Displaying publications 21 - 40 of 90 in total

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  1. Fulltext Comparison of energy and performance from biodegradation of freeze dried and spray dried Algae biomass
    Muhamad Haikal Zainal, Khairul Baqir Alkhair Khairul Amin, Oskar Hasdinor Hassan, Sharifah Aminah Syed Mohamad, Abd Malik Marwan Ali, Fathiah Abdullah, et al.
    Pertanika Journal of Science & Technology, 2017;25(103):53-62.
    MyJurnal
    Many kinds of substrates have been used to investigate bioelectricity production with Microbial Fuel Cell (MFC). Dry algae biomass has the highest maximum power density compared to other substrates due to high carbon sources from its lipid. However, the bacterial digestion of algae biomass is not simple because of the complexity and strength of the algal cell wall structure. An algae biomass extraction is needed to break the cell wall structure and facilitate digestion. Spray drying method is commonly used in highvalue products but may degrade some algal components which are crucial for microbial degradation in MFC, while the freeze-drying method is able to preserve algal cell constituents. The MFC was fed with freeze dried and spray dried algae biomass to produce energy and determine the degradation efficiency. Results showed the average voltage generated was 739 mV and 740 mV from freeze dried and spray dried algae biomass, respectively. The maximum power density of freeze dried algae biomass is 159.9 mW/m2 and spray dried algae biomass is 152.3 mW/m2. Freeze dried algae biomass has 54.2% of COD removal and 28.4% of Coulombic Efficiency while spray dried algae biomass has 50.1% of COD removal and 24.9% of Coulombic Efficiency.
    Matched MeSH terms: Freeze Drying
  2. Fulltext Establishing freeze drying process for cortical and cancellous bone allograft cubes
    Ariffin, A.A., Chan, H.H., Yusof, N., Mohd, S., Ng, W.M., Mansor A.
    JUMMEC, 2019;22(1):66-71.
    MyJurnal
    Freeze drying is a dehydration method to dry bone under freezing environment, enabling removal of water
    with no or minimial effects on bone strength and durability. Larger size bones obviously require longer freeze
    drying time to reduce water content to the required level for long term storage at room temperature. For small
    size bone cubes or chips, it is a normal practice to pool cortical and cancellous bones for freeze drying. The
    study was aimed at determining if different type of bones of the same size influence the drying time. Human
    bone cubes of 10 mm x 10 mm x 10 mm were prepared from cortical bone of tibiae and cancellous bone from
    femoral heads. The bone cubes were freeze dried to reduce water content to less than 6%. Moisture content
    was monitored using gravimetric method.Weight and density of cortical bone were significantly higher than
    cancellous bone despite of having similar small size (p
    Matched MeSH terms: Freeze Drying
  3. Effect of different drying methods on the morphology, crystallinity, swelling ability and tensile properties of nata de coco
    Norhayati Pa'e, Nur Idayu Abd Hamid, Norzieana Khairuddin, Khairul Azly Zahan, Kok FS, Bazlul Mobin Siddique, et al.
    Sains Malaysiana, 2014;43:767-773.
    Nata de coco or bacterial cellulose produced by Acetobacter xylinum is a unique type of biocellulose. It contains more than 90% of water. Dried nata was preferred compared to wet form since it is more convenient and portable with stable properties. Therefore, drying process is necessary in order to produce dried nata de coco. Drying method is a key factor that influenced the properties of dried nata de coco produced. The aim of this study was to investigate the effect of different drying methods on morphology, crystallinity, swelling ability and tensile strength of dried nata de coco. Nata de coco samples were dried using three physical drying methods such as oven, tray dryer or freeze dryer until it achieved 3-5% moisture content. Obviously, the three drying techniques produced web-like structured nata de coco and quite similar crystallinity which was in range between 87 and 89%. Freeze dried sample showed the largest swelling capacity and tensile strength which was found to be 148 MPa. Different drying method gave different properties of nata de coco. Therefore, the present work proposed the most suitable drying method can be utilized based on the properties of end product needed.
