Hydroxypropyl Methylcellulose Concentration Research Articles

Hydroxypropyl Methylcellulose as Hydrogel Matrix and Citric Acid-Locust Bean Gum as Negative Matrix for Controlled Release Tablet.

Purpose: This study aimed at determining the optimum concentration of hydroxypropyl methylcellulose (HPMC) as hydrogel matrix and citric acid-locust bean gum (CA-LBG) as negative matrix for controlled release tablet formulation. In addition, the study was to determine the effect of CA-LBG and HPMC. CA-LBG accelerates the disintegration of tablets into granules so that the HPMC granule matrix swells immediately and controls drug release. The advantage of this method is that the tablets do not produce large HPMC gel lumps without drug (ghost matrix) but form HPMC gel granules, which can be rapidly degraded after all of the drug is released. Methods : The experiment followed the simplex lattice design to obtain the optimum tablet formula with CA-LBG and HPMC concentrations as optimization factors. Tablet production by the wet granulation method and ketoprofen is the model of the active ingredient. The kinetics of ketoprofen release was studied using several models. Results : Based on the coefficients of each polynomial equation that HPMC and CA-LBG increased the value of angle of repose (29.91:27.87), tap index (18.99:18.77), hardness (13.60:13.32), friability (0.41:0.73), and release of ketoprofen (52.48:99.44). Interaction of HPMC and CA-LBG increased the value of angle of repose (3.25), tap index (5.64), and hardness (2.42). Interaction of HPMC and CA-LBG too decreased the friability value (-1.10) and release of ketoprofen (-26.36). The Higuchi, Korsmeyer-Peppas, and Hixson-Crowell model is the kinetics of eight experimental tablet formulas. Conclusions : The optimum concentrations of HPMC and CA-LBG for controlled release tablets are 32.97 and 17.03%, respectively. HPMC, CA-LBG, and a combination of both affect the physical quality of tablet and tablet mass. CA-LBG is a new excipient candidate that can control drug release from tablets by the matrix disintegration mechanism on the tablet.

Fabrication of Gastro-Floating Famotidine Tablets: Hydroxypropyl Methylcellulose-Based Semisolid Extrusion 3D Printing.

Semisolid extrusion (SSE) three-dimensional (3D) printing uses drug-loaded paste for the printing process, which is capable of constructing intricate 3D structures. This research presents a unique method for fabricating gastro-floating tablets (GFT) using SSE. Paste-loaded famotidine with a matrix made of hydroxypropyl methylcellulose (HPMC) were prepared. Nine 3D printed tablets were developed with different HPMC concentrations and infill percentages and evaluated to determine their physicochemical properties, content uniformity, dissolution, and floating duration. The crystallinity of the drug remained unchanged throughout the process. Dissolution profiles demonstrated the correlation between the HPMC concentration/infill percentage and drug release behavior over 10 h. All the fabricated GFTs could float for 10 h and the Korsmeyer-Peppas model described the dissolution kinetics as combination of non-Fickian or anomalous transport mechanisms. The results of this study provided insight into the predictability of SSE 3D printability, which uses hydro-alcoholic gel-API blend materials for GFTs by controlling traditional pharmaceutical excipients and infill percentages. SSE 3D printing could be an effective blueprint for producing controlled-release GFTs, with the additional benefits of simplicity and versatility over conventional methods.

Preparation and investigation of electrical conductivity of silver nanoparticle films on the paper substrate

This paper reported the preparation of silver nanoparticles (Ag NPs) by the chemical protection-reduction method. This process was performed in an aqueous phase with a mixture consisting of silver nitrate (AgNO3), hydroxypropyl methylcellulose (HPMC), sodium borohydride (NaBH4), and hydrazine (H2N-NH2). The prepared Ag NPs were characterized by transmission electron microscope (TEM) and ultraviolet-visible (UV-Vis) spectroscopy. The TEM images indicated that Ag NPs had high purity with the size of 20‒50 nm. The Ag NPs solution strongly absorbed around 420 nm and displayed brown color under visible light. The stability of the Ag NPs solution was maintained after 60 days of storage. The conductivity of the Ag NPs solution depended on the initial concentration of AgNO3, HPMC content, type of reducing agent, pH environment, and also the order of using reducing agents in the prepared process. Next, the Ag NPs solution was coated to form a film on the paper substrate. The thickness of the obtained film was about 49.2 µm according to the analysis results from the Leica 2500 DM microscope and its conductivity was investigated by the four-point probe method. The film could conduct the electricity and light up LEDs when using a 9 V DC power source. The obtained results demonstrated that the prepared Ag NPs would have a potential application as conductive inks in electrical plastic devices.

