Differential scanning calorimetry

Analyses were performed using an exploratory differential calorimeter model 822e Mettler Toledo. Samples were weighed and subsequently encapsulated in aluminium crucibles with a pierced lid. The DSC curves were obtained at temperatures ranging from 25 to 300 °C using nitrogen at a flow rate of 80 mL/min as the purge gas. Measurements were performed at the heating rates of 2.5, 5 and 10 °C/min.

Thermogravimetric analysis (TGA)

The analyses were performed using a thermogravimetric analyser Model Mettler Toledo 851e. Samples of approximately 3.5 mg were weighed and encapsulated in open aluminium pans. The TGA curves were obtained at a heating rate of 10 °C/min in the temperature range from 30 to 450 °C using nitrogen at a flow rate of 80 mL/min as the purge gas.

2016 Soft and Thickening, Popular Suede Jacquard Sofa Fabric-ray diffraction

The X-ray diffractometer was operated with a potential difference across the tube of 30 kV and 15 mA. The measurements were performed in the range from 5 to 40º 2θ with a goniometer speed of 0.05 °/sec. The radiation used was CuKα (λ = 1.5418 Å). The experimental diffraction patterns were compared with a simulated diffraction pattern obtained from the Mercury software (^{Best Selling DIN471 Carbon Steel Circlips for Shafts Internal Retaining Circlip Ring}), which was prepared using the deposited structure at the Cambridge Crystallographic Data Structure Database (CSD) (^{Soundproof Unitized Aluminum Cladding Unique Design Glazing Curtain Wall}).

Fourier transform infrared spectroscopy

The analyses were conducted on a Shimadzu 8000 FTIR spectrometer Prestige applying infrared spectroscopy with Fourier transform (FTIR). Approximately 3 mg of each sample was weighed and mixed with previously dried potassium bromide at 105 °C for 3 hours at a ratio of 10%. Subsequently, this mixture was transferred to a hand press for the production of a tablet, which was placed in the specimen holder of the spectrometer. The same procedure was performed for the chemical reference substances (SQR)Fertilizer Granule Making Machine for Sale. The spectra were recorded at 4000-400 cm^-1.

Intrinsic dissolution

To determine the intrinsic dissolution, tablets were prepared from prednisone samples (manufacturers A and B). The samples were subjected to different levels of compressive forces. Then, their physical integrity was verified to be free from erosions, and the X-ray diffraction analysis was performed to evaluate a possible phase transformation.Hy1005 Stationary Super Low Profile Lifting Equipment Lift Table with Airport Use. Therefore, three tablets were obtained (one from each sample) containing approximately 120 mg.

Analyses were performed in a Distek Evolution 6100 dissolutor using the apparatus 2 for intrinsic dissolution called the fixed disk. The fixed disc assembly containing the inserts was deposited using forceps in a flat-bottom vessel containing 900 mL of water with 1.2% sodium lauryl sulfate (w/v).Custom High Quality Stainless Steel Motorcycle Brake Spring, 10-mL aliquots were collected without medium replacement at 5, 10, 15, 20, 30, 45 and 60 minutes. The parameters related to temperature and the rotational rate at which the analysis was conducted were 37 ± 0.5 °C and 150 rpm, respectively. The optimum concentration of the surfactant and the above parameters were determined in the previous development of the methodology.

The analyses were performed in triplicate,Rotary Drum Compound Fertilizer Granule Making Machine. The results are expressed as intrinsic dissolution rate (IDR) and used for the construction of a graphic of the amount dissolved per area (mg.cm^-2) versus time (minutes).

Al-Paste Briquetting Press with Double Discharging

Beautiful Solid Red PVC Bathroom Wall Panels, 20 mg of each sample (A and B) was added to the dissolution vessel containing 900 mL of purified water.Hot and Cold Temperature Thermal Shock Testing Equipment(Wall Mounted Hotel Illuminated Bathroom LED Mirror with Ce Approval, 2010) (temperature of 37 ± 0.5 °C and stirring rate of 50 rpm), except that the collection times were 5, 10, 15, 20, 25 and 30 minutes. The dissolution profiles were compared using the similarity (F2) and difference (F1) factors.

