Improved Storage Stability Research Articles

APA-style human milk fat analogue from silkworm pupae oil: Enzymatic production and improving storage stability using alkyl caffeates.

Silkworm pupae oil derived from reeling waste is a rich source of α-linolenic acid (ALA), which has multipal applications. ALAs were added in sn-1, 3 positions in a triacylglycerol (TAG) to produce an APA-human milk fat analogues (APA-HMFAs, A: α-linolenic acid, P: palmitic acid). The optimum condition is that tripalmitin to free fatty acids of 1:12 (mole ratio) at 65 °C for 48 h using lipase Lipozyme RM IM. Results show that, the major TAG species that comprised APA-HMFAs were rich in ALA and palmitic acid, which contained 64.52% total unsaturated fatty acids (UFAs) and 97.05% PA at the sn-2 position. The melting point of APA was −27.5 °C which is much lower than tripalmitin (40.5 °C) indicating more plastic character. In addition, the practical application of alkyl caffeates as liposoluble antioxidants in APA was developed. Alkyl caffeate showed a superior IC50 (1.25–1.66 μg/mL) compared to butyl hydroxy anisd (1.67 μg/mL) and L-ascorbic acid-6-palmitate (L-AP) (1.87 μg/mL) in DPPH analysis. The addition of ethyl caffeate to oil achieved a higher UFAs content (73.58%) at high temperatures. Overall, APA was obtained from silkworm pupae oil successfully, and the addition of caffeates extended storage ranges for APA-HMFAs.

Microencapsulation and Storage Stability of Lycopene Extracted from Tomato Processing Waste

The aim of this study was to optimize the encapsulation of lycopene using response surface methodology and to determine its stability. The lycopene was extracted from tomato processing industry waste. The extracted pigment was purified by crystallization method. The effect of different process parameters, viz, core to wall ratio, sucrose to gelatin and inlet temperature on encapsulation efficiency (EE) and encapsulation yield (EY) were studied. Structural study of encapsulated material was carried by using scanning electron microscope (SEM). The samples with and without encapsulation were stored under different conditions such as the presence and absence of air, sunlight, at room temperature and under refrigeration. Highest EE (92.6 ± 0.86) and EY (82.2 ± 0.95) were observed when the core to wall ratio was 1:4, sucrose to gelatin ratio was 7:3 and inlet temperature was 1800C. The SEM analysis showed the encapsulated lycopene was of "bee-net" shaped, whereas lycopene without encapsulation was like "saw dust". More than 90% retention was recorded in microencapsulated sample stored in all storage conditions, whereas sample without encapsulation showed less than 5% retention with sample storage conditions after 42 days of storage. The optimization and storage study would be helpful to the lycopene producer to improve storage stability.

Effective lipophilic antioxidant enzymatically derived from Canadian crabapple

Phloridzyl octadecanoate was prepared by enzymatic reaction between the native phloridzin in Canadian crabapple (Malus baccata) extract and octadecanoic acid in the presence of Candida antarctica lipase. The antioxidant activity of the modified extract was assessed in rapeseed oil during accelerated storage at 65°C and frying at 180°C. Addition of 0.1% modified extract to refined, bleached, and deodorized rapeseed oil significantly improved storage stability with 40.7% decrease in the formation of lipid hydroperoxides at the end of the 7‐day storage compared to rapeseed control sample without extract; however, no significant difference was observed in the potency of the modified extract and that of the native extract. On the contrary, the modified extract offered markedly better protection to the rapeseed substrate during frying, inhibiting polar component formation, and polymerization of triacylglycerol by up to 44%, compared to 26% by the native extract. At the end of the frying, French fries prepared in the presence of modified extract retained significantly more tocopherols than those prepared with the native extract indicating better protection of the oil's endogenous antioxidants by the modified phenolic extract.Practical applications: Poor lipophilicity is a major challenge to the application of natural polyphenolic compounds in edible oils. Equally challenging is the development of natural antioxidants that can maintain effectiveness under the stringent dynamic conditions of frying. Results from the current study demonstrated the possibility of overcoming these challenges, providing food processors with lipophilic natural antioxidants of practical importance in the frying process.Improving the lipophilicity of the polyphenolic components of Canadian crabapple's extract resulted in enhanced antioxidant and antipolymerization activities during frying, with consequent decreased in: Total polar materials (TPM); di‐ and polymerized triacylglycerols (DPTG); formation of non‐volatile carbonyl compounds assessed by the anisidine value (AnV); and rate of endogenous tocopherol degradation. However, no change in activity was observed under storage conditions.