Pilot-scale binder jet 3D printing of sustained release solid dosage forms

The additive nature and versatility of 3D printing show great promise in the rapid prototyping of solid dosage forms for clinical trials and mass customization for personalized medicine applications. This paper reports the formulation and process development of sustained release solid dosage forms, termed “printlets”, using a pilot-scale binder jetting (BJT) 3D printer and acetaminophen (APAP) as the model drug. With the inclusion of hydroxypropyl methylcellulose (HPMC) as a release retardant polymer in the print powder, the drug release time of APAP increased considerably from minutes to hours. However, given the swelling propensity of HPMC, a thicker layer of powder must be laid down during printing to avoid any shape distortion of the printlets. For a fixed print volume, the level of binder saturation (i.e., ratio between the liquid binder and powder in the as-printed sample) is inversely proportional to the thickness of the spread powder layer. An increase in the spread powder layer inadvertently resulted in a lower level of binder saturation and consequently weaker printlets. By increasing the level of binder saturation with jetting from more print heads, the mechanical strength of printlets containing 18% HPMC was successfully restored. The resultant printlets have a drug release time of 3.5 h and a breaking force of 12.5 kgf that is comparable to the fast-disintegrating printlets containing no HPMC and surpasses manually pressed tablets with the same HPMC content.

Development of Besifloxacin HCL Loaded Ocular İn Situ Gels; In Vitro Characterization Study

Objective: The aim of this study is to develop in situ gel formulations containing besifloxacin hydrochloride are heat triggered, which are prepared by using different poloxomer and derivatives different polymers that will change the gelling temperature to increase corneal contact time, regulate drug release, improve ocular bioavailability and increase patient compliance increase mucoadhesion.
 Material and Method: Various concentrations of poloxamer 188 (P188) and poloxamer 407 (P407) were used to create the in situ forming gels. To increase the gel's capacity for bioadhesion, mucoadhesives such hydroxypropylmethyl cellulose (HPMC) or hydroxyethyl cellulose (HEC) were included in the formulations. Drug release in vitro, sol-gel transition temperature, rheological behavior, pH, clarity, and mucoadhesion force were all assessed for the produced formulations. 
 Result and Discussion: The developed formulations' gelation temperatures ranged from 29 to 35°C. The preparations' viscosity and mucoadhesion force increased with increasing P407, HPMC, and HEC concentrations. Besifloxacin HCl forms in situ gel formulas with K1, K2, K3, and K6 suited for mucoadhesion characteristics, gelation temperature, and viscosity. These formulations exhibit pseudoplastic flow. Increasing polymer concentrations resulted in a reduction in the burst release of the formulations. However, at the end of 6 hours, drug release was finished in all formulations. The results show that in situ gels containing P407 and P188 show promise for besifloxacin HCl application

Synthesis of antibacterial hydroxypropyl methylcellulose and silver nanoparticle biocomposites via solution plasma using silver electrodes

The biocomposites of hydroxypropyl methylcellulose (HPMC)/silver nanoparticles (AgNPs) were synthesized using the solution plasma process (SPP). HPMC/AgNPs were synthesized in 1–5 % HPMC solutions using silver electrodes. UV–Vis spectroscopy showed a peak near 400 nm and the peak increased as the concentration of HPMC and discharge time increased. FTIR analysis indicated no change in the chemical structure of the HPMC based biocomposites. Spherical shaped AgNPs with size ranges about 2–18 nm and well dispersed in the porous HPMC matrices with fringed edges were observed by TEM and SEM/EDS analyses. The synthesized biocomposites were found to be thermo-stable by TGA analysis. The inhibition zones of bacterial growth formed by the HPMC/AgNPs biocomposites were in the range of 8–14.3 mm; minimal inhibition concentrations, in the range of 10–15 μg·mL−1 for Gram-negative bacteria; 25–30 μg·mL−1 for Gram-positive bacteria. The biocomposites were non-toxic to the HEK293 cells up to 125 μg·mL−1. The results indicated that the synthesis of antibacterial agents in the HPMC matrix using silver electrodes via SPP would be an efficient and safe way for the development of biopolymer based antimicrobials and wound healing biomaterials.

