Addition Of Hydroxypropyl Methylcellulose Research Articles

The effect of hydroxy propyl methyl cellulose on emulsion stability and sensory properties of virgin coconut oil mayonnaise

Mayonnaise is a semi-solid emulsion made by mixing ingredients such as vegetable oil, egg yolks, and other food ingredients with or without adding food additives, such as stabilizers. This research aimed to study the effect of hydroxypropyl methylcellulose (HPMC) on the emulsion stability and sensory properties of mayonnaise made from virgin coconut oil. In this study, the treatment was the addition of HPMC, namely MV1 (0%), MV2 (2%), MV3 (3%), MV4 (4%), and MV5 (5%), into the mayonnaise formulation. The data obtained were analyzed statistically using analysis of variance and continued with DNMRT at the 5% level. The analysis of variance showed that the HPMC concentration significantly affected emulsion stability, viscosity, degree of acidity, and sensory test of thickness but had no significant effect on the aroma, color, and taste of the mayonnaise. The best treatment was MV5 (5% HPMC), which had 100% emulsion stability, 70119.33 cP viscosity, 5.07 pH on day one, and 99.37% emulsion stability, 69047.33 cP viscosity, and 4.87 pH on day 15. The MV5 mayonnaise was yellowish, had a coconut taste, was slightly rancid, and was thick. The MV5 mayonnaise was more favorable than other treatments regarding the aroma, color, and taste of the mayonnaise.

Effect of Hydroxypropyl methyl cellulose (HPMC) on rheology and printability of the first printed layer of cement activated slag-based 3D printing concrete

Nowadays, Ground Granulated Blast Furnace Slag (GGBFS) is generally used to replace cement for reducing carbon emissions, but due to its low hydration activity and unstable working performance in the early stage, it is difficult to apply in 3D printed concrete (3DPC) as the main binder. In this study, a combination of ordinary Portland cement and calcium sulfoaluminate cement was used to activate GGBFS. In the presence of 0.2 wt% polycarboxylate superplasticizer (PCE), in order to achieve high-precision printing, hydroxypropyl methyl cellulose (HPMC) was used. The rheological properties of mortar were evaluated by the slugs-test and a rotational rheometer. The results show that the yield stress and thixotropy of slag cement-based 3D printing concrete are significantly increased, with addition of HPMC. The slugs-test shows its advantages in measuring rheological properties, such as superior repeatability of rheological data and a better association with 3D printing performance. Pumpability, extrudability, and buildability of the first printed layer of slag cement-based 3DPC were evaluated using pumping pressure, horizontal printing, and vertical printing. The results show that, with a 0.15 wt% HPMC, the 3D printing properties of the first layer are greatly improved, a stable and high-precision slag cement-based 3DPC can be developed, and the relationship between rheological properties and 3D printing performance can be established.

Fabrication and Optimization of Directly Compressible Self-Emulsifying Tablets Containing Cannabis Extract Obtained from Supercritical Carbon Dioxide Extraction

Δ9-Tetrahydrocannabinol and cannabidiol, which are present in cannabis extract, exhibit low bioavailability when administered orally due to significant first-pass metabolism. The use of a self-emulsifying drug delivery system (SEDDS) can enhance their dissolution and bioavailability. However, liquid SEDDS formulations are prone to inadequate stability. To address this issue, the development of a solid SEDDS formulation was explored. This study aimed to optimize directly compressible self-emulsifying tablets containing cannabis extract obtained from supercritical carbon dioxide extraction. Initially, a liquid SEDDS of cannabis extract was solidified by adsorption onto solid carriers (colloidal silicon dioxide and microcrystalline cellulose). The resulting solid mixture was then combined with other pharmaceutical excipients and compressed into tablets. Three factors were optimized using the Box-Behnken design: compressional force (1,000–2,000 psi), quantity of hydroxypropyl methylcellulose (0–6%), and quantity of croscarmellose sodium (0–6%). The results revealed that a mass ratio of colloidal silicon dioxide, microcrystalline cellulose, and liquid SEDDS of cannabis extract at 0.65:2:1 successfully solidified the mixture. The optimal tablet formulation was achieved with a compressional force of 2,000 psi, without the addition of hydroxypropyl methylcellulose or croscarmellose sodium. Verification data indicated that the predictions made by the computer software were accurate and reliable. The developed tablets exhibited improved dissolution of the cannabis extract, with Δ9-tetrahydrocannabinol demonstrating higher dissolution compared to cannabidiol. Additionally, the compressed tablets were capable of emulsifying small nano-sized droplets (approximately 200 nm). However, the droplets exhibited a larger size and broader polydispersity index compared to the liquid SEDDS. In conclusion, the study successfully developed directly compressible self-emulsifying tablets that enhanced the dissolution of cannabis extract.

