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Circular RNAs (circRNAs) are highly stable forms of endogenous non-coding RNA molecules with diverse biological functions. Some of them have been demonstrated to play crucial roles in the initiation or development of cancers through regulation of gene expression. However, the profiles and the roles of circRNAs in tumorigenesis of cervical cancer remain largely unknown. In the current study, we investigated the expression profiles of circRNAs and their potential oncogenic mechanisms in cervical cancer. The expression patterns, obtained using a microarray assay, revealed a total of 192 differentially expressed circRNAs, of which 106 were upregulated and 86 were downregulated, in cervical cancer samples compared with normal cervical samples. The differential expression of circRNAs was validated using quantitative real-time polymerase chain reaction. Two circRNAs (circTPCN and circFAM185A) were confirmed to be significantly upregulated in cervical cancer samples, indicating that they represent potential biomarkers of cervical cancer. The role and the potential molecular mechanism of circTPCN in cervical cancer tumorigenesis were further investigated. Knockdown of circTPCN significantly suppressed proliferation, migration, and invasion and increased apoptosis of cervical cancer cells in vitro. Molecular analysis revealed that circTPCN acted as a sponge of miR-634 to enhance mTOR expression. Thus, the circTPCN/miR-634/mTOR regulatory pathway might be involved in cervical cancer tumorigenesis, and circTPCN is a potential therapeutic target in cervical cancer.
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MicroARNs , Neoplasias del Cuello Uterino , Carcinogénesis/genética , Proliferación Celular/genética , Femenino , Humanos , MicroARNs/genética , MicroARNs/metabolismo , ARN Circular , Serina-Treonina Quinasas TOR/genética , Neoplasias del Cuello Uterino/genéticaRESUMEN
The purpose of the present study was to optimize the formulations of the thermoresponsive ophthalmic in situ gels of a poorly water-soluble drug fluconazole (FLU) and evaluate the in vitro and in vivo properties of the formulations. The thermoresponsive ophthalmic FLU in situ gels were prepared by mixing FLU, Poloxamer407, Tween80, benzalkonium chloride and carbopol934 in borate buffer solution. The in vivo eye irritation tests and ophthalmic absorption were carried out in rabbits. The formulation compositions influenced the physicochemical properties of FLU in situ gels. The amount of poloxamer407 in the formulation was the main factor that affected the sol-gel transition temperature of the products. Tween80 not only improved the solubility of the FLU but also affected the products' sol-gel transition temperature. In this study, sol-gel transition temperature was not affected by carbopol934. However, carbopol934 affected pH value, transparency and gelling capacity of the products. The product of the optimized formulation was a pseudoplastic fluid and its sol-gel transition temperature was 30.6 ± 1.2 °C. The autoclaving test showed that the sol-gel transition temperature, the flow ability and the flow behavior of the test samples did not change obviously after autoclaving sterilization at 121 °C and 15 psi for 20 min, thus the autoclaving was an acceptable sterilization method for this preparation. The thermoresponsive ophthalmic FLU in situ gels' in vivo ophthalmic absorption was superior to the conventional FLU eye drop. In conclusion, the thermoresponsive ophthalmic FLU in situ gel is a better alternative than the FLU eye drop.