Fabrication and characterization of super-hydrophilic poly (ε-caprolactone)/hydroxypropyl methylcellulose (HPMC) based composite electrospun membranes for tissue engineering applications.

Tissue engineering (TE) employs scaffolds as a structural support for initially seeding of cells followed by development of new tissues. Electrospun scaffolds generally function as a template of native extracellular matrix (ECM). The chemical composition of the scaffold and its surface morphology strongly influence the interaction between various cell types and materials. In this work, PCL and PCL/HPMC-based composite membranes with varying concentrations of HPMC (20-30% by weight) were fabricated using electrospinning technique. The membranes were evaluated for their surface, physio-chemical and biological properties. It was observed probably for the first time that blending of HPMC with PCL produced super-hydrophilic scaffolds. DSC studies confirmed the semi- crystalline nature of HPMC. PCL/HPMC composite scaffolds are found biocompatible from cytotoxicity assay. From the cell culture studies (apoptosis), PCL/HPMC composite scaffolds did not inhibit the adhesion of L929 cells due to their super-hydrophilic nature. The cell adhesion and spreading varied with HPMC concentration. PCL/HPMC (70/30) membranes showed highest cell adhesion among others due to its porous structure.

Evaluation of mechanical and thermal properties of carrageenan/hydroxypropyl methyl cellulose hard capsule

AbstractThe inherent source of gelatin used for commercial hard capsules causes a surging demand for vegetarian capsules. In this work, carrageenan is utilized in preparing hard capsules to meet consumer preferences. Hydroxypropyl methylcellulose (HPMC) was incorporated as a reinforcing agent to improve the low mechanical properties of hard capsules made of carrageenan. The HPMC concentration was manipulated from 0.2 to 1.0 w/v% in the carrageenan matrix. The increasing concentration of HPMC exerts significant effects on the tensile strength and elongation at break, with an improvement of 59.1% and 46.9%, respectively, at the optimized HPMC concentration of 0.8 w/v%. The loop strength of the capsule is also increased by 56.4% with decreasing moisture content. The downfield movement from around 3.20 ppm of the carrageenan proton to 3.33 ppm in the proton nuclear magnetic resonanance ( 1H‐NMR) spectrum suggests the formation of intermolecular hydrogen bonding between carrageenan and HPMC, which correlates to the results of Fourier‐transform infrared spectroscopy (FTIR) and zeta potential. The glass transition temperature of the film was increased from 37.8 to 65.3°C, showing an upgrade in thermal stability. The film possesses a major mass loss with an activation energy of 64.7 kJ/mol with an increment of 43.4% compared to the control carrageenan. These findings support the conclusion that HPMC enhanced the mechanical properties and thermal stability of the carrageenan film, and the comprehensive analysis of the molecular interaction and decomposition kinetics subsequently may expand the application fields of the carrageenan‐HPMC hard capsule as an alternative to gelatin in the future.

Formulation and In-vitro Antibacterial Activity of Gel containing Ethanolic extract of Purple Sweet Potato Leaves (Ipomoea batatas (L.) Loaded Poly Lactic Co-Glycolic Acid Submicroparticles against Staphylococcus aureus