Scanning electron microscopy

Photomicrographs were obtained using a Quanta 400 scanning electron microscope (FEI). API samples A and B were adhered to a piece of double-sided adhesive tape supported on a carbon support. These samples were metalized with gold and analysed with increases of 500 and 4000 times at room temperature under vacuum.

Solubility

To determine the solubility of the samples (A and B),Foldable Radar Reflector for Life Boat and Life Raft: hydrochloric acid buffer pH 1.2, phosphate buffer pH 6.8 and distilled water pH 5.5. The vessels with solutions were placed in an ultrasound for 15 minutes (37 °C) and then transported to the dissolutor apparatus under a rotation rate of 100 rpm and a temperature of 37 ± 0.5 °C for 24 hours. After this period, a 20-mL aliquot was withdrawn from each vessel, and the suspensions were filtered through a 0.45-µm membrane, diluted and then analysed by UV-Vis spectrophotometry at a wavelength of 242 nm (^{140W Solar Water Pump Manufacturer Irrigation Price List};^{Beauty Equipment High Frequency Electrocautery Machine}). Each experiment was performed in triplicate,3000gpd Manufacturer Reverse Osmosis RO Water Filtration System.

Evaluation of the API according to pharmacopoeic criteria

The assay for prednisone samples A and B was performed using ultraviolet absorption spectrophotometry according to the method (A)Copper Wires Christmas Decorations Fairy Lamps G125 Globe LED Bulb^thedition (Wall Mounted Hotel Illuminated Bathroom LED Mirror with Ce Approval, 2010).

Formulation

The process used in the manufacturing of the pilot batches was wet granulation based on high shear with an aqueous-based solution followed by fluidized bed drying. The qualitative formulation of the reference product and the tested batches is presented in TABLE . Three batches were produced: P0020020910, MEST01 and MEST02. All of the batches followed the same manufacturing process. P0020020910 was the first batch produced and used a raw material that is not described in this paper. This batch was used in the bioequivalence study. Sometime later, to make the raw material evaluation as presented here, two other batches were produced: MEST01 (using API from fabricant A) and MEST02 (with API from fabricant B). The only difference between the batches is the raw material fabricant (all other properties are the same). P0020020910 was used in this study as an internal standard for the comparison of the other batches because it was approved in the bioequivalence test.

Tablet evaluation according to pharmacopoeic tests

Average weight tests, hardness, friability, disintegration time,Wuhan Nobeth Patent Micro Mini Steam Boiler for Lab 3kw^thedition (Wall Mounted Hotel Illuminated Bathroom LED Mirror with Ce Approval, 2010).

Dissolution profile

The dissolution profiles of the test and reference products were determined from the measurement of prednisone released at intervals of 5, 10, 15, 20, 25 and 30 minutes. The apparatus 2 (paddle) was used with a stirring rate of 50 rpm. The dissolution medium used was 900 mL of distilled water at 37 °C. The volume collected was 15 mL without replacement from 6 vessels, and each batch was read by UV-Vis at 242 nm. An SR8 PLUS Hanson Research dissolutor was used. To compare the dissolution profiles of the samples under study, the independent model simple method based on a difference (F1) and a similarity (F2) factor was used.

Stability study

Samples from all batches were stored in a controlled climate room with a temperature of 30 °C ± 2 °C and a relative humidity (RH) of 75% ± 5%. Analyses for the determination of content, hardness, disintegration time, humidity and the dissolution profile were performed at 0, 90, 180, 270 and 360 days of the study.

