Spray-drying Technique Research Articles

A Spray-Dried, Co-Processed Rice Starch as a Multifunctional Excipient for Direct Compression.

A new co-processed, rice starch-based excipient (CS) was developed via a spray-drying technique. Native rice starch (RS) was suspended in aqueous solutions of 10%–15% cross-linked carboxymethyl rice starch (CCMS) and 0.5%–6.75% silicon dioxide (in the form of sodium silicate), before spray drying. The resulting CSs were obtained as spherical agglomerates, with improved flowability. The compressibility study revealed an improved plastic deformation profile of RS, leading to better compaction and tensile strength. The presence of CCMS also ensured a rapid disintegration of the compressed tablets. CS-CCMS:SiO2 (10:2.7), prepared with 10% CCMS, 2.7% silicon dioxide, and 40% solid content, was found to exhibit the best characteristics. Compared to the two commercial DC excipients, Prosolv® and Tablettose®, the flow property of CS-CCMS:SiO2 (10:2.7) was not significantly different, while the tensile strength was 23%: lower than that of Prosolv® but 4 times higher than that of Tablettose® at 196 MPa compression force. The disintegration time of CS-CCMS:SiO2 (10:2.7) tablet (28 s) was practically identical to that of Tablettose® tablet (26 s) and far superior to that of Prosolv® tablet (>30 min). These results show that CSs could potentially be employed as a multifunctional excipient for the manufacturing of commercial tablets by DC.

Rice Bran Protein Powder Production Using Spray Drying Technique: Effect of Temperature, Feed Flowrate and Air Flowrate

.Rice bran is quite a novel subject in the food and pharmaceutical research area. It is the by-product of the rice milling process that is rich in proteins and many other nutrients. However, rice bran is commonly used to feed cattle, also as fertilizer and fuel but not as a source of nutrients for humans. Thus, this study proposes another protein source and explore its production methods for food and supplement industry. This research focuses to produce rice bran protein powder and protein concentration using spray drying technique. Since rice bran protein is used in food consumption, the extraction of protein from rice bran was done using physical extraction method which water as the medium of extraction. The relationship between the spray drying parameter; inlet temperature (130 – 200˚C), feed flowrate (10 – 40%) and air flowrate (225 – 625L/Hr) were investigated based on the OFAT method, As conclusion, spray drying process of rice bran protein powder has the capability to maintain the nutritional value present in the rice bran. Rice bran protein powder could be an alternative source of hypoallergenic plant-based protein supplement to humans in the future with further research.

A Comparison of Spray-Drying and Freeze-Drying for the Production of Stable Silybin Nanosuspensions.

Spray-drying and freeze-drying are effective approaches to improve the long-term stability of nanosuspensions. This research explored the effect of spray-drying and freeze-drying techniques on PVP K30-stabilized silybin nanosuspensions. The morphology was observed by scanning electron microscopy (SEM): The spray-dried sample was spherical, and the freeze-dried samples were rodlike with smooth surfaces. The redispersibility was studied via dynamic light scattering (DLS): The size, PDI, and zeta of the spray-dried sample were 133.27 nm, 0.214, and 24.37 mV, respectively; the size, PDI, and zeta of the freeze-dried sample were 298.70 nm, 0.114, and 20.98 mV, respectively. The in vitro dissolution was studied, and the two dry powders showed a significant increase compared to silybin. The two dried powders had better long-term stability than the liquid starting material. Overall, spray-drying and freeze-drying are appropriate drying methods for the preparation of silybin nanosuspensions with better stability and dissolution velocity.

Spray-drying synthesis of LiMnO2@VXC-72R composite microspheres with excellent electrochemical performance

A facile synergetic strategy is reported for the synthesis of the LiMnO2@VXC-72R composite microspheres by applying spray-drying technique with nanosized LiMnO2 particles as host material and conductive carbon black (VXC-72R) as dispersing agent. In this hybrid structure, LiMnO2 nanoparticles promote the lithium-ion diffusion due to the nanosized diffusion distance, whereas well-distributed VXC-72R suppress the aggregation of LiMnO2 nanoparticles and enhance the electronic conduction. Moreover, the micro-sized spherical morphology with low specific surface area is conducive to reducing the contact area between electrolyte and composite cathode, which inhibit the manganese dissolution. Benefiting from their synergistic effect, the LiMnO2@VXC-72R composite microspheres achieve the maximum discharge capacity of 187.3 mAh g−1 with good cycling stability at 0.1 C. After 50 cycles, the discharge capacity of composite cathode is still maintained at 173.2 mAh g−1, which is significantly higher compared to the primary LiMnO2 particles. Moreover, the LiMnO2@VXC-72R composite microspheres exhibit outstanding rate performance with high discharge capacity.