    Matched MeSH terms: Freeze Drying
  4. Development of a novel ionic liquid-curcumin complex to enhance its solubility, stability, and activity
    Chowdhury MR, Moshikur RM, Wakabayashi R, Tahara Y, Kamiya N, Moniruzzaman M, et al.
    Chem Commun (Camb), 2019 Jun 11.
    PMID: 31184357 DOI: 10.1039/c9cc02812a
    We report a one-step emulsification and rapid freeze-drying process to develop a curcumin-ionic liquid (CCM-IL) complex that could be readily dispersed in water with a significantly enhanced solubility of ∼8 mg mL-1 and half-life (t1/2) of ∼260 min compared with free CCM (solubility ∼30 nM and t1/2 ∼ 20 min). This process using an IL consisting of a long chain carbon backbone as a surfactant, may provide an alternative way of enhancing the solubility of poorly water-soluble drugs.
    Matched MeSH terms: Freeze Drying
  5. The effect of drying methods on the physicochemical and antioxidant properties of Bintangor orange (Citrus nobilis) powders
    Phing PL, Abdullah A, Sin CL, Foong SCY
    Acta Sci Pol Technol Aliment, 2022 2 18;21(1):111-122.
    PMID: 35174693 DOI: 10.17306/J.AFS.0901
    BACKGROUND: Bintangor oranges are a mandarin species that is abundant in vitamin C and beta-carotene. However, due to its short shelf life, the fresh fruit can be converted into powder form, which is comparatively more stable.

    METHODS: This study compares the effects of spray drying, freeze drying, drum drying, vacuum oven drying, and convection oven drying on the physicochemical properties of Bintangor orange powder, including vitamin C and total carotenoid content. The physicochemical properties analyzed for the powders were color analysis, moisture content, water activity, hygroscopicity, degree of caking, wettability, flowability, water solubility index, and bulk density.

    RESULTS: Our results showed that freeze dried and convection oven dried powders retained their color so that the powder was the same as the original puree. All powders used in this showed an acceptable moisture content level, with a range of 2.11–2.31%. Spray dried and drum dried powders had the lowest value of moisture content and water activity. Moreover, spray dried powders showed the lowest value in hygroscopicity and bulk density and took the shortest time to wet the powder. The highest solubility and flowability properties were 12.99%, 0.39 g/mL, 18.39 s, 96.08%, and 19.17°, respectively. However, the freeze drying method retained the highest value for both nutritional pigments of vitamin C and total carotenoid content, 18.31 mg/g and 91.32 μg/g, respectively.

    CONCLUSIONS: Freeze drying is the most suitable drying method with favorable powder properties compared to spray drying, drum drying, vacuum oven drying and convection oven drying.

    Matched MeSH terms: Freeze Drying
  6. Fulltext Effect of drying method on functional properties and antioxidant activities of chicken skin gelatin hydrolysate
    Wan Omar WH, Sarbon NM
    J Food Sci Technol, 2016 Nov;53(11):3928-3938.
    PMID: 28035148 DOI: 10.1007/s13197-016-2379-5
    The aim of this study is to investigate the functional and antioxidant properties of chicken skin gelatin hydrolysate (CSGH) as affected by the drying method used in the preparation of gelatin (freeze-dried and vacuum dried). CSGH obtained from freeze-dried gelatin showed better functional properties such as emulsifying activity index (EAI), water holding and oil binding capacity at different pH compared to CSGH produced from vacuum dried gelatin. Meanwhile, the CSGH of the vacuum dried gelatin exhibited a better emulsifying stability index (ESI), foaming capacity and stability. CSGH from freeze-dried gelatin showed better antioxidant, DPPH radical scavenging and metal chelating activity.
    Matched MeSH terms: Freeze Drying
  7. Fulltext Anthocyanins from Hibiscus sabdariffa, Melastoma malabathricum and Ipomoea batatas and its color properties
    Aishah, B., Nursabrina, M., Noriham, A., Norizzah, A.R., Mohamad Shahrimi, H.
    International Food Research Journal, 2013;20(2):827-834.
