Synthesis, Characterization, and Drug Delivery Application of Self-assembling Amphiphilic Cyclodextrin

Enhancing Systemic Translocation of Insecticides via Nanoformulations Incorporating β-Cyclodextrin Octadecarboxylate as a Carrier

The conversion of contact-killing pesticides into systemic pesticides can significantly enhance the bioavailability of pesticides, thereby reducing pesticide usage and environmental harm. A series of β-cyclodextrin fatty acid esters with varying branch chains were synthesized and employed as carriers in nanoformulation of insecticide. The investigation revealed that nanoformulations prepared using β-cyclodextrin octadecarboxylate (β-CDs) exhibited superior stability and remarkable systemic translocation within plants. Six contact-killing insecticide nanoformulations were developed utilizing β-CDs as carriers, and tests indicated that β-CDs significantly enhanced the systemic translocation of insecticides in plants compared to carrier-free nanoformulations. It was found that β-CDs increased the level of systemic translocation of insecticides by 5-12 times. Additionally, characterization results from λ-cyhalothrin-β-CDs nanoformulation demonstrated their superior ability to improve photolysis resistance, prolong release time, and extend insecticidal duration. Consequently, β-CDs can be utilized as a green additive in pesticide production to enhance the systemic translocation of pesticides in plants and increase their bioavailability.

A High-Performance Anti-Corrosive Epoxy Coating Based on Ultra-Thin Hydroxyapatite Nanosheets with pH-Responsive Functions

The changes in the working environment have necessitated greater requirements in terms of the long-term anti-corrosion ability of metal anti-corrosion coatings, and the emergence of intelligent coatings has met this demand. A nanocontainer with a hydrophobic inner cavity and hydrophilic outer cavity called β-cyclodextrin (β-CD) was grafted onto the surface of hydroxyapatite (HAp) with a silane coupling agent, encapsulating benzotriazole (BTA) and embedded in epoxy resin to improve the coating anticorrosion performance. The excellent corrosion resistance of the coating in immersion and scratch experiments was derived from the inert protective layer formed by the reaction of the rapidly released corrosion inhibitor with the corrosion products on the metal surface. After 30 days of immersion experiment, the coating could still maintain the low-frequency impedance value of 6.28 × 107 Ω cm2. In this work, the enhancement of the physical barrier function of HAp nanoparticle and the pH-response function conferred by β-cyclodextrin provided the coating with good passive and active acting abilities in corrosive environments, respectively.

In silico-assisted development of supersaturable preconcentrated isotropic mixture of atazanavir for augmenting biopharmaceutical performance in the presence of H2-receptor antagonist

The therapeutic potential of atazanavir (BCS Class II drug), a highly selective inhibitor of human immunodeficiency virus (HIV-1), has been largely limited due to its low intrinsic solubility at elevated pH resulting in low oral bioavailability. Thus, the current work describes the systematic development, optimization, and evaluation of hydroxypropyl methylcellulose acetate succinate (HPMC-AS)-based supersaturable preconcentrate isotropic mixture (SP-IM) containing long-chain triglyceride to improve intestinal lymphatic transport and augment oral bioavailability of atazanavir (ATZ). A D-optimal mixture design was employed for optimization of plain IM containing corn oil, oleic acid, Tween 80, and propylene glycol, evaluating various critical quality attributes (CQAs) like particle size, polydispersity index, self-emulsification time, % transmittance, and drug content. In silico analysis and in vitro supersaturation test facilitated the selection of HPMC-AS as a best suited polymeric precipitation inhibitor (PPI) for formulating ATZ loaded SP-IM (ATZ-SP-IM). In vitro dissolution data indicated that ATZ-SP-IM exhibits superior performance in 0.025 N HCl and pH 6.8 over pure drug. Ex vivo permeation and in vivo pharmacokinetic study of ATZ-SP-IM corroborated enhanced permeation (2.03 fold) and improved drug absorption via lymphatic transport in Wistar rats. Further, the pharmacokinetic performance of ATZ-SP-IM was not affected in presence of H₂ receptor antagonist. Therefore, the results showed that ATZ-SP-IM can significantly improve the biopharmaceutical attributes of ATZ so as to lay a foundation of further research on the new dosage form of ATZ.