Staphylococcus aureus has been resistant to various antibiotics including erythromycin, clindamycin, penicillin, trimethoprim-sulfamethoxazole, tetracyclines, chloramphenicol, and piperacillin-tazobactam so that an alternative treatment is needed. The purple sweet potato leaves (Ipomoea batatas (L.) Poir) contain flavonoid compounds that have antibacterial activity by inhibiting nucleic acid, protein synthesis, cell membrane, and energy metabolism in bacteria. In this study, ethanolic extract of purple sweet potato leaves is loaded to poly lactic-co-glycolic acid submicroparticles to increase the stability of flavonoids and the antibacterial effect. Submicroparticle gel was prepared with various concentrations of hydroxypropyl methylcellulose ie F1, F2, and F3 respectively 3%, 5%, and 7%. The antibacterial activity of submicroparticles gel compared with a gel containing extracts without submicroparticle and erythromycin gel as a positive control. Phytochemical test results that the ethanolic extract of purple sweet potato leaves contains flavonoids. Based on the research results, the best formula was F1(3%) with pH, homogeneity, viscosity, dispersibility, adhesion, and washability, respectively 7.4±0.0361; homogeneous; 8358.9±228.1391 cps; 4.2667±0.3005cm; 45.333±2.5166 seconds; 11.6667±1.5275mL. F1 was also shown to have strong antibacterial activity with an inhibition zone value of 13.67±4.04mm.

Development of Saturated Fat Replacers: Conventional and Nano-Emulsions Stabilised by Lecithin and Hydroxylpropyl Methylcellulose.

The combination of two emulsifiers, lecithin and hydroxypropyl methylcellulose (HPMC), into emulsions is an interesting strategy to design fat replacers in food matrices. The objective of this study was to investigate the effect of HPMC type and concentration on the formation, stability, and microstructure of conventional emulsions and nanoemulsions. Two different types of HPMC with low and high content of methyl and hydroxypropyl groups (HPMC-L and HPMC-H) were evaluated. The results showed that the molecular structure and concentration of HPMC play a major role in the viscoelastic behaviour, the gelation temperature, and the strength of gel formed. The firmness and work of shear of HPMC solutions increased significantly (p < 0.05) with increasing concentration. HPMC-L illustrated a more stable gel structure than the HPMC-H solution. Nanoemulsions showed lower moduli values, firmness, and work of shear than conventional emulsions due to the influence of high-pressure homogenization. A combination of lecithin and HPMC improved the physical and lipid oxidative stability of the emulsions, presenting a lower creaming index and thiobarbituric acid reactive substances (TBARS). In conclusion, HPMC-L at 2% w/w could be a suitable type and concentration combined with lecithin to formulate a saturated fat replacer that could mimic butter technological performance during food manufacturing operations.

Tailoring of Rosuvastatin Calcium and Atenolol Bilayer Tablets for the Management of Hyperlipidemia Associated with Hypertension: A Preclinical Study

Hyperlipidemia is still the leading cause of heart disease in patients with hypertension. The purpose of this study is to make rosuvastatin calcium (ROS) and atenolol (AT) bilayer tablets to treat coexisting dyslipidemia and hypertension with a single product. ROS was chosen for the immediate-release layer of the constructed tablets, whereas AT was chosen for the sustained-release layer. The solid dispersion of ROS with sorbitol (1:3 w/w) was utilized in the immediate-release layer while hydroxypropyl methylcellulose (HPMC), ethylcellulose (EC), and sodium bicarbonate were incorporated into the floating sustained-release layer. The concentrations of HPMC and EC were optimized by employing 32 full factorial designs to sustain AT release. The bilayer tablets were prepared by the direct compression method. The immediate-release layer revealed that 92.34 ± 2.27% of ROS was released within 60 min at a pH of 1.2. The second sustained-release layer of the bilayer tablets exhibited delayed release of AT (96.65 ± 3.36% within 12 h) under the same conditions. The release of ROS and AT from the prepared tablets was found to obey the non-Fickian diffusion and mixed models (zero-order, Higuchi and Korsmeyer–Peppas), respectively. Preclinical studies using rabbit models investigated the impact of ROS/AT tablets on lipid profiles and blood pressure. A high-fat diet was used to induce obesity in rabbits. Bilayer ROS/AT tablets had a remarkable effect on decreasing the lipid profiles, slowing weight gain, and lowering blood pressure to normal levels when compared to the control group.

