Pharmaceutical suspension containing both immediate/sustained-release amoxicillin-loaded gelatin nanoparticles: preparation and in vitro characterization

Preparation, characterization, and evaluation of antibacterial and cytotoxic activity of chitosan-polyethylene glycol nanoparticles loaded with amoxicillin as a novel drug delivery system

In this study, nanoparticles of amoxicillin (AMX) were prepared using chitosan (CHI) and polyethylene glycol (PEG). The physicochemical properties of the particles were investigated by FT-IR, DSC, SEM, and zeta potential analyses. The nanoparticles showed a spherical shape, and the average size of formulations was within the range of 696.20 ± 24.86 - 359.53 ± 7.41 nm. Zeta potential data demonstrated that the formulations had positive surface charges with a zeta potential range of 21.38 ± 2.28 - 7.73 ± 1.66 mV. FTIR analysis showed that the drug was successfully entrapped in the nanoparticles. DSC results suggested that the drug was present in amorphous form in the polymer matrix. In vitro release studies demonstrated that the release pattern consisted of two phases, with an initial burst release followed by a controlled and sustained release. The MTT assay results on mouse fibroblast cell line indicated that the prepared formulations did not affect the viability of the cells. In the in vitro antibacterial activity test, it was found that the drug-loaded nanoparticles have AMX-equivalent antibacterial activity against E. coli, and S. aureus. These findings revealed that the obtained nanoparticles might be a promising and safe nanocarrier system for efficient delivery of AMX.

Pharmaceutical and Pharmacological Evaluation of Amoxicillin after Solubility Enhancement Using the Spray Drying Technique

The dose frequency of drugs belonging to class II is usually high and associated with harmful effects on the body. The study aimed to enhance the solubility of the poorly water-soluble drug amoxicillin (AM) by the solid dispersion (SD) technique. Six different SDs of AM, F1-F6, were prepared by the spray drying technique using two other carriers, HP-β-CD (F1-F3) and HPMC (F4-F6), in 1:1, 1:2, and 1:3 drug-to-polymer ratios. These SDs were analyzed to determine their practical yield, drug content, and aqueous solubility using analytical techniques such as Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, and powder X-ray diffraction. The effect of polymer concentration on SDs was determined using aqueous solubility, in vitro dissolution, and in vivo studies. The results showed no drug-polymer interactions in SDs. Solubility studies showed that SDs based on the drug-to-polymer ratio of 1:2 (F2 and F5) were highly soluble in water compared to those with ratios of 1:1 and 1:3. In vitro dissolution studies also showed that SDs with a ratio of 1:2 released the highest drug concentration from both polymeric systems. The SDs based on HPMC confirmed the more sustained release of the drug as compared to that of HP-β-CD. All the SDs were observed as stable and amorphous, with a smooth spherical surface. In vivo studies reveal the enhancement of pharmacokinetics parameters as compared to standard AM. Hence, it is confirmed that spray drying is an excellent technique to enhance the solubility of AM in an aqueous medium. This may contribute to the enhancement of the pharmacokinetic behaviors of SDs.

A Micro-Configured Multiparticulate Reconstitutable Suspension Powder of Fixed Dose Rifampicin and Pyrazinamide: Optimal Fabrication and In Vitro Quality Evaluation

The scarcity of age-appropriate pharmaceutical formulations is one of the major challenges impeding successful management of tuberculosis (TB) prevalence in minors. To this end, we designed and assessed the quality of a multiparticulate reconstitutable suspension powder containing fixed dose rifampicin and pyrazinamide (150 mg/300 mg per 5 mL) which was prepared employing solid−liquid direct dispersion coupled with timed dehydration, and mechanical pulverization. The optimized formulation had a high production yield (96.000 ± 3.270%), displayed noteworthy powder flow quality (9.670 ± 1.150°), upon reconstitution the suspension flow property was non-Newtonian and was easily redispersible with gentle manual agitation (1.720 ± 0.011 strokes/second). Effective drug loading was attained for both pyrazinamide (97.230 ± 2.570%w/w) and rifampicin (97.610 ± 0.020%w/w) and drug release followed a zero-order kinetic model (R2 = 0.990) for both drugs. Microscopic examinations confirmed drug encapsulation efficiency and showed that the particulates were micro-dimensional in nature (n < 700.000 µm). The formulation was physicochemically stable with no chemically irreversible drug-excipient interactions based on the results of characterization experiments performed. Findings from organoleptic evaluations generated an overall rating of 4.000 ± 0.000 for its attractive appearance and colour 5.000 ± 0.000 confirming its excellent taste and extremely pleasant smell. Preliminary cytotoxicity studies showed a cell viability above 70.000% which indicates that the FDC formulation was biocompatible. The optimized formulation was environmentally stable either as a dry powder or reconstituted suspension. Accordingly, a stable and palatable FDC antimycobacterial reconstitutable oral suspension powder, intended for flexible dosing in children and adolescents, was optimally fabricated.

