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Gene Therapy and Small Molecules Used in the Treatment of Cystic Fibrosis
Published in Yashwant Pathak, Gene Delivery, 2022
Manish P. Patel, Uma G. Daryai, Mansi N. Athalye, Praful D. Bharadia, Jayvadan Patel
A second method of non-viral gene delivery consists of complexes of DNA and cationic polymers that induce DNA condensation and a considerable size reduction of the complex within the plasma. Various cationic polymers have been used to form polyplexes with DNA, like histidylated polylysine, polylysine, polyethyleneimine, polyamidoamine dendrimer, chitosan, and polyallylamine (Montier et al., 2004). The high molecular weight, large extent of polymerization, and high degree of polydispersity of cationic polymers renders their characterization difficult (Midoux and Pichon, 2002). Therefore, low molecular weight cationic peptides have been also developed to provide controlled synthesis and defined purity of the polymers (Montier et al., 2004).
Nanomaterials for Theranostics: Recent Advances and Future Challenges *
Published in Valerio Voliani, Nanomaterials and Neoplasms, 2021
Eun-Kyung Lim, Taekhoon Kim, Soonmyung Paik, Seungjoo Haam, Yong-Min Huh, Kwangyeol Lee
Nanocarriers derived from both synthetic polymers, such as poly(lactic acid) (PLA) and poly(lactide-co-glycolide) (PLGA), and natural polymers, such as chitosan and collagen, have been extensively investigated for biomedical applications. Polymers encapsulate imaging or therapeutic payloads without modification or are conjugated covalently to the payloads. Amphiphilic block-co-polymers can be formulated into micelles with a hydrophobic core and a hydrophilic shell [569–575]. The hydrophobicity of the core can provide an ideal medium to contain highly hydrophobic drugs or imaging contrast agents such as QDs or magnetic nanoparticles. Polymer-based nanocarriers can be further surface modified with specific moieties for targeted delivery. Controlled release of encapsulated drugs from polymer-based nanocarriers is accomplished via degradation of the polymer under physiological conditions, drug diffusion through the polymer matrix, matrix swelling followed by drug diffusion, or structural change of polymer in response to the cell environment, e.g., pH [530, 591, 592]. However, the polydispersity of the molecular weight of the polymer leads to inherent inhomogeneity in the size of the polymer nanoparticles. This would potentially result in an unreliable drug-release profile, leading to reduced drug efficacy.
Starch-Based Nanocarriers of Nutraceuticals: Synthesis and Applications
Published in Raj K. Keservani, Anil K. Sharma, Rajesh K. Kesharwani, Nutraceuticals and Dietary Supplements, 2020
Alberto A. Escobar-Puentes, Adriana García-Gurrola, Fernando Martínez-Bustos
In another recent study, starch nanoparticles were evaluated as curcumin encapsulants. For this, starch was dissolved in water (5 mg/mL) and subjected to heating; afterward, an ethanolic solution with different concentrations of curcumin (1%–5%) was added to the solution of soluble starch previously mentioned to obtain charged nanocapsules. The size of nanoparticles was influenced by the introduction of curcumin molecules, resulting in sizes of 182, 203, 223, and 253 nm as the concentration of curcumin increased (1%, 2%, 3%, and 5%, respectively). However, the polydispersity indexes were lower than 0.2, indicating high homogeneity in all of the nanoparticulate systems. The 3% formulation of curcumin presented the highest encapsulation efficiency (97%) and antioxidant capacity; in addition, due to the high zeta potential value (−26) presented, it had the best colloidal stability for 30 days (Li et al., 2016).
