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The film is formed by evaporation of the solvent discount 100 mg viagra sublingual with visa, and the process temperature de- fines the evaporation speed purchase 100mg viagra sublingual otc. If the solvent is evaporated too fast best viagra sublingual 100 mg, free volume in the polymer film will be generated purchase 100 mg viagra sublingual visa, and aging Concentrated Dense polymer effects can occur as described above. Highly diluted polymer chains polymer chains film In general, removing volatile sub- in solution in solution stances (i. This effect should not be con- Application Difficulty * Remarks fused with aging of the polymer film. Such particles will meet randomly and Multilayer coatings 3–5 Difficulty increases with increasing number of layers and if form larger granulates by sticking to each nozzle cleaning is required other. In the case of coating, exactly the op- *1=least difficult, 5=most difficult posite is required. No particles should meet in a wet state because of the risk of forming agglomerates. This reduction Organic solution, high viscosity in spray rate will in turn increase overall Aqueous solution, low viscosity, process time. Compared to Organic solution, low viscosity, suspended particles top-spray coaters, the mechanical set- suspended particles up of the bottom-spray coaters is better Dispersion, low viscosity High shear forces can lead to coagulation for preventing agglomerates. The most Dispersion, low viscosity, 3–5 High shear forces can lead to coagulation, liquid should commonly known bottom-spray system suspended particles be in motion to avoid settling of suspended particles is the Wurster coater. It was invented in *1=least difficult, 5=most difficult 1953 and continued to be the state-of- the-art for 35 years. Aging or further coalescence can faced serious issues with agglomeration, regular nozzle block- occur if the film is stored at temperatures above the T. Duringg ages, and necessity of splitting batches if higher weight gains aging, free volume is reduced, which typically leads to lower were required. Such product losses, extremely long processes, and difficult scale- polymer films need special postprocessing to accelerate the up procedures, which drove demand for the development of a aging process and ensure stable storage formulations if the new generation of coaters. Super Refined Castor Oil is an ideal solvent for multiple dosage forms, as well as an excellent lipid vehicle Multi-compendial Compliance for injectable formulations. Both follow the princi- Mini tablets 1–3 Narrowest particle size distribution, good flowability, tendency to pal idea of the Wurster coater but elimi- break depending on tablet formulation nate most of its limitations through me- Granules, high shear 2–3 Variation in particle size, good flowability, slight tendency to break chanical optimizations and improved Granules, fluid bed 3–5 High variation in particle size, good flowability, high tendency to break fluid dynamics. These machines elimi- nated many of the shortfalls in earlier Crystals 1–5 Difficulty of crystals is hard to predict as there is huge variability in size, shape, brittleness and hardness; suitability of crystals as systems and were technology leaders substrate needs to be carefully evaluated for the following decades. Hüttlin’s Modern Bottom <125 State of the art Kugelcoater and Aeromatic-Fielders Tangential FlexStream marked the next stage in de- velopment by eliminating the need for columns. Gun-to-product distance (cm) 7 19 19 The systems’ performance is similar to the Tube diameter (mm) 1. Inlet air temperature (°C) ~43 ~48 ~48 Outlet air temperature (°C) ~23 ~24 ~23 Application matrix Product temperature (°C) ~22 ~23 ~22 Because particle coating is a highly com- plex process, thorough knowledge about Spray rate (g/(min*kg)) 6-14 5-13 3-7 the type of application, coating liquid, Inlet air humidity (g/kg) ~4. An ap- Outlet air humidity (%]) 52–74 56–78 45–79 plication matrix was developed from the Spraying time (min) 95 113 185 experience of numerous particle-coating projects to assist in rating the difficulty connected with coating. For sterile manufacturers, the n Managers, group leaders, or quality bar is even higher as sterile manufacturing has become directors external or third-party increasingly more complex due to the increase in the number manufacturing of poorly stable compounds, new technologies, unit opera- n Managers, group leaders, tions, and controls. Purified water was