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Ravindra Dhumal, Shamkant Shimpi and Anant Paradkar

Development of spray-dried co-precipitate of amorphous celecoxib containing storage and compression stabilizers

The purpose of this study was to obtain an amorphous system with minimum unit operations that will prevent recrystallization of amorphous drugs since preparation, during processing (compression) and further storage. Amorphous celecoxib, solid dispersion (SD) of celecoxib with polyvinyl pyrrollidone (PVP) and co-precipitate with PVP and carrageenan (CAR) in different ratios were prepared by the spray drying technique and compressed into tablets. Saturation solubility and dissolution studies were performed to differentiate performance after processing. Differential scanning calorimetry and X-ray powder difraction revealed the amorphous form of celecoxib, whereas infrared spectroscopy revealed hydrogen bonding between celecoxib and PVP. The dissolution profile of the solid dispersion and co-precipitate improved compared to celecoxib and amorphous celecoxib. Amorphous celecoxib was not stable on storage whereas the solid dispersion and co-precipitate powders were stable for 3 months. Tablets of the solid dispersion of celecoxib with PVP and physical mixture with PVP and carrageenan showed better resistance to recrystallization than amorphous celecoxib during compression but recrystallized on storage. However, tablets of co-precipitate with PVP and carageenan showed no evidence of crystallinity during stability studies with comparable dissolution profiles. This extraordinary stability of spray-dried co-precipitate tablets may be attributed to the cushioning action provided by the viscoelastic polymer CAR and hydrogen bonding interaction between celecoxib and PVP. The present study demonstrates the synergistic effect of combining two types of stabilizers, PVP and CAR, on the stability of amorphous drug during compression and storage as compared to their effect when used alone.

Open access

Zohreh Mohammadi, Farid Dorkoosh, Saman Hosseinkhani, Tina Amini, Amir Rahimi, Abdolhossein Najafabadi and Morteza Tehrani

, Stability analysis for long-term storage of naked DNA: impact on nonviral in vivo gene transfer, Anal. Biochem   318 (2003) 230-235; DOI: 10.1016/s0003-2697(03)00244-6. D. M. Prazeres, G. N. M. Ferreira, G. A. Monteiro, C. L. Cooney and J. M. S. Cabral, Large-scale production of pharmaceutical-grade plasmid DNA for gene therapy: problems and bottlenecks, Trends Biotechnol.   17 (1999) 169-174; DOI: 10.1016/s0167-7799(98)01291-8.

Open access

Aleš Franc, Slavomir Kurhajec, Sylvie Pavloková, Dana Sabadková and Jan Muselík

Abstract

The aim of this study was to find the optimal tablet composition with maximum content of dried fruits (Cornus mas L.). The effect of three different concentrations (12.5, 25 and 50 %) of two types of microcrystalline cellulose (Avicel® PH 101 and Avicel® PH 200) and three different compression pressures (20, 60 and 100 MPa) on the physical properties of tablet blends and tablets was studied. Tablets containing 50 % Avicel® PH 101 compressed under 100 MPa were found to have the best physical properties. This combination of composition and compression pressure resulted in stable tablets even after storage under accelerated stability conditions (6 months, 40 °C and 75 % RH).

Open access

Suphannee Thanyaphoo and Jasadee Kaewsrichan

Abstract

Silicon-substituted calcium phosphate (Si-CaP) was developed in our laboratory as a biomaterial for delivery in bone tissue engineering. It was fabricated as a 3D-construct of scaffolds using chitosan-trisodium polyphosphate (TPP) cross-linked networks. In this study, heparin was covalently bonded to the residual -NH2 groups of chitosan on the scaffold applying carbodiimide chemistry. Bonded heparin was not leached away from scaffold surfaces upon vigorous washing or extended storage. Recombinant human bone morphogenetic protein 2 (rhBMP-2) was bound to conjugated scaffolds by ionic interactions between the negatively charged SO42- clusters of heparin and positively charged amino acids of rhBMP-2. The resulting scaffolds were inspected for bone regenerative capacity by subcutaneous implanting in rats. Histological observation and mineralization assay were performed after 4 weeks of implantation. Results from both in vitro and in vivo experiments suggest the potential of the developed scaffolds for bone tissue engineering applications in the future.

Open access

Gleysson De Paula Terra, Marcus Vinícius De Farias, Marcello Garcia Trevisan and Jerusa Simone Garcia

Abstract

Pancreatin is a biotechnological product containing an enzyme complex, obtained from porcine pancreas, that is employed in treating pancreatic diseases. Experiments regarding the stability of the pharmaceutical formulation containing pancreatin were performed using standard binary mixtures with 6 excipients in a 1:1 ratio (m/m) and a commercial formulation. To accomplish these goals, samples were stored for 1, 3 and 6 months at 40 ± 1 °C and 75 ± 5 % relative humidity (RH) and 40 ± 1 °C and 0 % RH. Stress testing was also performed. All samples were analyzed to evaluate the α-amylase, lipase and protease activities through UV/Vis spectrophotometry. The results revealed that the excipient proprieties and the storage conditions affected enzyme stability. Humidity was a strong influencing factor in the reduction of α-amylase and protease activities. Stress testing indicated that pH 9.0 and UV light did not induce substantial alterations in enzyme activity.