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Antifúngicos/administración & dosificación , Excipientes/química , Fluconazol/administración & dosificación , Acrilatos/química , Administración Oftálmica , Animales , Antifúngicos/química , Antifúngicos/farmacocinética , Compuestos de Benzalconio/química , Química Farmacéutica , Femenino , Fluconazol/química , Fluconazol/farmacocinética , Geles , Concentración de Iones de Hidrógeno , Masculino , Soluciones Oftálmicas , Poloxámero/química , Polisorbatos/química , Conejos , Solubilidad , Esterilización , Temperatura , Temperatura de TransiciónRESUMEN
BACKGROUND: In the system of the iontophoresis, the external electric field made the ions in the system moving directly, then, the current was generated. Because the current was contributed by all ions in the system, and the small ions with large amount often had higher conductibility than the drug ions, the fraction of the total current contributed by the drug ions was often low. It was the main reason for the generally low efficiency of the transdermal iontophoretic drug delivery. OBJECTIVES: The objective of this study was to find a novel method to increase the fraction of the total current contributed by the drug ions so as to enhance the drug's iontophoretic delivery. METHOD: Iontophoretic transport of nefopam hydrochloride solution and iontophoretic transport of nefopam assisted by ion-exchange materials, including ion-exchange resin, ion-exchange membrane and ion-exchange fiber, across the rat skin were investigated. RESULTS: Both in vitro and in vivo iontophoretic transport experiments showed that the efficiency of the nefopam-fiber iontophoretic system for nefopam permeating across rat skin was the highest among four iontophoretic systems (nefopam solution, nefopam-resin, nefopam-membrane and nefopam-fiber). CONCLUSION: The results of this study suggested that there was an enhancement of nefopam across rat skin by ion-exchange fibers in ion-exchange fibers assisted iontophoresis. The present study has demonstrated the potential of a new approach of using ion-exchange fibers to improve the efficiency of the transdermal iontophoresis for cationizable drugs.
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Analgésicos no Narcóticos/farmacocinética , Iontoforesis/métodos , Nefopam/farmacocinética , Absorción Cutánea , Administración Cutánea , Analgésicos no Narcóticos/administración & dosificación , Animales , Transporte Biológico , Sistemas de Liberación de Medicamentos , Intercambio Iónico , Resinas de Intercambio Iónico/química , Masculino , Nefopam/administración & dosificación , Permeabilidad , Ratas , Ratas Wistar , Piel/metabolismoRESUMEN
Water insoluble faintly alkaline drugs often have potential absorption problem in gastrointestinal tract in oral administration for patients with gastric anacidity. The purpose of the present study is to develop a novel method to improve the absorption of the water insoluble faintly alkaline drug in peroral administration. This method is based on ion exchange of ion-exchange fibers. Water-insoluble faintly alkaline drug ketoconazole was used as a model drug. Ketoconazole and the active groups of the ion-exchange fibers combined into ion pairs based on the acid-base reaction. This drug carrier did not release drugs in deionized water, but in water solution containing other ions it would release the drugs into the solution by ion exchange. Confirmed by the X-ray diffraction and the differential scanning calorimetry (DSC), the ketoconazole combined onto the ion-exchange fibers was in a highly molecular level dispersed state. The improved dissolution of ketoconazole ion-exchange fiber complexes is likely to originate from this ketoconazole's highly dispersed state. Furthermore, due to this ketoconazole's highly dispersed state, ketoconazole ion-exchange fiber complexes significantly decreased the individual difference of absorption in oral administration of ketoconazole caused by the fluctuation of the acid degree in the gastric fluid.
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Tracto Gastrointestinal/metabolismo , Cetoconazol/química , Cetoconazol/farmacocinética , Absorción , Administración Oral , Animales , Disponibilidad Biológica , Portadores de Fármacos/química , Intercambio Iónico , Cetoconazol/administración & dosificación , Masculino , Ratas , Ratas Sprague-Dawley , SolubilidadRESUMEN
Dihydroorotate dehydrogenase (DHODH) is a flavin-dependent metabolic enzyme that oxidizes dihydroorotate acid to orotic acid in the de novo synthesis pathway of pyrimidine metabolism. DHODH is located in mitochondria, closely related to cellular oxidative phosphorylation, and an important suppressor of the ferroptosis pathway. This study investigates the influence of DHODH on the progression of malignant tumors, including its important role in the de novo synthesis of pyrimidine, oxidative phosphorylation, and ferroptosis. The objective is to present evidence that DHODH is a potential target for the clinical treatment of tumors.
