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Fenugreek
Published in Dilip Ghosh, Prasad Thakurdesai, Fenugreek, 2022
Ujjwala Kandekar, Sunil Ramdasi, Prasad Thakurdesai
Aerogels are solids with lowermost density and very high porosities. The polysaccharide-based aerogels, called organic hydrogels, have a highly porous structure, high surface area, are biocompatible, and can be tuned for numerous pharmaceutical applications (Ulker and Erkey 2014).
Three-Dimensional Printing: Future of Pharmaceutical Industry
Published in Harishkumar Madhyastha, Durgesh Nandini Chauhan, Nanopharmaceuticals in Regenerative Medicine, 2022
Manju Bala, Anju Dhiman, Harish Dureja, Munish Garg, Pooja A Chawla, Viney Chawla
Clara Lopez-Iglesias prepared microparticles of alginate aerogel loaded with a bronchodialator, i.e., salbutamol sulphate by the thermal inkjet printing technique. The obtained narrow droplet size has the potential to treat acute asthma (Lopez-Iglesias et al. 2019).
Dentifrice Rheology
Published in Laba Dennis, Rheological Proper ties of Cosmetics and Toiletries, 2017
All type 1 dentifrice today contain “hydrated silica.” This is a term devised for the purpose of ingredient labeling. Unfortunately, it is a very broad in physical-chemical concept and encompasses vastly different physical forms of silicon dioxide with different physical properties. The “hydrated silicas” in use in marketed toothpastes range from xerogels to pyrogenic silicas. Xerogels approach classical dental abrasives in particle size and inertness, and lack of ability to form a strong three-dimensional network in a lean solvent system. Pyrogenic silicas are very effective at forming a network. Silica aerogels and some silica precipitates have particle size, surface area, and pore volumes intermediate between those of xerogels, on one hand, and the finer pyrogenic and fumed silicas, on the other, and can readily form three-dimensional networks with aqueous glycerine and sorbitol and other ingredients, e.g., PEGs. One precipitated silica preparation available for type 1 dentifrices is prepared in such fashion as to provide a reproducible distribution of abrasive particles and particles able to form a structured lean solvent system. It is most convenient, however, to discuss the toothpastes situation in terms of an essentially inactive abrasive particle (xerogel) and finer, structure-forming particles such as aerogels, fine precipitates, and pyrogenic silicas.
Risedronate-loaded aerogel scaffolds for bone regeneration
Published in Drug Delivery, 2023
Nahla El-Wakil, Rabab Kamel, Azza A. Mahmoud, Alain Dufresne, Ragab E. Abouzeid, Mahmoud T. Abo El-Fadl, Amr Maged
Amorphous cellulose (AmC), TEMPO-oxidized cellulose (NFC) and citric acid-cross-linked cellulose (NFC/AmC) nanofibers were prepared in this study. The properties of these nanofibers were examined using FTIR, X-ray diffractometry, and DSC. NFC and NFC/AmC showed dense and porous structures, while AmC showed an agglomerated, loose structure. The rigidity of NFC/AmC, due to its cross-linked structure, resulted in the formation of aerogel scaffolds with high brittleness and low compressibility compared to those prepared using NFC. All the fabricated aerogel scaffolds showed high porosity (above 90%). The addition of chitosan to NFC scaffolds slowed down the release of risedronate from them. The selected aerogel scaffolds prepared using NFC and chitosan were able to increase MG-63 cell proliferation and RUNX2 gene expression protein and, this effect increased when the scaffolds were loaded with risedronate. On the other hand, the presence of citric acid in chitosan-containing scaffolds decreased cell growth. These findings highlight the promising approach of using biopolymers produced from agro-wastes in pharmaceutical applications.
