their bioavailability in ocular tissue. Polymers are the main raw materials for the preparation of in situ gelling hydrogels. Natural polymers have been widely studied and investigated in ocular DDS due to their biodegradability and biocompatibility. Polymers are the main raw materials for preparing in situ gelling hydrogels. Common natural polymers for hydrogel preparation include chitosan, starch, alginate, fibrin, collagen, gelatin, hyaluronic acid and dextran. This paper aims to review and discuss the recent development of in situ gelling hydrogels based on natural polymers as advanced ocular DDSs. This review also summarizes various in situ gelling ocular hydrogels responsive to different stimuli such as temperature, pH, and ion. Also to achieve a deeper understanding of in situ gelling hydrogels’ potential as new ocular treatment option, their biocompatibility and biodegradability will be discussed in ocular DDSs. Considering the special advantages of nanotechnology in DDSs, the combination of ophthalmic hydrogels with nanotechnology as well as available commercial hydrogels will be briefly discussed. In the field of ophthalmology, despite the existence of various drugs for the treatment of ocular diseases, an appropriate drug delivery strategy has not been achieved yet due to the special physiology and anatomy of this organ. New ocular drug delivery systems (DDSs) have been designed to achieve long-term therapeutic levels. Hydrogels have been widely used in drug delivery systems due to their unique properties. In situ gelling hydrogels are one of the important materials used for ocular DDSs. The use of in situ hydrogels through site injection reduces the risk of complications associated with invasive surgical procedures, making it a safer option for ocular drug delivery. Also, in-situ gelling hydrogels have the ability to undergo phase transition in ocular tissues and change from liquid to viscoelastic gel state, and thus can prolong the shelf life of drugs and improve their bioavailability in ocular tissue. Polymers are the main raw materials for the preparation of in situ gelling hydrogels. Natural polymers have been widely studied and investigated in ocular DDS due to their biodegradability and biocompatibility. Polymers are the main raw materials for preparing in situ gelling hydrogels. Common natural polymers for hydrogel preparation include chitosan, starch, alginate, fibrin, collagen, gelatin, hyaluronic acid and dextran. This paper aims to review and discuss the recent development of in situ gelling hydrogels based on natural polymers as advanced ocular DDSs. This review also summarizes various in situ gelling ocular hydrogels responsive to different stimuli such as temperature, pH, and ion. Also to achieve a deeper understanding of in situ gelling hydrogels’ potential as new ocular treatment option, their biocompatibility and biodegradability will be discussed in ocular DDSs. Considering the special advantages of nanotechnology in DDSs, the combination of ophthalmic hydrogels with nanotechnology as well as available commercial hydrogels will be briefly discussed.

