Polymer Ratio Research Articles

Formulation and Evaluation of Floating Tablet of Nabumetone

Nabumetone was used as a model drug in this study to construct and assess floating tablets. By adjusting the drug to polymer ratio to 1:1, 1:1.5, and 1:2, naproxen sodium floating tablets were made utilising the wet granulation method. As generating agents, sodium bicarbonate and citric acid are utilised. With isopropyl alcohol acting as the solvent, lactose is employed as diluents and PVP K30 as a granulating agent. The formulation of the granules was assessed for flow properties, and the tablets were made and assessed for physical characteristics, invitro buoyancy testing, and drug content. All of the formulations displayed values that were within the permitted range, demonstrating the high calibre of the manufactured tablets. A decrease in the density of the tablet below 1 and the emergence of buoyancy were noticed as a result of the gas created being confined and protected within the gel formed by the polymers. As the polymer to drug ratio increases, it was seen that the floating lag time in the formulations F1 to F6 decreased while the total floating duration increased. Drug release from the formulations made in a 1:1 ratio occurred at a higher rate and to a greater extent (i.e. F1, F4, and F7). The produced tablets underwent evaluations for uniformity, hardness, friability, drug content, in vitro buoyancy experiments, and dissolving investigations. In addition, the invitro release data were fitted to various kinetic models.

Formulation, optimization and characterization of raloxifene hydrochloride loaded PLGA nanoparticles by using Taguchi design for breast cancer application.

Multidrug resistance in breast cancer and the associated side-effects of anticancer therapies are significant hurdles in chemotherapy-based treatment. Biodegradable polymeric nano-based targeted drug delivery technologies showed tremendous advantages in targeted local delivery with limited off-targeted side effects. Therefore, there is a persistent need to develop targeted nanomedicine systems for treatment of breast cancer. The current research attempted to develop poly (lactic-co-glycolic acid) nanoparticles loaded with raloxifene by modified emulsification solvent diffusion evaporation method to improve oral bioavailability by using Taguchi design. It was observed that the optimized formulation (1:4 drug to polymer ratio) poly (lactic-co-glycolic acid) showed a mean particle size and Polydispersity index of 218 ± 23.7nm and 0.231 ± 0.04, respectively. The entrapment efficiency was found to be 82.30% ± 1.02%. In vitro drug delivery was found to be 92.5% ± 1.48% in 40 h. The nanoparticles were to remain stable at 2°C-8°C even after 30 days. Differential scanning calorimetry and Fourier transform infrared spectroscopy characterization techniques showed that there was no interaction between the drug and excipient. Stability studies indicate that polymeric nanoparticles were stable at 2°C-8°C after 6months. Raloxifene nanoparticles may be the most potent targeting moieties to treat highly invasive and metastatic MCF-7 breast cancer cells.

Hybrid Fluoro-Based Polymers/Graphite Foil for H2/Natural Gas Separation

Membrane technologies and materials development appear crucial for the hydrogen/natural gas separation in the impending transition to the hydrogen economy. Transporting hydrogen through the existing natural gas network could result less expensive than a brand-new pipe system. Currently, many studies are focused on the development of novel structured materials for gas separation applications, including the combination of various kind of additives in polymeric matrix. Numerous gas pairs have been investigated and the gas transport mechanism in those membranes has been elucidated. However, the selective separation of high purity hydrogen from hydrogen/methane mixtures is still a big challenge and nowadays needs a great improvement to promote the transition towards more sustainable energy source. In this context, because of their remarkable properties, fluoro-based polymers, such as PVDF-HFP and NafionTM, are among the most popular membrane materials, even if a further optimization is needed. In this study, hybrid polymer-based membranes were deposited as thin films on large graphite surfaces. Different weight ratios of PVDF-HFP and NafionTM polymers supported over 200 μm thick graphite foils were tested toward hydrogen/methane gas mixture separation. Small punch tests were carried out to study the membrane mechanical behaviour, reproducing the testing conditions. Finally, the permeability and the gas separation activity of hydrogen/methane over membranes were investigated at room temperature (25 °C) and near atmospheric pressure (using a pressure difference of 1.5 bar). The best performance of the developed membranes was registered when the 4:1 polymer PVDF-HFP/NafionTM weight ratio was used. In particular, starting from the 1:1 hydrogen/methane gas mixture, a 32.6% (v%) H2 enrichment was measured. Furthermore, there was a good agreement between the experimental and theoretical selectivity values.

