Biopolymer: A Sustainable Material for Food and Medical Applications

Biopolymers are a leading class of functional material suitable for high-value applications and are of great interest to researchers and professionals across various disciplines. Interdisciplinary research is important to understand the basic and applied aspects of biopolymers to address several complex problems associated with good health and well-being. To reduce the environmental impact and dependence on fossil fuels, a lot of effort has gone into replacing synthetic polymers with biodegradable materials, especially those derived from natural resources. In this regard, many types of natural or biopolymers have been developed to meet the needs of ever-expanding applications. These biopolymers are currently used in food applications and are expanding their use in the pharmaceutical and medical industries due to their unique properties. This review focuses on the various uses of biopolymers in the food and medical industry and provides a future outlook for the biopolymer industry.</jats:p

Biopolymer: a sustainable material for food and medical applications

Biopolymers are a leading class of functional material suitable for high-value applications and are of great interest to researchers and professionals across various disciplines. Interdisciplinary research is important to understand the basic and applied aspects of biopolymers to address several complex problems associated with good health and well-being. To reduce the environmental impact and dependence on fossil fuels, a lot of effort has gone into replacing synthetic polymers with biodegradable materials, especially those derived from natural resources. In this regard, many types of natural or biopolymers have been developed to meet the needs of ever-expanding applications. These biopolymers are currently used in food applications and are expanding their use in the pharmaceutical and medical industries due to their unique properties. This review focuses on the various uses of biopolymers in the food and medical industry and provides a future outlook for the biopolymer industry

Sustainability of food packaging

Food packaging preserves food safety and ensures food quality throughout the supply chain. Both can be achieved by the shielding function of the packaging against negative ambient influences such as mechanical damage, light, or water vapor. Material, form, and packaging concepts vary widely, which thus also differentiates the environmental impact of packaging. There is broad consent on the definition of sustainable packaging, which has to be effective, efficient, and safe for human health and the environment. Renewable sources have gained importance and biologically originated resources are one of the main alternatives for new applications in packaging. This chapter provides an overview of the sustainability of food packaging, the role of various biological/renewable materials in packaging, the current market scenario, and sustainable ecosystem management with the new adoption of advanced packaging materials. We provide an overview of sustainable food packaging advancements via life cycle assessment (LCA) to aid researchers and industries in working towards sustainable food packaging

Ion specific surface charge density of SBA-15 mesoporous Silica

Potentiometric titrations were used to estimate the surface charge density of SBA-15 mesoporous silica in different salt solutions. It was found that surface charge depends both on cation type, following a Hofmeister series (Cs+ <Guanidinium+<K+<Na +<Li+), and on salt concentration (in the range 0.05-1 M). The surface charge series is reproduced by theoretical calculations performed using a modified Poisson-Boltzmann equation that includes ionic dispersion forces with ab initio ion polarizabilities and hydrated ions. The hydration model assigns an explicit hydration shell to kosmotropic (strong hydrated) ions only. The Hofmeister series appears to be due to the combination of ionsurface dispersion interactions and ion hydration

Hofmeister challenges: Ion binding and charge of the BSA protein as explicit examples

Experiments on bovine serum albumin (BSA) via potentiometric titration (PT) and electrophoretic light scattering (ELS) are used to study specific-ion binding. The effect is appreciable at a physiological concentration of 0.1 M. We found that anions bind to the protein surface at an acidic pH, where the protein carries a positive charge (Zp > 0), according to a Hofmeister series (Cl- < Br- < NO3- < I- < SCN-), as well as at the isoionic point (Zp = 0). The results obtained require critical interpretation. The measurements performed depend on electrostatic theories that ignore the very specific effects they are supposed to reveal. Notwithstanding this difficulty, we can still infer that different 1:1 sodium salts affect the BSA surface charge/pH curve because anions bind to the BSA surface with an efficiency which follows a Hofmeister series

Ion Specific Surface Charge Density of SBA-15 Mesoporous Silica

Potentiometric titrations were used to estimate the surface charge density of SBA-15 mesoporous silica in differentsalt solutions. It was found that surface charge depends both on cation type, following a Hofmeister series (Csþ&lt;Guanidiniumþ&lt;Kþ&lt;Naþ&lt;Liþ), and on salt concentration (in the range 0.05-1 M). The surface charge series isreproduced by theoretical calculations performed using a modified Poisson-Boltzmann equation that includes ionicdispersion forces with ab initio ion polarizabilities and hydrated ions. The hydration model assigns an explicit hydrationshell to kosmotropic (strong hydrated) ions only. The Hofmeister series appears to be due to the combination of ionsurfacedispersion interactions and ion hydration.</p

Measurements and Theoretical Interpretation of Points of Zero Charge/Potential of BSA Protein

The points of zero charge/potential of proteins depend not only on pH but also on how they are measured. They depend also on background salt solution type and concentration. The protein isoelectric point (IEP) is determined by electrokinetical measurements, whereas the isoionic point (IIP) is determined by potentiometric titrations. Here we use potentiometric titration and zeta potential (Χ) measurements at different NaCl concentrations to study systematically the effect of ionic strength on the IEP and IIP of bovine serum albumin (BSA) aqueous solutions. It is found that high ionic strengths produce a shift of both points toward lower (IEP) and higher (IIP) pH values. This result was already reported more than 60 years ago. At that time, the only available theory was the purely electrostatic Debye-Hückel theory. It was not able to predict the opposite trends of IIP and IEP with ionic strength increase. Here, we extend that theory to admit both electrostatic and nonelectrostatic (NES) dispersion interactions. The use of a modified Poisson-Boltzmann equation for a simple model system (a charge regulated spherical colloidal particle in NaCl salt solutions), that includes these ion specific interactions, allows us to explain the opposite trends observed for isoelectric point (zero zeta potential) and isoionic point (zero protein charge) of BSA. At higher concentrations, an excess of the anion (with stronger NES interactions than the cation) is adsorbed at the surface due to an attractive ionic NES potential. This makes the potential relatively more negative. Consequently, the IEP is pushed toward lower pH. But the charge regulation condition means that the surface charge becomes relatively more positive as the surface potential becomes more negative. Consequently, the IIP (measuring charge) shifts toward higher pH as concentration increases, in the opposite direction from the IEP (measuring potential)