Open access

Monika Musko and Malgorzata Sznitowska

Abstract

Available tablets or capsules for adults are often used to prepare extemporaneously formulated medicines appropriate for children. The most acceptable drug forms in pediatric population are oral liquids and pharmacists use commercial dispersing media to compound syrups from an active substance or from tablets available on the market. In many countries ready-to-use dispersing media are not available or refunded, but pharmacists can use other compounded media, providing their compatibility and stability are proven. The aim of this study was to formulate and evaluate the stability of syrups with candesartan cilexetil (1 mg mL-1) and valsartan (4 mg mL-1) extemporaneously prepared using commercial tablets (Diovan® and Atacand®). The following three different suspending media, which could be easily made in a pharmacy, were investigated: V1 - with xanthan gum (0.5 %), V2 - the USP/NF vehicle for oral solution and V3 - the medium based on a simple sucrose syrup. The stability of preparations was studied during 35 days of storage in a dark place at controlled temperature of 25 and 4 °C. During the study, microscopic observation was carried out and pH, viscosity, and concentration of candesartan cilexetil and valsartan were analyzed. Syrups with valsartan prepared with V2 and V3 media were stable for 3 or 4 weeks when stored at 25 °C, while syrups with candesartan were stable for as long as 35 days. For syrups prepared using V1 medium, the 14-day expiry date was not achieved because of microbial deterioration.

Open access

A. Polášková, J. Spilková, A. Matějíček and H. Studená

Abstract

The content of anthocyanins in fruits (Sambucus nigra. Vaccinium myrtillus. Aronia melanocarpa) and in some fruit (berry) products was determined by differential spectrophotometry, a method recommended by AOAC International (former Association of Official Analytical Chemists). The method takes advantage of the reversible pH-dependent transformation of the colour to the colourless form of anthocyanins. The procedure and evaluation were refined to allow measurements of incompletely specified anthocyanin mixtures. Parameters of the determination (buffer composition, pH, stabilisation of samples, reference standards) were optimised. Using the modified method, anthocyanins in various matrices (fruits, syrups, wines) were measured with the aim to explain possible losses of these active substances during processing and/or storage of fruit products. Real samples of commercial products recommended conventionally as a valuable source of antioxidants were analysed and in some of them, only low levels of anthocyanins were found. In a model arrangement, anthocyanins in the skin and the pulp of Sambucus nigra fruits were extracted separately. In all samples of various cultivars, anthocyanins were present predominantly in the skin (up to 90% of the total content). Considering this, among other factors, a suitable extraction technology might improve the quality of berry products substantially.

Open access

J. Valerio, S. Bernstorff and S.S. Funari

.-Regulat. Integ. Comp. Physiol. 1998, 276, R397-R406. [7] Seibel BA, Walsh PJ. Trimethylamine oxide accumulation in marine animals: relationship to acylglycerol storage. J. Exp. Biol. 2002, 198, 373-378. [8] Meersman F, Bowron D, Soper AK, Koch MHJ. An X-ray and neutron scattering study of the equilibrium between trimethylamine N-oxide and urea in aqueous solution. Phys. Chem. Chem. Phys.2011, 13(30), 13765-13771. [9] Tenchov B & Koynova R. Cubic phases in membrane lipids. Eur Biophys J (2012),41:841. [10] Ganguly

Open access

Stankovičová M., Bezáková Ž., Beňo P. and Húšťavová P.

1984;39: 213-225. [9] Lee, M.L., Stavchansky, S., Salomon, R.: Isothermal and non isothermal decomposition of thymopentin and its analogs in aqueous solution. Pharm Res 1998;15:1702-1707. [10] Rogers, A.R.: An accelerated storage test with programmed temperature rise. J Pharm Pharmacol 1963;15: 101T-105T. [11] Sedlarova, E., Bučiova, Ľ., Čižmarik J.: Analytical profile of 1-[2-(Pentyloxyphenylcarbamoyloxy)-(2-methoxymethyl)- ethyl]-perhydroazepinium chloride (BK 129). Čes slov Farm 1995;44:158-161. [12

Open access

S. Fialová, D. Tekeľová, K. Rendeková, J. Klinčok, M. Kolárik, K. Kurucová and D. Grančai

.). Phytother Res 2006;20(8):619‑33. [11] Murko D., Ramic S, Kekic M. Tannins of Salvia officinalis and their changes during storage. Planta Med. 1974;25:295-300. (in German). [12] Neugebauerová J, Kaffková K. Variability of essential oil content of Mentha L. taxa. Acta Univ Agric et Silvic Mendel Brun 2012;60:187-90. [13] Petersen M. Rosmarinic acid: new aspects. Phytochemistry Reviews. 2013;12:207-227. [14] Telci I., Shahbaz N. Determination of Agronomic and Essential Oil Properties of Peppermint (Mentha