Preparation and characterization of fast-release oral film formulation containing ondansetron hydrochloride solid dispersion

Ondansetron has been widely applied as an antiemetic drug in the treatment or prevention of nausea and vomiting caused by emetic cancer chemotherapy . Fast-release films have the advantages of rapid drug release and improved patients’compliance, especially for the disabled bedridden, the elderly or pediatric patients.The basic film-forming materials were studied through single factor tests and the crystal inhibitors were optimized using solid dispersion technique. The ratio of drug and polymers were optimized by X-ray diffraction (XRD) and Differential Scanning Calorimetry (DSC) which revealed there was no presence of crystal in the optimized solid dispersion. The final film was white thin films and was smooth in surface without obvious bubbles or cracks. Mean weight of each film was 40~50mg. Mean thichness was 60~70μm. Surface pH was 6.4~6.6. The films could release 85% of drug with 1.5min in 0.1mol/L HCl and within 30min in pH6.8PBS. Pharmacolinetic experiment of Ondansetron Hydrochloric solution, marketed films Zuplenz® and the preparation were carried out in rats. As a result, the films of Ondansetron Hydrochloric containing ondansetron solid dispersion had the advantages of fast drug release, improved patient compliance, higher bioavalibility compared to oral solution and the marketed films.

Combination of Dissolving Microneedles with Nanosuspension and Co-Grinding for Transdermal Delivery of Ketoprofen.

Ketoprofen is an anti-inflammatory agent that may cause gastric irritation if administered orally. Dissolving microneedles (DMN) can be a promising strategy to overcome this issue. However, ketoprofen has a low solubility; therefore, it is essential to enhance its solubility using certain methods, namely nanosuspension (NS) and co-grinding (CG). This research aimed to formulate DMN containing ketoprofen-loaded NS and CG. Ketoprofen NS was formulated with poly(vinyl alcohol) (PVA) at concentrations of 0.5%, 1%, and 2%. CG was prepared by grinding ketoprofen with PVA or poly(vinyl pyrrolidone) (PVP) at different drug-polymer ratios. The manufactured ketoprofen-loaded NS and CG were evaluated in terms of their dissolution profile. The most promising formulation from each system was then formulated into microneedles (MNs). The fabricated MNs were assessed in terms of their physical and chemical properties. An in vitro permeation study using Franz diffusion cells was also carried out. The most promising MN-NS and MN-CG formulations were F4-MN-NS (PVA 5%-PVP 10%), F5-MN-NS (PVA 5%-PVP 15%), F8-MN-CG (PVA 5%-PVP 15%), and F11-MN-CG (PVA 7.5%-PVP 15%), respectively. The cumulative amounts of drug permeated after 24 h for F5-MN-NS and F11-MN-CG were 3.88 ± 0.46 µg and 8.73 ± 1.40 µg, respectively. In conclusion, the combination of DMN with nanosuspension or a co-grinding system may be a promising strategy for delivering ketoprofen transdermally.

Incorporating sodium deoxycholate endorsed the buccal administration of avanafil to heighten the bioavailability and duration of action.

The highly effective phosphodiesterase type 5 inhibitor (avanafil; AVA) is routinely prescribed to treat erectile dysfunction. The drug has poor oral bioavailability and undergoes a significant first-pass metabolism. Therefore, altering AVA's solubility and choosing a different delivery method may boost its effectiveness. Nine different solid dispersion formulations utilizing polyvinylpyrrolidone (PVP) at three different ratios were prepared and characterized. The Box-Behnken design was employed to optimize AVA-buccal tablets. The pre-compression and post-compression characteristics of the tablets were assessed. The mucoadhesion strength of the optimized tablet was investigated using cow buccal mucosal tissue. In vivo performance of the optimized tablets was examined on human volunteers compared to the commercial tablets. PVP K90 at 2:1 drug to polymer ratio showed the highest solubilization capacity. The mucoadhesive polymer type and percentage and the mucopenetration enhancer percentage were significantly affect the mucoadhesion strength, tablet hardness, and the initial and cumulative AVA released from the prepared tablets. The optimized AVA-buccal tablet showed 4.96 folds increase in the mean residence time, higher plasma exposure, and an improvement in the relative bioavailability of AVA by 1076.27% compared with the commercial tablet. Therefore, a successful approach to deal with AVA first-pass metabolism and low bioavailability could be to employ buccal tablets containing a solubility-enhanced form of AVA.