Significantly enhanced electrochemical properties of LiMn2O4-based composite microspheres embedded with nano-carbon black particles

Herein, we have successfully prepared the LiMn2O4-based composite microspheres embedded with nano-carbon black (VXC-72R) particles by using spray-drying technique with nanosized LiMn2O4 particles as host material and VXC-72R nanoparticles as dispersing agent. For this hybrid composite, LiMn2O4 nanoparticles contribute to the fast diffusion of lithium ions because of nanosized diffusion distance, and well-distributed VXC-72R nanoparticles not only enhance the electronic conductivity but also restrain the aggregation of LiMn2O4 nanoparticles. The low specific surface area of micro-sized composite microspheres can reduce the contact area between cathode material and electrolyte, which help to suppress the manganese dissolution in electrolyte to some extent. Because of the synergistic action of these advantages, the obtained LiMn2O4@VXC-72R composite exhibits high initial discharge capacity of 127.4mAhg−1 with good cycling stability at 0.5°C. After 100 cycles, the discharge capacity of composite cathode still reaches up to 120.1mAhg−1, which is much higher than that of the primary LiMn2O4 particles. Moreover, the LiMn2O4@VXC-72R composite shows excellent high-rate capability and high-temperature performance.

Polysaccharide-based delivery systems for curcumin and turmeric powder encapsulation using a spray-drying process

Curcumin is a hydrophobic polyphenol with a large spectrum of pharmacological functions, such as anti-inflammatory, anticarcinogenic and antioxidant, among others. Due to its chemical instability, the incorporation of curcumin into carrier-based delivery systems has been proposed to improve its stabilization and bioavailability in the human body. The present work suggests the spray-drying technique for the encapsulation of curcumin and turmeric powder (with the active compound curcumin) using the polysaccharides pectin, maltodextrin, inulin and xanthan as encapsulating agents. A product yield between 7.52 and 60.60% was registered for all the microparticles produced: empty, loaded with turmeric powder and loaded with curcumin. Microparticles with a spherical form, rough surface (pectin, maltodextrin and xanthan microparticles) and smooth surface (inulin microparticles) were produced. The fastest core compound release from curcumin- and turmeric powder-loaded microparticles was registered with inulin and maltodextrin, respectively. The most appropriate kinetic model to describe the registered release profiles is the Weibull model.

Metal-Organic Framework Microsphere Formulation for Pulmonary Administration.

Although nanoscaled metal-organic frameworks (nanoMOFs) are promising drug carriers, their appropriate formulation remains almost unexplored and basically restricted to intravenous routes. Lungs, beneficiating from a large absorption surface and low enzymatic presence, are a very attractive target for both local and systemic delivery. However, pulmonary nanoMOF formulation is a pending and defying task. Thus, we propose a pioneer nanoMOF-based microsphere system as a potential platform for pulmonary administration. A biocompatible nanoMOF was successfully encapsulated in mannitol by a simple and continuous spray-drying technique. Upon intratracheal administration to rats, the resulting formulation, exhibiting optimal properties (i.e., homogeneity, size, density, and spray-drying process yield), was able to release the intact nanoMOF carrier uniformly along the lungs, reaching the bronchioles and alveoli.

Magnetically guided targeted delivery of erythropoietin using magnetic nanoparticles: Proof of concept.