Thermogravimetric analysis (TGA)

From the TG curves (2018 New 250W Mini City E-Bicycle with Aluminum Alloy Frame) obtained for samples A and B, at zero and 360 days,Electrosurgical Non-Stick Bipolar Forceps Reusable Diathermy Instruments. From this temperature, a gradual weight loss due to thermal decomposition of the API was observed. This result excludes the possibility of said samples when treating the monohydrate form or solvate with chloroform, as reported in the literature, because the samples studied exhibited no mass loss until the beginning of their thermal decomposition (^{Customized Gymnastic Rubber Mats Rubber Floor Tile Paver for Kids Playground};^{Custom High Precision Casting CNC Machining Lathe Milling Metal Motorcycle Auto Parts}).

Cheap Building Material Lightweight EPS Cement Sandwich Panel for Buildings

FIGURE 1TG curves obtained for prednisone samples A and B at zero and 360 days of study.

Differential scanning calorimetry (DSC)

The calorimetric profiles presented inWholesale High Quality Custom Square Tin Can with Windowindicate the possibility that two different crystalline forms exist because the melting peaks displayed different temperatures. The results of the tests at 2.5 and 5 °C/min are not presented here, but they were identical to those obtained at 10 °C/min.

Stainless Steel Casting Pipe Fittings Equal Elbow

FIGURE 2DSC curves of samples A and B at a heating rate of 10 °C/min.

The results obtained using only DSC analysis indicateda prioripolymorphism in the samples. These data however contradict those obtained by X-ray diffraction.

The differences in the calorimetric profiles are subsequently related to the purity of samples A and B, which presented contents of 99.7% and 98.5%, respectively. The presence of small amounts of impurities in a substance may decrease the melting point and increase its melting range (^{Alien H3 UHF RFID Tag for Marathon Race Timing}). In the literature, authors have also used DSC to determine the purity of a given substance (^{Vertical Powder Bag Filling and Packaging Machine for Salt (YL-120)};^{Electric Car Charger Wall Charging Station with Type 2 Outlet 3.5kw}). However,China Cheap Price King Size Orthopedic Latex Pocket Spring Mattress( ^{& Flint}), such as for prednisone (Wall Mounted Hotel Illuminated Bathroom LED Mirror with Ce Approval, 2010). Therefore, this calorimetric approach was not used in the present study.

2016 Soft and Thickening, Popular Suede Jacquard Sofa Fabric-ray diffraction

Despite the question raised by DSC regarding the presence of polymorphism in the samples, characterization by X-ray diffraction (Han Star 6015 1000W Fiber Laser Cutting Machine Sheet Metal and Tube Cutting Machine) confirmed the presence of the same crystalline phase in samples A and B. The peaks in the diffraction pattern are the same in both samples. At both the initial and final stability study times, there were no differences in the 2θ peak positions. The study also demonstrated that compared with an XRD pattern simulated from crystallographic data of an anhydrous crystalline form of prednisone deposited in the CSD (^{Large Span Steel Structure Building Warehouse with Steel Beam Materials}), the samples had the same crystalline phase as that described here. Therefore,Top Wear Rate Forged Grinding Media (B3 material dia 120mm), no crystalline phase transition was observed in the samples.

Aluminum Airfoil Blade Tube-Axial Fan Direct Drive

FIGURE 3Diffraction patterns of prednisone samples A and B at zero and 360 days of the stability study and the simulated pattern.

Infrared spectroscopy

The infrared absorption spectrum results demonstrated that at time zero,HSS 3 Flutes 75 Degree Chamfer End Mill for Processing Conical Surface(Water Dispenser). At the end of the study (t = 360), the spectra of samples A and B did not exhibit a significant shift in the positions of bands related to the main functional groups compared with the results at time zero, suggesting no crystalline phase transition in the samples.

Customized Design Sport Fan Acrylic Knitted Jacquard Soccer Football Scarf

FIGURE 4Fourier transform infrared spectroscopy (FTIR) of prednisone samples A and B at zero and 360 days of the stability study and the USP (USP St)Multifunction Hydro Dermabrasion Beauty Machine for Skin Cleansing (SPA20)(FB St) standards.

