scholarly journals Karakterisasi Karbamazepin Hasil Rekristalisasi Berbagai Pelarut Organik dengan Metode Slow Evaporation

2021 ◽  
Vol 8 (3) ◽  
pp. 227
Author(s):  
Indra Indra ◽  
Rendi Rahman ◽  
Rika Yulianti

Pendahuluan: Karbamazepin termasuk ke dalam golongan Biopharmaceutical Classification System (BCS) kelas II yang artinya bahwa karbamazepin memiliki permeabilitas membran tinggi dan kelarutan rendah. Rekristalisasi merupakan salah satu cara untuk memodifikasi kristal dalam upaya mengubah sifat fisikokimia dan laju disolusi obat. Tujuan: Penelitian ini bertujuan untuk mengevaluasi sifat fisikokimia karbamazepin melalui rekristalisasi berbagai pelarut. Metode: Pada penelitian ini dilakukan rekristalisasi dengan cara penguapan pelarut menggunakan pelarut etanol, tetrahidrofuran (THF), dan kloroform. Padatan kristal hasil rekristalisasi dikarakterisasi dengan menggunakan spektrofotometri FTIR, difraksi sinar-X (PXRD), dan analisis differential scanning calorimetry (DSC). Selanjutnya dilakukan evaluasi mikromeritik dan uji disolusi. Hasil: Berdasarkan hasil karakterisasi dengan FTIR dan PXRD menunjukan tidak terjadi perubahan struktur kimia dari karbamazepin, tetapi menyebabkan perubahan internal struktur dan perubahan bentuk (polimorfisme) kristal karbamazepin. Hasil evaluasi mikromeritik menunjukkan adanya perubahan sifat fungsional pada padatan kristal hasil rekristalisasi dibandingkan dengan karbamazepin murni, diketahui padatan kristal hasil rekristalisasi etanol menunjukkan sifat mikromeritik yang lebih baik dibandingkan bentuk murni. Uji disolusi menunjukkan bahwa terjadi peningkatan laju disolusi pada padatan kristal hasil rekristalisasi berbagai pelarut dibandingkan dengan karbamazepin murni. Pada padatan kristal hasil rekristalisasi THF memiliki laju disolusi paling tinggi dari pelarut yang lain, yaitu pada menit ke-60 jumlah terdisolusi sebesar 65,09%. Kesimpulan: Proses rekristalisasi karbamazepin dengan pelarut etanol, tetrahidrofuran dan kloroform menghasilkan polimorf baru sehingga sifat fisikokimia padatan hasil rekristalisasi berbeda dibandingkan karbamazepin murni. Berdasarkan hasil uji disolusi in vitro dapat diketahui bahwa karbamazepin hasil rekristalisasi dengan pelarut tetrahidrofuran memiliki laju disolusi yang paling tinggi.

2017 ◽  
Vol 73 (4) ◽  
pp. 305-313 ◽  
Author(s):  
Yun-Deng Wu ◽  
Xiao-Lei Zhang ◽  
Xiao-Hong Liu ◽  
Jian Xu ◽  
Mei Zhang ◽  
...  

Apremilast (AP) {systematic name: (S)-2-[1-(3-ethoxy-4-methoxyphenyl)-2-(methylsulfonyl)ethyl]-4-acetamidoisoindoline-1,3-dione} is an inhibitor of phosphodieasterase-4 (PDE4) and is indicated for the treatment of adult patients with active psoriatic arthritis. The ability of AP to form solvates has been investigated and three solvatomorphs of AP, namely, the AP ethyl acetate hemisolvate, C22H24N2O7S·0.5C4H8O2, the AP toluene hemisolvate, C22H24N2O7S·0.5C7H8, and the AP dichloromethane monosolvate, C22H24N2O7S·CH2Cl2, were obtained. The three AP solvatomorphs were characterized by X-ray powder diffraction, thermogravimetric analysis and differential scanning calorimetry. Single-crystal X-ray diffraction was used to analyze the structures, crystal symmetry, packing modes, stoichiometry and hydrogen-bonding interactions of the solvatomorphs. In addition, dissolution analyses were performed to study the dissolution rates of different AP solvatomorph tablets in vitro and to make comparisons with commercial apremilast tablets (produced by Celgene); all three solvatomorphs showed similar dissolution rates and similar values of the similarity factor f2 in a comparison of their dissolution profiles.


2019 ◽  
Vol 680 ◽  
pp. 178358 ◽  
Author(s):  
Agnieszka Kiełboń ◽  
Anna Michnik ◽  
Kinga Polaczek Grelik ◽  
Klaudia Duch ◽  
Ewa Sadowska-Krępa

Pharmaceutics ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 473 ◽  
Author(s):  
Anna Czerniecka-Kubicka ◽  
Piotr Tutka ◽  
Marek Pyda ◽  
Małgorzata Walczak ◽  
Łukasz Uram ◽  
...  

