China
Africa
Explore chapters and articles related to this topic
Lutein: A Nutraceutical Nanoconjugate for Human Health
Published in Harishkumar Madhyastha, Durgesh Nandini Chauhan, Nanopharmaceuticals in Regenerative Medicine, 2022
Ishani Bhat, Bangera Sheshappa Mamatha
Lutein-loaded nanopolymersomes, similar to nanoliposomes, contain amphiphilic polymers as a substitute for phospholipid bilayers (Figure 11.3C). The self-assembly of polymersomes can be initiated by an injection method similar to liposomes to obtain an optimum particle size and entrapment efficiency. Self-assembled, lutein-loaded nanopolymersomes were designed using a polymer of octenyl succinic anhydride-modified short glucan chains (Chang et al. 2017). Despite the ultra-small size of 10–20 nm, the nanoconjugate was able to entrap 85% of lutein within the polymersome. Similarly, methoxypoly(ethylene glycol)-co-polyaspartic acid-imidazole and methoxy poly(ethylene glycol)-co-poly β-benzyl L-aspartate was used for such nanoconjugates (Zhang et al. 2018).
Mechanisms of Chemically Induced Glomerular Injury
Published in Robin S. Goldstein, Mechanisms of Injury in Renal Disease and Toxicity, 2020
Polyaspartic acid has been shown recently to protect rats from developing aminoglycoside nephrotoxicity.57,58 More studies are needed to define further the mechanism(s) which cause changes in glomerular structural and functional alterations after administration of aminoglycosides.
Agents for Microsphere Incorporation: Physicochemical Considerations and Physiological Consequences of Particle Embolization
Published in Neville Willmott, John Daly, Microspheres and Regional Cancer Therapy, 2020
It is instructive to compare the pattern of drug loading using albumin/polyaspartic acid as microsphere matrix (100% native drug) with systems using albumin alone as matrix material (15 to 50% native drug, remainder covalently bound). On the basis of this comparison it is proposed that all doxorubicin in protein microspheres is not in native form due to formation of a drug-protein conjugate with the bifunctional aldehyde, glutaraldehyde, linking amine groups of drug and protein (Figure 4A). In the presence of polyaspartic acid, the amine group of doxorubicin is not available for reaction with glutaraldehyde due to formation of an ionic complex with the polyanion (Figure 4B).
Studies of a novel bone-targeted nano drug delivery system with a HAP core-PSI coating structure for tanshinol injection
Published in Journal of Drug Targeting, 2023
Fengbo Yu, Hongyuan Wang, Qiang Wang, Fengguo Zhai, Jinghua Wang, Chunming Huang, Liao Cui
As Figure 1 shows, HAP is a major component of human teeth and bones. It is a weakly alkaline calcium phosphate salt with slightly soluble in water. The surface of HAP has a very high affinity and adherence for human tissues. HAP can gradually be dissolved by bodily fluids or absorbed by tissues, showing excellent biocompatibility, osteoconductivity, cell adhesion, biodegradability, and non-inflammatory properties [9,10]. Porous HAP is an efficient adsorbent, available as a carrier for nucleic acid and protein drugs [11,12]. According to the principles of green chemistry, polysuccinimide (PSI), a biodegradable, non-toxic, amorphous polymer, is created by direct condensation of aspartic acid monomers after dehydration [13]. PSI undergoes a ring-opening reaction with OH− in solution to produce polyaspartic acid (PAA), a water-soluble derivative with a protein-like structure that can be biodegraded in the presence of lysosomal enzymes in vivo [14]. The PSI derivatives can be achieved simply by mixing the PSI and amine-terminated compound in the solvent under a certain temperature and time without any catalyser. Additionally, PSI derivatives are green and potent inhibitors of the crystallisation of calcium salts in water [15,16]. Therefore, PSI and derivatives were selected as HAP coating materials.
Poly-γ-glutamic acid coating polymeric nanoparticles enhance renal drug distribution and cellular uptake for diabetic nephropathy therapy
Published in Journal of Drug Targeting, 2023
Qili Wang, Shunping Han, Yongqin Zhu, Guowei Wang, Danfei Chen
The cellular uptake efficiency was determined by flow cytometry after labelling the particles with a Cy5 fluorescence probe, as shown in Figure 3(B). Particle size and zeta potential are two key parameters affecting the cellular uptake profile of the particles [23]. To investigate the role of PGA coating in facilitating renal cellular uptake, L-polyaspartic acid (PAA)-coated nanoparticle (RAPP) was obtained concomitantly as the dummy nanoparticle with similar size and zeta potential as RGPP. Both RAPP and RGPP exhibited time-dependent cellular uptake profiles. The fluorescence intensity was increased when the incubation time was prolonged. Compared with RAPP, RGPP exhibited faster and efficient cellular uptake. After 0.5 h, 58% of RGPP was internalised into the HK-2 cells and its cellular uptake was then saturated at 1.5 h. In contrast, the internalisation of RAPP reached a plateau at 2.5 h. The higher cellular uptake efficiency of RGPP is possibly due to the enhanced affinity between PGA and GGT which are overexpressed on renal cells, such as HK-2 [24, 25].
Addressing the challenges to increase the efficiency of translating nanomedicine formulations to patients
Published in Expert Opinion on Drug Discovery, 2021
Sourav Bhattacharjee, David J. Brayden
Polymeric micelles have a hydrophobic core within a hydrophilic corona and offer loading possibilities for both hydrophilic and hydrophobic molecules. The polymeric constituent is usually a di-block or tri-block copolymer, where at least one of the blocks is hydrophilic and forms the outer layer. The hydrophobic block, on the other hand, forms the core, which in turn is stabilized by a range of hydrophobic and ionic bonds or complexation with metal ions. A wide range of polymeric blocks can be used to form cores with different hydrophilicity, such as polypropylene oxide (Pluronics®) [104], polyaspartic acid [105], polylactic acid [106], poly-ε-caprolactone (PCL) [107], and poly(β-benzyl-L-aspartate) [108]. Some of these polymers (e.g., PCL) are biodegradable and can be used to develop sustained-release formulations.