Comparison of cefpodoxime proxetil release and antimicrobial activity from tablet formulations: complexation with hydroxypropyl-β-cyclodextrin in the presence of water soluble polymer

Curcumin-loaded soluplus® based ternary solid dispersions with enhanced solubility, dissolution and antibacterial, antioxidant, anti-inflammatory activities

Amorphous solid dispersion (ASD) has emerged to be an outstanding strategy among multiple options available for improving solubility and consequently biological activity. Interestingly several binary SD systems continue to exhibit insufficient solubility over time. Therefore, the goal of current research was to design ternary amorphous solid dispersions (ASDs) of hydrophobic model drug curcumin (CUR) to enhance the solubility and dissolution rate in turn, presenting enhanced anti-bacterial, antioxidant and anti-inflammatory activity. For this purpose several ternary solid dispersions (TSDs) consisting of Soluplus®, Syloid® XDP 3150, Syloid® 244 and Poloxamer® 188 in combination with HPMC E5 (binary carrier) were prepared using solvent evaporation method. Both solubility and dissolution testing of prepared solid dispersion were performed to determine the increase in solubility and dissolution. Solid state investigation was carried out utilizing infrared spectroscopy, also known as Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM),Differential scanning calorimetry (DSC) and X-ray diffraction (XRD).Optimized formulations were also tested for their biological effectiveness including anti-bacterial, anti-oxidant and anti-inflammatory activity. Amid all Ternary formulations F3 entailing 20 % soluplus® remarkably improved the solubility (186 μg/ml ± 3.95) and consequently dissolution (91 % ± 3.89 %) of curcumin by 3100 and 9 fold respectively. These finding were also supported by FTIR, SEM, XRD and DSC. In-vitro antibacterial investigation of F3 also demonstrated significant improvement in antibacterial activity against both gram positive (Staphylococcus aureus, Bacillus cereus) and gram negative (Pseudomonas aeruginosa, Escherichia coli) bacteria. Among all the tested strains Staphylococcus aureus was found to be most susceptible with a zone of inhibition of 24 mm ± 2.87. Antioxidant activity of F3 was also notably enhanced (93 % ± 5.30) in contrast to CUR (69 % ± 4.79). In vitro anti-inflammatory assessment also exhibited that F3 markedly protected BSA (bovine serum albumin) from denaturation with percent BSA inhibition of 80 % ± 3.16 in comparison to CUR (49 % ± 2.91). Hence, F3 could be an effective solid dispersion system for the delivery of model hydrophobic drug curcumin.

Lab on chip based self-adjustable liposomes for rapid wound healing: An in depth in vitro, in vivo and higher dose toxicity investigation

Thanks to microfluidic technology, different nano-delivery systems are becoming clinically viable. Using a novel and rapid microfluidic hydrodynamic focusing (MHF) method (lipids on chip) we developed self-adaptable liposomes (SLs) containing cefpodoxime proxetil (CP) for the treatment of skin infections caused by Staphylococcus aureus. SLs were optimized using different flow rate ratios in the MHF method and the final formulation CPT3 was found to be the best in terms of particle size (68.27 ± 01.15 nm), % entrapment efficiency (% EE: 82 ± 1.5), polydispersity (PDI: 0.2 ± 0.012), and degree of deformability (DOD: 4.7 ± 0.18 nm). Rats (Sprague Dawley) treated with a self-adaptable CPT3 liposomal formulation recuperate skin injury, exhibited reduced bacterial counts (<106 CFU/mL) in the wounded region, and completely restored (100 %) on day 21. Rat survival, in vivo dermal pharmacokinetics and ex vivo-in vivo relationship were also investigated. Rats treated with an even 10-fold higher dose (100 mg/kg/day) of CP using an equivalent CPT3 formulation did not show any symptoms of toxicity as revealed by hematological, biochemical, and internal organ assessment observations. Finally, the developed CPT3 formulation with special interest in patients with high-risk skin injuries not only delivered CP in a controlled manner but was also clinically effective and safe as it did not produce any serious adverse events even at 10× higher doses in the infected rats.

Cyclodextrin Inclusion Complexes with Antibiotics and Antibacterial Agents as Drug-Delivery Systems—A Pharmaceutical Perspective

Cyclodextrins (CDs) are a family of cyclic oligosaccharides, consisting of a macrocyclic ring of glucose subunits linked by α-1,4 glycosidic bonds. The shape of CD molecules is similar to a truncated cone with a hydrophobic inner cavity and a hydrophilic surface, which allows the formation of inclusion complexes with various molecules. This review article summarises over 200 reports published by the end of 2021 that discuss the complexation of CDs with antibiotics and antibacterial agents, including beta-lactams, tetracyclines, quinolones, macrolides, aminoglycosides, glycopeptides, polypeptides, nitroimidazoles, and oxazolidinones. The review focuses on drug-delivery applications such as improving solubility, modifying the drug-release profile, slowing down the degradation of the drug, improving biological membrane permeability, and enhancing antimicrobial activity. In addition to simple drug/CD combinations, ternary systems with additional auxiliary substances have been described, as well as more sophisticated drug-delivery systems including nanosponges, nanofibres, nanoparticles, microparticles, liposomes, hydrogels, and macromolecules. Depending on the desired properties of the drug product, an accelerated or prolonged dissolution profile can be achieved when combining CD with antibiotics or antimicrobial agents.