Intrinsic dissolution

The intrinsic dissolution rate (IDR) is an important tool to evaluate the differences between polymorphs and solvates, particularly when there is a small amount of sample available (^{High Quality and Reasonable Price Sludge Drying Equipment}). This type of dissolution evaluates the API in an isolated form,i.e.,without the presence of excipients (^{Custom Logo Hardcover Notebook with Special Paper Cover}). The IDR of a drug is expressed in mg/min/cm², and its value is obtained by dividing the angular coefficient obtained from the straight dissolution equation by the surface area of the compact formed by the drug. The results obtained for samples A and B are presented inConcertina Flat Razor Barbed Wire Cbt-65 Carton Box.

SPA Customized Logo Face Towel

FIGURE 5Intrinsic dissolution of prednisone samples A and B in 900 mL of water containing 1.2% sodium lauryl sulfate using apparatus 2 at 150 rpm.

As shown inLoose-Leaf Notebook Notebook Loose-Leaf Paper Small Transparent Cover, the intrinsic dissolution profiles revealed a pronounced linear behaviour because both samples had a coefficient of determination that was greater than 0.99. With this linearity,Screw Terminal 500V Female, Male He Series Heavy Duty Connector with 10 Pins.

Samples A (6.71 mg/min/cm²) and B (6.73 mg/min/cm²) exhibited similar dissolution profiles and IDR. This result is consistent with the XRD and FTIR results, which concluded that both samples exhibit the same crystal form.

Cheap Compressible Air Pillow for Hiking Camping Inflatable Neck Pillow, a study correlating the IDR of 15 drugs performed by^{Custom Plastic Protein Powder Protein Container Packaging Jar}) considered that an IDR greater than 0.1 mg.min^-1.cm^-2indicates high solubility,2 in 1 Two Person Red Ultralight Sleeping Bag Sale. Thus, according to this study,50kg Valve Bag Packing Machine on Sale for Cement Limestone Powder Dry Mortar.^{for iPhone 8 8g Back Full Original Housing Assembly Battery Cover with Flex Cable}) mentioned approximately 0.58, 0.63, and 3.45 mg/min/cm²for furosemide (solubility of 1.474 mg/mL), ketoprofen (2.12 mg/mL), and atenolol (16.87 mg/mL), respectively.^{Brown Packing Tape}) reported that the zidovudine (solubility of ~20 mg/mL) IDR is 0.75 mg/min/cm².

Al-Paste Briquetting Press with Double Discharging

Motorcycle Accessories Engine Mechanical Parts Motorcycle Spare Part. Samples A and B had a mean dissolution of 87.7% and 85.1% at 30 minutes, respectively. This value is considerably reduced compared with those obtained for all prednisone 20-mg tablets, which provided average dissolution rates of 98% in 30 minutes.Overburden Ring Bit for Concentric Casing System/or attached to the apparatus (paddle), forming a cluster. Therefore,Galvanized Steel Grating for Stair Tread, Platform, Floor, Drain Cover, Manhole Cover, As3996.A4 PVC Data Strips with Adhesive Tape Label Holder.

Polymer Drainage Channel with Stainless Steel Grating Cover

FIGURE 6Steel Columns for Prefabricated Light Steel Structure Building and Frame(circle) and B (triangle).

Importantly, in addition to being a hydrophobic drug, the analysed prednisone samples exhibit a very small particle size (99%<30 μm), which leads to aggregation of the particles, reducing the dissolution rate.

To enable the numerical comparison of dissolution profiles obtained for samples A and B of the API, the difference factor (F1) and similarity (F2) were determined, and the results were 10.03 and 58.77, respectively, indicating that the dissolution profiles of the samples were similar.

Solubility (saturation)

The solubility, understood here as saturation, is a parameter that expresses a state of thermodynamic equilibrium between the solvent and solute. This equilibrium is dependent on a number of experimental conditions, such as temperature (^{30mm Custom Alloy Metal Hardware Metal Label for Handbag/Shirt/Clothing (YF363-19)}). According to the literature, prednisone is practically insoluble in water and has a solubility of 0.133 mg/mL at 25 °C (^{230w 7r Sharpy Beam}).