http://jips.ippi.ac.ir/article_2033_59bd31b48272155f86ff9dd0aed23706.pdf

Iranian Journal of Polymer Science and Technology 10163255 36 6 2024 02 20 MXene-based membranes for water treatment: preparation, properties, and application MXene-based membranes for water treatment: preparation, properties, and application 605 625 2037 10.22063/jipst.2024.3527.2283 FA Samal Babanzadeh Iran Polymer and Petrochemical Institute 0000-0001-6368-6060 Journal Article 2023 11 21 The existence of life on Earth depends on the availability of water. Rapid population growth, industrial development, and shortage of freshwater resources have made human society face the global challenge of water shortage, and it is expected that the world's water demand will increase by 20-30% from now until 2040. To overcome this problem, different processes have been used to purify water, and among these processes, membrane separation can be a suitable technology to meet this challenge due to the high quality of produced water, simplicity of operation, ability to operate under mild conditions, and low energy consumption. The common technologies for water treatment like distillation require high energy consumption and these technologies can not meet the global demand for fresh water. Among the different membrane processes, reverse osmosis is an efficient technology to remove salt ions from brackish water to obtain potable water. In membrane separation methods, the selection of the appropriate material as a membrane is so important because the physical, chemical, and mechanical properties, and separation performance (water flux, selectivity and, salt rejection) of the membrane are strongly dependent on the selected material type. Hence, researchers are still interested in the use of new materials to improve membrane performance. MXene nanosheets (transition metal carbides and nitrides) are a new category of two-dimensional materials with graphene-like structures that have unique properties, including large surface area, narrow interlayer spacing, high hydrophilicity, and surface functionality, suitable physical, chemical, and mechanical properties for membrane applications. Mxene compounds are important both as new pure membrane structures and also as nanomaterials to improve the properties of polymers in membrane processes. To this end, in the present paper, comprehensive information has been introduced on MXene compounds, including their synthesis, surface functionality, and membrane fabrication, with a focus on water treatment technology. The existence of life on Earth depends on the availability of water. Rapid population growth, industrial development, and shortage of freshwater resources have made human society face the global challenge of water shortage, and it is expected that the world's water demand will increase by 20-30% from now until 2040. To overcome this problem, different processes have been used to purify water, and among these processes, membrane separation can be a suitable technology to meet this challenge due to the high quality of produced water, simplicity of operation, ability to operate under mild conditions, and low energy consumption. The common technologies for water treatment like distillation require high energy consumption and these technologies can not meet the global demand for fresh water. Among the different membrane processes, reverse osmosis is an efficient technology to remove salt ions from brackish water to obtain potable water. In membrane separation methods, the selection of the appropriate material as a membrane is so important because the physical, chemical, and mechanical properties, and separation performance (water flux, selectivity and, salt rejection) of the membrane are strongly dependent on the selected material type. Hence, researchers are still interested in the use of new materials to improve membrane performance. MXene nanosheets (transition metal carbides and nitrides) are a new category of two-dimensional materials with graphene-like structures that have unique properties, including large surface area, narrow interlayer spacing, high hydrophilicity, and surface functionality, suitable physical, chemical, and mechanical properties for membrane applications. Mxene compounds are important both as new pure membrane structures and also as nanomaterials to improve the properties of polymers in membrane processes. To this end, in the present paper, comprehensive information has been introduced on MXene compounds, including their synthesis, surface functionality, and membrane fabrication, with a focus on water treatment technology.

http://jips.ippi.ac.ir/article_2037_dbdf7c5a162eeddf65990f752e9fd1d7.pdf

Iranian Journal of Polymer Science and Technology 10163255 36 6 2024 02 20 A review on biopolymers for the application of new hemostatic materials in medicine A review on biopolymers for the application of new hemostatic materials in medicine 627 646 2034 10.22063/jipst.2024.3549.2287 FA Hassanzadeh-Tabrizi S.A. Advanced Materials Research Center, Department of Materials Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Iran. Journal Article 2023 12 18 Bleeding is one of the main causes of death in natural disasters as well as due to accidents and war injuries. The formation of stable blood clots or hemostasis is necessary to prevent blood loss and death from excessive bleeding. Although there is a process of self-coagulation in the body, but in severe injuries, this system cannot control the bleeding alone without the help of clotting agents. Traditional methods such as the use of sterile gauze and applying pressure in the bleeding area have been widely used to prevent bleeding. However, these methods are not very effective. Therefore, finding substances that can quickly prevent bleeding has been the subject of many studies. Meanwhile, various organic and inorganic materials have been taken into consideration. Some polymers have shown very promising results due to compatibility with body tissues as well as the ability to control and manipulate properties. Considering the importance of these polymers, in this research, an overview of these polymers is carried out and the mechanism of action of these polymers in controlling bleeding and blood coagulation will be investigated. Also, the latest strategies in design and activities on this subject will be discussed. Three mechanisms of blood thickening, activation of the coagulation cascade and creation of a physical barrier are the main factors of the performance of these substances. Starch polysaccharides, alginate and oxidized cellulose can be mentioned among the most famous biopolymers for hemostatic application. Also, collagen, gelatin, fibrin, thrombin and keratin poly peptides are used as other biopolymer sources in bleeding control. In the following, the strategies used in improving the properties of hemostatic polymer materials are reviewed. The research directions in this topic, which are of interest to researchers, will be discussed. Bleeding is one of the main causes of death in natural disasters as well as due to accidents and war injuries. The formation of stable blood clots or hemostasis is necessary to prevent blood loss and death from excessive bleeding. Although there is a process of self-coagulation in the body, but in severe injuries, this system cannot control the bleeding alone without the help of clotting agents. Traditional methods such as the use of sterile gauze and applying pressure in the bleeding area have been widely used to prevent bleeding. However, these methods are not very effective. Therefore, finding substances that can quickly prevent bleeding has been the subject of many studies. Meanwhile, various organic and inorganic materials have been taken into consideration. Some polymers have shown very promising results due to compatibility with body tissues as well as the ability to control and manipulate properties. Considering the importance of these polymers, in this research, an overview of these polymers is carried out and the mechanism of action of these polymers in controlling bleeding and blood coagulation will be investigated. Also, the latest strategies in design and activities on this subject will be discussed. Three mechanisms of blood thickening, activation of the coagulation cascade and creation of a physical barrier are the main factors of the performance of these substances. Starch polysaccharides, alginate and oxidized cellulose can be mentioned among the most famous biopolymers for hemostatic application. Also, collagen, gelatin, fibrin, thrombin and keratin poly peptides are used as other biopolymer sources in bleeding control. In the following, the strategies used in improving the properties of hemostatic polymer materials are reviewed. The research directions in this topic, which are of interest to researchers, will be discussed.

