Transformation of eutectic emulsion to nanosuspension fabricating with solvent evaporation and ultrasonication technique

Menthol-Based (Deep) Eutectic Solvents: A Review on Properties and Application in Extraction

In the last 10 years the interest in deep eutectic solvents (DESs) as a new class of green solvents has considerably increased. The emergence of numerous of hydrophobic DESs has stimulated intensive research into their application in extraction technologies, including sample preparation. As the properties of such systems are highly dependent on the properties of their components (hydrogen bond donors and acceptors) and can be finely tuned, DESs can be successfully used for the extraction of both metal ions and organic substances, including biomolecules. Despite the rapidly increasing number of publications on the use of DESs as an extraction medium, including review articles, information on the extraction properties of DESs in terms of their chemical composition has not yet been summarized. This review covers available literature data on the physicochemical properties of menthol-based eutectic solvents and the results of their practical application as an extraction medium. Also, the appropriateness of using the term "DES" for all mixtures with melting points lower than the melting points of their components is discussed.

Lopinavir-menthol co-crystals for enhanced dissolution rate and intestinal absorption

Lopinavir is an antiretroviral, antiparasitic agent and recently utilized in treatment of COVID-19. Unfortunately, lopinavir exhibited poor oral bioavailability due to poor dissolution, extensive pre-systemic metabolism, and significant P-glycoprotein intestinal efflux. Accordingly, the aim was to enhance dissolution rate and intestinal absorption of lopinavir. This employed co-processing with menthol which is believed to modify crystalline structures and inhibit intestinal efflux. Lopinavir was mixed with menthol at different molar ratios before ethanol assisted kneading. Formulations were evaluated using FTIR spectroscopy, differential scanning calorimetry (DSC), X-ray powder diffraction (XRD) and dissolution studies. Optimum ratio was utilized to assess lopinavir intestinal permeability. This employed in situ rabbit intestinal perfusion technique. FTIR, DSC and XRD indicated formation of lopinavir-menthol co-crystals at optimum molar ratio of 1:2. Additional menthol underwent phase separation due to possible self-association. Co-crystallization significantly enhanced lopinavir dissolution rate compared with pure drug to increase the dissolution efficiency from 24.96% in case of unprocessed lopinavir to 91.43% in optimum formulation. Lopinavir showed incomplete absorption from duodenum and jejuno-iliac segments with lower absorptive clearance from jejuno-ileum reflecting P-gp efflux. Co-perfusion with menthol increased lopinavir intestinal permeability. The study introduced menthol as co-crystal co-former for enhanced dissolution and augmented intestinal absorption of lopinavir.

Photolytic Removal of Red Blood Cell Membranes Camouflaged on Nanoparticles for Enhanced Cellular Uptake and Combined Chemo-Photodynamic Inhibition of Cancer Cells

Biomimetic therapeutics offer great potential for drug delivery that avoids immune recognition. However, the coated cell membrane usually hinders the cellular uptake of nanoparticles; thus, structure-changeable formulations have attracted increasing attention. Herein, we report photolytic pyropheophorbide a (PA)-inserted red blood cell (RBC) membrane-camouflaged curcumin dimeric prodrug (CUR₂-TK)-poly(lactic-co-glycolic acid) (PLGA) nanoparticles [(CUR₂-TK)-PLGA@RBC-PA] for enhanced cancer therapy. In these nanoparticles, the inner core was constructed using PLGA and loaded with our synthesized reactive oxygen species (ROS)-responsive cleavable curcumin dimeric prodrug (CUR₂-TK). The nanoparticles generated ROS in response to the light irradiation attributed to the incorporated PA. The ROS further triggered the lysis of the cell membrane and exposed the nanoparticles for enhanced tumor cellular uptake, and the ROS also cleaved CUR₂-TK for controlled CUR drug release. Moreover, the ROS performed photodynamic therapy (PDT). The chemotherapy and PDT produced a combined effect in the treatment of cancer cells, thus enhancing anticancer therapeutic efficacy.