Enhancing zein-starch dough and bread properties by addition of hydrocolloids

Similar to gluten, zein can form a viscoelastic network upon hydration and shear. This makes zein a promising protein to develop gluten-free bakery products. In this study, the effect of addition of different hydrocolloids (hydroxypropyl methylcellulose (HPMC), guar and xanthan gum), and the inclusion of pregelatinized starch (PG starch) and lactic acid (LA) on zein-corn starch dough and bread properties was examined. The addition of HPMC, and to a lesser extent guar gum, significantly changed the viscoelastic zein dough properties and resulted in bread samples with improved loaf volume and sensory properties. Scanning electron microscopy revealed the formation of a continuous fine foam-like structure in the zein-starch dough when HPMC and guar gum were added. This finer structure translated in a lower dough stiffness and resistance to deformation, and a higher degree of deformation characterized by lower complex moduli and increased creep compliance values. Xanthan gum addition, conversely, had an adverse effect on zein bread loaf volume which was attributed to potential weak repulsion between xanthan and zein molecules. In addition, the amount of α-helix and β-sheet secondary structures in bread samples was altered upon hydrocolloid and PG starch addition and played a role in bread crumb hardness. Overall, the zein bread with HPMC showed textural properties most similar to gluten bread. This research sheds light on different structure levels of zein-based gluten-free recipes as affected by inclusion of hydrocolloids, PG starch and LA, and provides a sound basis for the rational development of zein-based gluten-free breads.

Encapsulation of Rosemary Extracts using High Voltage Electrical Discharge in Calcium Alginate/Zein/Hydroxypropyl Methylcellulose Microparticles.

The increased demand for functional food with added health benefits is directing industrial procedures toward more sustainable production of naturally added bioactive compounds. The objective of this research was to investigate the potential of bioactive compounds from rosemary extract obtained using high-voltage electrical discharge as a green extraction method, for microencapsulation as a protective method for future application in functional food. Four types of microparticles were made via the ionic gelation method using alginate (Alg), zein (Z), and hydroxypropyl methylcellulose (HPMC) biopolymers and were analyzed considering the physicochemical properties. The diameter of dry microparticles ranged from 651.29 to 1087.37 μm. The shape and morphology analysis of microparticles showed that the obtained microparticles were quite spherical with a granular surface. The high encapsulation efficiency was obtained with a loading capacity of polyphenols up to 11.31 ± 1.47 mg GAE/g (Alg/Z microparticles). The microencapsulation method showed protective effects for rosemary polyphenols against pH changes during digestion. Specifically, the addition of both zein and HPMC to calcium-alginate resulted in microparticles with a prolonged release for better availability of polyphenols in the intestine. This research background indicates that the release of rosemary extract is highly dependent on the initial biopolymer composition with high potential for further functional food applications.

Considerations on the Kinetic Processes in the Preparation of Ternary Co-Amorphous Systems by Milling

In non-strongly interacting co-amorphous systems, addition of a polymer, to further stabilize the co-amorphous systems, may influence the phase behavior between the components. In this study, the evolution of the composition of the amorphous phase in the ternary system carvedilol (CAR)-tryptophan (TRP)-hydroxypropylmethyl cellulose (HPMC) was investigated, based upon previously formed and characterized binary systems to which the third component was added (CAR - TRP + HPMC, CAR - HPMC + TRP and TRP - HPMC + CAR). Ball milling was used as the preparation method for all binary and ternary systems. The influence of the milling time on the co-amorphous systems was monitored by DSC and XRPD. Addition of HPMC reduced the miscibility of CAR with TRP due to hydrogen bond formation between CAR and polymer. These bonds became dominant for the interaction pattern. In addition, when CAR or TRP exceeded the miscibility limit in HPMC, phase separation and eventually crystallization of CAR and TRP was observed. All ternary co-amorphous systems eventually reached the same composition, albeit following different paths depending on the initially used binary system.