Analysis of carbohydrates and glycoconjugates by matrix-assisted laser desorption/ionization mass spectrometry: An update for 2019-2020

This review is the tenth update of the original article published in 1999 on the application of matrix-assisted laser desorption/ionization (MALDI) mass spectrometry to the analysis of carbohydrates and glycoconjugates and brings coverage of the literature to the end of 2020. Also included are papers that describe methods appropriate to analysis by MALDI, such as sample preparation techniques, even though the ionization method is not MALDI. The review is basically divided into three sections: (1) general aspects such as theory of the MALDI process, matrices, derivatization, MALDI imaging, fragmentation, quantification and the use of arrays. (2) Applications to various structural types such as oligo- and polysaccharides, glycoproteins, glycolipids, glycosides and biopharmaceuticals, and (3) other areas such as medicine, industrial processes and glycan synthesis where MALDI is extensively used. Much of the material relating to applications is presented in tabular form. The reported work shows increasing use of incorporation of new techniques such as ion mobility and the enormous impact that MALDI imaging is having. MALDI, although invented nearly 40 years ago is still an ideal technique for carbohydrate analysis and advancements in the technique and range of applications show little sign of diminishing.

Application of molecular docking in elaborating molecular mechanisms and interactions of supramolecular cyclodextrin

The cyclodextrin (CD)-based supramolecular nanomedicines have attracted growing interest because of their superior characteristics, including desirable biocompatibility, low toxicity, unique molecular structure and easy functionalization. The smart structures of CD impart host-guest interaction for meeting the multifunctional needs of disease therapy. However, it faces challenges in formulation design and inclusion mechanism clarification of the functional supramolecular assemblies owing to the complicated structures and mechanisms. Fortunately, molecular docking helps the researchers to comprehend the interaction between the drug and the target molecule for achieving high-through screening from the database. In this review, we summarized the category and characteristics of molecular docking along with the properties and applications of CD. Significantly, we highlighted the application of molecular docking in elaborating molecular mechanisms and simulating complex structures at molecular levels. The issues and development of CD and molecular docking were also presented to provide beneficial reference and new insights for supramolecular nano-systems.

Cyclodextrin-Based Contrast Agents for Medical Imaging

Cyclodextrins (CDs) are naturally occurring cyclic oligosaccharides consisting of multiple glucose subunits. CDs are widely used in host–guest chemistry and biochemistry due to their structural advantages, biocompatibility, and ability to form inclusion complexes. Recently, CDs have become of high interest in the field of medical imaging as a potential scaffold for the development of a large variety of the contrast agents suitable for magnetic resonance imaging, ultrasound imaging, photoacoustic imaging, positron emission tomography, single photon emission computed tomography, and computed tomography. The aim of this review is to summarize and highlight the achievements in the field of cyclodextrin-based contrast agents for medical imaging.

Dexamethasone Sodium Phosphate Loaded Modified Cyclodextrin Based Nanoparticles: An Efficient Treatment for Rheumatoid Arthritis

The main aim of the current research was to develop a modified cyclodextrin based nanoparticulate drug delivery system to deliver dexamethasone sodium phosphate (DSP) for the treatment of rheumatoid arthritis (RA). DSP is a glucocorticoid (GC), and its limited application in RA therapy due to poor pharmacokinetics and its severe associated side effects. DSP loaded hydrophobically modified cyclodextrin based nanoparticles (DSP-NPs) prepared by a double emulsion solvent evaporation method. The nanoparticle size was <120 nm, good entrapment efficiency and excellent stability were obtained. TEM study showed that nanoparticles were perfectly spherical shape. The in-vitro drug release from nanoparticle follows the non-Fickian diffusion mechanism. The pharmacokinetic profile of DSP after encapsulation showing the 2.3-fold increase in AUC and extended mean residence time, which increases the chances of nanoparticles to extravasate into the site of inflammation by the EPR effect. The pharmacodynamic studies in the Adjuvant-induced Arthritis (AIA) rat model showing a significant reduction in arthritic score, paw thickness, and inflammatory cytokine level in serum. Adverse effects evaluation studies demonstrate a significant reduction in the associated undesirable effects on body weight, blood glucose level, renal impairment, and hematological abnormalities compared to marketed formulation. These results suggest that DSP-NPs can be used as an efficient therapy for RA.