    MyJurnal
    There are many factors influencing the stability and color variation of natural colorant anthocyanin and pH is among the most significant factor. This study aims to determine the stability of the anthocyanins in freeze-dried Hibiscus sabdariffa, Melastoma malabathricum and Ipomoea batatas in various acidic pH (pH 2.0, 2.5, 3.0, 3.5, 4.0 and 4.5). Total monomeric anthocyanin, degradation index, color density and percent polymeric color were analyzed to determine anthocyanins degradation and their color variations. Among the samples, H.sabdariffa contain the highest monomeric anthocyanins (163.3 mg/L) followed by M. malabathricum (49.9 mg/L) and the lowest is I.batatas (13.8 mg/L). Monomeric anthocyanins from I.batatas were found to be very stable and not affected by changes in pH than in H. sabdariffa and M. malabathricum. However, degradation index (DI) of H. sabdariffa was the lowest with value of 0.365 ± 0.049 at pH 3.5. The lowest percentage of polymeric color (4.94 ± 0.64) was also shown by H. sabdariffa at pH 2.5 and maintained a deep red color with increasing pH indicating higher color stability compared to M. malabathricum and I. batatas. Overall, natural pigment in H. sabdariffa was found to be the most stable in both monomeric anthocyanin content and chromaticity properties. These results provided information that will further proven the potential usage of H. sabdariffa, M. malabathricum and I. batatas as natural coloring agents to replace the synthetic colorant in food and beverage industries.
    Matched MeSH terms: Freeze Drying
  8. Omnidirectional Shape Memory Effect via Lyophilization of PEG Hydrogels
    Chen D, Xia X, Wong TW, Bai H, Behl M, Zhao Q, et al.
    Macromol Rapid Commun, 2017 Apr;38(7).
    PMID: 28196300 DOI: 10.1002/marc.201600746
    Device applications of shape memory polymers demand diverse shape changing geometries, which are currently limited to non-omnidirectional movement. This restriction originates from traditional thermomechanical programming methods such as uniaxial, biaxial stretching, bending, or compression. A solvent-modulated programming method is reported to achieve an omnidirectional shape memory behavior. The method utilizes freeze drying of hydrogels of polyethylene glycol networks with a melting transition temperature around 50 °C in their dry state. Such a process creates temporarily fixed macroporosity, which collapses upon heating, leading to significant omnidirectional shrinkage. These shrunken materials can swell in water to form hydrogels again and the omnidirectional programming and recovery can be repeated. The fixity ratio (R f ) and recovery ratio (R r ) can be maintained at 90% and 98% respectively upon shape memory multicycling. The maximum linear recoverable strain, as limited by the maximum swelling, is ≈90%. Amongst various application potentials, one can envision the fabrication of multiphase composites by taking advantages of the omnidirectional shrinkage from a porous polymer to a denser structure.
    Matched MeSH terms: Freeze Drying
  9. Effects of processing and gamma radiation on mechanical properties and organic composition of frozen, freeze-dried and demineralised human cortical bone allograft
    Mansor A, Ariffin AF, Yusof N, Mohd S, Ramalingam S, Md Saad AP, et al.
    Cell Tissue Bank, 2023 Mar;24(1):25-35.
    PMID: 35610332 DOI: 10.1007/s10561-022-10013-9
    Bone processing and radiation were reported to influence mechanical properties of cortical bones due in part to structural changes and denaturation of collagen composition. This comparative study was to determine effects of bone processing on mechanical properties and organic composition, and to what extent the radiation damaging after each processing. Human femur cortical bones were processed by freezing, freeze-drying and demineralisation and then gamma irradiated at 5, 15, 20, 25 and 50 kGy. In the compression test, freeze drying significantly decreased the Young's Modulus by 15%, while demineralisation reduced further by 90% (P 
    Matched MeSH terms: Freeze Drying
  10. Effects of encapsulation on the viability of potential probiotic Lactobacillus plantarum exposed to high acidity condition and presence of bile salts
    Tee WF, Nazaruddin R, Tan YN, Ayob MK
    Food Sci Technol Int, 2014 Sep;20(6):399-404.