Oil-in-water emulsion gels stabilized with cellulosic polymers and chitosan: Themorheological and physical-chemical evaluation

This research evaluated the use of different polymer ratios, hydroxypropyl methylcellulose (HPMC) and methylcellulose (MC) with chitosan (CHI), in the production of emulgel by emulsification. The concentration was fixed at 2 % (w/v) for all polymers. 60/40 sunflower oil-in-water emulgels were made with a cellulosic polymer:chitosan ratio of (80:20), (70:30), and (60:40), respectively. The objective was to study how different proportions of a cellulosic polymer combined with chitosan can affect the stability, microstructure, and rheology of the emulgels to be used as potential oil carrier systems. Droplet size and microscopy results show oil-in-water (O/W) emulgels, and their interface was stabilized by mixing polymeric pairs, HPMC:CHI or MC:CHI. In the thermal analysis, it was identified in the entire temperature range studied (5 to 85 °C) that both emulgels, HPMC:CHI and MC:CHI, were presented as gels (G′ > G″). Thus, the addition of CHI to the systems modified their gelling behavior. Microscopy revealed that the emulsions at the 7th and 10th week of storage showed similar characteristics to the fresh emulsion. Therefore, these results indicate that the emulgels present good thermal resistance, the predominance of elastic behavior, and can retain high concentrations of oil in their structure (96 to 99 %).

Physical Assessment and formulation development of Dome Matrix Controlled Release tablet of Diclofenac Sodium

In the last fifteen years where have significant acceleration in drug delivery research. In the early days of controlled release, development of pharmaceutical formulations was more idealized, with emphasis on the attainment of the illusive “zero-order release behavior”. When analyzing the swelling and release behavior of the Dome Matrix systems, it was demonstrated that the swelling behavior of the curved surfaces of the matrices strongly affected the drug release kinetics. The controlled release Dome matrix tablets containing Diclofenac sodium were prepared using a wet granulation process and polymers used xanthan gum, HPMC and Eudragit. Two different formulations were prepared; in first formulation the ratio was kept 60% active ingredient and 40% polymers subsequently in 2nd formulation 55% active ingredient 45% polymers. Precompression test angle of repose, Hausner’s ratio, Bulk Density, Tapped Density, Car’s Index were checked according to the specified standard procedure. All Physical Characteristics of dome tablets were analyzed. Drug release pattern was also analyzed by using USP apparatus II paddle method. The hardness, weight fluctuation, thickness, friability, drug content homogeneity, and in-vitro dissolution investigations of the manufactured controlled release tablets. All were examined and found within acceptable range. The F1 and F2 formulations performed well in tests and had a continuous drug release. The findings of this study showed that a polymer could be successfully used to formulate Diclofenac sodium Dome matrix tablets. The drug release was extended for 8 to 12 hours in all formulations using a drug to polymer ratio of 60:40, 55:45. The formulations are proved to have efficient drug release time. Keywords: Diclofenac sodium, Dome Matrix, Eudragit, Control release, Xanthan gum.

Antibiotic impregnation and nanocoating of external ventricular drainage catheters for antibacterial applications: Evaluation of in vitro studies and molecular docking.

The most suitable method to treat hydrocephalus disease is to insert a shunt catheter that drains the cerebral spinal fluid (CSF); however, shunt implantation is often associated with various bacterial infections. In this study, antibiotic-loaded nanospheres were prepared using the solvent evaporation technique and coated on an antibiotic-impregnated shunt surface to promote shunt antibacterial properties. Clindamycin (CDM) and rifampicin (RIF) were in combination loaded in a single nanosphere, whereas trimethoprim (TMP) was loaded individually in triblock copolymers [(d,l-lactide-random-ε-caprolactone)-block-poly(ethylene glycol)-block-(d,l-lactide-random-ε-caprolactone)] (PLEC). The drug-loading content, encapsulation efficiency, yield, size, and zeta potential of the antibiotic-loaded nanospheres were measured. The results showed that the drug-loading content of clindamycin- and rifampicin-loaded nanospheres (CDM/RIF-NPs) was approximately 3% and 8%, respectively, at a drug to polymer ratio of 1:2. In addition, trimethoprim-loaded nanospheres (TMP-NPs) showed nearly 7% drug loading at equal drug and polymer ratios. The amount of drug release was determined before and after the coating of nanospheres on the shunt surface. In addition, in silico molecular docking studies indicated the good chemical interaction of these antibiotics with PLEC, and the results were consistent with those of impregnation studies. Antibacterial tests of coated external ventricular drainage showed antibacterial activity for up to 21 days.