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OBJECTIVE To evaluate the efficacy of the functional dressing of Polygonum capitatum nanofibers (P-PVP-PCL). METHODS P-PVP-PCL were prepared by electrospinning technology, and the microstructure of P-PVP-PCL was observed. The antibacterial activity and antioxidant activity of P-PVP-PCL and its effects on the survival rate, adhesion and migration rate of mouse fibroblast L929 cells were investigated. The effects of medical gauze dressing, blank nanofiber dressing (PVP-PCL) and P- PVP-PCL on the healing rate of the wound were investigated by establishing the back skin wound model of rats. The pathological changes of the wound tissue and collagen fiber deposition were observed, as well as the number of platelet endothelial cell adhesion molecule-1 (CD31) positive blood vessels and the expression of transforming growth factor-β (TGF-β) protein in wound tissue. RESULTS P-PVP-PCL had a smooth surface and a double-layer structure at the cross-section. The inhibition rates of P-PVP-PCL against Staphylococcus aureus and Escherichia coli were (98.88±0.66)% and (94.75±1.41)% , respectively. The antioxidant activity of P-PVP-PCL was (83.69±1.56)%, and the cell activity of the P-PVP-PCL group was significantly higher than those of the control group and PVP-PCL group (P<0.05). Compared with medical gauze dressings, P-PVP-PCL was more conducive to L929 cell adhesion; at 48 hours, the cell scratches in this group had basically healed. Compared with the medical gauze dressing group, the wound healing rates of the PVP-PCL group and the P-PVP-PCL group were significantly increased (P<0.05). On the 14th day of intervention, the wounds in the P-PVP-PCL group had basically healed, there was no dermal necrosis in the wound tissue, and the collagen fibers were arranged relatively neatly and the density was relatively uniform. The number of CD31 positive blood vessels and the expression of TGF-β protein showed a downward trend compared with the 7th day of intervention, and the number of CD31 positive blood vessels was significantly lower than those of the medical gauze dressing group and PVP-PCL group (P<0.05), but the protein expression of TGF- β was significantly higher than those of the medical gauze dressing group and the PVP-PCL group (P<0.05). CONCLUSIONS P-PVP-PCL has good antibacterial and antioxidant activity in E-mail:444096585@qq.com vitro, and can promote the proliferation, adhesion and migration of L929 cells. It can promote wound healing of rats in vivo.
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This article reported the clinical features of a rare patient with anti-metabotropic glutamate receptor 5 (mGluR5) encephalitis with mental disorders as the initial symptom, so as to provide references for clinical diagnosis and treatment. The patient was a 38-year-old male, developed pharyngeal pain as prodromal symptoms, and the main clinical manifestations included rapidly progressive memory loss, anxiety and depression, and psychomotor excitement symptoms including irritability and impulsive behaviors. The disease had a progressive deterioration. In the most severe state, the patient became unconscious in a shallow coma, with further cognitive decline, hallucinations and delusions, and lack of self-awareness. Both cerebrospinal fluid and serum anti-mGluR5 antibody were strongly positive (1∶100). After two sessions of hormone shock therapy, the patient showed significantly improvement in consciousness, cognitive, emotional and psychiatric dimensions.
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@#AIM: The changes of optic disc and macular blood flow in POAG patients with different symptom types of traditional chinese medicine(TCM)were detected by OCTA, and the correlation between them and optic nerve damage was analyzed.<p>METHODS: Totally 103 eyes of 103 POAG patients were classified according to the different symptom types of TCM. The vascular density of optic disc, the vascular density of macular area, the thickness of peripapillary retinal nerve fiber layer(pRNFL), and the thickness of ganglia cell complex(GCC)were collected by OCTA, and then the differences among them were analyzed. The correlation between the blood flow parameters and visual field of mean deviation(MD)was also analyzed. <p>RESULTS: There were significant differences in best corrected visual acuity(BCVA), intraocular pressure(IOP)and course of disease among the three groups of POAG patients(<i>F</i>=29.671, 13.05, 108.60; all <i>P</i><0.01). The differences in macular GCC thickness, pRNFL thickness, optic disc vascular density and macular vascular density in different regions among the three groups were significant(<i>P</i><0.01). Linear positive correlation were found between optic disc vascular density, macular vascular density and visual field MD(<i>r</i>=0.591, 0.402, all <i>P</i><0.001).<p>CONCLUSION: OCTA can be used as an evaluation index for POAG patients with different symptom types, and it can provide a strong objective theoretical basis for the treatment of POAG.