Nano Spray-Dried Drugs for Oral Administration: A Review

Spray drying is an important technology that is fast, simple, reproducible, and scalable. It has a wide application range, that is, in food, chemicals, and encapsulation of pharmaceuticals. The technology can be divided into conventional spray drying and nano spray drying. The key advantage of nano spray drying is the production of drug-loaded nanosized particles for various drug delivery applications. The recent developments in nano spray dryer technology and the market launch of the Nano Spray Dryer B-90 by Büchi Labortechnik AG in 2009 enabled the production of submicron spray-dried particles. This review focuses on nanosized drug delivery systems intended for oral administration produced by nano spray drying. First, the nano spray drying concept, the basic technologies implemented in the equipment, and the effects of the various process parameters on the final dry submicron powder properties are presented. Then, the topics of new formulation strategies of oral drugs are highlighted with examples that have entered the research literature in recent years. Next, the subjects of direct conversion of poorly water-soluble drugs, encapsulation of drugs, and drying of preformed nanoparticles are considered. Finally, topics such as morphology, particle size, size distribution, surface analysis, bioavailability, drug release, release kinetics, and solid-state characterization (by differential scanning calorimetry, X-ray diffraction, Fourier transform infrared spectroscopy, nuclear magnetic resonance) of oral drug delivery systems produced by nano spray drying are discussed. The review attempts to provide a comprehensive knowledge base with current literature and foresight to researchers working in the field of pharmaceutical technology and nanotechnology and especially in the field of nano spray drying.

Synthesis and characterization of amoxicillin-loaded polymeric nanocapsules as a drug delivery system targeting Helicobacter pylori

BACKGROUND AND STUDY AIMS

Helicobacter pylori (H. pylori) is well known as the main cause of gastritis, gastroduodenal ulcers, gastric mucosa-associated lymphoid tissue lymphoma, and gastric cancer. Approximately 50% of the world's population is infected with H. pylori. In Egypt, a high prevalence of H. pylori infections has been reported in the general population. This study aimed to prepare amoxicillin-loaded poly (ɛ-caprolactone) nanocapsules to increase its gastric stability and therapeutic activity of the molecule against H. pylori.

MATERIALS AND METHODS

In this study, we used the water-oil-water double-emulsion technique to prepare spherical-shaped polymeric nanocapsules containing amoxicillin trihydrate as the core substance and biodegradable biocompatible poly (ɛ-caprolactone) as the shell material.

RESULTS

The encapsulation efficiency obtained was 97.2% ± 0.8%. The hydrodynamic diameter of the prepared nanocapsules was 287 ± 8 nm with a positive zeta potential. In vitro release studies indicated that the polymeric nanocapsules showed decreased release percentages at pH 1.2, simulating the gastric fluid while relatively increased release at pH 7.0 where the H. pylori reside. The in vitro antibacterial assay showed better efficiency for amoxicillin nanocapsules than for the uncapsulated free amoxicillin, no efficiency was detected for the PCL nanocapsules indicated that the antibacterial due to amoxicillin alone. Cytotoxicity studies demonstrated less cytotoxicity for the polymeric nanocapsules in comparison with amoxicillin.

CONCLUSIONS

In conclusion, we have demonstrated that biodegradable polymeric nanocapsules are useful drug delivery agents for increasing the gastric stability and therapeutic activity of amoxicillin trihydrate against H. pylori.

Synthesis of biopolymeric particles loaded with phosphorus and potassium: characterisation and release tests

The authors synthesised nanoparticles (NPs) loaded with P and K from KH2 PO4 using gelatin type‐A and type‐B, and sodium alginate as carriers. Using type‐A and type‐B gelatin, quasi‐spherical particles were obtained, with average sizes of 682 and 856 nm, respectively; with sodium alginate, the resulting NPs exhibited spherical shapes and 600 nm particle average size. The authors found an interaction between KH2 PO4 and alginate via the hydrogen bonds existent among the carboxylic groups of the carbohydrate and the OH‐groups of the H2 PO4 ‐; interactions among gelatin types with the OH‐groups and the H2 PO4 ‐ion were also observed. Adding trypsin to the distilled water solutions of the NPs coated with type‐A gelatin increased the concentration of P in the solution by threefold, while increasing that of K increased by 2.6‐fold. Conversely, adding α ‐amylase to the water solutions with sodium alginate increased the P and K concentrations in the solution by nearly 1.3‐ and 1.1‐fold, respectively. Thus, sodium alginate resulted in NPs with smaller sizes and better spherical formations, though with a high polydispersity index and lower release rate of P and K . This low release rate represents an advantage since plants demand nutrients for long periods, and conventional fertilisers display low use efficiency.