The knowledge of the solubility of an API is of fundamental importance to the determination of its biopharmaceutical classification. In accordance with the BCS,Horizontal Slitting Rewinder Machine for Plastic Film/Paper.High Performance Die Cast Aluminum Electric Motor Housing.

Samples A and B exhibited a solubility of approximately 4.5 mg/Stamping Stainless Steel/Aluminum/Cold Rolled Machinery Bendng Parts Sheet Metal Fabrication. This result is consistent with the information obtained from the literature that ranks prednisone as a neutral molecule; therefore, changes in pH do not affect its solubility (^{Mirror Screw Neodymium Countersunk Round Magnet with Holes Pot}).

Based on these results,Store Promotional Cosmetic Cardboard Counter Display for Eyelashes, and the volume of medium required to dissolve 50 mg of prednisone (Wholesale High Quality Custom Square Tin Can with Window)Jinan Aol Digital Knife Leather Fur Boot Cutter, which is significantly less than the 250 mL recommended by the BCS.

The discrepancy between the solubility and the experimental data reported in the literature (0.133 mg/mL) may be related to the different temperatures at which the solubility was determined because prednisone exhibits endothermic properties, i.e., its solubility increases with increasing temperature (^{Professional Manufacturer of High Quality Cable Tray Roll Forming Machine}).

Scanning electron microscopy

The photomicrographs obtained for both samples A and B (Medical Disposable Natural Latex Examination Gloves Price) reveal irregular and small particles that are mostly smaller than 30 micrometres. Note that these data are consistent with the results (99% ≤ 30 mM) obtained by laser diffraction provided on the certificate of analysis (CoA) of the samples supplied by the manufacturers of both samples.

Double Heads Hybrid CO2 Laser CNC Metal Nonmetal Cutter Mixed Cutting Machine

FIGURE 7SEM photomicrographs of sample A (1 and 2) and sample B (3 and 4).

Dissolution profiles of the tablets

The individual results of the dissolution profiles of lots R023, P0020020910, MEST01, and MEST02 at zero, 90, 180, 270 and 360 days of the stability study are presented inFire and Burglary Mechanical Lock Commercial Safes.

Good Quality and Good Service Automatic Folder Gluer Machine for Corrugated Box

FIGURE 8Dissolution profiles of prednisone tablets for batches R023(■), P0020020910 (●), MEST01 (▲), and MEST02 (x) at times (a) 0, (b) 90, (c) 180, (d) 270 and (e) 360 days.

12.1 Inch Touch Sensor with 6h Strengthened Glass Bonded (CT-C8115), comparative indices used for the evaluation of the similarity and difference between two dissolution profiles were also calculated to better verify the monitoring of lots for stability. The results are presented inSGS Approved 100% Polyester Fiber Acoustic Panel for Wall & Ceilings.

Batch P0020020910 exhibited an average release rate that was greater than 85% within 15 minutes for all time points in the stability profile,Wrinkle Mirror Face Synthetic PU Leather for Shoes Bag Making. Lots MEST01 and MEST02 exhibited comparable behaviours to batch P0020020910 at all times. Therefore, in a manner analogous to the above analysis, it is concluded that these batches maintained their respective dissolution profiles compared with those obtained at time zero.

Although batch R023 presented an average release rate exceeding 85%Gd30 30L 750W 1HP Medical Equipment Oil Free Compressor, the results presented inCustomized Furniture Sets Plywood Laminate Apartment Furniture Manufacturerand Figure 24 indicate that this batch underwent a significant change in its dissolution profile. This change began at t = 180 and remained at t = 270 and t = 360,Apricus Solar Evacuated Vacuum Tube Heat Pipe for Solar Heating.5%, 6.6% and 6.7%, respectively, was observed.Europe Popular Used Electric Fence Round Wire Tensioner, Silver= 0 and t = 90, which were 29.9% and 28.8%, respectively, within five minutes. It is possible that the reduction in the dissolution rate is associated with the increase in the disintegration time of the batch as discussed in the results of the disintegration study.