Covalently Immobilized Laccase for Decolourization of Glucose-Glycine Maillard Products as Colourant of Distillery Wastewater.

Maillard reaction products like melanoidins are recalcitrant, high-molecular-weight compounds responsible for colour in sugarcane molasses distillery wastewater. Conventional biological treatment is unable to break down melanoidins, but extracellular laccase and manganese peroxidase of microbial origin can degrade these complex molecules. In this work, laccase was covalently immobilized on alumina pellets activated with aminopropyltriethoxysilane (APTES). The immobilization yield was 50-60 %, and the enzyme activity (886 U/L) was 5-fold higher compared to the soluble enzyme (176 U/L). The immobilized enzyme also showed higher tolerance to pH (4-6) and temperature (35-60 °C), as well as improved storage stability (49 days) and operational stability (10 cycles). Degradation of glucose-glycine Maillard products using immobilized laccase led to 47 % decolourization in 6 h at pH 4.5 and 28 °C. A comprehensive treatment scheme integrating enzymatic, microbial and membrane filtration steps resulted in 90 % decolourization.

일본, 말레이시아, 오만의 기록물에서 분리한 유해미생물에 대한 친환경 기록물 소독장비 효과검증

Archives have historical and academic values. That is why the study of preservation conditions and the environment for the effective management of various records progress. However, materials such as paper and adhesives will inevitably cause biological damages. These damages spread into the inner side of archives, which would make it impossible to recover. For example, archival records from Malaysia and Oman are easily exposed to biological damage because of these countries` hot and humid climate. As such, once records are damaged, disinfection operations are customary in these areas. Methyl bromide (MeBr) and ethylene oxide (EtO) were used in the disinfection process as they showed good insecticidal effect. However their antibacterial effect are negligible. As such, the need for an environmental-friendly fumigator was evident. An environmental-friendly fumigator is designed to improve storage stability. Such equipment is expected to contribute to prevention of damages to cultural heritages through its use of vaporization technology, maintenance of a disinfection space (chamber), and self-generation of nitrogen.

Extreme Long Life Battery Via Atomic Layer Deposition of Solid Electrolyte on CFx Electrodes

Modern defense and commercial applications, such as environmental sensors or implantable medical devices, require battery power sources with a wide operating temperature range, excellent reliability, an ability to resist abuse including mechanical vibrations and shock, high energy density and extreme long battery life (20 years). Unfortunately, state-of-the-art (SOA) battery power sources cannot adequately meet the combined energy density and long life requirements. Here we present a promising method to prepare extreme long life batteries via atomic layer deposition (ALD) of solid electrolyte onto inherently high energy density and stable CFxelectrodes. Figure 1 shows discharge voltage profiles of cells containing ALD solid electrolyte coated electrodes, overlaid with a control cell without oxide coating. The anode was metallic lithium and a conventional Li-ion electrolyte was used. The cells were discharged with a constant, one-year current rate, a relatively fast rate for 20 year service life. The ALD solid electrolyte coated cell showed no voltage delay at the initial discharge which is shown in the control cell, a phenomenon characteristic of CFx chemistry which is believed to result from the low conductivity of fresh CFx materials [1]. The elimination of the voltage delay presents significant performance advantages at start-ups. The ALD solid electrolyte coated CFxcells demonstrated more than 60mV higher discharge running voltage than that of the control cell, resulting in higher energy density and, potentially, longer battery service life. Figure 2 shows Nyquist plots of electrochemical impedance spectroscopy (EIS) carried out for ALD solid electrolyte coated and the control cells. The ALD solid electrolyte coated cell showed a much smaller semi-circle representing a 66% smaller charge transfer resistance (leading to faster charge transfer kinetics) than the control cell. The EIS data strongly support the improved discharge performance presented above. We will show that ALD enabled solid electrolyte coatings on CFx lead to significantly improved storage stability at extreme temperatures (e.g. 85°C) and superior after-storage discharge performance, compared with CFxwithout coating. Our results in this study suggest solid electrolyte coating via ALD on CFx is a promising material processing methodology for extreme long life battery power sources with a complete elimination of CFx voltage delay and significantly enhanced charge transfer kinetics, energy density and electrochemical stability at extreme temperatures. Such methodology is potentially scalable economically when high throughput and high volume ALD processes are implemented. Reference Sheng S. Zhang, Donald Foster, Jeff Wolfenstine, Jeffrey Read, Journal of Power Sources 187, 233 (2009). Figure 1