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Hydrochloric thiothixene (HT) is an antipsychotic drug used in the treatment of various psychoses including schizophrenia, mania, polar disorder, and in behavior disturbances. However, because the psychotics often could not control their behaviors, the independent administration of antipsychotic drug based on medical order was difficult. The omissions of the administration often brought an unsatisfactory therapeutic efficacy. A novel injectable long-term control-released in situ gel of HT for the treatment of schizophrenia was developed based on biodegradable material polylactic acid (PLA). The optimum formulation of the injectable PLA-based HT in situ gel containing 15% (w/w) HT and 45% (w/w) PLA with benzyl benzoate was used as a gelling solvent. The results of the in vitro and in vivo studies showed that this in situ gel had a long-term period of drug release for several weeks and a good histocompatibility without any remarkable inflammatory reactions.
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Antipsicóticos/química , Portadores de Fármacos , Ácido Láctico/química , Polímeros/química , Esquizofrenia/tratamiento farmacológico , Tiotixeno/química , Animales , Antipsicóticos/administración & dosificación , Antipsicóticos/sangre , Antipsicóticos/farmacocinética , Benzoatos/química , Química Farmacéutica , Preparaciones de Acción Retardada , Geles , Humanos , Inyecciones Intramusculares , Masculino , Poliésteres , Ratas Wistar , Solubilidad , Tecnología Farmacéutica/métodos , Tiotixeno/administración & dosificación , Tiotixeno/sangre , Tiotixeno/farmacocinéticaRESUMEN
OBJECTIVE: To design and optimize the formulation and technology of Theophylline hydrophilic gel matrix sustained-release tablets (self-made sustained-release tablets for short) based on the concept of “Quality by Design” (QbD). METHODS: Diluent type, tablet diameter, the property of adhesive (ratio of different adhesive types), the amount of adhesive were regarded as critical process parameters (CPPs). Similarity factor of dissolution curves of self-made Theophylline sustained-release tablets and reference preparation and its accumulative release rate at different time points were regarded as critical quality attributes (CQAs). L18(34) orthogonal tablet was adopted for design and trial, and secondary polynomial regression model was established. By using Modde 12.0 software, the design space and its acceptable range (PAR) were calculated through the optimal model. The optimal formulation and technology of Theophylline sustained-release tablets was determined, and validation test and Monte Carlo simulation verification were conducted. RESULTS: The optimal model with good coincidence, accuracy, validity and reproducibility was obtained, which could better fit the relationship between CQAs and CPPs. The design space and PAR value were obtained by further calculation (The optimum value of diluent was lactose; tablet diameter was 9.07-9.33 mm, and the optimal value was 9.20 mm; ratio of HPMC K4M to HPMC was 0.50-0.83, and the optimal value was 0.80; total amount of HPMC was 0.036 0-0.041 3 g per tablet, and the optimal value was 0.038 g per tablet). The optimal formulation and technology included that ratio of theophylline, HPMC K4M and HPMC K100M were 50%, 15.48% and 3.87%, respectively; the rest was filled with lactose and the diameter of the tablet was 9.20 mm. The results of validation confirmed that self-made Theophylline sustained-release tablets had similar in vitro release behavior compared with reference preparation. CONCLUSIONS: Based on the concept of QbD, the formulation and technology of Theophylline sustained-release tablets can meet the requirements of design, and the CPPs can be adjusted within the PAR range to meet the requirements of CQAs. This shows that the QbD concept is scientific and effective in the design and optimization of the formulation and technology of sustained and controlled release preparations.