Determination of the physical and mechanical indicators of the polymer base and the optimal method of introducing active pharmaceutical ingredients into the base composition

Treatment of wounds and wound infection remains an urgent medical problem today, especially in conditions of constant hostilities. Hydrogel bandages are quite effective means for local treatment of wounds, which are able to have a complex therapeutic effect and do not require frequent replacement in the process of medical supply to military personnel. Taking into account the relevance of this topic, our research is aimed at developing a hydrogel bandage with lidocaine hydrochloride, ceftriaxone and metronidazole. Aim. To study the physical and mechanical parameters of the polymer base and determine the optimal method for introducing active pharmaceutical ingredients (APIs) into the base composition. Materials and methods. The study materials were APIs (lidocaine hydrochloride, ceftriaxone, metronidazole) and excipients. Physical and mechanical research methods were used in the work. Results and discussion. In order to develop the optimal technology for obtaining the polymer mass and determining technological indicators, we studied the indicators of physical and mechanical properties. Indicators of breaking force and relative elongation depend on such technological characteristics as homogeneity, uniformity of application on the substrate, the absence of air bubbles. It was found that the higher the physical and mechanical parameters, the higher the quality of the polymer mass applied to the substrate. Therefore, after obtaining a homogeneous mass it is necessary to deaerate air bubbles by centrifugation (No. 1-5) at 3000 rpm for 5-10 min. During the study of the ease of application of the polymer mass on the polyethylene terephthalate substrate, it was found that the drying process was affected by the thickness of the layer. It was proven that samples No. 1-5 had a uniform, adhesive layer and could be used for further research. The main technological indicators were the layer thickness of 0.40 mm, the centrifugation time of 5-10 min at 3000 rpm, homogeneity (mixing for 15 min at 36 rpm, an anchor stirrer). It was experimentally found that to obtain a layer thickness of 0.40 mm, it was necessary to apply 0.03 g of the sample per 1 cm2 of the substrate. We proved that polymers in the concentration of 10 % provided the optimal technological indicators. To confirm this, the dependence of the viscosity of the forming solution on the concentration / ratio of polymers was studied. We found that the technological indicators of homogeneity and uniformity directly affected the quality of the resulting product. Taking into account the fact that it was possible to introduce poorly soluble substances into the composition of model samples we conducted an experiment on their sedimentation in a polymer solution. It was found that APIs introduced into the polymer solution had different values of the sedimentation rate (time), which was probably related to the degree of solubility. In addition, the polymer concentration in the forming solutions also affected the sedimentation rate of API. The higher the viscosity, the slower the API particles settled. Conclusions. It has been found in the course of the study that satisfactory indicators of physical and mechanical parameters can ensure the quality of the polymer mass production technology as the base for choosing a polymer coating for obtaining a hydrogel with anesthetic, antibacterial, and antimicrobial effects. The main technological indicators determined are the layer thickness (0.40 mm), the centrifugation time (5-10 min at 3000 rpm), homogeneity (mixing for 15 min at 36 rpm, anchor stirrer). The results obtained will be used to develop the composition and the manufacturing technology for a pharmaceutical composition with lidocaine hydrochloride, ceftriaxone and metronidazole.

A Single Injection with Sustained-Release Microspheres and a Prime-Boost Injection of Bovine Serum Albumin Elicit the Same IgG Antibody Response in Mice