used as diluent; the 70 solid content of the spraying suspension 60 was 20%. Differences in drying air capacity and Figure 4: Six month storage-stability test of pilot-scale batch. An F-test (95% signifi- 6 months 40/75 cance level) showed no difference between 10 the release profiles of the different scales 0 0 1 2 3 4 5 6 7 8 9 10 11 12 or during the six-month storage stability Time (h) test (see Figures 3 and 4). A multi-layer coating applica- tion, for which D=5, involved a functional coating followed Conclusion by in-process curing with purified water, for which D=1. The From a processing point of view, most coating applications are coating liquid was a low viscous dispersion with suspended similar. The application matrix equation resulted cally depending on the core materials, the type of coating fluid, in a cumulative difficulty score of 30. The applica- With this score, the work could have been conducted in a tion matrix helps identify the optimal coating process and equip- Wurster or modern bottom-coating system, but a tangential sys- ment, which, along with an understanding of how the components tem (Aeromatic-Fielders, FlexStream) was chosen because of its interact, can ensure successful particle coating. No matter the project, it’s our commitment to building a great relation- ship that makes Metrics unique. And like any great relationship, ours are built on communication, collaboration and something that must truly be earned: your trust. Cabelka uality by design (QbD) is a systematic approach to de- signing and developing pharmaceutical formulations and manufacturing processes to ensure predefined Qproduct quality (1). This proactive and enhanced understand- ing supports efficient pharmaceutical product development. This article attributes on the final drug product is integral to presents a QbD approach to determine the effect of material at- quality by design (QbD). The authors examine the tributes on both the physical properties and in vitro drug-release effect and interaction of variations in the material performance of the matrix tablets. The study demonstrated consistent physical properties for direct- compression blends and subsequent tablet cores, irrespective of the Methocel concentration or drug included. In vitro drug release, however, showed greater sensitivity to material-attribute variability at lower polymer concentration. The importance of QbD QbD is a systematic approach to pharmaceutical development that results in increased quality and reduced costs. Robertson*, PhD, is global quality-by-design processes to ensure predefined product quality (1). Building quality into drug prod- Tiwari, PhD, is regional technical manager at Colorcon Asia Pvt. At both 15% and 30%, drug- release profiles were similar ( = 63 and 68, respectively) despite variations in Methocel viscosity (see ). Use of higher polymer concentration (30% w/w) resulted in lower tablet-to-tablet variability as indicated by the error bars. All matrix tablets had comparable hardness, tensile of hypromellose on the drug-release profiles is shown in Fig- strength, and friability values. Here too, at both 15% and 30% polymer concentration, for all formulations with 15% w/w polymer concentration, in- the drug-release profiles were similar ( = 82 and 91, respec- dicating that the material attributes (i. At 30% polymer concentra- tion, the drug-release profiles were very similar ( = 95) despite variations in particle size. At 15% polymer con- centration, however, the batch with the larger particle size (low percentage through 230 mesh) gave a faster and dissimilar ( = 46) drug-release profile compared with the batch with the finer particle size (high percentage through 230 mesh) of the polymer. In addition, tablet-to- tablet variability was higher in the formulation contain- ing the coarser particle size in comparison to the center point and fine particle-size formulations. Higher polymer concentration may decrease sensitivity of the formulation to minor variations in raw materials or the manufacturing process. Study results indicated that comparable physical properties were obtained for the- ophylline powder blends and compressed tablets at both 15% and 30% polymer concentration. The Certified Consultants have collectively brought more than 200 pharmaceutical products to market, including some of the world’s largest blockbusters, and are available to answer your questions directly in. The simulated batches follow normal distribution with a certain standard deviation (indicated along the X-axis).

