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The Impact of Carbon-Based Nanomaterials in Biological Systems
Published in Swamini Chopra, Kavita Pande, Vincent Shantha Kumar, Jitendra A. Sharma, Novel Applications of Carbon Based Nano-Materials, 2023
Leirika Ngangom, Kunal Sharma, Pankaj Bhatt, Nilay Singhand, Neha Pandey
In the present study, various reasons were laid down as to how CBNs have acquired great attention in the past years in biomedical applications, plant systems, and environmental applications. In the last two decades, researchers have put terrific efforts to understand CBNs which are one of the broadly used nanomaterials. The interesting fact about CBNs is the occurrence of both organic π-π stacking characteristics and inorganic semiconducting properties. Concurrently, it reacts to light and interacts with other biological molecules. Such features bring a huge advantage for the future. In terms of the toxic impact on the biological system, various chemical modification approaches are being drafted and effectively employed in biological applications, like cancer therapy, drug delivery, and recognition of biomolecules. The reviewed literature of CBNs has focused on a few advancements in environmental applications, biomedical applications, and green plants. Therefore, more scientific investigations are required to know thoroughly about the toxicity impact of CBNs on humans, animals, plants, and the environment.
Polysaccharides: An Overview
Published in Shakeel Ahmed, Aisverya Soundararajan, Pullulan, 2020
S. Vijayanand, Ashwini Ravi, Aisverya Soundararajan, Annu, P. N. Sudha, J. Hemapriya
Polysaccharides are the integral component of plant biomass, and 90% of the total polysaccharide produced on earth is constituted by vegetables. Apart from vegetables, they are produced by bacteria, fungi, algae, and animals [39, 99]. Different types of polysaccharides include starch, glycogen, cellulose, pectin, chitin, hemicellulose, lignin, etc [35]. Since ancient times, polysaccharides have been used in several industrial applications such as pharmaceuticals, food and nutrition, and other non-food industries. In the food industry, it has been used as emulsifiers, stabilizer, thickening agent, and as packaging materials [90, 104]. In addition to these, they play a vital role in the pharmaceutical industry due to their several advantageous characteristics such as biocompatibility, biodegradability, and ability of chemical modification [151]. They have been widely applied as binders, drug-release modifiers, thickeners, stabilizers, disintegrants, suspending agents, gelling agents, and as biodhesives [53]. Because of these wide ranges of applications, the market of polysaccharides market is continuously increasing. Therefore, it is essential to know the different types of polysaccharides produced by the biological entities. This chapter deals with the different types of natural polysaccharides and their applications in various fields.
Polysaccharides used in Nanoparticle based Drug Delivery Formulations
Published in Akhilesh Vikram Singh, Bang-Jing Li, Polysaccharides in Advanced Drug Delivery, 2020
Sreeranjini Pulakkat, Krishna Radhakrishnan
Polyethyleneglycol (PEG) has been employed extensively in biomedical research as a soluble polymeric modifier in organic synthesis owing to its outstanding physicochemical and biological properties such as high hydrophilicity, solubility, biocompatibility, biodegradability, ease of chemical modification and absence of antigenicity and immunogenicity. It enables prevention of bacterial surface growth, decrease of plasma protein binding and erythrocyte aggregation, and prevention of recognition by the immune system. Recently, PEG grafted chitosan and chitosan derivatives have been widely studied by many researchers[50]. Yoksan et al. grafted PEG-methyl ether onto N-Phthaloyl chitosan chains and obtained stable sphere-like nanoparticles with size as small as 80–100 nm by simply adjusting the hydrophobicity/hydrophilicity of the chitosan chain[51]. Whereas, Opanasopit et al. used N-phthaloyl chitosan-grafted PEG-methyl ether, to form spherical core–shell micelle-like nanoparticles exhibiting sizes in the range of 100–250 nm[52] Methoxy PEG-grafted-chitosan conjugates was used by Jeong et al.[53] and Yang et al.[54] to develop polymeric micelles and monodisperse self-aggregated nanoparticles respectively for drug delivery applications.
Design and evaluation of sustained release hydrophilic matrix tablets of Piroxicam based on carboxymethyl xanthan derivatives
Published in Soft Materials, 2021
Madiha M. Yahoum, Sonia Lefnaoui, Nadji Moulai-Mostefa
During recent years, XG has been intensively studied as a carrier for controlled drug release. It was specially used as the candidate matrix-forming or retardant material to obtain suitable slow release of drugs.[6,7] Thereby, XG was employed as a sustained-release excipient because of its swelling capacity.[8,9] Despite the fact that XG is an effective biopolymer that has been used in drug delivery, its ability to control the drug release is limited because of its low particle hydration characteristics. Thus, chemical modification provides an efficient route not only to remove such drawbacks but also to improve swelling and solubilization. Hence, the chemical modification aims to develop functional characteristics that make this material more useful in pharmaceutical applications.
Shielding effect of a PEG molecule of a mono-PEGylated peptide varies with PEG chain length
Published in Preparative Biochemistry and Biotechnology, 2018
Ngoc-Thanh Thi Nguyen, Soi Yun, Dong Woo Lim, E. K. Lee
Chemical modification of a peptide or protein with PEG (PEGylation) is an established approach to improve pharmacokinetic properties, the therapeutic index, and drug delivery characteristics by extending the systemic circulation half-life and reducing immunogenicity.[1,2] A PEGylation mixture usually contains several different species such as unreacted PEG, unreacted peptide/protein, isomeric mono-PEGylates, and multi-PEGylates, as well as the desired mono-PEGylate. To purify the desired PEGylate from the mixture, the differences of the molecular size, surface charge, hydrophobicity, shape, and solubility among the species are exploited[3,4] using techniques such as hydrophobic interaction chromatography, reverse phase chromatography, size exclusion chromatography, and ion exchange chromatography.[5–7] Among them, cation exchange (CEX) chromatography that exploits the modified electrostatic interaction property after PEGylation is the most widely used.
Chemical and biological immobilization mechanisms of potentially toxic elements in biochar-amended soils
Published in Critical Reviews in Environmental Science and Technology, 2020
Tharanga Bandara, Ashley Franks, Jianming Xu, Nanthi Bolan, Hailong Wang, Caixian Tang
Chemical modification involves acid/base treatment, organic solvent treatment, and coating with graphene/nanotube/metal oxides. In terms of PTE removal efficiency, chemically-modified biochars are more effective than physically-modified ones. The major disadvantages of chemical activation are high cost and risk of chemical changes in the soil matrix.