Preliminary investigation of novel tetra-tailed macrocycle amphiphile based nano-vesicles for amphotericin B improved oral pharmacokinetics

Synthesis of calix (4) resorcinarene based amphiphilic macrocycle as an efficient nanocarrier for Amphotericin-B to enhance its oral bioavailability

The supramolecular-based macrocyclic amphiphiles have fascinating attention and find extensive utilization in the pharmaceutical industry for efficient drug delivery. In this study, we designed and synthesized a new supramolecular amphiphilic macrocycle to serve as an efficient nanocarrier, achieved by treating 4-hydroxybenzaldehyde with 1-bromotetradecane. The derivatized product was subsequently treated with resorcinol to cyclize, resulting in the formation of a calix(4)-resorcinarene-based supramolecular amphiphilic macrocycle. The synthesized macrocycle and intermediate products were characterized using mass spectrometry, IR, and 1H NMR spectroscopic techniques. The amphotericin-B (Amph-B)-loaded and unloaded amphiphiles were screened for biocompatibility studies, vesicle formation, particle shape, size, surface charge, drug entrapment, in-vitro release profile, and stability through atomic force microscopy (AFM), Zetasizer, HPLC, and FT-IR. Amph-B -loaded macrocycle-based niosomal vesicles were investigated for in-vivo bioavailability in rabbits. The synthesized macrocycle exhibited no cytotoxicity against normal mouse fibroblast cells and was found to be hemocompatible and safe in mice following an acute toxicity study. The drug-loaded macrocycle-based vesicles appeared spherical, nano-sized, and homogeneous in size, with a notable negative surface charge. The vesicles remained stable after 30 days of storage. The results of Amph-B oral bioavailability and pharmacokinetics revealed that the newly tailored niosomal formulation enhanced drug solubility, protected drug degradation at gastric pH, facilitated sustained drug release at the specific target site, and delayed plasma drug clearance. Incorporating such advanced niosomal formulations in the field of drug delivery systems has the potential to revolutionize therapeutic outcomes and improve the quality of patient well-being.

The physicochemical properties and molecular docking study of plasticized amphotericin B loaded sodium alginate, carboxymethyl cellulose, and gelatin-based films

Plasticizers are employed to stabilize films by safeguarding their physical stability and avoiding the degradation of the loaded therapeutic drug during processing and storage. In the present study, the plasticizer effect (glycerol) was studied on bioadhesive films based on sodium alginate (SA), carboxymethyl cellulose (CMC) and gelatin (GE) polymers loaded with amphotericin B (AmB). The main objective of the current study was to assess the morphological, mechanical, thermal, optical, and barrier properties of the films as a function of glycerol (Gly) concentration (0.5-1.5 %) using different techniques such as Scanning Electron Microscope (SEM), Texture analyzer (TA), Differential Scanning Calorimeter (DSC), X-Ray Diffraction (XRD), and Fourier Transforms Infrared Spectroscopy (FTIR). The concentration increase of glycerol resulted in an increase in Water Vapor Permeability (WVP) (0.187-0.334), elongation at break (EAB) (0.88-35.48 %), thickness (0.032-0.065 mm) and moisture level (17.5-41.76 %) whereas opacity, tensile strength (TS) (16.81-0.86 MPa), and young's modulus (YM) (0.194-0.002 MPa) values decreased. Glycerol incorporation in the film-Forming solution decreased the brittleness and fragility of the films. Fourier Transform Infrared (FTIR) spectra showed that intermolecular hydrogen bonding occurred between glycerol and polymers in plasticized films compared to control films. Furthermore, molecular docking was applied to predict the binding interactions betweem AmB, CMC, gelatin, SA and glycerol, which further endorsed the stabilizing effects of glycerol in the complex formation between AmB, CMC, SA, and gelatin. The Findings of the current study demonstrated that this polymeric blend could be used to successfully prepare bioadhesive films with glycerol as a plasticizer.