    PMID: 23774606 DOI: 10.1177/1082013213488775
    This study investigated the survival of encapsulated potential probiotic Lactobacillus plantarum which isolated from fermented cocoa beans. κ-Carrageenan was used to encapsulate the probiotic. Encapsulation techniques such as emulsification, freeze-drying or extrusion were adopted to encapsulate the probiotic. Freeze-drying and extrusion methods showed higher (p 
    Matched MeSH terms: Freeze Drying*
  11. Characterization and optimization of lyophilization and storage conditions of Leech saliva extract from the tropical leech Hirudinaria manillensis
    Abdualkader AM, Ghawi AM, Alaama M, Awang M, Merzouk A
    Pak J Pharm Sci, 2013 May;26(3):525-35.
    PMID: 23625426
    The medicinal Malaysian leeches have been used in traditional medicine to treat many different ailments. In this study, leech saliva extract (LSE) was collected from the medicinal Malaysian leech Hirudinaria manillensis. Gel electrophoresis of LSE was carried out to estimate the peptide and protein molecular weights of its content. Results showed that LSE contains more than 60 peptides and proteins with molecular masses ranging from 1.9-250kDa. Thrombin time assay in vitro was employed to assess the collected LSE antithrombin activity. First, to study its stability, LSE was lyophilized under the following different conditions: pre-freezing temperature, type of container and lyophilization cycle. Pre-freezed LSE sample at -20°C and lyophilized for 24 hours retained about 100-95% of its original biological activities. Second, the LSE antithrombin activity was monitored for a period of six months. Storage temperature, type of the container and photosensitivity effects on antithrombin activity of the lyophilized (solid state) and non-lyophilized (liquid state) were investigated. Results showed that storage temperature drastically affected the biological activity of LSE with -20 °C as the optimum temperature. Samples stored at ambient temperature and +4 °C were light photosensitive and adversely affected when stored in polypropylene tubes. Lyophilized samples were more stable than non-lyophilized ones over the period of study. To sum up, in order to have a biologically active stock of LSE, it has to be lyophilized for no more than 24 hours following freezing at -20°C and has to be stored at -20°C in glass tubes protected from light.
    Matched MeSH terms: Freeze Drying/methods
  12. Fulltext Optimization of freeze drying conditions for purified pectinase from mango (Mangifera indica cv. Chokanan) peel
    Mehrnoush A, Mustafa S, Yazid AM
    Int J Mol Sci, 2012;13(3):2939-50.
    PMID: 22489134 DOI: 10.3390/ijms13032939
    Response surface methodology (RSM) along with central composite design (CCD) was applied to optimize the freeze drying conditions for purified pectinase from mango (Mangifera indica cv. Chokanan) peel. The effect of pectinase content (-2.66, 62.66 mg/mL), Arabic gum (-1.21, 10.21%, w/v), and maltodextrin (0.73, 7.26%, w/v) as independent variables on activity, yield, and storage stability of freeze-dried enzyme was evaluated. Storage stability of pectinase was investigated after one week at 4 °C and yield percentage of the enzyme after encapsulation was also determined. The independent variables had the most significant (p < 0.05) effect on pectinase activity and yield of the enzyme. It was observed that the interaction effect of Arabic gum and maltodextrin improved the enzymatic properties of freeze-dried pectinase. The optimal conditions for freeze-dried pectinase from mango peel were obtained using 30 mg/mL of pectinase content, 4.5 (%, w/v) of Arabic gum, and 4 (%, w/v) of maltodextrin. Under these conditions, the maximum activity (11.12 U/mL), yield (86.4%) and storage stability (84.2%) of encapsulated pectinase were achieved.
    Matched MeSH terms: Freeze Drying/methods*
  13. Effect of processing methods on xylitol-starch base co-processed adjuvant for orally disintegrating tablet application
    Bin LK, Helaluddin ABM, Islam Sarker MZ, Mandal UK, Gaurav A
    Pak J Pharm Sci, 2020 Mar;33(2):551-559.