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Now, Converting your Morphine into street quality Heroin (diacetylmorphine)Procedure: First, place some of your converted morphine into a metal spoon and add acetic anhydride and then cover with a piece of aluminum foil and bake in the oven at around 80 degrees Celsius, for at least 1 hour. When the substance is cold, you can move it to a burner (torch lighter) and just heat till you think its at about at least 80 degree’s and sniff a couple inches above it. It shouldnt sting your nose, if it does just heat it lightly some more until the smell goes away. Government edition of this publication and is herein identified to certify its authenticity. The Code is divided into 50 titles which represent broad areas subject to Federal regulation. Each title is divided into chapters which usually bear the name of the issuing agency. Each chapter is further sub- divided into parts covering specific regulatory areas. Each volume of the Code is revised at least once each calendar year and issued on a quarterly basis approximately as follows: Title 1 through Title 16.............................................................. The Code of Federal Regulations is prima facie evidence of the text of the original documents (44 U. These two publications must be used together to deter- mine the latest version of any given rule. These two lists will identify the Federal Register page number of the latest amendment of any given rule. Source citations for the regulations are referred to by volume number and page number of the Federal Register and date of publication. Publication dates and effective dates are usu- ally not the same and care must be exercised by the user in determining the actual effective date. In instances where the effective date is beyond the cut- off date for the Code a note has been inserted to reflect the future effective date. In those instances where a regulation published in the Federal Register states a date certain for expiration, an appropriate note will be inserted following the text. Code users may find the text of provisions in effect on a given date in the past by using the appropriate numerical list of sections affected. Incorporation by reference was established by statute and allows Federal agencies to meet the requirement to publish regu- lations in the Federal Register by referring to materials already published else- where. For an incorporation to be valid, the Director of the Federal Register must approve it. The legal effect of incorporation by reference is that the mate- rial is treated as if it were published in full in the Federal Register (5 U. Some of the elements on which approval is based are: (a) The incorporation will substantially reduce the volume of material pub- lished in the Federal Register. If you have any problem locating or obtaining a copy of material listed as an approved incorpora- tion by reference, please contact the agency that issued the regulation containing that incorporation. This index is based on a consolidation of the "Contents" entries in the daily Federal Reg- ister. The parts in these volumes are arranged in the following order: Parts 1–99, 100–169, 170–199, 200–299, 300–499, 500–599, 600–799, 800–1299 and 1300–end. The first eight volumes, containing parts 1–1299, comprise Chapter I—Food and Drug Administration, Department of Health and Human Services. The Code of Federal Regulations publication program is under the direction of Michael L. I (4–1–10 Edition) Part Page 129 Processing and bottling of bottled drinking water 319 130 Food standards: General......................................... The agency fore May 8, 1992, will be considered may grant the exemption, under such timely even though the applicable stat- conditions as it may prescribe by regu- utory provisions or regulations are not lation, if the agency finds that the yet in effect. State requirement will not cause any (3) The petitioner is an official of a food to be in violation of any applica- State having authority to act for, or on ble requirement under Federal law, behalf of, the Government in applying will not unduly burden interstate com- for an exemption of State requirements merce, and is designed to address a par- from preemption. Identify and give the exact wording of including a standard of identity, qual- the State requirement and give date it was ity, and fill. Identify the specific standard or regula- requirement but instead means that tion that is believed to preempt the State re- the State requirement directly or indi- quirement and the section and paragraph of rectly imposes obligations or contains the act that the standard or regulation im- plements. Documentation of State Requirement food container, that: Provide a copy of the State requirement (i) Are not imposed by or contained that is the subject of the application. Where in the applicable provision (including available, the application should also include any implementing regulation) of sec- copies of any legislative history or back- tion 401 or 403 of the act; or ground materials used in issuing the require- (ii) Differ from those specifically im- ment, including hearing reports or studies posed by or contained in the applicable concerning the development or consideration of the requirement. An explanation of the State requirement meet the general requirements of and its rationale, and a comparison of State §10. An explanation of why compliance with the State requirement would not cause a tioner may submit an original and a food to be in violation of any applicable re- computer readable disk containing the quirement under Federal law. The petition should contain in- mitting a disk should contact the Cen- formation on economic feasibility, i. To the extent possible, the petition Department of Health and Human Services, should include information showing that it 5630 Fishers Lane, rm. Identification of a particular need for in- under section 403A(b)of the Federal Food, formation that the State requirement is de- signed to meet, which need is not met by Drug, and Cosmetic Act to request that the Federal law. The petition should describe the Food and Drug Administration exempt a conditions that require the State to petition State requirement from preemption. Environmental Impact writing of the filing and docket number The petition shall contain a claim for cat- of a petition. Provide name and address of person, (5) Within 90 days of the date of filing branch, department, or other instrumen- tality of the State government that should the agency will furnish a response to be notified of the Commissioner’s action con- the petitioner. The availability for (g) If a State submitted a petition for public disclosure of a petition for ex- exemption of a State requirement from emption will be governed by the rules preemption under section 403A(a)(3) specified in §10. Name of firm against which action is menced an informal or formal enforce- anticipated (if applicable). Applied Nutrition, Food and Drug Ad- (d) The notification that a State sub- ministration, 5100 Paint Branch Pkwy. Name of product(s) covered by the notifica- This date will be the date of notifica- tion llllll tion for the purposes of paragraph (b) Reporting official, title, and telephone no. Copy of the label and labeling of the actions include warning letters, recalls, product.