http://jips.ippi.ac.ir/article_2034_8076c5854f34492e4fb803c0a794b131.pdf

Iranian Journal of Polymer Science and Technology 10163255 36 6 2024 02 20 Studying the Physicochemical and Biological Properties of Hydrogels Based on Laponite and Modified Chitosan through the Substitution of the Amino Group Studying the Physicochemical and Biological Properties of Hydrogels Based on Laponite and Modified Chitosan through the Substitution of the Amino Group 647 667 2045 10.22063/jipst.2024.3550.2288 FA Maryam Nezadi Student, Amirkabir university https://orcid.org/0000-0001-7074-7415 Hamid Keshvari Amirkabir university Fatemeh Shokrolahi IPPI 0000-0003-3745-6231 Parvin Shokrollahi Assoc. prof., Iran Polymer and Petrochemical Institute Journal Article 2023 12 03 Hypothesis: This study was conducted with the aim of synthesizing and identifying an injectable hydrogel based on chitosan/laponite. First, water-soluble chitosan was obtained from the reaction of chitosan/glycidyl trimethylammonium chloride (GTMAC). Then, an injectable hydrogel was prepared from its combination with Laponite nanoparticles. Methods: Chitosan was reacted with GTMAC with ratios of 1:1, 3:1 and 6:1. Using FTIR and H1NMR, the successful synthesis of water-soluble chitosan was confirmed. Besides that; Thermal stability, solubility in water, ability to absorb and retain moisture, zeta potential, biocompatibility and antibacterial activity of modified samples were investigated and compared with pure chitosan. Then, the optimal sample of modified chitosan was combined with laponite at a ratio of 1:1, and the physicochemical, injectability, self-healing, rheological, and biocompatibility properties of this hydrogel were investigated. Findings: The substitution percentage of QCS1, QCS3 and QCS6 samples was above 25%, 50% and 74%, respectively. QCS3 and QCS6 samples showed better water solubility at different pHs. By increasing the percentage of substitution, the surface charge became more positive and the antibacterial activity was improved. However, the higher percentage of cell viability in the QCS3 sample makes it more suitable for biological applications. After hydrogel formation, the ionic and hydrogen interactions between the QCS/LAP in the hydrogel was confirmed by FTIR. Elemental analysis confirmed the uniform distribution of laponite in the hydrogel. SEM images showed a reduction in pore size after incorporating Laponite in the hydrogel. Rheological studies showed a 5-fold increase in the mixed shear modulus after the addition of laponite. Also, the gelation time of the hydrogel was calculated about 5 minutes. The percentage of cell viability obtained by the MTT test after 72 hours was 93%. Consequently, the introduced hybrid hydrogel can be a suitable choice for tissue engineering and drug delivery applications. Hypothesis: This study was conducted with the aim of synthesizing and identifying an injectable hydrogel based on chitosan/laponite. First, water-soluble chitosan was obtained from the reaction of chitosan/glycidyl trimethylammonium chloride (GTMAC). Then, an injectable hydrogel was prepared from its combination with Laponite nanoparticles. Methods: Chitosan was reacted with GTMAC with ratios of 1:1, 3:1 and 6:1. Using FTIR and H1NMR, the successful synthesis of water-soluble chitosan was confirmed. Besides that; Thermal stability, solubility in water, ability to absorb and retain moisture, zeta potential, biocompatibility and antibacterial activity of modified samples were investigated and compared with pure chitosan. Then, the optimal sample of modified chitosan was combined with laponite at a ratio of 1:1, and the physicochemical, injectability, self-healing, rheological, and biocompatibility properties of this hydrogel were investigated. Findings: The substitution percentage of QCS1, QCS3 and QCS6 samples was above 25%, 50% and 74%, respectively. QCS3 and QCS6 samples showed better water solubility at different pHs. By increasing the percentage of substitution, the surface charge became more positive and the antibacterial activity was improved. However, the higher percentage of cell viability in the QCS3 sample makes it more suitable for biological applications. After hydrogel formation, the ionic and hydrogen interactions between the QCS/LAP in the hydrogel was confirmed by FTIR. Elemental analysis confirmed the uniform distribution of laponite in the hydrogel. SEM images showed a reduction in pore size after incorporating Laponite in the hydrogel. Rheological studies showed a 5-fold increase in the mixed shear modulus after the addition of laponite. Also, the gelation time of the hydrogel was calculated about 5 minutes. The percentage of cell viability obtained by the MTT test after 72 hours was 93%. Consequently, the introduced hybrid hydrogel can be a suitable choice for tissue engineering and drug delivery applications.