    PMID: 32276897
    Orally disintegrating tablet (ODT) is a friendly dosage form that requires no access to water and serves as a solution to non-compliance. There are many co-processed adjuvants available in the market. However, there is no single product possesses all the ideal characteristics such as good compressibility, fast disintegration and good palatability for ODT application. The aim of this research was to produce a xylitol-starch base co-processed adjuvant which is suitable for ODT application. Two processing methods namely wet granulation and freeze drying were used to compare the characteristics of co-processed adjuvant comprising of xylitol, starch and crospovidone XL-10 mixed at various ratios. The co-processed excipients were compressed into ODT and physically characterized for powder flow, particle size, hardness, thickness, weight, friability, in-vitro disintegration time and in-situ disintegration time, lubricant sensitivity, dilution potential, Fourier transform infrared spectroscopy, scanning electronic microscopy and x-ray diffraction analysis. Formulation F6 was selected as the optimum formulation due to the fastest in-vitro (135.33±11.52 s) and in-situ disintegration time (88.67±13.56s) among all the formulations (p<0.05). Increase in starch component decreases disintegration time of ODT. The powder flow fell under the category of fair flow. Generally, it was observed that freeze drying method produced smaller particle size granules compared to wet granulation method. ODT produced from freeze drying method had shorter disintegration time compared to ODT from wet granulation batch. In conclusion, a novel co-processed excipient comprised of xylitol, starch and crospovidone XL-10, produced using freeze drying method with fast disintegration time, good compressibility and palatability was developed and characterized. The co-processed excipient is suitable for ODT application.
    Matched MeSH terms: Freeze Drying/methods
  14. Approach to preserve phenolics in Thunbergia laurifolia leaves by different drying treatments
    Oh HKF, Siow LF, Lim YY
    J Food Biochem, 2019 07;43(7):e12856.
    PMID: 31353691 DOI: 10.1111/jfbc.12856
    Different drying methods and blanching were investigated as to their effects on antioxidant and oxidase activities of Thunbergia laurifolia leaves. Results showed that oven-drying had the highest degradation of total phenolic content (TPC) and antioxidant activity at >85%, while freeze-drying had the lowest at <20%. However, inactivation of oxidase enzymes by blanching at 100°C resulted in a lesser decrease in TPC for oven-drying at 50 and 100°C (51% and 65%, respectively), indicating the importance of inactivating the oxidase enzymes for lower degradation of phenolics on drying. The high-performance liquid chromatography analysis showed that its major antioxidant, rosmarinic acid, degraded tremendously in the presence of oxidase enzymes, but only degraded slightly upon inactivation of oxidase enzymes. Hence, this work showed that by controlling the enzymatic activity, the preservation of phenolics with specific bioactivity in herbal tea leaves can be achieved. PRACTICAL APPLICATIONS: Thunbergia laurifolia leaves have been frequently consumed in the form of a tea or pill due to its medicinal properties. Processing of fresh herbal plant leaves by drying is required to preserve antioxidant phenolic compounds and quality of the plant leaves. Although the drying effects on the antioxidant properties have been studied, the factors that cause the change in properties have not been investigated in-depth. Controlling the factors that affect the phenolic content can help to preserve the beneficial antioxidants when processing the leaves by drying. The result of this study will be of relevance and beneficial to the herbal tea industry.
    Matched MeSH terms: Freeze Drying/methods
  15. Influence of freeze-drying and spray-drying preservation methods on survivability rate of different types of protectants encapsulated Lactobacillus acidophilus FTDC 3081
    Tang HW, Abbasiliasi S, Murugan P, Tam YJ, Ng HS, Tan JS
    Biosci Biotechnol Biochem, 2020 Sep;84(9):1913-1920.
    PMID: 32448058 DOI: 10.1080/09168451.2020.1770572
    The aims of this study were to compare the effectiveness of different drying methods and to investigate the effects of adding a series of individual protectant such as skim milk, sucrose, maltodextrin, and corn starch for preserving Lactobacillus acidophilus FTDC 3081 cells during spray and freeze-drying and storage at different temperatures. Results showed a remarkable high survival rate of 70-80% immediately after spray- and freeze-drying in which the cell viability retained at the range of 109 to 1010 CFU/mL. After a month of storage, maltodextrin showed higher protective ability on both spray- and freeze-dried cells as compared to other protective agents at 4°C, 25°C, and 40°C. A complete loss in viability of spray-dried L. acidophilus FTDC 3081 was observed after a month at 40°C in the absence of protective agent.