Pulmonary drug delivery with aerogels: engineering of alginate and alginate–hyaluronic acid microspheres
Published in Pharmaceutical Development and Technology, 2021
Tamara Athamneh, Adil Amin, Edit Benke, Rita Ambrus, Pavel Gurikov, Irina Smirnova, Claudia S. Leopold
Aerogels are materials which have attracted more and more attention from the scientific community because of their outstanding properties, such as a high surface area (500–1200 m2/g), an adjustable structure, a low thermal conductivity, a low dielectric constant (1–2), and a low index of refraction (∼1.05) (Carraher 2005; Schultz et al. 2005). Therefore, out of all known porous materials, aerogels find their major applications in the aerospace and building sectors (Baetens et al. 2011; Randall et al. 2011; Ochoa et al. 2012), in catalysis (Kistler et al. 1934; Swann et al. 1934), in chemical sensors (Plata et al. 2004), in energy storage devices (Long et al. 2008), as water repellent coatings, in acoustic, optical and gas cleaning (Gurav et al. 2010) and in drug delivery (García-González et al. 2011). Aerogels can be tailored in many forms for drug delivery purposes, such as monoliths, beads or microparticles by using different precursors, such as silica (Guenther et al. 2008), alginate (García-González et al. 2015), alginate–hyaluronic acid (Athamneh et al. 2019) and certain protein (Marin et al. 2014). Resulting from their low density (0.05–0.3 g/cm3), their high porosity (>90%) and consequently their outperforming air flowability, aerogel microparticles are considered an optimum candidate for pulmonary drug delivery if the particle size is appropriate.
Alginate-based aerogels as wound dressings for efficient bacterial capture and enhanced antibacterial photodynamic therapy
Published in Drug Delivery, 2022
Ning Guo, Yu Xia, Weishen Zeng, Jia Chen, Quanxin Wu, Yaxin Shi, Guoying Li, Zhuoyi Huang, Guanhai Wang, Yun Liu
Despite diverse materials used in wound dressings (Maleki et al., 2021; Liang et al., 2022), aerogels have been emergingly studied and demonstrated promising application prospect in hemostasis (Li et al., 2020a,b; Yao et al., 2022; Zheng et al., 2022). According to IUPAC (international union of pure and applied chemistry), aerogels are defined as gels comprised of microporous solid in which dispersed phase is gas. In another word, aerogels are a type of ultra-light materials with high porosity and large surface area. Actually, fluid absorption capacity is essential in the prevention of bleeding due to the huge amount of blood exudate (Yao et al., 2021). Owning to the high porosity of aerogels, the wound dressings are endowed with excellent blood exudate absorption ability. Compared to traditional wound dressings, aerogels-based wound dressings not only have blood exudate absorption ability but also possess a key capacity in maintaining the gaseous exchanges, which is also of importance for wound healing. In comparison with hydrogels, the highly porous network, adjustable surface properties, tunable pore sizes, low density and good biocompatibility of aerogels make them promising candidates for bactericidal applications (Zhang et al., 2020). Aerogels can achieve rapid capture and efficient elimination of bacteria to effectively treat bacterial wound infections due to its high porosity and large surface area (Kaya et al., 2021). Considering that ideal aerogels should be nontoxic, biocompatible and biodegradable, alginate is a good option and has been intensively researched for the fabrication of aerogels. As an anionic polysaccharide biopolymer isolated from brown algae, alginate illustrates negligible toxicity, low immunogenicity, excellent biocompatibility and biodegradability, which make it suitable for in vivo applications (Aderibigbe & Buyana, 2018; Ren et al., 2018; Varaprasad et al., 2020). Due to its gelling ability via Ca(II)-mediated ionotropic gelation under mild conditions, alginate allows the formation of hydrogels. Eventually, freeze-drying technology offers a green method for preparing alginate-based aerogels from wet gels to preserve the cross-linked 3D structures. Besides, the obtained aerogels achieve the continuous release of Ca(II) as a blood coagulation factor to accelerate hemostasis (Stenflo et al., 2000; Toyoda et al., 2018).