Synthetic star shaped tetra-tailed biocompatible supramolecular amphiphile as an efficient nanocarrier for Amphotericin B

Macrocycle-based amphiphiles are capable of self-assembling into multidimensional nano-architecture with defined dimensions for various applications. Herein we report the synthesis, physio-chemical characterizations and oral drug delivery profiling of resorcinarene-based amphiphilic supramolecular macrocycle. The macrocycle was synthesized in two-step reaction and characterized using ¹H NMR, Mass spectrometry and IR spectroscopic techniques. The synthesized macrocycle was assessed for vesicles formation, checked for biocompatibility and then Amphotericin B (Amp-B) was entrapped in macrocycle-based vesicles. The drug loaded vesicles were characterized for shape, size, homogeneity, drug entrapment, surface charge, in-vitro release profile and stability. Amp-B loaded macrocycle based vesicles were examined in rabbits for in-vivo bioavailability and compared with plan drug suspension. The synthesized macrocycle was non-toxic in normal mouse fibroblast cells, compatible with blood and safe in mice. The drug loaded macrocycle based vesicles appeared spherical with 279.4 nm size and - 12.2 mV zeta potential loading 85.45 % drug. The drug loaded vesicles storage stability for 30 days and gastric fluid stability for 1 h were it retained nearly 90 % drug at 30th day and 83.79 % drug at 1 h in gastric fluid. Oral bioavailability of Amp-B in rabbits was markedly enhanced when delivered in synthesized macrocycle based vesicles in comparison with plan drug suspension. Results of this study indicate that the synthesized star shaped tetra-tailed supramolecular amphiphile could be used as an efficient nanocarrier for enhancing oral bioavailability of drugs with solubility and bioavailability issues like Amp-B.

Nanovesicles containing curcumin hold promise in the development of new formulations of anti-Acanthamoebic agents

In this study, curcumin-nanoformulations were tested for anti-Acanthamoebic properties. Curcumin-loaded nanovesicles were synthesized, followed by characterization with Fourier transform infrared spectroscopy, ultraviolet-visible spectrophotometry, and atomic force microscopy. Using amoebicidal assay, the effects of curcumin-nanoformulations were investigated against A. castellanii belonging to the T4 genotype. To determine the effects of curcumin-nanoformulations on host cells, cytotoxicity assays were performed using human keratinocyte cells (HaCat). The results revealed that nanovesicles formulation of curcumin enhanced the anti-Acanthamoebic effects of curcumin as compared with curcumin alone. The viability decreased with increasing concentration of curcumin and/or lipid-based carrier (Noisome) (FCBR18) in a dose-dependent manner. Curcumin and curcumin-loaded nanovesicles exhibited minimal cytotoxic effects against human cells in all tested concentrations. Both concentrations of FCBR18 proved effective in inhibiting amoebae excystation. In contrast, curcumin alone showed insignificant effects against amoebae excystation. Taken together, these findings clearly showed that curcumin-loaded nanovesicles show enhanced anti-Acanthamoebic efficacy without harming human cells, and these nanotherapeutics may hold promise in the development of new formulations of anti-Acanthamoebic agents.

Design of N-Methyl-d-Glucamine-Based Resorcin[4]arene Nanoparticles for Enhanced Apoptosis Effects

The addition of specific chemical groups in a macrocycle structure influences its functional properties and, consequently, can provide new possibilities, among which are aggregation properties, water solubility, biocompatibility, stimuli response, biological activity, etc. Herein, we report synthesis of new resorcin[4]arene with N-methyl-d-glucamine groups on the upper rim and n-decyl chains on the lower rim, an investigation of its self-assembly behavior in aqueous media, and its use as a building block for the formation of drug nanocontainer. N-methyl-d-glucamine fragments in the resorcin[4]arene structure promote higher stability in solutions, simplification of self-aggregation, and increased biological activity. Antimicrobial and hemolytic activity assessment revealed that this resorcin[4]arene obtained is nontoxic. The study of cell penetration was carried out with both free and encapsulated doxorubicin (DOX). Surprisingly, DOX-loaded macrocycle aggregates are more efficient in causing apoptosis in human cancer cell line. Conceivably, this knowledge will help in the rational design of DOX combination for novel drug-administration strategies in cancer treatment.