http://jips.ippi.ac.ir/article_2045_19d03838779784ebfee663a797675502.pdf

Iranian Journal of Polymer Science and Technology 10163255 36 6 2024 02 20 Two-way facilitated transport membrane for CO2 separation with synergy of nucleophilic addition and π-complexing reactions: Molecular simulation and experimental study Two-way facilitated transport membrane for CO2 separation with synergy of nucleophilic addition and π-complexing reactions: Molecular simulation and experimental study 669 682 2039 10.22063/jipst.2024.3561.2295 FA Mahdi Elyasi Kojabad Faculty of Engineering, Behbahan Khatam Alanbia University of Technology, Behbahan, Iran Parya Amirabedi Faculty of Engineering, Behbahan Khatam Alanbia University of Technology, Behbahan, Iran Masoud Dorfeshan Faculty of Engineering, Behbahan Khatam Alanbia University of Technology, Behbahan, Iran Journal Article 2024 01 10 Hypothesis: PEBA, also known as polyether-block-amide, has emerged as a highly favorable polymer material for the production of CO2 separator membranes. The membranes made from PEBA rely on the solution-diffusion mechanism for separation. However, the trade-off limitation hinders the enhancement of both permeability and selectivity, posing a crucial challenge in the widespread adoption of these membranes in various industries. To address this issue, incorporating compounds that create facilitate transport mechanism into the separation process proves to be a viable solution. Methods: To address the trade-off limitation in polymer membranes, a novel two-way facilitated transfer membrane was developed in this research. This membrane consisted of a PEBA matrix with two different carriers. Aniline was selected for its nucleophilic addition reaction towards CO2, while alumina particles served as carriers for π-complexation reactions. The combination of these two carriers within the polymer matrix resulted in the establishment of a two-way facilitated transport mechanism. Findings: As a result of adding two types of carriers, aniline and alumina, to the PEBA matrix, the permeability of CO2 increased 4.2 times compared to the pure membrane, and the CO2/N2 selectivity also increased 2.1 times compared to the pure membrane, demonstrating the high potential of these two carriers in enhancing separation performance. Molecular simulation results showed that the increase in CO2 permeability was due to the increase in its diffusion coefficient within the membrane thickness, facilitated by the pathways created by alumina and aniline in the polymer matrix. Comparison of the permeability and selectivity of the membrane with other works on the Robeson curve showed that the resulting membrane was able to easily overcome the trade-off limitation, surpass the Robeson boundary, and transform into a membrane suitable for industrial applications in CO2 separation. Hypothesis: PEBA, also known as polyether-block-amide, has emerged as a highly favorable polymer material for the production of CO2 separator membranes. The membranes made from PEBA rely on the solution-diffusion mechanism for separation. However, the trade-off limitation hinders the enhancement of both permeability and selectivity, posing a crucial challenge in the widespread adoption of these membranes in various industries. To address this issue, incorporating compounds that create facilitate transport mechanism into the separation process proves to be a viable solution. Methods: To address the trade-off limitation in polymer membranes, a novel two-way facilitated transfer membrane was developed in this research. This membrane consisted of a PEBA matrix with two different carriers. Aniline was selected for its nucleophilic addition reaction towards CO2, while alumina particles served as carriers for π-complexation reactions. The combination of these two carriers within the polymer matrix resulted in the establishment of a two-way facilitated transport mechanism. Findings: As a result of adding two types of carriers, aniline and alumina, to the PEBA matrix, the permeability of CO2 increased 4.2 times compared to the pure membrane, and the CO2/N2 selectivity also increased 2.1 times compared to the pure membrane, demonstrating the high potential of these two carriers in enhancing separation performance. Molecular simulation results showed that the increase in CO2 permeability was due to the increase in its diffusion coefficient within the membrane thickness, facilitated by the pathways created by alumina and aniline in the polymer matrix. Comparison of the permeability and selectivity of the membrane with other works on the Robeson curve showed that the resulting membrane was able to easily overcome the trade-off limitation, surpass the Robeson boundary, and transform into a membrane suitable for industrial applications in CO2 separation.