An investigation on using pre-treated tyre rubber as a replacement of synthetic polymers for bitumen modification

Rubberised bitumen obtained through a swelling process, has widely proved to be a successful technology for asphalt pavement applications and a solution to reduce the dismantling of tyre rubber on landfills. However, this technology presents two main operative issues which need the adoption of costly special equipment. First, significant high value of high-temperature viscosity (HTV), which imposes mixing and compaction difficulties, leads to increased energy consumption and emissions. Furthermore, during the hot storage period, phase separation between rubber particles and the base bitumen could occur. Developing recycled tyre rubber-modified bitumen (RTR-MB) with improved storage stability and reduced values of HTV could allow using this technology in standard asphalt plants, resulting in an environmental-friendly and cost-effective option of standard polymer-modified bitumen. In this study, two different pre-treated and one straight ambient recycled rubbers were used to produce RTR-MB. The first RTR was pre-treated by special oil and warm-mix additives and the second was partly de-vulcanised. Also, two base binders were selected with large differences in mechanical properties in order to identify the effect of base binder. The HTV was successfully reduced by using pre-treated RTR. The use of RTR together with Fischer–Tropsch wax (Sasobit®) in bitumen technology offered superior high in-service temperature properties and reduced value of HTV, and thus can be the preferred option over styrene–butadiene–styrene modification.

Biomimetic PVPA in vitro model for estimation of the intestinal drug permeability using fasted and fed state simulated intestinal fluids

A prerequisite for successful oral drug therapy is the drug’s ability to cross the gastrointestinal barrier. Considering the increasing number of new chemical entities in modern drug discovery, reliable and fast in vitro models are required for early and efficient prediction of intestinal permeability. To mimic the intestinal environment, use of biorelevant media may provide valuable information on in vivo drug permeation. The present study aims at improving the novel biomimetic phospholipid vesicle-based permeation assay’s (PVPAbiomimetic) biorelevance by investigating the applicability of the biorelevant media; fasted state simulated intestinal fluid (FaSSIF) and fed state simulated intestinal fluid (FeSSIF). The FaSSIF and FeSSIF’s influence on the permeability of the model drugs acyclovir, indomethacin, griseofulvin and nadolol was then assessed. The barriers’ robustness in terms of storage stability was also evaluated. The barriers were found to maintain their integrity in presence of FaSSIF and FeSSIF. The model drugs showed changes in permeability in presence of the different simulated intestinal fluids that were in agreement with previous reports. Moreover, the barrier showed improved storage stability by maintaining its integrity for 6months. Altogether, this study moves the PVPAbiomimetic an important step towards a better in vitro permeability model for use in drug development.

Esterification of sugar beet pectin using octenyl succinic anhydride and its effect as an emulsion stabilizer

Sugar beet pectin (SBP) was esterified using octenyl succinic anhydride (OSA) and potassium carbonate, as a catalyst, at 160 °C. The structure of the product, octenyl succinate sugar beet pectin (OS-SBP), was characterized by Fourier transform infrared (FT-IR), Raman and 1H NMR spectroscopy, which demonstrated that OSA groups had been introduced into the SBP molecules and most OS substitution occurred at the C-3 position. SBP- and OS-SBP-stabilized oil-in-water emulsions prepared at a concentration of 1.0% (w/w) were compared using 20% middle-chain triglyceride (MCT) as the oil phase. The properties of emulsions stabilized by SBP and OS-SBP were evaluated via surface tensiometry, microscopy, determination of the creaming index (CI) and droplet size distribution. The results showed that emulsions stabilized by OS-SBP with a low degree of substitution (DS) possessed a smaller oil droplet size and improved storage stability compared with those of the emulsion generated using SBP. The decalcification could improve the emulsifying properties of OS-SBP. The results suggested that OS-SBP with a DS of 1.8 would be a strong emulsifying agent in acidic environments.