Although vaccination is still considered to be the cornerstone of public health care, the increase in vaccination coverage has stagnated for many diseases. Most of these vaccines require two or three doses to be administered across several months or years. Single-injection vaccine formulations are an effective method to overcome the logistical barrier to immunization that is posed by these multiple-injection schedules. Here, we developed subcutaneously (s.c.) injectable microspheres with a sustained release of the model antigen bovine serum albumin (BSA). The microspheres were composed of blends of two novel biodegradable multi-block copolymers consisting of amorphous, hydrophilic poly(ε-caprolactone)-poly(ethylene glycol)-poly(ε-caprolactone) (PCL-PEG-PCL) blocks and semi-crystalline poly(dioxanone) (PDO) blocks of different block sizes. In vitro studies demonstrated that the release of BSA could be tailored over a period of approximately four to nine weeks by changing the blend ratio of both polymers. Moreover, it was found that BSA remained structurally intact during release. Microspheres exhibiting sustained release of BSA for six weeks were selected for the in vivo study in mice. The induced BSA-specific IgG antibody titers increased up to four weeks after administration and were of the same magnitude as found in mice that received a priming and a booster dose of BSA in phosphate-buffered saline (PBS). Determination of the BSA concentration in plasma showed that in vivo release probably took place up to at least four weeks, although plasma concentrations peaked already one week after administration. The sustained-release microspheres might be a viable alternative to the conventional prime-boost immunization schedule, but a clinically relevant antigen should be incorporated to assess the full potential of these microspheres in practice.

The effects of amino groups and open metal sites of MOFs on polymer-based electrolytes for all-solid-state lithium metal batteries

Metal-organic frameworks (MOFs) are becoming more and more popular as the fillers in polymer electrolytes in recent years. In this study, a series of MOFs (NH2-MIL-101(Fe), MIL-101(Fe), activated NH2-MIL-101(Fe) and activated MIL-101(Fe)) were synthesized and added to PEO-based solid composite electrolytes (SCEs). Furthermore, the role of the —NH2 groups and open metal sites (OMSs) were both examined. Different ratios of MOFs vs polymers were also studied by the electrochemical characterizations. At last, we successfully designed a novel solid composite electrolyte containing activated NH2-MIL-101(Fe), PEO, LiTFSI and PVDF for the high-performance all-solid-state lithium-metal batteries. This work might provide new insight to understand the interactions between polymers and functional groups or OMSs of MOFs better.

Mechanical Performance Evaluation of Repair Materials Suitable for Mechanical Pressurizing Equipment for Cross-Sectional Repair of Concrete Box Structures

This study entailed performance tests to confirm the bond performance of the proposed new repair material and the pressurization effect of the developed mechanical pressurizing equipment. The physical property changes of the new repair material were reviewed by varying the mixing ratio of high aluminate cement (HAC)-mixed mortar. Strength tests were performed according to the mixing ratios of polymer and silica fume to improve the bond performance. To improve water retention, the mixing ratios of the cellulose and nylon fibers were adjusted, and the change in water retention was measured. The proposed repair material mixing ratio yielded the best performance when pressure was applied to the repair surface. Comparing the existing repair materials and the new repair material prepared by adjusting the ratios of HAC-mixed mortar, cellulose fiber, redispersible powder resin, and other factors confirmed that the new repair material has a high bond strength.

Solubility Enhancement of Atorvastatin Tablets by Solid Dispersions Using Fenugreek Seed Mucilage

Fenugreek seed mucilage (FSM) is isolated from the seeds of Trigonella Foenum-graecum, commonly known as Fenugreek, which is herbaceous plant. Fenugreek seeds contain high percentage of mucilage, which does not dissolve in water, but swell up and become slick when exposed to fluids. Atorvastatin is one of the HMG-CoA reductase inhibitors (statins), which are lipid-lowering medications used in the primary and secondary prevention of coronary heart disease. Atorvastatin is poorly absorbed orally, its oral bioavailability is very low (about14%) because it is very slightly soluble in distilled water and pH 7.4 phosphate buffer, which would limit its clinical application. The objective of this study is to enhance atorvastatin solubility in order to increase its bioavailability by the formulation of solid dispersion using fenugreek seed mucilage. Mucilage was extracted from the seed and evaluated for flow properties, pH value, FTIR spectroscopy and percentage practical yield. Then solid dispersions with different drug to polymer ratios were prepared from fenugreek mucilage and hydroxy propyl methyl cellulose (HPMC), after that saturation solubility was tested for fenugreek seed mucilage solid dispersion (FSMSD), hydroxxy propyle methyl cellulose solid dispersion (HPMCSD) and pure drug. Tablets were prepared from solid dispersion with the highest saturation solubility, then tablets were tested and evaluated. The tablets showed satisfactory physicochemical properties as 1.77%RSD in tablet weight variation, 1 min disintegration time, 5.24±0.457 Hardness and 89% drug release in 45 min. it is concluded that FSM is a promising excipient that can be used in dosage forms formulation to enhance solubility of low soluble drugs.