Physical Characterization and In Vitro Evaluation of Dissolution Rate from Cefpodoxime Proxetil Loaded Self Solidifying Solid SNEDDS

BACKGROUND

Cefpodoxime Proxetil (CPD) is a broad-spectrum cephalosporin indicated in respiratory and urinary tract infections. CPD is a BCS class IV drug with pH-dependent solubility and has poor bioavailability. This study investigated the challenges of developing ternary components based on solid SNEDDS of CPD for in vitro dissolution rate enhancement and self-solidifying behaviour.

METHODS

Tween 80, Transcutol and PEG6000 were employed as surfactants, solvents and solidifiers for a base of ternary components to develop self-solidifying solid SNEDDS, respectively. Ternary phase diagrams were used to characterize solidifying behaviour of ternary components in different proportions. S-SNEDDS formulations were drawn on the solidification areas available in the phase diagram and characterized for IR, XRD, DSC and in vitro drug release in various pH media.

RESULTS

Ternary components for the preparation of self-solidifying solid SNEDDS were selected based on drug solubility. FTIR and DSC characterization studies ruled out any drug interaction between CPD and components chosen to prepare S-SNEDDS. CPD was transformed from a crystalline into an amorphous state in ternary dispersions as revealed from XRD data. Optimized formulation (S-S 1) demonstrated more than 95% of drug release irrespective of the pH environments of the medium. Calculation of dissolution efficiency and similarity factors indicate that S SNEDDS resulted in a higher drug dissolution rate over binary dispersion (p<0.01). The stability studies showed that the S SNEDDS were stable in performances and CPD assay.

CONCLUSION

The present investigation provides an alternative approach for enhancing the CPD dissolution rate using self-solidifying solid SNEDDS exhibited solidification behaviour at ambient temperature conditions and drug loading, which could be exploited over conventional dosage form.

Spray dried nanospheres for inclusion complexes of cefpodoxime proxetil with β-cyclodextrin, 2-hydroxypropyl-β-cyclodextrin and methyl-β-cyclodextrin: improved dissolution and enhanced antibacterial activity

OBJECTIVE

The aim of the current research was the development hard cellulose capsules containing cefpodoxime proxetil (CEF) (BCS-Class II) encapsulated nanospheres of inclusion complexes with β-CD, HP-β-CD and M-β-CD for efficient antibacterial therapy.

SIGNIFICANCE

The reason for this phenomenon is to bring an innovative approach to effective oral antimicrobial therapy with hard cellulose capsules containing spray dried nanospheres of CEF with β-CD, HP-β-CD and M-β-CD by means of increased solubility, dissolution rate and improved antibacterial efficiency with lower oral dose.

METHODS

Phase solubility analyses was performed to evaluate the drug/CD interaction, involving the stoichiometry and apparent stability constant. Following the preparation of inclusion complexes by spray-drying method, complexes were characterized for physical, solid-state and microbiological analyses. In vitro dissolution from hard cellulose capsules containing CEF and CEF/β-CD, CEF/HP-β-CD and CEF/M-β-CD complexes were performed.

RESULTS

According to AL type phase solubility curves, complexes were formulated as 1:1 molar ratio. The solubility of pure CEF was determined as 0.241 ± 0.002 mg mL-1, the solubility of inclusion complexes increased solubility from 3 to 5 times. The strong host-guest interaction was confirmed for CEF/HP-β-CD and CEF/M-β-CD complexes with SEM, DSC, FT-IR and 1H-NMR analyses. Inclusion complexes were more efficient on bacterial cells (2-4 fold) than pure CEF both Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae. Hard-cellulose capsules filled with inclusion complexes exhibited significantly faster release than unprocessed CEF.

CONCLUSION

Hard-cellulose capsules containing CEF/HP-β-CD and CEF/M-β-CD complexes appear to be superior alternative to commercially available CEF tablets for effective antibacterial therapy.