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Unlike Arrhenius generic 100mg viagra sublingual visa, Lowry-Bronsted and Lewis acids and bases generic 100 mg viagra sublingual with mastercard, the Usanovich’s concept in a much broader sense includes all the oxidizing agents as acids and the reducing agents as bases order 100mg viagra sublingual otc, e purchase 100 mg viagra sublingual. According to the Lux-Flood concept—‘an acid is the oxide-ion acceptor while a base is the oxide donor’. Examples : (a) Organic substances : urea, sodium salicylate, diphenhydramine, emetine hydrochloride, meprobamate, paramethadione, pyrazinamide etc. The two methods, namely : direct titration method and residual titration method are briefly discussed as under : 4. In usual practice, the residual titration is accomplished by allowing to dissolve the substance under estimation in an accurately measured quantity of a standard solution of known strength present in excess and subsequently titrating the excess of the latter with another previously standardized solution. A good number of examples of this particular method shall be discussed in subsequent exercises. Cool and titrate with 1 N sulphuric acid using phenolphthalein solution as indicator. When the pink colour of the solution is discharged record the volume of acid solution required. Hence, each millili- tre of the total amount of 1 N sulphuric acid consumed is equivalent to 40. After complete dissolution, add methyl orange and titrate the excess of sulphuric acid with 1 N sodium hydoxide. Hence, each millilitre of 1 N sulphuric acid, 1 meq neautralized by the ZnO, is equivalent to 40. Thus, the percentage of zinc oxide present in the sample may be calculated as follows : (ml1 N) (ml2 N) meq. Cognate Assays Calamine ; Ephedrine ; Lithium carbonate ; Milk of Magnesia ; Magnesium stearate ; Sodium lactate Injection. However, two methods are generally adopted for the assay of acidic substances, namely : (a) Direct Titration Methods : It is accomplished by directly titrating an exact quantity of the acid, acid salt or other acidic substance with standard alkali solutions. As a general principle, the following guidelines may be observed carefully, namely : (i) the normality of the solution obtained by dissolving the acidic substance must be approximately the same as that of the titrant, (ii) the liquid acidic substance to be titrated must be brought to room temperature (25°C) before titration, because many indicators offer different values at different temperatures, and (iii) the quantity of acid to be taken should be calculated in such a manner that approximately 30 to 40 ml of the previously standardized base shall be utilized for the assay. Inorganic Acids—for these either methyl red or phenolphthalein may be employed as indicators and the alkali must be standardized with the particular indicator used. Procedure : Place 2 g of previously dried and accurately weighed sample of tartaric acid in a conical flask. Thus, the percentage of tartaric acid present in the sample is given by : ml l 0 07504. Thus, the percentage of busulphan present in the sample may be calculated as under : ml 0. Great care should be taken to avoid inhaling the particles of busulphan or exposing the skin to it. Cognate Assays Benzoic acid ; cellulose acetate phthalate ; chlorpropamide ; ibuprofen ; indomethacin ; nicotinic acid ; oxyphenbutazone ; phosphoric acid ; phenylbutazone and salicylic acid. In practice this method applies to such substances that normally react too slowly with the titrant because of their poor solubility which may be accomplished either by a heating process or by a precipitation method so as to convert the substance capable for reaction with the standard base. Repeat the operation without the substance being examined, the difference between the titrations represents the amount of 0. Describe the theory of ‘Acids and Bases’ with respect to the following aspects : (a) Lowry-Bronsted’s Theory (b) Lewi’s Theory (c) Usanovich Theory (d) Lux-Flood Concept. What do you understand by ‘direct titration method’ in the context of Aqueous Titrations? Discuss in details the procedure