Improving storage stability of recombinant organophosphorus hydrolase

Organophosphorus hydrolase (OPH) is a ∼38kDa enzyme encoded by opd gene of Flavobacterium sp. The enzyme can hydrolyze and inactivate variety of organophosphate (OP)-compounds, including chemical warfare nerve agents. Thus, OPH is a strong candidate for the development of therapeutic intervention against OP-poisoning in humans and other animals. It is also a promising bio-decontaminating agent for clean-up of OP-contaminated objects and areas. For successful commercial application, long-term storage stability of purified OPH enzyme is important. In this study we have cloned and expressed recombinant OPH (r-OPH) in Escherichia coli and the effect of different excipients on the long-term storage stability of purified enzyme was analyzed. The enzyme was stored in either aqueous solution or in lyophilized form at 25°C for 60days in the presence or absence of different excipients and the stability of the enzyme was determined by monitoring the paraoxon-hydrolyzing activity. Our results suggest that, (a) maltose, trehalose, arginine and proline were most effective in stabilizing the enzyme when stored in aqueous buffer at 25°C, and (b) maltose, trehalose, and mannose exerted maximum stabilization effect when the enzyme was stored in lyophilized form at 25°C for 60days. The study shows that common excipients can be used to stabilize purified OPH enzyme in order to store it for long period of time under different storage conditions. The results of this study can be used to develop formulation(s) of OPH enzyme for commercial use.

Improvement of oxidative stability of menhaden fish oil by microencapsulation within biocapsules formed of yeast cells

Fish oil, rich in polyunsaturated fatty acids, is a valuable addition to human diet. Its composition makes it difficult to handle as it is prone to oxidation and its strong smell is repelling to many. Encapsulation in yeast cells is a possible solution to these issues. The aim of this study was to determine the best pretreatment approach, optimize the process of microencapsulation and verify the stability of the oil encapsulated in Saccharomyces cerevisiae. Pretreatment by autolysis, chemically facilitated autolysis and enzymatic cell wall digestion was tested. Autolysis at 55°C supported by addition of 1.5% ethyl acetate was an effective pretreatment method. Process parameter values (temperature, stirring rate and emulsifier addition) were optimized, improving efficiency to ca. 90%. The encapsulated oil was shown to be stable when stored for 30days at relative humidity below 70%. Additional coating with hydroxypropyl methyl cellulose allowed to improve storage stability.

Urease-carrying electrospun polyacrylonitrile mat for urea hydrolysis

Electrospinning was used to fabricate beadless microfibrous polyacrylonitrile (ePAN) mats with an average fiber diameter of 1448±380nm from a 10wt.% PAN in dimethylformamide (DMF) dope solution at applied voltage of 18kV and 20cm fiber collection distance. Urease (EC 3.5.1.5) was then covalently immobilized on dispersed microfibrous ePAN mats following the chemical treatment of fibers with ethylenediamine (EDA) and glutaraldehyde (GA). The optimal concentration of GA for immobilization was 5%. The amount of loaded urease reached 157μg/mg mat, exhibiting 54% of the free urease activity. The surface chemistry of as-spun and chemically treated fibers was examined with Fourier transform infrared (FTIR) spectroscopy. Field emission scanning electron microscopy (FESEM) was used to study the morphology and diameter of the pristine, chemically treated, and urease-immobilized microfibrous mats. Immobilized urease showed increased temperature for maximum activity (from 37 to 50°C for free and immobilized urease, respectively) and improved storage stability (20days). The immobilized urease was also less sensitive to the changes in pH, especially in acid conditions. In addition, nearly 70% of initial activity of the immobilized urease was retained after 15 cycles of reuse, which proved the applicability of the electrospun fibers as successful enzyme carriers.

Preparation of betulinic acid nanoemulsions stabilized by ω-3 enriched phosphatidylcholine

Bioactive compounds such as ω-3 fatty acids and terpenes, have been associated with beneficial health effects; however, their solubility in the gastrointestinal tract and its bioavailability in the body are low. Nanoemulsions offer a viable alternative to disperse lipophilic compounds and improve their dissolution, permeation, absorption and bioavailability. Enzyme modified phosphatidylcholine (PC) with ω-3 fatty acids was used as emulsifier to stabilize oil-in-water nanoemulsions generated using ultrasound device. These systems were used as carriers of betulinic acid, which has reported anti-carcinogenic activity. Phospholipase-catalyzed modification of PC allowed the incorporation of 50mol% of ω-3 fatty acids. Formation variables such as oil type and ultrasound amplitude had effects on nanoemulsion characteristics. Incorporation of betulinic acid affected globule size; however, betulinic acid nanoemulsions below 200nm could be prepared. The conditions under which betulinic acid nanoemulsions were obtained using the modified phosphatidylcholine with the smaller globule size (91nm) were 10% PC, 25% glycerol, medium chain oil and 30% amplitude for 12min in the sonicator. Storage temperature had an effect on the stability of the nanoemulsions, at 5°C we observed the smallest growth in globule size. The use of olive oil decreased the globule size growth during storage of the nanoemulsion stabilized with modified phosphatidylcholine, although globule size obtained was greater than 200nm. Medium pH had a significant effect on the nanoemulsions; alkaline pH values improved storage stability. These results provide useful information for using this type of carrier system on the formulation of products in the pharmaceutical or food industry.