http://jips.ippi.ac.ir/article_2039_8c1b98e2c2f8c752c915da57b0a18618.pdf

Iranian Journal of Polymer Science and Technology 10163255 36 6 2024 02 20 Investigating the influence of process parameters in digital light processing method on the fatigue behavior of acrylate dental materials Investigating the influence of process parameters in digital light processing method on the fatigue behavior of acrylate dental materials 683 694 2043 10.22063/jipst.2024.3603.2311 FA Mousa Vaezipour Technical and Vocational University Mohammad Reza Shabgard Department of Mechanical Engineering, University of Tabriz, Tabriz, Iran Mahdi Kazemi Isfahan university of technology Journal Article 2024 04 09 Hypothesis: The digital light processing (DLP) method is one of the additive manufacturing. Although the resins used in the DLP process are commonly used in clinical applications, some of them lack experiential information and related to mechanical properties, such as fatigue behavior. The focus of the present research is to examine the effect of process setting of the DLP method on the fatigue life of acrylic dental materials. It is expected that the setting parameters have a significant effect on the curing of the resin and as a result the mechanical properties, especially the fatigue behavior of the samples made of acrylate dental materials by the DLP process. Layer thickness, exposure time and light intensity are considered as input parameters of DLP process. Methods: A rotating bending fatigue test was conducted under a 0.6 bending stress and a frequency of 25 Hz. After that, to achieve the stress-life relationship, samples with longer and shorter fatigue life were placed in two different levels of fatigue stress (0.4 and 0.8 bending stress). In addition, analysis of variance (ANOVA) was used to examine the correlation between parameters and the effect coefficient of each parameter on the fatigue resistance of the printed samples. Findings: A direct correlation between resin curing and the fatigue life of the fabricated samples was observed. Insufficient resin curing or over-curing led to a decrease in fatigue resistance of the samples. The longest fatigue life was achieved for the sample fabricated with the following parameter settings: layer thickness: 25 µm, exposure time: 2.8 seconds, and light intensity: 160 W/m2, with a value of 86459 cycles. The minimum fatigue life for the sample fabricated with the parameter settings: layer thickness: 100 µm, exposure time: 2.8 seconds, and light intensity: 160 W/m2, was obtained with a value of 48569 cycles. Hypothesis: The digital light processing (DLP) method is one of the additive manufacturing. Although the resins used in the DLP process are commonly used in clinical applications, some of them lack experiential information and related to mechanical properties, such as fatigue behavior. The focus of the present research is to examine the effect of process setting of the DLP method on the fatigue life of acrylic dental materials. It is expected that the setting parameters have a significant effect on the curing of the resin and as a result the mechanical properties, especially the fatigue behavior of the samples made of acrylate dental materials by the DLP process. Layer thickness, exposure time and light intensity are considered as input parameters of DLP process. Methods: A rotating bending fatigue test was conducted under a 0.6 bending stress and a frequency of 25 Hz. After that, to achieve the stress-life relationship, samples with longer and shorter fatigue life were placed in two different levels of fatigue stress (0.4 and 0.8 bending stress). In addition, analysis of variance (ANOVA) was used to examine the correlation between parameters and the effect coefficient of each parameter on the fatigue resistance of the printed samples. Findings: A direct correlation between resin curing and the fatigue life of the fabricated samples was observed. Insufficient resin curing or over-curing led to a decrease in fatigue resistance of the samples. The longest fatigue life was achieved for the sample fabricated with the following parameter settings: layer thickness: 25 µm, exposure time: 2.8 seconds, and light intensity: 160 W/m2, with a value of 86459 cycles. The minimum fatigue life for the sample fabricated with the parameter settings: layer thickness: 100 µm, exposure time: 2.8 seconds, and light intensity: 160 W/m2, was obtained with a value of 48569 cycles.

http://jips.ippi.ac.ir/article_2043_95cbce8d86b1c5fdd6dcbc88711b837c.pdf