Transglutaminase and hydroxypropyl methyl cellulose enhance mechanical properties of whey protein concentrate film

SummaryWhey protein and cellulose derivatives are abundant and renewable raw materials that provide an environmentally friendly alternative to fossil fuel sources used for food packaging. A novel biodegradable composite film comprising whey protein concentrates (WPC) aqueous solutions (10%, w/v) with different concentrations of Hydroxypropyl methylcellulose (HPMC) (0, 1, 2, 3, 4 and 5 wt% of WPC) was prepared in the present study. The effect of transglutaminase (TG) on the functional properties of the film was investigated. SDS‐PAGE profiles indicated that TG modulated the formation of intermolecular cross‐linking of WPC. FT‐IR results showed that HPMC modified the mechanical properties of WPC. Incorporation of HPMC decreased the transparency and improved the tensile strength and extensibility of the film. TG addition led to a significant enhancement of the mechanical properties of the film. These findings indicated that TG promoted the formation of WPC‐HPMC composite film with improved mechanical properties.

Hydroxypropyl methylcellulose (HPMC) reduces the hardening of fructose-containing and maltitol-containing high-protein nutrition bars during storage

In this study, high-protein nutrition bars (HPNBs) were prepared using sodium caseinate and either fructose or maltitol as raw materials. The effects of the incorporation of hydroxypropyl methylcellulose (HPMC) on the hardness and physicochemical changes of HPNBs during storage were evaluated. Both HPNB systems containing HPMC exhibited significantly lower hardness than the control HPNBs (no HPMC) during storage, and the change in hardness was dependent on the concentration of HPMC added. The incorporation of 2% HPMC reduced the hardness of the fructose-containing and maltitol-contianing HPNBs by 44.83% and 27.89%, respectively, after 35 days of storage. The addition of HPMC inhibited Maillard reactions within the fructose-containing HPNBs, which exhibited little changes in the total color and composition of free amines. HPMC also significantly mitigated the increase in the insoluble protein content and the transformation of β-turn to β-sheet in proteins that were observed in both HPNB systems during storage. Scanning electron microscopy also confirmed that the texture of the HPNB containing HPMC changed less during storage compared to the controls. These results indicated that HPMC could be used as an inhibitor to reduce the extent of Maillard reactions and protein aggregation during food storage.

The Feasibility of Hydroxypropyl Methylcellulose as an Admixture for Porous Vegetarian Concrete Using Coarse Recycled Aggregates

In this paper, hydroxypropyl methylcellulose (HPMC) is used as a new additive for porous vegetarian concrete (PVC) to improve its void structure and strength. The effect of the HPMC on the fluidity of the mortar was first investigated by a viscosity test. Then the cement hydration process was determined for analyzing the effect of the HPMC on the strength and durability of the hardened PVC. Subsequently, experiments to investigate the mass transport and compressive strength characteristics, as well as the vegetarian properties, of the concrete were carried out. The results show that the bonding forces between the recycled aggregates and packing layer are elevated by viscosity improvement. The viscocity and flowability are significantly related to the dosage of HPMC from 0.0‰ to 0.3‰. The harden time is also delayed while the content of HPMC increases.The segregation phenomenon caused by the recycled aggregate powder in porous concrete could also be relieved by adding HPMC. The durability of PVC in the wetting–drying cyclic test is significantly improved by incorporating HPMC. The results of the vegetarian test also prove that, with HPMC mixing, sufficient space would be created in porous concrete, which is more suitable for plant growth due to a large number of existing pore channels.

Effect of soybean protein isolate-pectin composite nanoparticles and hydroxypropyl methyl cellulose on the formation, stabilization and lipidolysis of food-grade emulsions

The formation and stabilization mechanism as well as digestion characteristics of food-grade emulsions prepared by the SPNPs-HPMC mixed systems (a combination of soybean protein isolate-pectin composite nanoparticles (SPNPs) and hydroxypropyl methylcellulose (HPMC)) were investigated. Then, it was found that the SPNPs-HPMC mixed systems could not only enhance the stability of the emulsion, but also make it have a satisfactory lipidolys is efficiency. During the formation and stabilization of the emulsion, HPMC was adsorbed in the early stage of emulsion formation, while SPNPs needed a longer adsorption time. When the HPMC concentration was 0.25–0.5 wt%, HPMC and SPNPs co-adsorbed on the interface. When the HPMC concentration was 1–2 wt%, HPMC and SPNPs competed to adsorb on the interface, of which the adsorption HPMC was dominant. In vitro simulation of digestion, SPNPs were decomposed into substances with lower interfacial activity, and the structure and activity of HPMC were well maintained, which led them to reconstruct a new interface layer. Thus, the size distribution and surface area of the emulsion droplets were retained in a good state for the lipidolysis process. Therefore, the SPNPs-HPMC mixed systems could both enhance the stability of the emulsion and grant it a satisfactory lipidolysis efficiency.