Development and characterization of lyophilized cefpodoxime proxetil-Pluronic® F127/polyvinylpyrrolidone K30 solid dispersions with improved dissolution and enhanced antibacterial activity

The aim of this study was the development of hard-cellulose capsules containing cefpodoxime proxetil (CEF) (BCS Class II) loaded novel Pluronic® F127 (P127)/Polyvinylpyrrolidone K30 (PVP) solid dispersions (SDs) using ultrasonic probe induced solvent-lyophilization method for effective antibacterial treatment by means of improved saturated aqueous solubility, dissolution rate, reduced particle size, and wettability. SDs were evaluated for physical and solid-state analyses. The solubility of pure CEF was calculated as 0.269 ± 0.005 mg/mL, SDs formulated with P127/PVP exhibited increased solubility from 3.5- to 8-fold. Molecular distribution of CEF in SDs and formation of CEF loaded amorphous polymeric network were confirmed with morphological study, thermal analysis, Fourier-transform infrared spectroscopy (FT-IR), and 1H-NMR studies. Staphylococcus aureus (ATCC 29213), Escherichia coli (ATCC 25922), and Klebsiella pneumoniae (ATCC 700603) were used to investigate the antibacterial effectiveness of the SDs. The minimum inhibitory concentration (MIC) values of the P127/PVP SDs were found 2-8 times lower than the pure CEF. All SDs from hard-cellulose capsules exhibited significantly faster release than unprocessed CEF. The profiles of SDs and reference were detected to be dissimilar according to difference (f1) and similarity factor (f2). Hard-cellulose capsules containing CEF loaded P127/PVP SDs appear to be feasible alternative to commercially available CEF tablets for effective antibacterial therapy at lowest dose.

Effect of Hydrophilic Polymers on Complexation Efficiency of Cyclodextrins in Enhancing Solubility and Release of Diflunisal

The effects of three hydrophilic polymers, namely, carboxymethyl cellulose sodium (CMC-Na), polyvinyl alcohol (PVA) and poloxamer-188 (PXM-188) on the solubility and dissolution of diflunisal (DIF) in complexation with β-cyclodextrin (βCD) or hydroxypropyl β-cyclodextrin (HPβCD), were investigated. The kneading method was used at different drug to cyclodextrin weight ratios. Increases in solubility and drug release were observed with the DIF/βCD and DIF/HPβCD complexes. The addition of hydrophilic polymers at 2.5, 5.0 and 10.0% w/w markedly improved the complexation and solubilizing efficiency of βCD and HPβCD. Fourier-transform infrared (FTIR) showed that DIF was successfully included into the cyclodextrin cavity. Differential scanning calorimetry (DSC) and X-ray diffractometry (XRD) confirmed stronger drug amorphization and entrapment in the molecular cage of cyclodextrins. The addition of PVA, CMC-Na or PXM-188 reduced further the intensity of the DIF endothermic peak. Most of the sharp and intense peaks of DIF disappeared with the addition of hydrophilic polymers. In conclusion, PXM-188 at a weight ratio of 10.0% w/w was the best candidate in enhancing the solubility, stability and release of DIF.

Cyclodextrin complexes for treatment improvement in infectious diseases

Infectious diseases are a heterogeneous group of maladies that represent a serious burden to healthcare systems worldwide. Most of the available antimicrobial drugs display poor biopharmaceutical properties that compromise their effectiveness. Cyclodextrins (CDs) are cyclic oligosaccharides of glucopyranose formed by a variable number of repeating units that combine a hydrophilic surface with a hydrophobic cavity. The production of drug/CD complexes has become one of the most extensively investigated technology approaches to improve the stability, solubility, dissolution rate and bioavailability of drugs. The present work overviews the applications of CDs for the formulation of anti-infective agents along with the most relevant administration routes. Finally, an update on the complexes with CDs available on the market to treat infectious diseases is presented.

Experimental and computational studies of physicochemical properties influence NSAID-cyclodextrin complexation

The objective of this research was to investigate physicochemical properties of an active pharmaceutical ingredient (API) that influence cyclodextrin complexation through experimental and computational studies. Native β-cyclodextrin (B-CD) and two hydroxypropyl derivatives were first evaluated by conventional phase solubility experiments for their ability to complex four poorly water-soluble nonsteroidal anti-inflammatory drugs (NSAIDs). Differential scanning calorimetry was used to confirm complexation. Secondly, molecular modeling was used to estimate Log P and aqueous solubility (S o) of the NSAIDs. Molecular dynamics simulations (MDS) were used to investigate the thermodynamics and geometry of drug-CD cavity docking. NSAID solubility increased linearly with increasing CD concentration for the two CD derivatives (displaying an AL profile), whereas increases in drug solubility were low and plateaued in the B-CD solutions (type B profile). The calculated Log P and S o of the NSAIDs were in good concordance with experimental values reported in the literature. Side chain substitutions on the B-CD moiety did not significantly influence complexation. Explicitly, complexation and the associated solubility increase were mainly dependent on the chemical structure of the NSAID. MDS indicated that each NSAID-CD complex had a distinct geometry. Moreover, complexing energy had a large, stabilizing, and fairly constant hydrophobic component for a given CD across the NSAIDs, while electrostatic and solvation interaction complex energies were quite variable but smaller in magnitude.