    Matched MeSH terms: Freeze Drying*
  16. Enhancement of viability of a probiotic Lactobacillus strain for poultry during freeze-drying and storage using the response surface methodology
    Khoramnia A, Abdullah N, Liew SL, Sieo CC, Ramasamy K, Ho YW
    Anim Sci J, 2011 Feb;82(1):127-35.
    PMID: 21269371 DOI: 10.1111/j.1740-0929.2010.00804.x
    A rotatable central composite design (CCD) was used to study the effect of cryoprotectants (skim milk, sucrose and lactose) on the survival rate of a probiotic Lactobacillus strain, L. reuteri C10, for poultry, during freeze-drying and storage. Using response surface methodology, a quadratic polynomial equation was obtained for response value by multiple regression analyses: Y = 8.59546-0.01038 X(1)-0.09382 X(2)-0.07771 X(3)-0.054861 X(1)(2)-0.04603 X(3)(2)-0.10938 X(1)X(2). Based on the model predicted, sucrose exerted the strongest effect on the survival rate. At various combinations of cryoprotectants, the viability loss of the cells after freeze-drying was reduced from 1.65 log colony forming units (CFU)/mL to 0.26-0.66 log CFU/mL. The estimated optimum combination for enhancing the survival rate of L. reuteri C10 was 19.5% skim milk, 1% sucrose and 9% lactose. Verification experiments confirmed the validity of the predicted model. The storage life of freeze-dried L. reuteri C10 was markedly improved when cryoprotectants were used. At optimum combination of the cryoprotectants, the survival rates of freeze-dried L. reuteri C10 stored at 4°C and 30°C for 6 months were 96.4% and 73.8%, respectively. Total viability loss of cells which were not protected by cryoprotectants occurred after 12 and 8 weeks of storage at 4°C and 30°C, respectively.
    Matched MeSH terms: Freeze Drying*
  17. Effect of freeze-thaw cycles pretreatment on the vacuum freeze-drying process and physicochemical properties of the dried garlic slices
    Feng Y, Ping Tan C, Zhou C, Yagoub AEA, Xu B, Sun Y, et al.
    Food Chem, 2020 Sep 15;324:126883.
    PMID: 32344350 DOI: 10.1016/j.foodchem.2020.126883
    Freeze-thaw cycles (FTC) pretreatment was employed before the vacuum freeze-drying of garlic slices, aimed at improving the drying process and the quality of the end product. Cell viability, water status, internal structure, flavor, chemical composition and thermogravimetric of garlic samples were evaluated. The results indicated that FTC pretreatment reduced the drying time (22.22%-33.33%) and the energy consumption (14.25%-15.50%), owing to the water loss, the increase in free water, and the formation of porous structures. The FTC pretreatment improved thermal stability, flavor and chemical composition content of dried products. The antioxidant activity of polysaccharides extracted from FTC pretreated dried products was higher than that of the unpretreated dried product due to the reduction in polysaccharide molecular weight. This research could pave a route for future production of dried garlic slices having good quality by using the FTC pretreatment, with lower energy consumption and shorter drying time.
    Matched MeSH terms: Freeze Drying*
  18. Cell viability of microencapsulated Bifidobacterium animalis subsp. lactis under freeze-drying, storage and gastrointestinal tract simulation conditions
    Shamekhi F, Shuhaimi M, Ariff A, Manap YA
    Folia Microbiol (Praha), 2013 Mar;58(2):91-101.
    PMID: 22843029 DOI: 10.1007/s12223-012-0183-9
    The purpose of this study was to improve the survival of Bifidobacterium animalis subsp. lactis 10140 during freeze-drying process by microencapsulation, using a special pediatric prebiotics mixture (galactooligosaccharides and fructooligosaccharides). Probiotic microorganisms were encapsulated with a coat combination of prebiotics-calcium-alginate prior to freeze-drying. Both encapsulated and free cells were then freeze-dried in their optimized combinations of skim milk and prebiotics. Response surface methodology (RSM) was used to produce a coating combination as well as drying medium with the highest cell viability during freeze-drying. The optimum encapsulation composition was found to be 2.1 % Na-alginate, 2.9 % prebiotic, and 21.7 % glycerol. Maximum survival predicted by the model was 81.2 %. No significant (p > 0.05) difference between the predicted and experimental values verified the adequacy of final reduced models. The protection ability of encapsulation was then examined over 120 days of storage at 4 and 25 °C and exposure to a sequential model of infantile GIT conditions including both gastric conditions (pH 3.0 and 4.0, 90 min, 37 °C) and intestinal conditions (pH 7.5, 5 h, 37 °C). Significantly improved cell viability showed that microencapsulation of B. lactis 10140 with the prebiotics was successful in producing a stable symbiotic powdery nutraceutical.