The objective of this proof-of-concept study was to demonstrate the targeted delivery of erythropoietin (EPO) using magnetically guided magnetic nanoparticles (MNPs).MNPs consisting of a ferric-ferrous mixture (FeCl3·6H2O and FeCl2·4H2O) were prepared using a co-precipitation method. The drug delivery system (DDS) was manufactured via the spray-drying technique using a nanospray-dryer. The DDS comprised 7.5 mg sodium alginate, 150 mg MNPs, and 1000 IU EPO.Scanning electron microscopy revealed DDS particles no more than 500 nm in size. Tiny particles on the rough surfaces of the DDS particles were composed of MNPs and/or EPO, unlike the smooth surfaces of the only alginate particles. Transmission electron microscopy showed the tiny particles from 5 to 20 nm in diameter. Fourier-transform infrared spectroscopy revealed DDS peaks characteristic of MNPs as well as of alginate. Thermal gravimetric analysis presented that 50% of DDS weight was lost in a single step around 500°C. The mode size of the DDS particles was approximately 850 nm under in vivo conditions. Standard soft lithography was applied to DDS particles prepared with fluorescent beads using a microchannel fabricated to have one inlet and two outlets in a Y-shape. The fluorescent DDS particles reached only one outlet reservoir in the presence of a neodymium magnet. The neurotoxicity was evaluated by treating SH-SY5Y cells in 48-well plates (1 × 10 cells/well) with 2 μL of a solution containing sodium alginate (0.075 mg/mL), MNPs (1.5 mg/mL), or sodium alginate + MNPs. A cell viability assay kit was used to identify a 93% cell viability after MNP treatment and a 94% viability after sodium alginate + MNP treatment, compared with the control. As for the DDS particle neurotoxicity, a 95% cell viability was noticed after alginate-encapsulated MNPs treatment and a 93% cell viability after DDS treatment, compared with the control.The DDS-EPO construct developed here can be small under in vivo conditions enough to pass through the lung capillaries with showing the high coating efficiency. It can be guided using magnetic control without displaying significant neurotoxicity in the form of solution or particles.

Stability of camu‐camu encapsulated with different prebiotic biopolymers

A viable possibility for the best use of bioactive compounds present in camu-camu, fruit native to the Amazonian rainforest, is the preparation of microcapsules using different biopolymers by the spray-drying technique, which would increase the possibilities for innovation in the food industry, as well as facilitate the application in different food matrices. In this context, the chemical, physicochemical, and morphological properties and stability of camu-camu extract (peel and pulp) spray-dried using maltodextrin, inulin, and oligofructose as encapsulating agents were investigated, as well as lyophilized camu-camu extract (CEL). Different relative humidities (22%, 51%, and 75%) and temperatures (25 °C and 45 °C) were evaluated. The moisture, water activity, and solubility values varied from 18.4 to 107.9 g water per kilogram dry powder, 0.06 to 0.27, and 950.80 to 920.28 g microparticles per kilogram of water respectively. Retention of the bioactive compounds varied in the ranges 5.5-7.1 g per kilogram ascorbic acid fresh weight and 7.2-9.0 g per kilogram anthocyanins fresh weight. The increase in temperature and relative humidity during storage provided a significant decrease in the stability of the bioactive compounds for all treatments. However, the CEL presented higher water adsorption kinetics and degradation under all storage conditions, indicating the importance of the use of encapsulating agents. In general, the prebiotic biopolymers used as encapsulating agents in the microencapsulation of extracts of camu-camu by spray-drying presented satisfactory results, suggesting that this technique is an effective strategy to increase the stability of bioactive compounds contained in fruits and vegetables. © 2020 Society of Chemical Industry.

Modification of LiCoO2 through rough coating with lithium lanthanum zirconium tantalum oxide for high-voltage performance in lithium ion batteries