Bioresponsive micro-to-nano albumin-based systems for targeted drug delivery against complex fungal infections

As a typical human pathogenic fungus, Cryptococcus neoformans is a life-threatening invasive fungal pathogen with a worldwide distribution causing ∼700,000 deaths annually. Cryptococcosis is not just an infection with multi-organ involvement, intracellular survival and extracellular multiplication of the fungus also play important roles in the pathogenesis of C. neoformans infections. Because adequate accumulation of drugs at target organs and cells is still difficult to achieve, an effective delivery strategy is desperately required to treat these infections. Here, we report a bioresponsive micro-to-nano (MTN) system that effectively clears the C. neoformans in vivo. This strategy is based on our in-depth study of the overexpression of matrix metalloproteinase 3 (MMP-3) in infectious microenvironments (IMEs) and secreted protein acidic and rich in cysteine (SPARC) in several associated target cells. In this MTN system, bovine serum albumin (BSA, a natural ligand of SPARC) was used for the preparation of nanoparticles (NPs), and then microspheres were constructed by conjugation with a special linker, which mainly consisted of a BSA-binding peptide and an MMP-3-responsive peptide. This MTN system was mechanically captured by the smallest capillaries of the lungs after intravenous injection, and then hydrolyzed into BSA NPs by MMP-3 in the IMEs. The NPs further targeted the lung tissue, brain and infected macrophages based on the overexpression of SPARC, reaching multiple targets and achieving efficient treatment. We have developed a size-tunable strategy where microspheres "shrink" to NPs in IMEs, which effectively combines active and passive targeting and may be especially powerful in the fight against complex fungal infections.

Hot-Melt 3D Extrusion for the Fabrication of Customizable Modified-Release Solid Dosage Forms

In this work, modified-release solid dosage forms were fabricated by adjusting geometrical properties of solid dosage forms through hot-melt 3D extrusion (3D HME). Using a 3D printer with air pressure driving HME system, solid dosage forms containing ibuprofen (IBF), polyvinyl pyrrolidone (PVP), and polyethylene glycol (PEG) were printed by simultaneous HME and 3D deposition. Printed solid dosage forms were evaluated for their physicochemical properties, dissolution rates, and floatable behavior. Results revealed that IBF content in the solid dosage form could be individualized by adjusting the volume of solid dosage form. IBF was dispersed as amorphous state with enhanced solubility and dissolution rate in a polymer solid dosage form matrix. Due to absence of a disintegrant, sustained release of IBF from printed solid dosage forms was observed in phosphate buffer at pH 6.8. The dissolution rate of IBF was dependent on geometric properties of the solid dosage form. The dissolution rate of IBF could be modified by merging two different geometries into one solid dosage form. In this study, the 3D HME process showed high reproducibility and accuracy for preparing dosage forms. API dosage and release profile were found to be customizable by modifying or combining 3D modeling.

Exploring the novel green eutectic solvent for the synthesis of 4-hydroxy-2-methyl-N-2-pyridinyl-2H-1,2,-benzothiazine-3-carboxamide 1,1-dioxide with benzoic acid cocrystal using a co-grinding technique

In the present study, the suitability of a green eutectic solvent, a mixture of menthol and camphor for cocrystal synthesis has been investigated to improve the biopharmaceutical properties of poorly water-soluble drugs.

FSE-Ag complex NS: preparation and evaluation of antibacterial activity

Silver (Ag) complexes of drugs and their nanosystems have great potential as antibacterials. Recently, an Ag complex of furosemide (Ag-FSE) has shown to be a promising antimicrobial. However, poor solubility of Ag-FSE could hamper its introduction into clinics. Therefore, the authors developed a nanosuspension of Ag-FSE (Ag-FSE_NS) for its solubility and antibacterial activity enhancement. The aim of this study was to introduce a novel nanoantibiotic with enhanced antibacterial efficacy. Ag-FSE_NS was prepared by precipitation-ultrasonication technique. Size, polydispersity index (PI) and zeta potential (ZP) of prepared Ag-FSE_NS were measured by dynamic light scattering, whereas surface morphology was determined using scanning electron microscopy (SEM). In vitro antibacterial activity was evaluated against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa using broth microdilution method. Size, PI and ZP of optimised Ag-FSE_NS1 were 191.2 ± 19.34 nm, 0.465 ± 0.059 and -55.7 ± 8.18 mV, respectively. SEM revealed that Ag-FSE_NS1 particles were rod or needle-like with smooth surfaces. Saturation solubility of Ag-FSE in NS increased eight-fold than pure Ag-FSE. Ag-FSE_NS1 exhibited two-fold and eight-fold enhancements in activity against E. coli and S. aureus, respectively. The results obtained showed that developed Ag-FSE_NS1 holds a promise as a topical antibacterial.