    Matched MeSH terms: Freeze Drying*
  19. Application of freeze-drying technology in manufacturing orally disintegrating films
    Liew KB, Odeniyi MA, Peh KK
    Pharm Dev Technol, 2016;21(3):346-53.
    PMID: 25597618 DOI: 10.3109/10837450.2014.1003657
    Freeze drying technology has not been maximized and reported in manufacturing orally disintegrating films. The aim of this study was to explore the freeze drying technology in the formulation of sildenafil orally disintegrating films and compare the physical properties with heat-dried orally disintegrating film. Central composite design was used to investigate the effects of three factors, namely concentration of carbopol, wheat starch and polyethylene glycol 400 on the tensile strength and disintegration time of the film. Heat-dried films had higher tensile strength than films prepared using freeze-dried method. For folding endurance, freeze-dried films showed improved endurance than heat-dried films. Moreover, films prepared using freeze-dried methods were thicker and had faster disintegration time. Formulations with higher amount of carbopol and starch showed higher tensile strength and thickness whereas formulations with higher PEG 400 content showed better flexibility. Scanning electron microscopy showed that the freeze-dried films had more porous structure compared to the heat-dried film as a result of the release of water molecule from the frozen structure when it was subjected to freeze drying process. The sildenafil film was palatable. The dissolution profiles of freeze-dried and heat-dried films were similar to Viagra® with f2 of 51.04 and 65.98, respectively.
    Matched MeSH terms: Freeze Drying
  20. Fulltext Preliminary Study of In Vitro Three-Dimensional Skin Model Using an Ovine Collagen Type I Sponge Seeded with Co-Culture Skin Cells: Submerged versus Air-Liquid Interface Conditions
    Fauzi MB, Rashidbenam Z, Bin Saim A, Binti Hj Idrus R
    Polymers (Basel), 2020 Nov 25;12(12).
    PMID: 33255581 DOI: 10.3390/polym12122784
    Three-dimensional (3D) in vitro skin models have been widely used for cosmeceutical and pharmaceutical applications aiming to reduce animal use in experiment. This study investigate capability of ovine tendon collagen type I (OTC-I) sponge suitable platform for a 3D in vitro skin model using co-cultured skin cells (CC) containing human epidermal keratinocytes (HEK) and human dermal fibroblasts (HDF) under submerged (SM) and air-liquid interface (ALI) conditions. Briefly, the extracted OTC-I was freeze-dried and crosslinked with genipin (OTC-I_GNP) and carbodiimide (OTC-I_EDC). The gross appearance, physico-chemical characteristics, biocompatibility and growth profile of seeded skin cells were assessed. The light brown and white appearance for the OTC-I_GNP scaffold and other groups were observed, respectively. The OTC-I_GNP scaffold demonstrated the highest swelling ratio (~1885%) and water uptake (94.96 ± 0.14%). The Fourier transformation infrared demonstrated amide A, B and I, II and III which represent collagen type I. The microstructure of all fabricated sponges presented a similar surface roughness with the presence of visible collagen fibers and a heterogenous porous structure. The OTC-I_EDC scaffold was more toxic and showed the lowest cell attachment and proliferation as compared to other groups. The micrographic evaluation revealed that CC potentially formed the epidermal- and dermal-like layers in both SM and ALI that prominently observed with OTC-I_GNP compared to others. In conclusion, these results suggest that OTC_GNP could be used as a 3D in vitro skin model under ALI microenvironment.
    Matched MeSH terms: Freeze Drying
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