Structural Insights into Polymer-Bounded Lipid Nanodiscs.

Membrane proteins are an essential part of signaling and transport processes and are targeted by multiple drugs. To isolate and investigate them in their native state, polymer-bounded nanodiscs have become valuable tools. In this study, we investigate the lipid model system dimyristoyl-phosphocholine (DMPC) with the nanodisc-forming copolymers styrene maleic acid (SMA) and diisobutylene maleic acid (DIBMA). Using small-angle X-ray scattering (SAXS) and dynamic light scattering (DLS), we studied the influence of polymer concentration and temperature on the nanodisc structure. In Tris buffer, the size of nanodiscs formed with SMA is smaller compared to DIBMA at the same polymer ratio. In both cases, the size decreases monotonically with increasing polymer concentration, and this effect is more pronounced when using SMA. Measurements at temperatures (T) between 5 and 30 °C in phosphate buffer showed an incomplete solubilization at high T even at polymer/lipid ratios above that required for complete lipid solubilization. For DIBMA, the nanodiscs developed at lower temperatures are stable and the net repulsion increases, while for SMA, the individual nanodiscs possess smaller sizes and are less affected by T. However, using DLS, one can observe SMA agglomerates at low T. Interestingly, for both polymers, no drastic changes of the observable parameters (radius and bilayer thickness) are seen upon cooling, which would indicate a sharp (first-order) phase transition from liquid-crystalline to gel, but only gradual changes. Hence, we conclude that the transition from a gel toward a liquid-crystalline lipid phase proceeds over a broad T-range compared to a continuous lipid bilayer. These results can pave the way toward the development of better protocols for studying membrane proteins stabilized in this type of membrane mimics.

Resveratrol-Loaded Microsponge Gel for Wound Healing: In Vitro and In Vivo Characterization.

The study was aimed to formulate resveratrol (RSV) loaded microsponges to deliver drug at the wound site and incorporate it in the Moringa oleifera Lam. (Moringaceae) gel base to provide an appropriate moist environment for wound management. RSV, a stilbenoid that activates sirtuins and cell-signaling regulators involved in the process of wound healing. Microsponges were prepared by oil in oil emulsion solvent diffusion method by optimizing the independent variables; drug: polymer ratio and volume of internal phase solvent and their effects on entrapment efficiency and particle size. Formulation batches were evaluated for drug content, production yield, entrapment efficiency, and in vitro drug release. The microsponges were further incorporated into M. oleifera gum gel, which was then evaluated for spreadability, viscosity, ex vivo diffusion study and in vivo studies using an excision wound model in rats. Scanning electron microscopy revealed spherical and porous nature of the microsponges in vitro-release study of the optimized batch of RSV microsponges showed 80.88% drug release within 8 h. Differential scanning calorimetry results revealed no drug and polymer interaction during the formation of microsponges. An ex vivo diffusion study through goat skin revealed sustained release of RSV through porous microsponges embedded in the gel base at the wound site. An in vivo study performed using an excision wound model showed wound healing and closure within day 8. Histopathology showed increased re-epithelization and reduced ulceration in RSV microsponge gel-treated group compared with sham operated. RSV microsponge gel delivered the drug at the wound site and the gel base provided a moist environment and influenced cell adhesion, thereby promoting faster wound healing.

TARTESSUS: A Customized Electrospun Drug Delivery System Loaded with Irinotecan for Local and Sustained Chemotherapy Release in Pancreatic Cancer.

Post-surgical chemotherapy in pancreatic cancer has notorious side effects due to the high dose required. Multiple devices have been designed to tackle this aspect and achieve a delayed drug release. This study aimed to explore the controlled and sustained local delivery of a reduced drug dose from an irinotecan-loaded electrospun nanofiber membrane (named TARTESSUS) that can be placed on the patients' tissue after tumor resection surgery. The drug delivery system formulation was made of polycaprolactone (PCL). The mechanical properties and the release kinetics of the drug were adjusted by the electrospinning parameters and by the polymer ratio between 10 w.t.% and 14 w.t.% of PCL in formic acid:acetic acid:chloroform (47.5:47.5:5). The irinotecan release analysis was performed and three different release periods were obtained, depending on the concentration of the polymer in the dissolution. The TARTESSUS device was tested in 2D and 3D cell cultures and it demonstrated a decrease in cell viability in 2D culture between 72 h and day 7 from the start of treatment. In 3D culture, a decrease in viability was seen between 72 h, day 7 (p < 0.001), day 10 (p < 0.001), 14 (p < 0.001), and day 17 (p = 0.003) as well as a decrease in proliferation between 72 h and day 10 (p = 0.030) and a reduction in spheroid size during days 10 (p = 0.001), 14 (p < 0.001), and 17 (p < 0.001). In conclusion, TARTESSUS showed a successful encapsulation of a chemotherapeutic drug and a sustained and delayed release with an adjustable releasing period to optimize the therapeutic effect in pancreatic cancer treatment.