Nutraceutical enriched Indian traditional chikki.

Chikki or peanut brittle, a traditional sweet snack was chosen as vehicle for enrichment with added natural nutraceuticals through herbs. The formulation and process for preparation of chikki with added herbs like ashwagandha (Withania somenifera), tulasi (Ocimumsanctum L.) and ajwain (Trachyspermum ammi S.) were standardized. The polyphenol content of chikki with added herbs ranged 0.29-0.46g/100g. Among the herbs, ajwain showed more potent antioxidant activity followed by tulasi, whereas ashwagandha and product prepared with it showed the least activity. Total carotenoid contents of chikki with added herbs ranged between 1.5 and 4.3mg/100g. Storage studies showed that chikki prepared with tulasi and ajwain were sensorily acceptable up to 90days, while rancid notes were observed in control and chikki with added ashwagandha at the end of 30days. Thus chikki with added herbs in addition to containing natural nutraceuticals like polyphenols and carotenoids had improved storage stability compared to control.

Biocatalytic polymer nanofibers for stabilization and delivery of enzymes

Electrospun water-soluble nanofibers as enzyme supports have potential to overcome limitations of traditional immobilization by increasing the surface area-to-volume ratio, reducing diffusional limitations, and improving storage stability. In this study, β-galactosidase (lactase, Aspergillus oryzae) was electrospun into polyethylene oxide (PEO) nanofibers with Pluronic F-127 (F127) (polyethylene oxide/polypropylene oxide block copolymer) to enable dry storage stability and subsequent rapid dissolution upon use in applications such as sensing, bioactive packaging, and bioprocessing. Nanofibers were cylindrical (average diameter ∼300nm) and exhibited no beading after spinning or storage. After electrospinning, enzymes retained up to 92% of their native activity. After 4 weeks storage, the immobilized enzyme fiber retained up to 44% of the activity of the original fiber. These results suggest that co-spinning enzymes in a polymer nanofiber matrix can improve activity retention and dry storage stability compared to traditional immobilization methods and enables rapid dissolution for ease of use.

Laccase Immobilization by Chelated Metal Ion Coordination Chemistry

In this work, amidoxime polyacrylonitrile (AOPAN) nanofibrous membrane was prepared by a reaction between PAN nanofibers and hydroxylamine hydrochloride. The AOPAN nanofibrous membranes were used for four metal ions (Fe3+, Cu2+, Ni2+, Cd2+) chelation under different conditions. Further, the competition of different metal ions coordinating with AOPAN nanofibrous membrane was also studied. The AOPAN chelated with individual metal ion (Fe3+, Cu2+, Ni2+, Cd2+) and also the four mixed metal ions were further used for laccase (Lac) immobilization. Compared with free laccase, the immobilized laccase showed better resistance to pH and temperature changes as well as improved storage stability. Among the four individual metal ion chelated membranes, the stability of the immobilized enzymes generally followed the order as Fe–AOPAN–Lac > Cu–AOPAN–Lac > Ni–AOPAN–Lac > Cd–AOPAN–Lac. In addition, the immobilized enzyme on the carrier of AOPAN chelated with four mixed metal ions showed the best properties.

Surface-Initiated Ring-Opening Polymerization of Poly(2-methyl-2-oxazoline) from Poly(bromoethyl methacrylate/methyl methacrylate) Microspheres and Modification into PEI: Immobilization of α-Amylase by Adsorption and Cross-Linking

Bromide-functionalized microspheres were prepared by the suspension polymerization of bromoethyl methacrylate (BEMA), methyl methacrylate (MMA), and ethylene glycol dimethacrylate (EGDMA). The microspheres were employed as a solid macroinitiator for the ring-opening polymerization of 2-methyl 2-oxazoline. The surface brushes were then converted into poly(ethylenimine) (PEI) by simple hydrolysis with HCl and then NaOH as inferred from chemical analyses and FTIR spectra. The microspheres were used for the immobilization of α-amylase through adsorption and covalent cross-linking. The optimum pH for free enzyme was 6.0 and shifted by about 1.0 unit to the acidic pH range upon immobilization. Compared to free α-amylase, the immobilized enzyme preparations were found to exhibit better tolerance to variations in pH and temperature, as well as improved storage stabilities. The activity retentions of the adsorbed and cross-linked enzyme preparations were found to be 69% and 53%, respectively. Furthermore, the cros...