involved in the assay of : (a) Sodium carbonate (b) Sodium salicylate tablets. Justify the statement with the help of assay of the following pharmaceutical substances : (a) Zine Oxide (b) Milk of Magnesia. Rosenthal, D, and P Zuman, ‘Acid-Base Equilibria, Buffers and Titration in Water’, In Treatise on Analytical Chemistry, ed. Ahuja, S, Impurities Evaluation of Pharmaceuticals, Marcel Dekker, New York, 1988. Evidently, these compounds posed two vital problems of quality control, both in pure and dosage forms by virtue of their inherent characteristics, namely : (a) poor solubility, and (b) weak reactivity in aqueous medium. Initially, the above two problems were usually circumvented in the following manner : Example 1 : Amine salts—It is first changed to the water-soluble free base, extracted with an appro- priate organic solvent and treated with an excess volume of standard acid ; subsequently, the solvent was evaporated, and the remaining acid determined with a standard base. Example 2 : Sodium salts—It is first acidified to release the water-insoluble organic acid, extracted with a suitable organic solvent, the solvent was removed and the residue was subsequently dried and weighed. Example 3 : Nitrogen containing compounds—They are estimated by micro Kjeldahl’s Method. Nevertheless, such specific quantitative methods gave rise to certain serious anomalies and draw- backs. In order to overcome these shortcomings the non-aqueous titrations were introduced. The reason being that in aqueous medium and at higher Kb values (> 10–6) the solvent water competes progressively with the basic species in solution for the proton of the solvent. Hence, from the above definitions it may be implied that : (a) an acid : could be either an electrically neutral molecule e. H+ + A – Acid Basic Solvated Conjugate solvent proton base of acid Perchloric acid displays more strongly acidic characteristics than a weak acid, for instance : acetic acid when dissolved in a weakly basic solvent. Perchloric Acid : It is a very strong acid and when it is made to dissolve in acetic acid, the latter can behave as a base and forms an ‘onium ion’ after combining with protons donated by the perchloric acid. Pyridine, a weak base, when dissolved in acetic acid, the latter exerts its levelling effect and subsequently increases the basic characteristics of the pyridine. Therefore, it is practically feasible to titrate a solution of a weak base in acetic acid against a mixture of perchloric acid in acetic acid. Thus, a sharp end point is achieved which otherwise cannot be obtained when the titration is performed in an aqueous medium. In short, it is possible to titrate mixtures of two or three components selectively with a single titration by wisdom of the right choice of solvent for the non-aqueous titrations. Now add 30 ml acetic anhydride and make up the volume to 1 litre with glacial acetic acid and allow to stand for 24 hours before use. It usually undergoes a spontaneous explosive decomposition and, therefore, it is available always in the form of a solution. Add 25 ml of glacial acetic acid and attach a reflux condenser fitted with a silica-gel drying tube. It is, however, necessary to mention here that the same indicator must be used throughout for carrying out the standardiza- tion, titration and neutralization of mercuric acetate solution. Hence, it is always advisable to carry out standardization and titration preferably at the same temperature. In a situation where these temperature parameters cannot be achieved, the volume of titrant may be corrected by the application of the following formula : Vc = V [1 + 0. For the sake of convenience these typical titrations can be catego- rized into two broad groups, namely : (a) Acidimetry in Non-aqueous Titrations—It can be further sub-divided into two heads, namely : (i) Titration of primary, secondary and tertiary amines, and (ii) Titration of halogen acid salts of bases. Methlyldopa In general, the reaction taking place between a primary amine and perchloric acid may be expressed as follows : R. Calculations : The percentage of methyldopa present in the sample is given by : ml 0.