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Objective To investigate the diagnostic significance of optical coherence tomography angiography (OCTA) in the detection of primary glaucoma.Methods Totally 70 patients (116 eyes) of primary glaucoma were selected as the experimental group and 20 normal subjects (36 eyes) as the control group.The changes in macular vessel density,macular retinal ganglion cell (RGC) thickness,macular thickness,and optic disc retinal pigment epithelium (RPE) opening distance were measured by OCTA,and the correlation between the parameters and the mean deviation (MD) of visual field.Results When compared with the control group,the upper macular thickness,inferior macular thickness,macular RGC thickness and macular vessel density were reduced in the experimental group (all P < 0.05).There was no significant difference in optic disc RPE opening distance between the control group and the experimental group (F =2.646,P =0.051 3).Linear positive correlations were found between macular thickness,macular RGC thickness,macular vessel density and MD (all r > 0.5,P <0.01).The area under the curve of the diagnostic ROC curve of the macular vessel density,macular RGC thickness and mactlar thickness for glaucoma were all greater than 0.7.Conelusion There are linear positive correlations between macular thickness,macular RGC thickness,macular vessel density and MD.The parameters have a high diagnostic ability for the primary glaucoma.OCTA is a valuable technique for detecting glaucoma.
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BACKGROUND: The organic solvent solution immersion method was often used to achieve the loading of the drugs into mesoporous silica, but the drugs that have loaded into the pores of the mesoporous silica would inevitable migrate from the inside to the external surface or near the outside surface during the process of drying. Hence, it often leads to the pores of mesoporous materials not be fully utilized, and results in a low drug loading efficiency and a fast releasing rate. OBJECTIVE: The purpose of this study was to develop a novel drug loading strategy to avoid soluble component migration during the process of drying, then, to prepare poorly water-soluble drug mesoporous silica microparticles with higher drug loading efficiency and longer sustained-release time. METHOD: Ibuprofen was used as model drug. The microparticles were prepared by a novel method based on mesoporous silica and supercritical fluid (SCF) technique. The drug-loaded mesoporous silica microparticles prepared by SCF technique were analyzed by thermogravimetric analysis (TGA), N2 adsorption/desorption, scanning electron microscopy (SEM), powder X-ray diffraction (XRD) and differential scanning calorimetry (DSC). In vitro releasing study was used to evaluate the sustained-release effect of the drug-loaded microparticles. RESULTS: By virtue of the high diffusibility and the high dissolving capacity of the supercritical carbon dioxide (SCF-CO2), the poorly water-soluble drugs, ibuprofen, entered the pores of the mesoporous silica. The amount and the depth of ibuprofen entered the pores of the mesoporous silica by SCF technique were both larger than those by the solution immersion method. It was found that ibuprofen loaded into the mesoporous silica by SCF technique was amorphous and the largest amount of the ibuprofen loaded into the mesoporous silica by SCF technique could reach 386 mg/g (w/w, ibuprofen/SiO2), it was more than that by the solution immersion method. In vitro releasing study showed that the sustained-release effect of ibuprofen in the samples prepared by SCF technique was 50% in 15 min and 90% in 60 min. It was longer than that prepared by the solution immersion method. CONCLUSION: Present study showed that sustained-release poorly water-soluble drug mesoporous silica microparticle based on SCF technique has twofold advantages. One is the larger drug loading amount in internal pores of the mesoporous silica, the other is the longer drug releasing time.
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Cromatografía con Fluido Supercrítico , Portadores de Fármacos , Ibuprofeno/química , Dióxido de Silicio/química , Solventes/química , Tecnología Farmacéutica/métodos , Agua/química , Adsorción , Rastreo Diferencial de Calorimetría , Química Farmacéutica , Cristalografía por Rayos X , Preparaciones de Acción Retardada , Difusión , Cinética , Microscopía Electrónica de Rastreo , Tamaño de la Partícula , Porosidad , Difracción de Polvo , Solubilidad , TermogravimetríaRESUMEN
This article described the current status of problems in quality and safety in TCM industry. It also emphatically discussed the quality and safety control in TCM production process. In addition, this article used the HACCP (Hazard Analysis and Critical Control Points) system to conduct a hazard analysis on TCM production process and determined the critical control points, and carried out the corresponding control measures, with a purpose to realize effective regulation and control of hazard factors and ensure TCM quality and safety.