Sustainable alginate/aloe vera composite biodegradable films reinforced with carboxymethyl cellulose and hydroxypropyl methylcellulose

AbstractBiopolymers like polysaccharides are being used to develop biodegradable and edible food packaging films. These films are environment friendly but have inferior mechanical strength as compared to conventional plastics. This study seeks to enhance the mechanical properties of alginate aloe vera composite films by the fusion of organic fibers like carboxymethyl cellulose (CMC) and hydroxypropyl methylcellulose (HPMC). CMC and HPMC were added at varying concentrations (2%–14%).Addition of both these cellulose derivatives had a positive effect on the tensile strength and elongation at break of the composite films. The tensile strength increased to a maximum value of 35.08 and 51.96 N/mm2 in CMC and HPMC films, respectively at 4% concentration of both. Increasing the fiber concentration further resulted in a decrease of tensile strength. Similar trend was observed in the flexibility of the films as the elongation at break value was maximum 5.57% and 3.21%, respectively at 4% concentration. The addition of CMC reduced the water solubility of the film. The solubility decreased to 19% at the maximum concentration of CMC. The effect of HPMC on water solubility was opposite to that of CMC. The solubility of the film increased to 86.42% at highest concentration of HPMC. CMC slowed down the biodegradation rate of the films whereas HPMC increased it.

Design and Characterization of Agarose/HPMC Buccal Films Bearing Ondansetron HCl In Vitro and In Vivo: Enhancement Using Iontophoretic and Chemical Approaches.

The study was aimed at designing and characterizing the ondansetron hydrochloride (OND) bearing agarose (AG), and hydroxypropyl methyl cellulose (HPMC) mucoadhesive buccal films employing glycerol as a plasticizer. The buccal delivery of ondansetron hydrochloride was remarkably boosted by employing physical (iontophoresis) and chemical enhancement approaches (chemical penetration enhancers). To explore the influence of different formulation components, i.e., agarose, hydroxypropyl methyl cellulose (HPMC), and glycerol on various evaluating parameters, i.e., tensile strength, swelling index, ex vivo mucoadhesion time, and subsequently on in vitro drug release, a D-optimal design was opted. A buccal film bearing OND was mounted on bovine buccal mucosa for ex vivo permeation studies and impact of chemical and physical enhancement techniques on the permeation profile was also analysed. A linear release profile was revealed in in vitro drug release of OND over 60 minutes and outcomes ascertained the direct relationship between HPMC content and in vitro drug release and inverse relationship was depicted by AG content. The FTIR and DSC thermal analysis was executed to determine the physicochemical interactions and results exposed no chemical interactions between drug and polymers. The drug (OND) appeared as tiny crystals on smooth film surface during scanning electron microscopy (SEM) analysis. A notable enhancement in permeation flux, i.e., 761.02 μg/min of OND during ex vivo permeation studies was witnessed after the application of current (0.5-1 mA) without any time lag and with enhancement ratio of 3.107. A time lag of 15 minutes, 19 minutes, and 26 minutes with permeation flux of 475.34 μg/min, 399.35 μg/min, and 244.81 μg/min was observed after chemical enhancer pretreatment with propylene glycol, Tween 80, and passive, respectively. Rabbit was employed as the experimental animal for pharmacokinetic studies (in vivo) and cats for pharmacological activity (in vivo), and the results illustrated the enhanced bioavailablity (2.88 times) in the iontophoresis animal group when compared with the rabbits of control group. Likewise, a remarkable reduction in emesis events was recorded in cats of iontophoresis group. Conclusively, the histopathological examinations on excised buccal mucosa unveiled no severe necrotic or cytopathetic outcomes of current.

