Nanoparticles in Cancer Diagnosis and Treatment.

The use of tailored medication delivery in cancer treatment has the potential to increase efficacy while decreasing unfavourable side effects. For researchers looking to improve clinical outcomes, chemotherapy for cancer continues to be the most challenging topic. Cancer is one of the worst illnesses despite the limits of current cancer therapies. New anticancer medications are therefore required to treat cancer. Nanotechnology has revolutionized medical research with new and improved materials for biomedical applications, with a particular focus on therapy and diagnostics. In cancer research, the application of metal nanoparticles as substitute chemotherapy drugs is growing. Metals exhibit inherent or surface-induced anticancer properties, making metallic nanoparticles extremely useful. The development of metal nanoparticles is proceeding rapidly and in many directions, offering alternative therapeutic strategies and improving outcomes for many cancer treatments. This review aimed to present the most commonly used nanoparticles for cancer applications.

Application of plant products in the synthesis and functionalisation of biopolymers.

The burning of plastic trash contributes significantly to the problem of air pollution. Consequently, a wide variety of toxic gases get released into the atmosphere. It is of the utmost importance to develop biodegradable polymers that retain the same characteristics as those obtained from petroleum. In order to decrease the effect that these issues have on the world around us, we need to focus our attention on specific alternative sources capable of biodegrading in their natural environments. Biodegradable polymers have garnered much attention since they can break down through the processes carried out by living creatures. Biopolymers' applications are growing due to their non-toxic nature, biodegradability, biocompatibility, and environmental friendliness. In this regard, we examined numerous methods used to manufacture biopolymers and the critical components from which they get their functional properties. In recent years, economic and environmental concerns have reached a tipping point, increasing production based on sustainable biomaterials. This paper examines plant-based biopolymers as a good resource with potential applications in both biological and non-biological sectors. Scientists have devised various biopolymer synthesis and functionalization techniques to maximize its utility in various applications. In conclusion, recent developments in the functionalization of biopolymers through various plant products and their applications are discussed.

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.

Correction to: Release of an enantioselective nitrilase from Alcaligenes faecalis MTCC 126: a comparative study.

In the original version of our paper entitled "Release of an enantioselective nitrilase from Alcaligenes faecalis MTCC 126: a comparative study" (2005) 27:415-424, some references to already published articles were inadvertently left out.

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 (Z(p) > 0), according to a Hofmeister series (Cl(-) < Br(-) < NO(3)(-) < I(-) < SCN(-)), as well as at the isoionic point (Z(p) = 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.

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 (ζ) 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).

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 ion-surface dispersion interactions and ion hydration.

Enantioselective nitrilase from Pseudomonas putida: cloning, heterologous expression, and bioreactor studies.

Nitrilases have attracted tremendous attention for the preparation of optically pure carboxylic acids. This article aims to address the production and utilization of a highly enantioselective nitrilase from Pseudomonas putida MTCC 5110 for the hydrolysis of racemic mandelonitrile to (R)-mandelic acid. The nitrilase gene from P. putida was cloned in pET 21b(+) and over-expressed as histidine-tagged protein in Escherichia coli. The histidine-tagged enzyme was purified from crude cell extracts of IPTG-induced cells of E. coli BL21 (DE3). Inducer replacement studies led to the identification of lactose as a suitable and cheap alternative to the costly IPTG. Effects of medium components, various physico-chemical, and process parameters (pH, temperature, aeration, and agitation) for the production of nitrilase by engineered E. coli were optimized and scaled up to a laboratory scale bioreactor (6.6 l). Finally, the recombinant E. coli whole-cells were utilized for the production of (R)-(-)-mandelic acid.

Studies on the production of enantioselective nitrilase in a stirred tank bioreactor by Pseudomonas putida MTCC 5110.

Nitrilases constitute an important class of hydrolases, having numerous industrial applications. The present work aims to address the production of nitrile hydrolyzing enzymes from Pseudomonas putida MTCC 5110 in a 6l bioreactor. Effect of various physico-chemical conditions and process parameters like pH, temperature, aeration and agitation rates and inducer concentration was studied. Further, the enzyme activity was enhanced by adopting the inducer feeding strategy. Various biochemical engineering parameters pertaining to the cultivation of P. putida in different physico-chemical conditions were reported. Finally, segregation of growth phase from the enzyme production phase allowed significant reduction in total fermentation time.

Release of an enantioselective nitrilase from Alcaligenes faecalis MTCC 126: a comparative study.

Nitrilases constitute an important class of hydrolases, however, cheap and ready availability of enzyme sources limit their practical synthetic applications. The present investigation was directed to compare the applicability of various physical cell disintegration methods namely, solid shear, liquid shear and sonication, for the release of an enantioselective nitrilase from Alcaligenes faecalis MTCC 126. Different parameters associated with each method were optimized in order to ensure maximal release of active nitrilase. The methods were also compared under optimal conditions for their efficiency of nitrilase release and extent of cell disruption, and enzyme release were visualized under a differential interference contrast microscope (DIC) and SDS-PAGE, respectively. Maximum release of the enzyme protein from the cells was observed in case of liquid shear method employing high-pressure homogenization, however, the specific activity of nitrilase was highest in cell-free extract (CFE) generated by sonication. Both the solid shear and liquid shear proved to be equally effective for maximum release of intracellular enzymes, however, from the specific activity point of view, sonication was found to be a better one compared to other two methodologies. The generated cell-free extract can be further employed for the production of enantiopure chiral carboxylic acids, which are important chiral building blocks.