Third-generation poly(amidoamine) dendrimer (PAMAM) was modified by stepwise primary amine group amidation with d-glucoheptono-1,4-lactone. The physicochemical properties of the conjugates—size, ζ potential in lysosomal pH 5 and in neutral aqueous solutions, as well as intramolecular dynamics by differential scanning calorimetry—were determined. Internalization and toxicity of the conjugates against normal human fibroblasts BJ were monitored in vitro in order to select an appropriate carrier for a drug delivery system. It was found that initial glucoheptoamidation (up to 1/3 of amine groups of neat dendrimers available) resulted in increase of conjugate size and ζ potential. Native or low substituted dendrimer conjugates accumulated efficiently in fibroblast cells at nontoxic 1 µM concentration. Further substitution of dendrimer caused consistent decrease of size and ζ potential, cell accumulation, and toxicity. All dendrimers are amorphous at 36.6 °C as determined by differential scanning calorimetry (DSC). The optimized dendrimer, half-filled with glucoheptoamide substituents, was applied as carrier bearing two covalently attached cytisine molecules: a rigid and hydrophobic alkaloid. The conjugate with 2 cytisine and 16 glucoheptoamide substituents showed fast accumulation and no toxicity up to 200 µM concentration. The half-glucoheptoamidated PAMAM dendrimer was selected as a promising anticancer drug carrier for further applications.


2011 ◽  
Vol 2011 ◽  
pp. 1-9 ◽  
Author(s):  
Carlos Suárez ◽  
Teresa Vilar ◽  
Pablo Sevilla ◽  
Javier Gil

Objectives. To investigate the in vitro electrochemical corrosive behavior of archwires used in lingual orthodontics and the effects on the phase transition temperatures.Materials and Methods. Six different types of archwires of stainless steel, titanium-molybdenum, nickel-titanium and nickel-titanium-copper were used. Corrosion tests were performed following ISO-standard 10993-15:2000. Differential scanning calorimetry and scanning electron microscopy were used.Results. The stainless steel archwires showed anEpitaround −600 mV, and those of titanium alloys showedEpitvalues around 1000 mV. Differential scanning calorimetry detected a rhombohedral phase in nickel-titanium archwires, while it was not detected in nickel-titanium-copper wires. A difference of 2°C to 3.5°C from the manufacturer's claim was found in the as-received and polarized samples, respectively.Conclusions. The 0.016 stainless steel archwires were found to be the less resistant to corrosion. A rhombohedral phase was detected on the nickel-titanium archwires. No major differences were observed among groups concerning phase transformation temperatures.


2020 ◽  
Vol 12 (4) ◽  
pp. 22-29
Author(s):  
KanchanV Zade ◽  
Alok Pal Jain

Phytosome is a complex between natural active ingredient and a phospholipid. Further, phytosomes been applied to many popular herbal extracts or active molecules for augmenting oral dissolution. Therefore, in present investigation, orally administered Baicalein, atype of flavanoids, is poorly absorbed, and shows suboptimal dissolution. The phytosomes encapsulating baicalein (1:1 Mm) were prepared by reverse phase evaporation method followed by lyophilization. Transmission electron microscopy (TEM) analysis revealed that phytosomes were almost spherical in shape with particle size below 100 nm. The Powder ex-ray diffraction (PXRD) and differential scanning calorimetry (DSC) demonstrated that Baicalein loaded phytosomes were amorphous in nature. Amorphization of therapeutic moiety leads to improvement in dissolution. In conclusion, epigallocatechin loaded phytosomes exhibited promising results and warrant further in vitro andin vivo investigations under a set of stringent parameters for transforming in to a clinically viable products.


Author(s):  
S. Princely ◽  
Saleem Basha N ◽  
Saleem Basha N ◽  
Nandhakumar S ◽  
Dhanaraju Md

ABSTRACTObjective: Lamivudine (LVD) is a nucleoside reverse transcriptase inhibitor originally developed as an antiretroviral drug and primarily used in thetreatment of most common chronic disease of the planet, acquired immune deficiency syndrome and hepatitis B. The main objective of the study is todevelop controlled drug delivery system to increase the efficacy of antiretroviral drug, LVD against human immunodeficiency virus infections.Methods: The microencapsulation of LVD in gelatin microspheres was carried out by cross-linking process with glutaraldehyde saturated tolueneusing ionic-gelation method. The prepared microspheres were evaluated for particle size analysis, % yield value, % drug content, drug entrapmentefficiency, scanning electron microscopy for surface morphology, swelling index, accelerated stability studies, Fourier transform infrared radiationspectroscopy (FT-IR) and differential scanning calorimetry (DSC) for polymer drug compatibility, in vitro dissolution efficiency and release kineticstudies.Results: The obtained microspheres showed very smooth surface and exhibited regular spherical geometry due to higher crosslinking density. FT-IRand DSC revealed the absence of drug polymer interactions. The percentage yield, entrapment efficiency and drug content for F6 LVD microsphereswas found to be 79.31%, 65.55% and 96.25% respectively. The particle size was ranged from 34.61% to 51.45 µm sizes and in vitro release profileshowed that cross-linking density of gelatin microspheres effectively controlled the release of LVD.Conclusion: The findings of our investigation demonstrated that F6 of gelatin-LVD microspheres had good controlled release profile with maximumentrapment efficiency and prolonged drug release for 24 hrs or longer and this formulation would be capable of overcoming the drawbacks andlimitations of LVD conventional dosage forms.Keywords: Lamivudine, Microspheres, Controlled release, Gelatin, Fourier transform infrared, Differential scanning calorimetry, In vitro releasekinetics.