Biomaterials Based on Chitosan and Polyvinyl Alcohol as a Drug Delivery System with Wound-Healing Effects

The excellent biological properties of chitosan (CS) together with the increased oxygen permeability of polyvinyl alcohol (PVA) were the prerequisites for the creation of a wound healing dressing that would also function as a system for L-arginine (L-arg) and caffeine (Caff) delivery. Using the freezing/thawing method, 12 hydrogels were obtained in PVA:CS polymer ratios of 90:10, 75:25, and 60:40, and all were loaded with L-arg, Caff, and the mixture of L-arg and Caff, respectively. Afterwards, an inorganic material (zeolite-Z) was added to the best polymeric ratio (75:25) and loaded with active substances. The interactions between the constituents of the hydrogels were analyzed by FTIR spectroscopy, the uniformity of the network was highlighted by the SEM technique, and the dynamic water vapor sorption capacity was evaluated. In the presence of the inorganic material, the release profile of the active substances is delayed, and in vitro permeation kinetics proves that the equilibrium state is not reached even after four hours. The synergy of the constituents in the polymer network recommends that they be used in medical applications, such as wound healing dressings.

Application of Molecularly Imprinted Electrochemical Sensor for Selective Non-Labelled Detection of Acetamiprid Insecticide in Fruits

Acetamiprid (ACP) is a widely used systemic insecticide as a replacement for organophosphorus compounds to control sucking-type insects on leafy vegetables, fruits, and tea trees. In this work, bulk polymerized molecularly imprinted polymer was developed using ACP as template, 4-Vinyl pyridine as monomer and ethylene glycol dimethyl acrylate (EGDMA) as cross-linker in presence of acetone as porogen. The polymers were then tested as a template recognition modifiers for carbon paste electrode in cooperation with multiwalled carbon nanotubes as a signal enhancer. The optimum response towards ACP was attained on using 10% of polymer ratio (1: 3: 40) and 5% MW-CNT in the electrode composition at pH 6.2 of 0.1 phosphate buffer as supporting electrolyte. The developed electrode was morphologically and electrochemically characterized and was found to show a linear response for differential pulse voltammetry of 1 × 10−12–5 × 10−6 M equivalent to 0.222–111.3 ×104 ng l−1 with limits of detection and quantification of 7.35 × 10−3 and 0.022 ng l−1, respectively. The electrode was efficiently applied for ACP detection in its pure solutions, commercial insecticide formulation and spiked apple, tomato, and watermelon samples with recoveries from 95.55%-101.66% indicating its efficiency for application in regulatory units for hazardous food contaminants.

Casein-Based Nanoparticles: A Potential Tool for the Delivery of Daunorubicin in Acute Lymphocytic Leukemia

The aim of this study was to develop casein-based nanoscale carriers as a potential delivery system for daunorubicin, as a pH-responsive targeting tool for acute lymphocytic leukemia. A coacervation technique followed by nano spray-drying was used for the preparation of drug-loaded casein nanoparticles. Four batches of drug-loaded formulations were developed at varied drug-polymer ratios using a simple coacervation technique followed by spray-drying. They were further characterized using scanning electron microscopy, dynamic light scattering, FTIR spectroscopy, XRD diffractometry, and differential scanning calorimetry. Drug release was investigated in different media (pH 5 and 7.4). The cytotoxicity of the daunorubicin-loaded nanoparticles was compared to that of the pure drug. The influence of the polymer-to-drug ratio on the nanoparticles' properties such as their particle size, surface morphology, production yield, drug loading, entrapment efficiency, and drug release behavior was studied. Furthermore, the cytotoxicity of the drug-loaded nanoparticles was investigated confirming their potential as carriers for daunorubicin delivery.