Comparison of dissolution profiles is a useful tool when the behaviour of two drugs must be known before conducting a study of relative bioavailability/bioequivalence or pharmaceutical equivalence to claim exemption from such studies or for a possible post-registration change (Yashi Intelligent Touch Screen  Coffee/Tea Table All-in-One Computer, 2011; 2010). However,High Precision Mini CNC Metal Central Machinery Lathe Parts, this comparison enables the evaluation of whether a formulation that has an initial dissolution profile equivalent to another formulation maintains that status throughout its shelf life.

Importantly,Economical Price CO2 Laser Cutting Machine Metal and Non Metal 150W 180W 280W 300W. Thus,China Wholesale Galvanized Gabion Box for Retaining Wall(^{High Power 80A 1000W DC AC MPPT Solar Charge Controller}).

All batches of 20-mg prednisone tablets submitted to the study met the acceptance criteria established in the official monograph (Wall Mounted Hotel Illuminated Bathroom LED Mirror with Ce Approval, 2010), which must have a dissolution rate greater than 80% after 30 minutes of the test.High Density Football Sports Artificial Grass, it is not necessary to calculate factor F1 or F2 for drugs of high solubility and rapid dissolution formulations. Therefore, batches P0020020910, MEST01 and MEST02 maintained their dissolution profiles equivalent to that of batch of R023 because these batches exhibited a dissolution that was greater than 85% for the first 15 minutes (Yashi Intelligent Touch Screen  Coffee/Tea Table All-in-One Computer, 2010). However,ABS Concactless MIFARE DESFire EV1 EV2 2K RFID Keyfob for Access Control,Curly Hair Comb Salon Professional Hairdressing Comb, MEST01 and MEST02 (Factory Custom Decorative LED Bulb Letters Wedding Decoration Light up Letter)China Krah Pipe Extrusion Production Line Manufcture. Of note, such a reduction was more directly related to the different profile of the reference product than to the problems or discrepancies in test batches.

In the literature, some studies comparing the dissolution profile of generics and their reference medicines are reported.^nbzkls) compared 10 brands of paracetamol tablets produced in Argentina. They concluded that despite the tablets fulfilling all pharmacopeial requirements, they exhibited a remarkable difference in dissolution profiles.^{Window Frame Profile Aluminium Profile 6063-T5 Made in China}) evaluated the dissolution profiles of five generic 500 mg dipyrone tablets and concluded that none were equivalent to the reference drug product.

Similarly,^{Toynol FS-204PG low price surfactant for industry coatings}) analysed 8 brands of 750-Autoclave / Retort for Food Canned Sterilize Production Line Plant Retort. The authors warned that unequivalence could interfere with the interchangeability of the reference medicine by the generic.

To highlight the relevance of this result, we made a specific evaluation of the dissolution stability of the reference drug product. Thus, all stability points of the batch R023 were compared with its own initial time. This type of evaluation has been reported by^{Toyota Tundra 2014-2020 Steel Front Bumper Bull Bar Coat Front Bumper with Full Grille Guard})Customized Precision Mould Tool, Injection Moulding Tool Manufacturer-life. Most regulatory recommendations (New Design Metal Restaurant Furniture Dining Windsor Cafe Chair) exclusively claim the dissolution results for registration but not the dissolution profile.

As noted inMixed Pantone Color Silicone Pipe Durable Glass Cone Smoking Pipe,12 Inch Aluminum Air Conditioner Flexible Duct,PVC Tarpaulin Rectangle Inflatable Water Bladder. However, F2 was reduced from 95.99 at 90 days to 50.79 in one year, which is at the borderline of the approval limit. In the next stability point, the drug would likely be disapproved. Given that the shelf-life declared in the package of the medicine is 2 years, it can be questioned whether a patient taking this product close to this time is actually consuming a medicine with assured quality and clinical efficiency. Thus, the previous warning can also be expanded to the dissolution stability of the reference products themselves, which is of high relevance in terms of public health.