2018 ◽  
Vol 10 (4) ◽  
pp. 133 ◽  
Author(s):  
Shweta Gedam ◽  
Pritee Jadhav ◽  
Swati Talele ◽  
Anil Jadhav

Objective: The present investigation was undertaken to develop and evaluate a gastroretentive mucoadhesive microspheres of anti-osteoporosis drug risedronate sodium to enhance the residence time and drug release by studying the effect of the crosslinking agent to obtain the best formulation with reduced particle size and good in vitro mucoadhesion strength.Methods: Selected drug risedronate sodium is a potent pyridinyl bisphosphonate used for the treatment of osteoporosis, and other bone disorders. Microspheres using sodium alginate as a polymer and calcium chloride solution as a cross-linker were prepared successfully by the emulsification crosslinking method. The 23 factorial design was used to study the effects of various variables like a drug: polymer ratio, crosslinking agent concentration and crosslinking time on the particle size and in vitro mucoadhesion strength. All these formulations were evaluated for entrapment efficiency, percentage yield and cumulative drug release. F1 batch was selected as best formulation and evaluated for scanning electron microscopy, fourier transforms infrared spectroscopy, differential scanning calorimetry, stability study.Results: Design batches were evaluated for percent yield (61.29-89.33%), % entrapment efficiency (42.25±0.620-62.58±0.330), mucoadhesion strength (68.15±0.37-82.24±0.72%) and drug release at 12 h (67-84%). Among the microspheres formulation, an F1 batch of (0.5:1) drug: polymer concentration and at 4% concentration of calcium chloride as a crosslinker was considered best formulation with reduced particle size 32.85±0.774μm, % intro mucoadhesion. 82.24±0.72. In vitro mucoadhesion strength was increased with the increasing crosslinking time from 5 min to 10 min. The fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) study showed no interaction between drug and polymer. X-ray diffraction (XRD) spectrum of microspheres indicates that drug particles are dispersed at the molecular level in the polymer matrices so no indication of the crystalline nature of the drug nature. Scanning electron microscopic (SEM) study showed that microspheres were spherical in shape with a smooth surface. F1 batch shows percentage cumulative drug release 84.07%. In vitro dissolution studies indicates that percent cumulative drug release from microspheres follows zero order kinetics plot which indicates controlled-release drug-delivery for 12 h which leads to control of plasma concentration.Conclusion: The results show that the formulation that contains (0.5:1) drug: polymer ratio, calcium chloride in 4% concentration and crosslinking time 10 min is the best one and can be utilized to formulate risedronate sodium mucoadhesive microspheres to enhance gastric residence time, improved patient compliance and reduction in the frequency of drug administration.


Author(s):  
HARITA R. DESAI ◽  
ARCHANA B. RAJADHYAX ◽  
PURNIMA D. AMIN

Objective: The objective of the current study was to explore top down methods of size reduction like high speed homogenisation and media milling in synergism with spray drying in amorphization and solubility enhancement of BCS Class II antilipidemic drug Simvastatin USP. Methods: Spray-dried micronized simvastatin USP was formulated by homogenisation and media milling of drug suspension in optimized stabilizer solution. Stabilizer combination, duration of homogenisation and ball milling and drug: stabilizer ratio was optimized. The obtained dispersion was transformed into solid powder using spray drying. The obtained Spray-dried micronized Simvastatin USP was evaluated for visual morphology, Infrared spectroscopy, Differential scanning calorimetry, in vitro drug release studies, X-Ray diffractometry, Scanning electron microscopy, contact angle measurement, solubility studies, dispersibility studies and intrinsic dissolution rate testing. Results: Spray-dried micronized simvastatin USP was found to show amorphization of crystalline Simvastatin USP as confirmed by the absence of drug peak in Differential scanning calorimetry and lowered signal intensity in X-Ray diffraction studies. Spray-dried micronized Simvastatin USP was found to show enhanced drug hydrophilicity and solubility as confirmed by lowering in contact angle and increase in solubility and ease of dispersibility observations. In vitro dissolution testing and intrinsic dissolution rate testing were found to show an increase in drug release from 11% to 79% and 4 mg min-1 cm-2 to 17 mg min-1 cm-2 for drug and Spray-dried micronized Simvastatin USP respectively. Conclusion: Media milling in synergism with spray-drying was found to be a prospective solubility enhancement technique for poorly-soluble Simvastatin USP.


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