In this study, the spray-drying technique was used to apply a 0.5 at%, 1 at%, and 1.25 at% of lithium lanthanum zirconium tantalum oxide (Li6.75La3Zr1.75Ta0.25O12) powder coating on the surface of lithium cobalt oxide (LiCoO2) cathode materials. Subsequently, these materials were sintered for either 5 or 10 h at 800 °C to obtain LiCoO2 cathode materials with a rough coating. X-ray diffraction, cyclic voltammetry, electrochemical impedance spectroscopy, and differential scanning calorimetry were then conducted to analyze differences in the structure, electrochemical properties, and thermostability of the materials before and after surface modification. The modified LiCoO2 cathodes with Li6.75La3Zr1.75Ta0.25O12 rough coating had more than twice the discharge capacity as the bare LiCoO2 cathode at a high discharge current density when the cutoff voltage ranged from 2.8 to 4.5 V. In addition, 1 at% Li6.75La3Zr1.75Ta0.25O12 coating and 5 h of sintering at 800 °C resulted in the optimal capacity retention of 85.4% after 80 cycles and a slower exothermic reaction than that of the bare LiCoO2 cathode. Thus, rough coating an adequate quantity of Li6.75La3Zr1.75Ta0.25O12 powder on a LiCoO2 cathode mitigated the reaction between the cathode material surface and electrolyte, stabilizing the main structure and enhancing the ionic conductivity and electrochemical characteristics of the material.

Characterization and Dissolution Study of Micellar Curcumin-Spray Dried Powder for Oral Delivery.

IntroductionCurcumin faces a major challenge in clinical use due to its poor aqueous solubility, which affects its bioavailability over oral use. The present study was carried out to overcome this problem.MethodsAn amorphous micellar curcumin-spray dried powder (MC-SDP) with self-assembled casein was prepared by the addition of sucrose as a protectant. The dry powder of curcumin-loaded micelles was obtained by a spray-drying technique in the presence of sucrose as a protectant. The MC-SDP in the form of dry powder was further developed into tablets to investigate the dissolution profile. The physical properties of preformed powder were characterized by differential thermal analysis (DTA), X-ray diffraction (XRD), and scanning electron microscopy (SEM). Quantitative analysis in the form of solutions was analyzed by high-performance liquid chromatography (HPLC).ResultsThe physical properties demonstrated that MC-SDP varies from dented to smoother surfaces as a function of sucrose. Furthermore, melting transitions of curcumin in the form of MC-SDP were broadened in all sample mixtures, as observed in the DTA thermogram. The XRD spectra showed that the sharp and very intense peaks of single curcumin crystalline structure no longer existed in all MC-SDP forms, indicating that the mixtures were amorphous. Moreover, a further dissolution study of MC-SDP showed a significant increase of drug dissolved with the presence of sucrose, where >80% of curcumin from MC-SDP was dissolved within 30 min.ConclusionThe study demonstrated the manufacture of micellar spray-dried powder that would contribute to the development of oral delivery of curcumin.

Microencapsulation of sour cherry oil by spray drying: Evaluation of physical morphology, thermal properties, storage stability, and antimicrobial activity

In this study, sour cherry seed oil (SCSO) loaded gum Arabic (GA)-Maltodextrin (MD) microcapsules were developed by using spray-drying technique. The optimum processing conditions determined using the response surface methodology (RSM) were as follows: a weight ratio of GA to MD (GA:MD composition) of 1:11, a weight ratio of oil to total solid (core-wall ratio) of 20%, and inlet temperature of 195 °C. SCSO powder (SCSOP) was characterized in terms of morphology and size using scanning electron microscopy (SEM), and a laser particle diameter analyzer. The presence of SCSO in GA/MD matrix was confirmed by using Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR). The thermal stability of the SCSOP was assessed using thermogravimetric (TGA) and differential thermal analysis (DTA). Microencapsulation provided a remarkable oxidative stability to SCSOP compared to free sour cherry oil. The antimicrobial potential of the microcapsules were assessed against pathogenic bacteria, yeast and mold.

MOF-Beads Containing Inorganic Nanoparticles for the Simultaneous Removal of Multiple Heavy Metals from Water.