Coating of fruit with an edible soybean protein isolate film doped with hydroxypropyl methyl cellulose for improved preservation

Coating a film on the surface of fruits to prolong the shelf life is an often-used method. However, wax coating is not sustainable and environmentally compatible. In this study, soybean protein isolate (SPI) and hydroxypropyl methyl cellulose (HPMC) were dissolved to form a coating solution with glycerin added as a plasticizer. The results showed that the tensile strength (TS) of the films increased from 6.52 to 20.76 MPa and the elongation at break (EAB) decreased from 68.07% to 12.67% when HPMC content increased from 0% to 20%, respectively. The intermolecular forces between the SPI and HPMC molecules made the polymers film-forming and the obtained film more continuous and stronger. The obtained film was tested on grapes and cherry tomatoes, which tightly coated with the film without any cracks. This greatly delayed their deterioration. By comparing the mass loss, total soluble solids, hardness, titratable acids, and pH values, the results showed that the coated grapes and cherry tomatoes exhibited higher freshness than the bare ones. This study fabricated an environmentally friendly coating that could prolong the shelf life of fruits, which will potentially promote the healthy development of the fruit industry.

Modulation of viscosity, microstructure and lipolysis of W/O emulsions by cellulose ethers during in vitro digestion in the dynamic and semi-dynamic gastrointestinal models

In this study, W/O emulsions incorporated with various proportions of two hydrocolloids, namely, methylcellulose (MC) and hydroxypropyl methylcellulose (HPMC), were prepared. The shear viscosity, microstructure, and lipolysis of the W/O emulsions before and during in vitro digestion in the dynamic (DIVHS) and semi-dynamic gastrointestinal models were evaluated and compared. The shear viscosity of both emulsions increased with the addition of MC and HPMC content up to a certain limit (0.5–2%), whereas it significantly decreased at a higher addition level (4%) due to the increased flocculation and coalescence in higher cellulose ethers. The HPMC emulsions (2 wt % in aqueous phases) showed higher viscosity and larger droplet size than the equivalent MC emulsions before and during simulated digestion, accompanied by the lower extent of lipolysis. These results are in line with the formation of a more compact and stronger gel structure in HPMC emulsions, which could retard lipase adsorption at the W–O interface. For both emulsions at the same concentration (40 wt%), a higher extent of free fatty acid (FFA) release was found during digestion in the dynamic system (HPMC ꞊ 62%, MC ꞊ 72%) compared to that in the semi-dynamic model (HPMC ꞊ 58%, MC ꞊ 70%). This behavior was supported by the smaller droplet size of emulsions digesta collected from the dynamic system having a larger surface area. Overall, the present study suggested that the dynamic DIVHS system was more effective in enzymatic hydrolysis of the W/O emulsions investigated than the semi-dynamic model under the current experimental conditions. This work had provided valuable insights into the modulation of the structural and digestive properties of W/O emulsions by the addition of MC and HPMC, which could be meaningful for the development of healthier emulsion-based food products (e.g., margarine and spreads) with reduced lipid digestibility.

Raman mapping-based non-destructive dissolution prediction of sustained-release tablets

In this paper, the applicability of Raman chemical imaging for the non-destructive prediction of the in vitro dissolution profile of sustained-release tablets is demonstrated for the first time. Raman chemical maps contain a plethora of information about the spatial distribution and the particle size of the components, compression force and even polymorphism. With proper data analysis techniques, this can be converted into simple numerical information which can be used as input in a machine learning model. In our work, sustained-release tablets using hydroxypropyl methylcellulose (HPMC) as matrix polymer are prepared, the concentration and particle size of this component varied between samples. Chemical maps of HPMC are converted into histograms with two different methods, an approach based on discretizing concentration values and a wavelet analysis technique. These histograms are then subjected to Principal Component Analysis, the score value of the first two principal components was found to represent HPMC content and particle size. These values are used as input in Artificial Neural Networks which are trained to predict the dissolution profile of the tablets. As a result, accurate predictions were obtained for the test tablets (the average f2 similarity value is higher than 59 with both methods). The presented methodology lays the foundations of the analysis of far more extensive datasets acquired with the emerging fast Raman imaging technology.