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AIM:To evaluate the morphological and functional changes of retinas induced by treatment of tunicamycin with optical coherence tomography (OCT) in rats.METHODS:Totally 60 SD rats were randomly divided into 3 groups (20 in each group), 0.5mg/kg (in low dose group), 1.5mg/kg (in high dose group) tunicamycin were injected into vitreous cavity and saline (9g/L NaCl) were injected in the same dose as a control group.Changes of retinas were observed by OCT on the 1,7 and 14d after treatment of tunicamycin.Then the rats were sacrificed, retinas were taken out and embedded by the paraffin, tissue sections and the HE staining were performed.RESULTS:OCT results suggested that tunicamycin played damage effects on retinal morphology and structure which appeared a time-and dose-dependent.Fundus photography results suggested that 2wk after tunicamycin treatments, with the gradually changing of tunicamycin concentration, peripheral retinal and macular region became pale color gradually, edema occurred in optic disk, retinal vessels appeared thinner in the high dose group, optic nerve came out atrophy.Fluorescein angiography confirmed that tunicamycin injection in vitreous cavity 2wk later, retinal vessels injury occurred, resulted in leaking of intravascular contrast agent from peripheral to the central part of the retinas.Electrophysiological data showed that retinal electrogram occurred disorder induced by tunicamycin, such as the amplitude of a wave, b wave decreased gradually, even closed to zero, which was very different from control significantly (P<0.05).HE staining of paraffin sections showed that retina injuries induced by tunicamycin were in dose-time dependent, which was consistent with the results of OCT.CONCLUSION: Clinical retinal diseases could be simulated by retinal damage animal model induced by tunicamycin treatment.OCT detection offered real-time images of the retinal cross-section, which provided a helpful non-invasive method for detecting and evaluating the retinal damages.
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The main reason for generally low efficiency of the transdermal iontophoretic drug delivery is that the fraction of the total current contributed by the drug ions is very small. The objective of this study was to find a method to increase the fraction of the total current contributed by the drug ions so as to enhance the drug's iontophoretic delivery. Iontophoretic transport of diclofenac solution and diclofenac assisted by ion exchange materials, including ion-exchange resin, ion-exchange membrane and ion-exchange fiber, across the rat skin were investigated. Both in vitro and in vivo iontophoretic transport experiments showed the amount of diclofenac permeated across rat skin from the diclofenac-fibers was highest among those from the diclofenac simple solutions and ion exchange materials complexes. The results of this study suggested that there is an enhancement of drug across rat skin by ion-exchange fibers in ion-exchange fibers assisted iontophoresis. The present study has demonstrated the potential of a new approach using ion-exchange fibers to enhance transdermal iontophoretic transport of an ionizable drug.
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Sistemas de Liberación de Medicamentos/métodos , Resinas de Intercambio Iónico/química , Iontoforesis/métodos , Piel/metabolismo , Administración Cutánea , Animales , Transporte Biológico , Diclofenaco/química , Intercambio Iónico , Iones/química , Masculino , Permeabilidad , Ratas , Ratas Wistar , Absorción CutáneaRESUMEN
Game relationship of mutual restriction and mutual connection exist among various segments of Chinese medicine decoction pieces supply chain. Any problems in any segments will affect quality and safety of the whole supply chain, and ultimately affect the safety of consumers. Based on the theory of supply chain, this article established a linear supply chain and static game model, including planting farmers, production and marketing society, processors of Chinese medicine decoction pieces, terminal consumers and middle sales section whichis made up of whole sale and retail markets and manufacturing enterprises of Chinese patent medicine. This article also proposed the suggestions about quality safety of Chinese medicine decoction pieces through quantitative methods in game theory.