Development of phospholipon®90H complex nanocarrier with enhanced oral bioavailability and anti-inflammatory potential of genistein
Published in Drug Delivery, 2023
Vaishnavi S. Shete, Darshan R. Telange, Nilesh M. Mahajan, Anil M. Pethe, Debarshi K. Mahapatra
Particle size and zeta potential are excellent indicators of nanoparticle physical stability. The evodiamine-phospholipid complex particle size of ∼246.1 nm significantly improved the drug sustained release and oral absorption efficiency (Zhang et al., 2012). The transport of bigger particles (larger than 5 mm) may include lymphatics, whereas the transport of smaller particles (less than 500 nm) may involve endocytosis (Lefevre et al., 1978; Savić et al., 2003). The particle size analysis of GPLC formulation (Figure 1a) revealed around ∼176.9 nm, with polydispersity indices of 0.28 (< 3) shows its suitable for oral drug delivery. The low polydispersity index indicates a limited particle size distribution range within complex formulations. Colloidal dispersion stability is evaluated by its zeta potential. Previous literature has suggested that a zeta potential value of ± 10 mV provides considerable stability to the system (Mazumder et al., 2016). The zeta potential for the GPLC formulation (Figure 1b) was found to be ∼− 6.78 mV, respectively. The obtained value appeared close to ∼− 10 mV, indicating the physical stability of GPLC formulations. The zeta potential value will vary depending on the kind and composition of phospholipids. The lower zeta potential of the complex can be explained by the contribution of Phospholipon®90H to the formation of negative charges in an aqueous environment with a neutral pH value. Therefore, good physical stability for GPLC formulations was suggested by reduced particle size, decreased polydispersity index, and modest zeta potential value.
Microneedle-assisted transdermal delivery of amlodipine besylate loaded nanoparticles
Published in Drug Development and Industrial Pharmacy, 2022
Ahlam Zaid Alkilani, Sukaina Nimrawi, Nusaiba K. Al-nemrawi, Jehad Nasereddin
The negative correlation between CS concentration and particle size suggests that the self-assembly of the nanoparticles is highly dependent on the extent of the saturation of the CS solution; CS molecules are more likely to drop out of the solution into smaller nanoparticles when the concentration of CS in the solution is sufficiently high. However, the negative correlation between particle size and polydispersity suggests that self-assembly at higher concentrations leads to erratic nanoparticle formation, ergo the higher variability in size evidenced by the increased polydispersity at smaller sizes. Increasing the concentration of NaTPP was found to result in larger nanoparticles that exhibit lower size variability (NaTPP concentration is positively correlated with particle size and negatively correlated with polydispersity). Further suggesting that increasing slower self-assembly from less concentrated CS solutions results in particles that are larger with lower size variability, likely due to the erratic self-assembly occurring at more saturated solutions. However, whether the observed effect can be attributable to the presence of NaTPP or due to the increased amount of deionized water added with the NaTPP solution should be further investigated, but is beyond the scope of this writing and is the subject of a future article.
The tiny big world of solid lipid nanoparticles and nanostructured lipid carriers: an updated review
Published in Journal of Microencapsulation, 2022
Heidi M. Abdel-Mageed, Amira E. Abd El Aziz, Saleh A. Mohamed, Nermeen Z. AbuelEzz
LNP are generally spherical consisting of at least one lipid bilayer which incorporates at least one internal aqueous core and can be subdivided based on their structure into liposomes, lipid nanoemulsions, solid lipid nanoparticles (SLN), and nanostructured lipid carriers (NLC). Recently, LNP has been utilised for targeted delivery using various routes of administration such as topical, oral, nasal, and pulmonary routes (Montoto et al.2020). Variation between lipids exists in structures and physicochemical properties as well as digestibility and absorption pathway. Hence, the selection of lipid composition and concentration has a remarkable effect on the biopharmaceutical profile of the drug molecule administered into the systemic circulation. Optimisation of formulation characteristics such as particle size, polydispersity index, zeta potential, drug release, and storage stability is essential for optimum therapeutic efficiency. Particle size and polydispersity index influence the dissolution rate of NP in biological fluids while zeta potential is crucial for the overall stability of the system (Montoto et al.2020, Abdel-Mageed et al.2021c). In addition, surface coating, passive and active targeting, stimuli-responsive, stealth, and smart LNP are all possible strategies to incorporate complex architectures, bio-responsive moieties, and targeting agents to enhance delivery and bioavailability (Abdel-Mageed et al.2021b).