Novel Zwitterionic Copolymers to Enhance Hydrophilicity of PVDF Membranes: A Comprehensive Computational Study

Membrane technology covers all the engineering approaches with a key growth for large-scale industrial applications, including biotechnology, biomedical applications, food industry, and water and wastewater treatment. Poly (vinylidene fluoride) (PVDF) membrane has been gained remarkable attentions in recent years due to its excellent advantages in terms of thermal stability, chemical resistance, and high mechanical strength for water treatment. Despite its outstanding advantages, the performances of PVDF membranes are substantially limited by fouling problems. In this research study, we designed novel zwitterionic (ZW)-PVDF membranes with high hydrophilicity by employing a set of comprehensive computational methods. To achieve our goal, we first investigated the interactions occurring between water molecules and the fragments of hydrophobic and hydrophilic membrane models at the molecular level using the pair interaction energy decomposition analysis (PIEDA) as part of the fragment molecular orbital (FMO) method’s framework. This research direction is critical, since a research study of the reasons behind the interactions between water molecules and membrane materials would help design ground-breaking membranes with superior hydrophilicity. The computational studies and experimental analyses of PVDF and Polyacrylonitrile (PAN) membranes were considered as the models for hydrophobic and hydrophilic membranes, respectively. Density-functional theory (DFT), based on B3LYP functional and split-valance 6-311+G (d, p) basis sets, was used in order to optimize the geometry of PAN, PVDF, and their complexes with different numbers of water molecules. Furthermore, the functional groups of membrane surfaces were experimentally evaluated through Fourier-transform infrared spectroscopy (FTIR- ATR), 13C cross polarization magic angle spinning (13C CP MAS) Solid State Nuclear magnetic resonance SSNMR, and Fourier transform Raman (FT-Raman) spectroscopies. The confocal microscopic was also employed to interrogate water transport and the interactions between fluorescence particles through the membrane matrices. The non-covalent interactions in terms of electrostatic, exchange-repulsion, and charge-transfer parameters were comprehensively investigated for the designed ZW-PVDF copolymers. The performance of ZW moieties was derived from three different anionic groups in the ZW head, specifically, carboxylate, sulfonate, and phosphate. This approach was used in addition to the inclusion of a linker between the ZW head and the PVDF backbone, such as trimethyl ammonium groups and hydroxyl group, for an improvement of PVDF hydrophilicity. The quantum chemical calculations were conducted to examine the hydration structure of moieties. The interactions between the ZW moieties, with water molecules confirmed that it depended on the charged groups in addition to the chemical functional groups between charged groups. Furthermore, the types of anionic groups, the polar functional groups between charged groups, and the hydrophilic group, as a linker between charged groups of the ZW to the PVDF polymer backbone are the key reason for membrane hydrophilicity and the membrane water uptake. The double Zwitterionic PMAL®-C8-CB-OH-SB-PVDF was designed through the addition of protonated carboxyl group on a backbone of copolymer PMAL®-C8, and the protonated nitrogen atom of the amide group. This double zwitterion showed strong electrostatic interactions between individual water molecules and the secondary ammonium and the Oxygen of carboxybetaine, compared to PMAL®-C8-OH-SB-PVDF model. Our designed hydrophilic ZW-PVDF membranes, and especially the double zwitterion membrane, are an exciting development that can be applied in a broad range of water applications

Zeolites-Mixed-Matrix Nanofiltration Membranes for the Next Generation of Water Purification

Designing high performance and antifouling membranes are in a great need to remove water contaminations and to regulate the quality of drinking water. Mixed-matrix membranes (MMMs) could offer a solution to the permeability and selectivity trade-off in nanofiltration (NF) membranes. MMM could offer the physicochemical stability of a ceramic material while ensuring the desired morphology with higher nanofiltration permeability, selectivity, hydrophilicity, fouling resistance, as well as greater thermal, mechanical, and chemical strength over a wider temperature and pH range. Zeolites are fascinating and versatile materials, vital for a wide range of industries due to their unique structure, greater mechanical strength, and chemical properties. This chapter focused on zeolite-MMM for nanofiltration. Several key rules in the synthesis procedures have been comprehensively discussed for the optimum interfacial morphology between the zeolites and polymers. Furthermore, the influence of the zeolite filler incorporation has been discussed and explored for water purification. This chapter provided a broad overview of the MMM’s challenges and future improvement investigative directions

Zeolite Mixed Matrix Membranes (Zeolite-MMMs) for Sustainable Engineering

Mixed matrix membranes (MMMs) could provide a solution to the permeability and selectivity trade-off in polymeric membranes and bridge the gap with inorganic membranes. MMM could offer the physicochemical stability of a ceramic material while ensuring the desired morphology with higher permeability, selectivity, hydrophilicity, fouling resistance, as well as greater thermal, mechanical, and chemical strength over a wider temperature and pH range. Zeolites are fascinating and versatile materials, vital for a wide range of industries due to their unique structure, greater mechanical strength, and chemical properties. This chapter focused on zeolite-MMM and characterized various zeolite-reinforced polymeric membrane types and applications. Several key rules in the synthesis procedures have been comprehensively discussed for the optimum interfacial morphology between the zeolites and polymers. Furthermore, the influence of the zeolite filler incorporation has been discussed and explored for a range of applications. This chapter provided a broad overview of the MMM’s challenges and future improvement investigative directions