Freeze-drying of HI-6-loaded recombinant human serum albumin nanoparticles for improved storage stability

Severe intoxications with organophosphates require the immediate administration of atropine in combination with acetyl cholinesterase (AChE) reactivators such as HI-6. Although this therapy regimen enables the treatment of peripheral symptoms, the blood–brain barrier (BBB) restricts the access of the hydrophilic antidotes to the central nervous system which could lead to a fatal respiratory arrest. Therefore, HI-6-loaded albumin nanoparticles were previously developed to enhance the transport across this barrier and were able to reactivate organophosphate-(OP)-inhibited AChE in an in vitro BBB model. Since HI-6 is known to be moisture-sensitive, the feasibility of freeze-drying of the HI-6-loaded nanoparticles was investigated in the present study using different cryo- and lyoprotectants at different concentrations. Trehalose and sucrose (3%, w/v)-containing formulations were superior to mannitol concerning the physicochemical parameters of the nanoparticles whereas trehalose-containing samples were subject of a prolonged storage stability study at temperatures between −20°C and +40°C for predetermined time intervals. Shelf-life computations of the freeze-dried HI-6 nanoparticle formulations revealed a shelf-life time of 18months when stored at −20°C. The formulations’ efficacy was proven in vitro by reactivation of OP-inhibited AChE after transport over a porcine brain capillary endothelial cell layer model.

Effect of enzyme-assisted extraction on the chilled storage stability of bilberry (Vaccinium myrtillus L.) anthocyanins in skin extracts and freshly pressed juices

Three different commercial enzyme preparations were evaluated with respect to the extractability and chilled storage (10°C, 9days) stability of bilberry skin anthocyanins in model systems. Using ultra high-performance liquid chromatography–diode array detection, 15 individual anthocyanins were characterized, with delphinidin and cyanidin glycosides being the predominant compounds. Except for the galactosides of cyanidin and peonidin, 1.2–4.7 times higher concentrations of individual anthocyanins were observed for the extracts from enzymatically treated bilberry skin suspensions. Anthocyanin degradation followed well (R2=0.89–0.98) a first-order reaction kinetics and the half-life values increased (12–64%) due to enzyme-assisted extraction. The results obtained demonstrate an improved storage stability of anthocyanins, enzymatically released from the bilberry skin matrix. On the basis of the enzyme screening assay, a novel process, composed of partial dejuicing (pressing, ~40% juice yield) of the bilberry mash followed by enzymatic maceration (EMPD), was developed. Interestingly, enzymatic treatment resulted in a decrease among counts of mesophilic and psychrotrophic microorganisms and moulds and yeasts in the bilberry juice upon chilled storage (10°C, 9days), implying an inhibition of the microbial growth. Therefore, applying the EMPD process, this two-step juice extraction technology may be very helpful, allowing both enhanced contents of bioactive compounds and extended microbiological shelf-life of “fresh-like” berry juices.

Investigation of injectable drospirenone organogels with regard to their rheology and comparison to non-stabilized oil-based drospirenone suspensions

The objective of this study was to evaluate organogels as potential injectable drug-delivery systems for drospirenone (DRSP). Recently, studies on organogel characterization with focus on the parenteral injection are rarely to find in the literature. DRSP organogels contained the drug suspended in medium-chain triglycerides and were stabilized by various organogelators. The DRSP organogels were assessed in comparison to non-stabilized DRSP microcrystal suspensions (MCSs). Furthermore, rheological properties of the organogels, in particular the elastic modulus (G′), the complex viscosity (η*) and the elasticity, were evaluated with respect to the long-term stability, syringeability/injectability and in vitro release. DRSP organogels showed significantly improved storage stability compared to non-stabilized MCSs with regard to sedimentation and particle growth. Furthermore, all of the DRSP organogels showed shear-thinning behavior. Thus, ejection from syringes was possible by an autoinjector using 23G needles comparable to non-stabilized MCSs. Nevertheless, DRSP organogels exhibited significantly more sustained drug release than non-stabilized MCSs most likely caused by partial recovery of the organogelator structures at 37 °C after destruction. Consequently, DRSP organogels were evaluated to be superior to conventional non-stabilized MCSs. Silica organogels, which provided the highest elasticity, moderate G' and η* and avoided most efficiently particle growth, are slightly more preferable compared to the other DRSP organogels.