Electrical and mechanical properties of self-supported hydroxypropyl methylcellulose-polyaniline conducting films.

The purpose of this work was to develop a simple method to produce self-supported films composed of hydroxypropyl methylcellulose (HPMC) and polyaniline (PANI) by the direct mixture of aqueous dispersions of both polymers with subsequent drying. The addition of HPMC, a cellulose derivative with an excellent film-forming capacity, was fundamental to overcoming the poor processability of PANI, which impairs its use in many technological applications. All films showed conductivity in the order of 10-2 to 10-3 S cm-1, which is in the range for metals or semiconductors. The typical electroactivity of PANI was also maintained in the hybrid films. The thermal stability and the mechanical properties of the pristine PANI were also improved with the addition of HPMC. Cellulose-containing conducting polymers can be considered a material of the future, with possible applications in several areas, such as smart wallpapers, e-papers, and sensors.

Synergistic adsorption of surface-active components at the air-liquid interface improves foaming properties of plant-based egg analogues

Foaming is an important functionality of eggs in aerated food products. However, plant proteins, the main components of plant-based egg analogues, are generally inferior in foaming compared to egg proteins. Hence, this study aimed to elucidate the foaming mechanisms in plant-based egg analogues modified by different amounts of hydroxypropyl methylcellulose (HPMC). The molecular adsorption at the air-liquid interface (ALI) with the mass transfer coefficients (k) was determined by a two-film theory. Plant-based egg analogue with 1.5% HPMC addition matched the foaming capacity (231% vs. 227%) and foaming stability (72% vs. 73%) of liquid egg, due to the thermodynamic incompatibility between biomacromolecules in the vicinity of the ALI that accelerated the protein and lipid adsorption through depletion mechanism (23.2 and 22.7 to −67.8 μm/min for kprotein and klipid, respectively). This led to the highest volumetric synergy, consistency, and elasticity in the foams made thereof. Foams containing less HPMC did not have fast molecular adsorption, probably due to less HPMC on inducing synergistic adsorption. Foams contained more HPMC exhibited HPMC-dominated ALI, competing with protein and lipid adsorption, and reducing foaming properties. It is concluded that HPMC imparts dose-dependent effect on the molecular adsorption at the ALI, which determines the foaming properties of the plant-based egg analogues. Furthermore, this study showed that plant-based egg analogue modified with 1.5% HPMC was promising in sponge cake and omelet production. Accordingly, a series of composite eggless systems based on foaming characteristics can be developed by adjusting the additive amount of HPMC according to actual needs.

Interaction of polymers with bile salts – Impact on solubilisation and absorption of poorly water-soluble drugs

Formulating poorly soluble drugs with polymers in the form of solid dispersions has been widely used for improving drug dissolution. Endogenous surface-active species present in the gut, such as bile salts, lecithin and other phospholipids, have been shown to play a key role in facilitating lipids and poorly soluble drugs solubilisation in the gut. In this study, we examined the possible occurrence of interactions between a model bile salt, sodium taurocholate (NaTC), and model spray dried solid dispersions comprising piroxicam and Hydroxypropyl Methylcellulose (HPMC), a commonly used hydrophilic polymer for solid dispersion preparation. Solubility measurements revealed the good solubilisation effect of NaTC on the crystalline drug, which was enhanced by the addition of HPMC, and further boosted by the drug formulation into solid dispersion. The colloidal behaviour of the solid dispersions upon dissolution in biorelevant media, with and without NaTC, revealed the formation of NaTC-HPMC complexes and other mixed colloidal species. Cellular level drug absorption studies obtained using Caco-2 monolayers confirmed that the combination of drug being delivered by solid dispersion and the presence of bile salt and lecithin significantly contributed to the improved drug absorption. Together with the role of NaTC-HPMC complexes in assisting the drug solubilisation, our results also highlight the complex interplay between bile salts, excipients and drug absorption.