Pollution of water with heavy metals is a global environmental problem whose impact is especially severe in developing countries. Among water-purification methods, adsorption of heavy metals has proven to be simple, versatile, and cost-effective. However, there is still a need to develop adsorbents with a capacity to remove multiple metal pollutants from the same water sample. Herein, we report the complementary adsorption capacities of metal-organic frameworks (here, UiO-66 and UiO-66-(SH)2) and inorganic nanoparticles (iNPs; here, cerium-oxide NPs) into composite materials. These adsorbents, which are spherical microbeads generated in one step by continuous-flow spray-drying, efficiently and simultaneously remove multiple heavy metals from water, including As(III and V), Cd(II), Cr(III and VI), Cu(II), Pb(II), and Hg(II). We further show that these microbeads can be used as a packing material in a prototype of a continuous-flow water treatment system, in which they retain their metal-removal capacities upon regeneration with a gentle acidic treatment. As proof-of-concept, we evaluated these adsorbents for purification of laboratory water samples prepared to independently recapitulate each of two strongly polluted rivers: the Bone (Indonesia) and Buringanga (Bangladesh) rivers. In both cases, our microbeads reduced the levels of all the metal contaminants to below the corresponding permissible limits established by the World Health Organization (WHO). Moreover, we demonstrated the capacity of these microbeads to lower levels of Cr(VI) in a water sample collected from the Sarno River (Italy). Finally, to create adsorbents that could be magnetically recovered following their use in water purification, we extended our spray-drying technique to simultaneously incorporate two types of iNPs (CeO2 and Fe3O4) into UiO-66-(SH)2, obtaining CeO2/Fe3O4@UiO-66-(SH)2 microbeads that adsorb heavy metals and are magnetically responsive.

Unexpected burning rate independence of composite propellants on the pressure by fine interfacial control of fuel/oxidizer

In this paper, micro-spherical Al@PDA@RDX composites with fine interfacial control have been fabricated by spray-drying technique, where poly-dopamine (PDA) is employed as a binding layer. These composites have been applied in HTPB/AP/RDX/Al propellants, which have the same theoretical formulation and hence identical specific impulse (Isp). However, these propellants differ in the interfacial structure due to different ways of assembling the ingredients, resulting in significant changes in their combustion performance. The thermal reactivity, burning rate, flame structure and the morphology of condensed combustion products (CCPs) of the prepared propellants have been investigated comprehensively. It has been shown that the pressure exponent (1–4 MPa) can be decreased from 0.236 to 0.024 (10 times lower) by the fine interfacial control, with more than 500 °C increase in flame temperature and 45.5% drop-off in the flame stand-off distance. In addition, the CCPs size distributions of the propellants have shown the enhanced interfacial interaction from Al@PDA@RDX composites can greatly inhibit the large-sized agglomeration of Al particles during the burning process.

Modulation of Pharmaceutical and Pharmacokinetic Attributes of Curcumin Encapsulated in Chitosan Using Spray Drying Technique

The present study is designed to formulate and characterize Curcumin (CUR) loaded Chitosan nanoparticles by ionic cross linking using TPP by employing spray drying technique to enhance the aqueous solubility, hence oral bio availability of Curcumin. Curcumin is very sparingly aqueous soluble, unstable in alkaline conditions and gets eliminated faster, resulting in poor bio availability. Curcumin in alcohol was used as drug loading solution. Tween 80 served as nano emulsifier and stabilizer. EE of optimized formulation F6 was found to be 98.5 ± 0.16 %. This formulation has an average particle size of 25 ± 0.1 nm. The Zeta potential of the formulation is -200 mV. FTIR results revealed the absence of characteristic CUR peak in Curcumin Chitosan nanoparticles implying the successful incorporation of CUR into the Chitosan matrix. DSC thermograms witnessed that the crystalline form of CUR is transformed into amorphous form, having better dissolution and stability profile. SEM imaging of the nanosuspension formulation showed the topological features of the prepared nanoparticles. The nanoparticles were more spherical, discrete and homogeneous. % cumulative drug release studies exhibited very less drug release in Simulated Gastric Fluid (SGF- 3.97 %) and Simulated Intestinal Fluid (SIF - 4.2 %) exhibiting sustained release. Pure Curcumin showed burst release of approximately 95 % in 2 h in SGF with a decline in the concentration after 2 h in SIF due to significantly increased degradation in the alkaline conditions. The oral bioavailability (AUC) of Curcumin in female wistar rats increased 11-times following ingestion of Curcumin nanosuspension in comparison with conventional Curcumin suspension. The maximum concentration Cmax of 1034 ± 96 ng / ml for nanosuspension and 94 ± 9.4 ng / ml for Curcumin suspension and was observed at tmax of 2 h for both nanosuspension and suspension.