Influence of PDLA nanoparticles size on drug release and interaction with cells

Polymeric nanoparticles (NPs) are strong candidates for the development of systemic and targeted drug delivery applications. Their size is a determinant property since it defines the NP-cell interactions, drug loading capacity, and release kinetics. Herein, poly(d,l-lactic acid) (PDLA) NPs were produced by the nanoprecipitation method, in which the influence of type and concentration of surfactant as well as PDLA concentration were assessed. The adjustment of these parameters allowed the successful production of NPs with defined medium sizes, ranging from 80 to 460 nm. The surface charge of the different NPs populations was consistently negative. Prednisolone was effectively entrapped and released from NPs with statistically different medium sizes (i.e., 80 or 120 nm). Release profiles indicate that these systems were able to deliver appropriate amounts of drug with potential applicability in the treatment of inflammatory conditions. Both NPs populations were cytocompatible with human endothelial and fibroblastic cells, in the range of concentrations tested (0.187-0.784 mg/mL). However, confocal microscopy revealed that within the range of sizes tested in our experiments, NPs presenting a medium size of 120 nm were able to be internalized in endothelial cells. In summary, this study demonstrates the optimization of the processing conditions to obtain PDLA NPs with narrow size ranges, and with promising performance for the treatment of inflammatory diseases. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 482-493, 2019.

Chemotherapeutic drug targeting to lungs by way of microspheres after intravenous administration

Purpose

Currently, microsphere technology plays a major role in the development of many new cancer therapies. In the current study, we proposed a targeted drug-delivery system to improve the treatment efficacy of one of the common conventional chemotherapeutic drugs used to treat lung tumors, 5-fluorouracil (5-FU).

Materials and methods

Following the preparation and optimization of small, solid micro-spheres, ranging in diameter between 5 and 15 µm, the final product 5-fluorouracil gelatin (5-FUG) was formulated using a Buchi Nano Spray Dryer by varying the drug:polymer ratio.

Results

Particle yield was calculated as 65% ± 1.2%, and the drug content in the formulation was recorded as 74% ± 1.6%. Particle surface morphology was examined as shriveled shape (crumpled/folded); particle size distribution displayed a binomial distribution, with a mean diameter of 9.6 µm. In vitro drug release studies revealed that ~36.4% of the 5-FU in 5-FUG was released in the first hour after injection. Clinically, this would lead to initial or burst release, facilitating a quick rise to therapeutic levels. In contrast to the pure 5-FU drug (89.2% of the drug released in the first 30 minutes), 99.1% of the drug in 5-FUG was released from the spray-dried particles for a period of 12 hours. A two-compartment model was used to generate plasma concentration–time curves. 5-FUG injection has a much different distribution in vivo in contrast to intravenous injection of 5-FU. In addition, the half-life after intravenous injection of 5-FUG, t_1/2(α) = 1.23 hours and t_1/2(β) = 18.3 hours, was considerably longer than that of 5-FU, t_1/2(α) = 0.34 hours and t_1/2(β) = 8.62 hours. Examination of stained lung tissue sections showed no histopathological tissue changes or evidence of gross pathology. In addition, the optimized formulation demonstrated an increased stability under both long-term and refrigerated storage conditions.

Conclusion

Our goal was to develop similar delivery systems for other chemotherapeutic drugs that are site specific to different disease models/tumor types.