Effects of Hydroxypropyl Methylcellulose on Physicochemical Properties and Microstructure of κ-Carrageenan Film.

We investigated the effects of different proportions of hydroxypropyl methylcellulose (HPMC) on the properties of κ-carrageenan film. Biodegradable κ-carrageenan/HPMC films (κCHM film) were prepared by the solution casting method and their physicochemical properties were evaluated. The results show that the addition of HPMC enhanced oxygen barrier capacity, mechanical properties (tensile strength and elongation at break) and thermal stability. Notably, when the addition of HPMC increased to 6% of κ-carrageenan (w:w), the κCHM-6 film not only effectively improved water resistance, including lower water solubility, water vapor permeability and higher water contact angle, but also made the structure of the κCHM-6 film more compact. Moreover, rheological measurement and atomic force microscopy characterization showed that κ-carrageenan had suitable compatibility with HPMC. Attenuated total reflection–Fourier transform infrared spectroscopy analysis further confirmed the enhancement of hydrogen bond interactions. This finding could contribute to promoting the potential application of κCHM film in food packaging.

Role of hydrocolloids in improving the rheology, quality characteristics, and microstructure of gluten‐free proso millet bread

SummaryThe effect of xanthan gum (XG), guar gum (GG), and hydroxypropyl methylcellulose (HPMC) at different concentrations (0.5, 1.0, 1.5, 2.0 g/100 g) on the development of gluten‐free proso millet bread was studied. HPMC and GG addition showed a remarkable increase in the loss and storage modulus, indicating the viscoelastic behaviour of batter. With increasing frequency, loss tangent values decreased <1, denoting gel‐like behaviour. Shear stress increased, and apparent viscosity decreased with shear rate denoting pseudoplastic non‐Newtonian fluid behaviour. HPMC and GG added batter showed improvement in stickiness, adhesion, cohesiveness, and vice versa observed in XG. HPMC2.0 and GG2.0 showed higher loaf and specific volume (450, 446.67 cm3 and 2.88, 2.85 cm3 g−1). It signifies increased gas holding capacity, which reduces the hardness of the crumb than control. HPMC breads showed higher number of cells, uniform cell size, thin cell wall, and lower porosity with the highest overall acceptability (7.33). Microstructure exhibited continuous network formation in HPMC2.0 crumb compared to web‐like structures in XG and GG breads. Immunological validation showed that the developed bread was gluten free. The results implied that the addition of 2 g/100 g HPMC improved the overall quality of proso millet bread.

Effect of hydroxypropyl methylcellulose, protein and fat on predicted glycemic index and antioxidant property of gluten‐free bread from rice flour

Due to the lack of gluten, hydroxypropyl methylcellulose (HPMC), whey protein concentrate (WPC) and soy protein isolate (SPI) were fortified (4 g/100 g flour) into gluten-free bread made from rice flour. The heteropolymer structure of HPMC and protein covered starch granules, resulting in a decrease in predicted glycemic index (pGI) of bread from 84.08 to 67.20–71.04. Addition of butter reduced the pGI to 73.55. By changing the baking mode from hot air baking to microwave baking and microwave-hot air baking, the pGI was reduced from 73.55 to 70.51–70.81 (p ≤ 0.05). With addition of HPMC or/ and protein, the gluten-free bread exhibited stronger inhibition of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals than the wheat bread. Therefore, starch digestibility of the gluten-free bread was mainly reduced by mixture of HPMC, proteins and butter in the dough recipe. Addition of HPMC and WPC further benefited the improvement of antioxidant activity by DPPH assay. Practical applications The finding of this research was the technique to manipulate GI and antioxidant activity in the rice-flour bread by microwave assisted baking process and addition of HPMC, WPC and butter. The outcome of this research could increase health benefit of gluten-free bread from rice flour, in terms of slow starch digestion and high antioxidant activity.

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.