Inhalable Lactoferrin/Chondroitin-Functionalized Monoolein Nanocomposites for Localized Lung Cancer Targeting.

Localized drug delivery to lung cancer can overcome the limitations of systemic nanocarriers including low drug amounts reaching lung tissues and severe off-target toxicity. The current work presented novel inhalable nanocomposites as noninvasive platforms for lung cancer therapy. Nanoparticulate liquid crystals (LCNPs) based on monoolein were developed for synergistic co-encapsulation of the cytotoxic chemotherapeutic drug, pemetrexed, and the phytoherbal drug, resveratrol (PEM-RES-LCNPs). For active tumor targeting, lactoferrin (LF) and chondroitin sulfate (CS), natural polymers with intrinsic tumor-targeting capabilities, were exploited to functionalize the surface of LCNPs using a layer-by-layer (LbL) self-assembly approach. To maximize their deep lung deposition, LF/CS-coated PEM-RES-LCNPs were then microencapsulated within various carriers to obtain inhalable nanocomposites via spray-drying techniques. The inhalable dry powder nanocomposites prepared using a mannitol-inulin-leucine (1:1:1 wt) mixture displayed superior in vitro aerosolization performance (2.72 μm of MMAD and 61.6% FPF), which ensured deep lung deposition. In lung cancer-bearing mice using urethane as a chemical carcinogen, the inhalable LF/CS-coated PEM-RES-LCNP nanocomposites showed superior antitumor activity as revealed by a considerable decrease of the average lung weight, reduced number and diameter of cancerous lung foci, decreased expression of VEGF-1, and increased expression of active caspase-3 as well as reduced Ki-67 expression compared to the spray-dried free PEM/RES powder mixture and positive control. Moreover, the in vivo fluorescence imaging confirmed successful lung deposition of the inhalable nanocomposites. Conclusively, the inhalable liquid crystalline nanocomposites elaborated in the current work could open new avenues for noninvasive lung cancer treatment.

Influence of levodropropizine and hydroxypropyl-β-cyclodextrin association on the physicochemical characteristics of levodropropizine loaded in hydroxypropyl-β-cyclodextrin microcontainers: Formulation and in vitro characterization.

Poorly water-soluble drugs do not dissolve well in aqueous-based gastrointestinal fluid; therefore, they are not well absorbed. Thus, employing a suitable solubility enhancing technique is necessary for such a drug. Drug/HP‑β‑CD complexation is a promising way to improve solubility and dissolution of a poorly water-soluble drug. Levodropropizine was used as a model drug in this study. The purpose of this research was to enhance the aqueous solubility and dissolution rate of levodropropizine by employing the inclusion complexation technique. A microparticle formulation was prepared from levodropropizine and hydroxypropyl-β-cyclodextrin (HP‑β‑CD) in a 1:1 molar ratio through the spray-drying technique. The host-guest relationship between levodropropizine and HP‑β‑CD was also investigated using the molecular docking computational methodology. The aqueous solubility and dissolution rate of levodropropizine in formulations were assessed and compared with those of the drug alone. X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR) were applied for the solid-state characterization of the prepared samples. According to the research outcomes, the levodropropizine/HP‑β‑CD formulation had enhanced the aqueous solubility (351.12 ±13.26 vs 92.76 ±5.00 mg/mL) and dissolution rate (97.83 ±3.36 vs 3.12 ±1.76% in 10 min) of levodropropizine, compared to the plain drug powder. The levodropropizine/ HP‑β‑CD formulation had converted the crystalline drug into its amorphous counterpart. Furthermore, no covalent interaction was found to exist between levodropropizine and HP‑β‑CD. The spray-dried particles were discrete. Each particle had a shriveled appearance. The levodropropizine/HP‑β‑CD formulation is, therefore, recommended for the more effective administration of levodropropizine through the oral route.