Comparing Four Methods for Preparing the Capillary Blood Sampling Site

Background: Capillary blood glucose measurement is one of the most important diagnostic procedures in managing and treating patients, especially those with diabetes. Since the preparation method of the capillary sampling site affects the blood glucose (BG) level, it is essential to identify the best preparation method with the least error estimation. This study compares the capillary BG level with the venous BG level after preparing the sampling site with four different preparation methods.  Methods: This quasi-experimental study has a single-group design. It was conducted on 85 nursing and midwifery students of Kashan University of Medical Sciences and Health Services, in 2022. The subjects who met the inclusion criteria were selected using convenience sampling. Capillary BG was measured from each finger using a glucometer while each finger was prepared with alcohol, water, soap and water, or no washing. Then, the venous blood sample of the same person was sent to the laboratory. The data were analyzed by SPSS software, version 22. The Friedman and Dunn post hoc tests were used to compare venous and capillary BG levels obtained using different methods. The significance level was set at P<0.05. Results: There were significant differences between venous BG levels and capillary BG levels in blood sampling site preparation with alcohol (P<0.05). Preparation with alcohol had the highest (7.34±27.03), and the soap and water had the lowest (-0.67±14.82) estimation errors.  Conclusion: The use of alcohol to prepare the blood sampling site, which is a common practice in many healthcare facilities, may misrepresent BG levels and lead to misdiagnosis and treatment. Therefore, it is suggested that the soap and water cleaning method be used instead, which has the lowest error compared to venous BG

Formylation of phenols using formamidine acetate

We report a new method to formylate phenol derivatives using formamidine acetate and acetic anhydride. This general-purpose transformation is a significant improvement over many other methods and does not require high temperatures or the addition of strong acid or base. Mono-, di-, and tri-formylated product can be obtained, depending on the substrate and conditions used

Risk factors for in-hospital mortality among patients with coronavirus-19 in Isfahan City, Iran

Background: The aim of the study is to explore the risk factors of mortality for hospitalized patients in three designated hospitals in Isfahan province.Materials and Methods: This retrospective cohort study was conducted on all positive coronavirus disease (COVID)-19 patients admitted to Khorshid, Isabn Maryam, and Amin hospitals in Isfahan province. The demographic, clinical, laboratory, and outcome data of patients who were died or discharged from February 24, 2020, to April 18, 2020, were extracted from patient's medical records.Results: Overall 1044 COVID-19 patients were included in this analysis. Based on the findings of this study, older age (& GE;65 years) (adjusted hazard ratio [aHR]: 2.06; 95% confidence interval [CI]: 1.13-3.76), chronic obstructive pulmonary disease (COPD) history (aHR: 2.52; 95% CI: 1.09-5.83), white blood cell (WBC) counts more than 10 x 103/L (aHR: 3.05; 95% CI: 1.42-6.55), Hb level < 13 gr/L (aHR: 2.82; 95% CI: 1.34-5.93), bilateral pulmonary infiltrates (aHR: 2.02; 95% CI: 1.12-3.64) at admission, development of acute respiratory distress syndrome (ARDS) (aHR: 1.87; 95% CI: 1.01-3.47), and intensive care unit (ICU) admission (aHR: 2.09; 95% CI: 1.04-4.18) during hospitalization were risk factors for in-hospital mortality in patients with COVID-19.Conclusions: Multiple factors were found related to the severity and death among COVID-19 patients. We were found that older age (& GE;65 years) with COPD history, high level of WBC, low level of Hb (< 13 g/L), bilateral pulmonary infiltrates at admission, development of ARDS, and ICU admission during hospitalization were identified as risk factors of death among COVID-19 patients. More related studies are needed in the futur

First report on self-rated health in a nationally-representative sample of Iranian adolescents: the Caspian-iii study

Objective: To evaluate predictive factors of adolescents′ appraisal of their health. Methods: The nationwide study, entitled "Childhood and Adolescence Surveillance and Prevention of Adult Non-communicable Diseases (CASPIAN) study," was conducted in 2010 among Iranian school students, aged 10-18. In addition to demographic factors and physical examination, variables as family structure, nutrition habits, physical activity, smoking, hygienic habits, violence, school attachment, family smoking, and family history of chronic diseases were assessed. The dependent variable is the self-rated health (SRH) and it was measured by 12 items, which had already been combined through latent class analysis. We had taken a dichotomous variable, i.e. the higher values indicate better SRH. The dependent variable was regressed on all predictors by generalized additive models. Results: 75% of adolescents had a good SRH. The linear and smooth effects of independent variables on SRH were observed. Among all the variables, physical activity had a positive linear effect on SRH (β = 0.08, P value = 0.003). Smoking, violence, and family history of disease associated to SRH non-linearly (P value < 0.05). Family smoking (β = -0.01) and hygienic habits (β = 0.27) related to SRH both linearly and non-linearly. Conclusions: Physical health and high risk behavior, either of linear or non-linear effect, are factors, which seem to shape the adolescents′ perception of health