Effects of Hydroxypropyl Methylcellulose (HPMC) on the Reinforcement of Sand by Microbial-Induced Calcium Carbonate Precipitation (MICP)

Microbial-induced calcium carbonate precipitation (MICP) is a new technology used for reinforcing soils through microbial mineralization. However, the existing MICP treatment technology is more suiTable for deeper soils due to its high permeability. In this study, HPMC, a cohesive material combined with Sporosarcina pasteurii-induced calcium carbonate precipitation was used to improve the surface layer of the soil. It was also tested in different contents of bacterial solutions and cementation solutions and with a different number of MICP treatments, and was analyzed and discussed by measuring the surface layer strength, calcium carbonate content generated in the crust, rainfall erosion resistance, wind erosion resistance, and ammonia retention rate of the specimens. The microstructure of the samples was investigated by XRD and SEM. It was shown that the addition of HPMC and increasing the number of MICP treatments were effective in the increase in the calcium carbonate content in the surface crust, but had no effect on the total amount of induced calcium carbonate. The combination of HPMC addition and MICP technology can effectively reduce rainwater scour loss and wind erosion loss, and increase its rainfall erosion resistance and wind erosion resistance. Rainfall losses were reduced by up to 30% in specimens treated with HPMC for MICP technology. When the wind speed was 12 m/s, the maximum mass loss rate of the specimens treated with HPMC for MICP was only 0.828%. The addition of HPMC can effectively improve the ammonia absorption rate and reduce the release of ammonia in the process of MICP technology, which is of great significance for environmental protection. The microstructure showed that the addition of HPMC and the increase in the number of treatments using MICP technology can make the surface structure of the specimens more compact, and the calcium carbonate can more effectively fill the pores and cement the soil particles, while the addition of HPMC may not change the calcium carbonate crystal type.

Fabrication of hybrid povidone-iodine impregnated collagen-hydroxypropyl methylcellulose composite scaffolds for wound-healing application

Biomaterials derived from biological resources are advantageous in tissue engineering owing to their biocompatibility. This work presents the fabrication of a collagen composite scaffold in combination with hydroxypropyl methylcellulose (HPMC). Based on FTIR spectroscopic analysis, it is established that the native structure of collagen (Col) is unaltered with the addition of HPMC in making collagen-HPMC (ColH) composite scaffolds. Scanning electron microscopic (SEM) examination shows a smooth surface with interconnected pores in the prepared hybrid scaffolds. Considering the mechanical properties, collagen degradation, and biocompatibility, the ColH scaffold comprising 1:1.5 (w/w) of Col: HPMC was found to be optimum for applications such as wound healing and other soft tissue engineering applications. In order to determine drug loading ability of the ColH scaffold, Povidone-iodide (PI) was used as a model drug. PI loaded ColH exhibited controlled release of the drug. Further, the in vitro studies of the synthesized drug-loaded ColH scaffold showed that they effectively facilitated the proliferation of NIH3T3 fibroblasts cells without exhibiting toxicity. This study establishes the possibility of using ColH as an effective and advanced option for regenerative tissue engineering applications.

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.

Improvement on compactibility of the alcoholic extract of Zingiberis Rhizoma by co-spray drying with HPMC

Aiming to solve the poor compactibility of the alcoholic extract of Zingiberis Rhizoma(ZR), this study explored the feasibility of its physical modification using co-spray drying with a small amount of hydroxypropyl methyl cellulose(HPMC). Based on the univariate analysis, the influence of two independent variables(the HPMC content in the product and the solid content of spray material) on the powder properties and tablet properties of the dried product was investigated by the central composite design. With the tensile strength and disintegration time of the tablets as the evaluation indexes, the optimal prescription was determined as follows: the HPMC content was 15% and the solid content of spray material was 25.6%. The accuracy of the regression model established for predicting tensile strength and disintegration time of tablets was verified, and the results revealed that the measured values were close to the predicted ones with deviations of 0.47% and-8.2%, indicating good prediction and reproducibility of the model. The tensile strength(4.24 MPa) of tablets prepared with the optimal prescription was 3.59 times that(1.18 MPa, far lower than the baseline of 2 MPa for qualified tablets) with the spray-dried powder of the ZR. On the other hand, due to the addition of HPMC, the disintegration time of tablets increased from 7.3 min to 24.6 min. On the whole, this study provided a new strategy to solve the common problem of poor compactibility of raw Chinese medicinal materials, which facilitated the successful preparation of Chinese medicinal tablets with high drug loads.