Spray-drying encapsulation of protein hydrolysates and bioactive peptides: Opportunities and challenges

In the recent years, extensive research is under way about the use of natural bioactive compounds and production of functional foods to increase community health and reduce the risk of various food-related diseases. Among different bioactive compounds, the health benefits of peptides and protein hydrolysates make these compounds as nutraceutical food-additives in the formulation of functional foods. But due to physicochemical instability, hygroscopicity and bitterness, direct use of the bioactive peptides in food formulations is difficult. Encapsulation of these compounds in different carriers is one of the most common techniques to overcome the mentioned disadvantages. Among different techniques of encapsulation, spray-drying is the most economical and flexible process for reduction of hygroscopicity, masking of unpleasant-flavors and increasing the stability of bioactive peptides. In this study, the health benefits of peptides and hydrolysates, their disadvantages and applications of microencapsulation by spray-drying technique have been discussed. Also, the most recent results concerning the effect of encapsulation process with different carriers on physicochemical properties, physical and antioxidant stability, masking of bitterness and morphological characteristics of spray-dried powders loaded with bioactive peptides have been investigated.

Insecticidal activity of spray dried microencapsulated essential oils of Rosmarinus officinalis and Zataria multiflora against Tribolium confusum

Rosmarinus officinalis and Zataria multiflora (Lamiaceae) essential oils (EOs) contain components with insecticidal properties that can be used as pesticides for stored product pests. In the present study, they were encapsulated in octenyl succinic anhydride (OSA) - starch in order to test their insecticidal activity against Tribolium confusum. First an oil-in-water emulsion was prepared and afterwards, it was dried by spray-drying technique. The emulsions were characterized regarding particle size (461–854 nm), stability and encapsulated oil efficiency (68–88%). Also, solid formulations were characterized by particle size (8.29–11.35 μm), encapsulation efficiency (5–52%) and water activity (0.19–0.26). Further, the release rate at storage conditions (at 27 ± 3 °C and 70–75% relative humidity in the dark) was measured over a period of 40 days. The insecticidal activity against T. confusum was determined by specific bioassays performed at 27 ± 3 °C temperature and 70–75% relative humidity in the dark. Five concentrations were used for estimation of fumigant toxicity of rosemary and Zataria oils after 72 h exposure in adult beetles. Fumigant toxicity results revealed that microencapsulated oils were more effective than non-formulated oils against beetles in long time. Similarly, it was demonstrated that microencapsulation of the essential oils increases their persistence: non-formulated oils have not insecticidal activity after 15 days of the storage period, whereas at the same period, the mortality rate against T. confusum of rosemary and Zataria microencapsulated oils was 46.6 and 35.5%, respectively.

Formulation of Dry Powder Inhaler of Anti-tuberculous Drugs Using Spray Drying Technique and Optimization Using 23 Level Factorial Design Approach

Background: Targeting anti-tubercular therapeutics to alveolar macrophages using microparticles technology mainly focuses on increasing local concentrations of therapeutics and potentially reducing the frequency of dosing requirements. Rifampicin (RIF), Ofloxacin (OFX) and Ethambutol (ETH) combination show synergism. Objective: In light of the above facts, the focus of the present study was to develop and characterize novel Dry powder Inhaler formulation incorporating novel drug combination as a pulmonary delivery for the effective eradication of Tuberculosis. Method: Biodegradable microparticles containing RIF, OFX and ETH were prepared by a spray drying technique using PLGA polymer through the critical process as well as polymer attributes were screened and optimized using 23 factorial design. The identified critical process parameters (CPP’s) viz. Inlet temperature, Aspiration rate, and feed rate were selected as independent variables while percentage yield, percentage entrapment efficiency, and particle size were selected as a response. The formulated microparticles were evaluated for particle size, drug-polymer compatibility study, aerodynamic behavior, morphology, particle size distribution, crystallinity, residual solvent content, in-vitro drug release study, and stability study. Results: By choosing the optimum spray drying conditions maximum yield of 73%, entrapment efficiency of 86% and particle size of 1.4 μm was attained of the optimized batch. Thus the results revealed that spherical microparticles are suitable for inhalation and sustained release for 12 h. Conclusion: The successful formulation and evaluation of dry powder could be used as an enhanced therapeutic alternative of the standard oral anti-tubercular regimen, rescuing oral dosing, shortening drug regimen and limiting toxicity. This will ultimately improve patient compliance and diminish the prevalence of MDR resistance.