Solid lipid nanoparticles for thermoresponsive targeting: evidence from spectrophotometry, electrochemical, and cytotoxicity studies

Thermoresponsive drug delivery systems are designed for the controlled and targeted release of therapeutic payload. These systems exploit hyperthermic temperatures (>39°C), which may be applied by some external means or due to an encountered symptom in inflammatory diseases such as cancer and arthritis. The objective of this paper was to provide some solid evidence in support of the hypothesis that solid lipid nanoparticles (SLNs) can be used for thermoresponsive targeting by undergoing solid–liquid phase transition at their melting point (MP). Thermoresponsive lipid mixtures were prepared by mixing solid and liquid natural fatty acids, and their MP was measured by differential scanning calorimetry (DSC). SLNs (MP 39°C) containing 5-fluorouracil (5-FU) were synthesized by hot melt encapsulation method, and were found to have spherical shape (transmission electron microscopy studies), desirable size (<200 nm), and enhanced physicochemical stability (Fourier transform infrared spectroscopy analysis). We observed a sustained release pattern (22%–34%) at 37°C (5 hours). On the other hand, >90% drug was released at 39°C after 5 hours, suggesting that the SLNs show thermoresponsive drug release, thus confirming our hypothesis. Drug release from SLNs at 39°C was similar to oleic acid and linoleic acid nanoemulsions used in this study, which further confirmed that thermoresponsive drug release is due to solid–liquid phase transition. Next, a differential pulse voltammetry-based electrochemical chemical detection method was developed for quick and real-time analysis of 5-FU release, which also confirmed thermoresponsive drug release behavior of SLNs. Blank SLNs were found to be biocompatible with human gingival fibroblast cells, although 5-FU-loaded SLNs showed some cytotoxicity after 24 hours. 5-FU-loaded SLNs showed thermoresponsive cytotoxicity to breast cancer cells (MDA-MB-231) as cytotoxicity was higher at 39°C (cell viability 72%–78%) compared to 37°C (cell viability >90%) within 1 hour. In conclusion, this study presents SLNs as a safe, simple, and effective platform for thermoresponsive targeting.

Nano Spray Drying Technique as a Novel Approach To Formulate Stable Econazole Nitrate Nanosuspension Formulations for Ocular Use

The effect of using methyl-β-cyclodextrin and hydroxypropyl-β-cyclodextrin as carriers for econazole nitrate nanoparticles prepared by nano spray dryer was explored in this work. Stabilizers, namely, poly(ethylene oxide), polyvinylpyrrolidone k30, poloxamer 407, Tween 80, and Cremophor EL, were used. The nano spray dried formulations revealed almost spherical particles with an average particle size values ranging from 121 to 1565 nm and zeta potential values ranging from -0.8 to -2.5 mV. The yield values for the obtained formulations reached 80%. The presence of the drug in the amorphous state within the nanosuspension matrix system significantly improved drug release compared to that for pure drug. Combination of hydroxypropyl-β-cyclodextrin with Tween 80 achieved an important role for preserving the econazole nanosuspension from aggregation during storage for one year at room temperature as well as improving drug release from the nanosuspension. This selected formulation was suspended in chitosan HCl to increase drug release and bioavailability. The in vivo evaluation on albino rabbit's eyes demonstrated distinctly superior bioavailability of the selected formulation suspended in chitosan compared to its counterpart formulation suspended in buffer and crude drug suspension due to its mucoadhesive properties and nanosize. The nano spray dryer could serve as a one step technique toward formulating stable and effective nanosuspensions.

NANOPARTICLES. Production of amorphous nanoparticles by supersonic spray-drying with a microfluidic nebulator

Amorphous nanoparticles (a-NPs) have physicochemical properties distinctly different from those of the corresponding bulk crystals; for example, their solubility is much higher. However, many materials have a high propensity to crystallize and are difficult to formulate in an amorphous structure without stabilizers. We fabricated a microfluidic nebulator that can produce amorphous NPs from a wide range of materials, even including pure table salt (NaCl). By using supersonic air flow, the nebulator produces drops that are so small that they dry before crystal nuclei can form. The small size of the resulting spray-dried a-NPs limits the probability of crystal nucleation in any given particle during storage. The kinetic stability of the a-NPs—on the order of months—is advantageous for hydrophobic drug molecules.

Eradication of Helicobacter pylori: Past, present and future

Helicobacter pylori is the major cause of chronic gastritis and peptic ulcers. Since the classification as a group 1 carcinogenic by International Agency for Research on Cancer, the importance of the complete H. pylori eradication has obtained a novel meaning. Hence, several studies have been made in order to deepen the knowledge in therapy strategies. However, the current therapy presents unsatisfactory eradication rates due to the lack of therapeutic compliance, antibiotic resistance, the degradation of antibiotics at gastric pH and their insufficient residence time in the stomach. Novel approaches have been made in order to overcome these limitations. The purpose of this review is to provide an overview about the current therapy and its limitations, while highlighting the possibility of using micro- and nanotechnology to develop gastric drug delivery systems, overcoming these difficulties in the future.