Determination of the pH- and thermal stability mechanism of lipophilic protein–hydroxypropyl methylcellulose oil-in-water emulsion

The aim of this study is to investigate the mechanism through which hydroxypropyl methylcellulose (HPMC) addition improves the stability of soybean lipoprotein (LP) under acidic conditions and the thermal stability of LP-HPMC emulsions. Results of SDS-PAGE, Raman spectroscopy, and X-ray diffraction studies reveal that the active sites of the LP-HPMC complexes varied with a change in pH and the amide III bands and the polarity of the microenvironment decrease with increasing HPMC content. The LP-HPMC complex does not form new subunits or crystals, but forms non-covalent bonds exploiting electrostatic and hydrophobic interactions. The addition of HPMC results in a change in the microstructure and droplet size distribution of LP-HPMC emulsions and an increase in the LP denaturation temperature; thus, the thermal stability of the emulsion decreases. This study can help develop non-heated emulsion delivery systems that remain stable in the gastric environment and promote the targeted release in the intestines.

Clinical Demonstrations of Controlled-Release Tablets Constructed by the Combined Usage of Shellac and Hydroxypropyl Methylcellulose

A new tablet system was examined for an intestinal delivery system using hydroxypropyl methylcellulose (HPMC) and shellac. HPMC was incorporated into the inside of the tablet, and shellac was coated on the surface, which was evaluated for its controlled-release property through several dissolution tests, firstly in vitro and then via two kinds of clinical studies with healthy volunteers. The clinical studies were originally designed by employing X-ray photography for the movements of the tablets in the gastrointestinal tract and an electronical device to easily analyze the absorption profile of glucose, a model compound. It was found that the dissolution of the tablet was strongly suppressed in a simulated gastric fluid (pH 1.2) and subsequently started to disintegrate in a simulated intestinal fluid (pH 6.8). The first human study with X-ray photography revealed that the model tablets could pass through the stomach without disintegrating. The controlled release of the tablets was further confirmed via analyses of the AUC, Cmax, and Tmax for the blood glucose concentration with other volunteers. The AUC and Cmax were significantly reduced by using our system, thus concluding that the delivery system combined with the addition of HPMC and a shellac coating unequivocally leads to controlled release in the human gastrointestinal tract.

HPMC improves protective effects of naringenin and isonicotinamide co-crystals against abdominal aortic aneurysm.

Abdominal aortic aneurysm (AAA) rupture is one of the most common causes of mortality in cardiovascular diseases, but currently there is no approved drug for AAA treatment or prevention in the clinic. Naringenin (NGN) has been reported to have anti-AAA effects. However, water solubility and in vivo absorption of NGN are not satisfactory, which leads to its low bioavailability, thus affecting its pharmacological effects. In this project, the improving effects of isonicotinamide (INT) co-crystal and hydroxy propyl methyl cellulose (HPMC) or polyvinyl pyrrolidone (PVP) on the solubility, in vivo absorption, and anti-AAA effects of NGN were evaluated. In the current study, co-crystals of naringenin-isonicotinamide (NGN-INT) were prepared, and effects of PVP or HPMC on precipitation rate, supersaturation, and bioavailability of NGN were explored. In addition, with or without HPMC supply, the effects of NGN-INT co-crystal on anti-AAA efficacy of NGN were investigated on an elastase-induced AAA mouse model, and the results were compared with the efficacy of the NGN crude drug. Our results demonstrate that NGN-INT formulation, compared to the NGN crude drug, enhanced the dissolution rate of NGN and significantly increased Cmax and AUC(0-∞) of NGN by 18 times and 1.97 times, respectively. Addition of PVP or HPMC in NGN-INT co-crystal further increased bioavailability of NGN in NGN-INT. The in vivo pharmacodynamic study showed that NGN-INT with HPMC significantly improved the inhibitory effects of NGN against AAA. NGN-INT significantly improved the absorption and aortic protective effects of NGN. The supersaturation-prolonging effect of HPMC further enhanced bioavailability and anti-AAA effects of NGN-INT.