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<p><b>OBJECTIVE</b>To compare therapeutic effects between surgical and conservative treatment for postoperative lumbar discitis.</p><p><b>METHODS</b>From January 2004 to January 2009, 41 patients (17 males and 24 females ranging the age from 37 to 68 years with an average of 53.6 years) with postoperative lumbar discitis were retrospectively studied and divided into two groups. There were 19 patients in operation group, 22 patients in conservative group. Clinical data and features,image data, laboratory examinations, antibiotics utilization, hospital stays and sequelae were recorded and analyzed. Visual analogue scales system (VAS) and Oswestry disability index (ODI) were applied to evaluate therapeutic effects.</p><p><b>RESULTS</b>All patients were followed up over 2 years. Imaging revealed good bone fusion and no occurrence of discitis. VAS score and ODI at 1 month, 1 year and 2 years were significantly improved after treatment (P < 0.01). While VAS and ODI in operation group at 1 month were improved more than that of conservative group (P < 0.01), and there was no significant difference between two groups at 1 year and 2 years (P > 0.01).</p><p><b>CONCLUSION</b>Surgical and conservative treatment for postoperative lumbar discitis is effective. Surgical treatment is superior to conservative treatment in a short time, while conservative treatment can achieve long-term satisfactory curative effects.</p>
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Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Antibacterianos , Farmacología , Usos Terapéuticos , Discitis , Quimioterapia , Cirugía General , Vértebras Lumbares , Cirugía General , Complicaciones Posoperatorias , Quimioterapia , Cirugía General , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
The inclusion compound of amylose and salicylic acid (SA) was prepared by a sealed temperature control method, and the formation of the inclusion compound was confirmed by IR spectrum and powder X-ray diffraction. The kinetic parameters of dissociation of amylose/SA compound were studied by the nonisothermal method which was defined as a relationship between the dissociation ratio and time. The values of activation energy (Ea) and frequency factors (InA) were calculated by a nonlinear least-square method. In this study, the formation of the inclusion compound of amylose/SA was confirmed by IR spectrum powder X-ray diffraction. SA existed in a molecule form in the spiral stouction of amylose. The dissociation of amylose/SA compound was attributed to first order reaction. The values of Ea calculated by the nor-isothermal method were 21.71 and 22.41 kJ x mol(-1) at heating rate 5 and 10 degrees C x h(-1), respectively. The corresponding isothermal method value of Ea was 22.17 kJ x mol(-1); the calculated InA values were 9.32 and 10.08 at heating rate 5 and 10 degrees C x h(-1), respectively. The corresponding isothermal method lnA value was 9.26. The results were in good agreement with Ea values and lnA values by isothermal method. These results indicated that the non-isothermal method described in this study could be adequately used for the stability study of inclusion compound and was a rapid and accurate method for the determination of kinetic parameters.
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The inclusion compound of amylose and salicylic acid (SA) was prepared by a sealed temperature control method, and the formation of the inclusion compound was confirmed by IR spectrum and powder X-ray diffraction. The kinetic parameters of dissociation of amylose/SA compound were studied by the nonisothermal method which was defined as a relationship between the dissociation ratio and time. The values of activation energy (Ea) and frequency factors (InA) were calculated by a nonlinear least-square method. In this study, the formation of the inclusion compound of amylose/SA was confirmed by IR spectrum powder X-ray diffraction. SA existed in a molecule form in the spiral stouction of amylose. The dissociation of amylose/SA compound was attributed to first order reaction. The values of Ea calculated by the nor-isothermal method were 21.71 and 22.41 kJ x mol(-1) at heating rate 5 and 10 degrees C x h(-1), respectively. The corresponding isothermal method value of Ea was 22.17 kJ x mol(-1); the calculated InA values were 9.32 and 10.08 at heating rate 5 and 10 degrees C x h(-1), respectively. The corresponding isothermal method lnA value was 9.26. The results were in good agreement with Ea values and lnA values by isothermal method. These results indicated that the non-isothermal method described in this study could be adequately used for the stability study of inclusion compound and was a rapid and accurate method for the determination of kinetic parameters.