Biodegradable polymers tend to be used for injectable discount viagra sublingual 100mg mastercard, or implantable order viagra sublingual 100 mg line, drug delivery systems discount viagra sublingual 100mg free shipping. Once the coating polymer dissolves purchase viagra sublingual 100 mg otc, the drug is available for dissolution and absorption. Drug cores can be coated with polymers of different coating thickness, so that drug release can be delayed for certain periods, for example 1, 3, 6 and 12 h after administration. By using a dosage form incorporating a spectrum of different coating thicknesses, the overall drug release from the dosage form (as a whole, rather than from the individual microparticles) can adjust to give zero-order drug release. Since the size of the matrix decreases as the dissolution process continues, the amount of drug released also decreases with time. The decrease in drug release can be compensated in part by constructing a non-linear concentration profile in the polymer matrix. This strategy is used in the oral dosage form, Adalat, where the core of the dissolution matrix contains more drug than the outer layer. Microparticulates made of proteins, in particular albumin, are also widely used in the preparation of injectable drug carriers. The movement of water results in an increase in pressure in the solution and the excess pressure is known as the osmotic pressure. Osmotic pressure can used to pump out a drug at a constant rate from the delivery system. Device and formulation parameters can be controlled so that drug release is zero- order. An important consideration is that osmotic-controlled devices require only osmotic pressure to be effective, thus such devices operate essentially independently of the environment. Hence, in vitro drug release rate is often consistent with the in vivo release profile. Also, for oral delivery, changes in pH or ionic strength in the gastrointestinal tract will not affect the drug release rate. In parenteral therapy, the subcutaneously implantable, osmotic mini-pumps developed by the Alza Corp. Osmotic mini-pumps, such as the Oros osmotic pump, are also available for controlled 60 release via the oral route (see Section 6. They allow physicians and patients to precisely control the infusion rate of a drug. Externally programmable pumps can facilitate: • zero-order controlled drug release; • intermittent drug release. Ideally, a pump should deliver the drug at the prescribed rate(s) for extended periods of time and thus should incorporate a wide range of delivery rates, ensure accurate, precise and stable delivery, contain reliable pump and electrical components and finally, provide a simple means to monitor pump status and performance. A pump should also be convenient for the patient and thus should ideally be reasonably small in size and inconspicuous, have a long reservoir life and be easy to program. The biocompatibility of the device surface is also an important issue for consideration. Other safety concerns include danger of over- dosage, drug leakage and pump blockage. For example, drug release may be controlled by the way in which pH or ionic strength affects the swellability of a polymeric delivery system. More sophisticated systems incorporate specific enzymes which causes changes in localized pH or increases in localized concentrations of specific substrates such as glucose. The change in pH caused by the biotransformation of the substrate by the enzyme thereby causes a change in permeability of a pH-sensitive polymeric system in response to the specific biomolecule. Such systems may be used to modulate the release of drug through a controlled feedback mechanism. Site-specific drug delivery is desirable in therapeutics, in order to improve: • drug safety, as toxic side-effects caused by drug action at non-target sites are minimized; • drug efficacy, as the drug is concentrated at the site of action rather than being dispersed throughout the body; 61 • patient compliance, as increased safety and efficacy should make therapy more acceptable and thus improve compliance. In its simplest form, drug targeting can be achieved by the local administration of the therapeutic compound; this strategy is feasible even with conventional dosage forms. For example, if the site for desired drug action is the skin, the medication may be applied in ointment, lotion, or cream form, directly on the desired site. Direct injection of an anti-inflammatory agent into a joint is another example of site-specific delivery which is achievable without having recourse to a highly specialized drug delivery and targeting system. Sophisticated drug targeting technology is also available, particularly for oral and parenteral delivery. However, technology is not yet advanced sufficiently for the design of “magic bullet” drug delivery systems, proposed by Paul Ehrlich at the turn of the 20th century (see Section 1. For oral delivery, systems are available to achieve site-specific delivery within the gastrointestinal tract; for example, targeting the drug to the small intestine, colon, or gut lymphatics. Drug delivery systems available for targeted oral delivery include those that use enteric coatings, prodrugs, osmotic pumps, colloidal carriers and hydrogels; these technologies are discussed in Chapter 6. Technologies for targeted drug delivery are most advanced for parenteral administration. Such technologies are concerned with delivering drugs to specific targets in the body and also to protect drugs from degradation and premature elimination. They include the use of: • soluble carriers, such as monoclonal antibodies, dextrans, soluble synthetic polymers; • particulate carriers, such as liposomes, micro- and nano-particles, microspheres; • target-specific recognition moieties, such as monoclonal antibodies, carbohydrates and lectins. These technologies, and the various anatomical, physiological and pathological issues that pertain to their use, are discussed in detail in Chapter 5. Recent advances in biological and chemical sciences have led to the development of various “Smart” technologies to ensure more effective drug delivery and targeting of drugs to specific sites within the body. The advantages and limitations of these systems are discussed in detail in Chapter 16. Such systems are used to achieve site-specific drug delivery following parenteral administration. Release of the attached drug molecules at the target site can be achieved by enzymatic or hydrolytic cleavage. Larger complexes, some undergoing clinical trials, include drug conjugates with soluble natural, or synthetic, polymers. Nano- and microparticles Nanoparticles are solid colloidal particles, generally less than 200 nm. Such systems include poly (alky1- cyanoacrylate) nanoparticles used for parenteral drug delivery and targeting. Microparticles are colloidal particles in the micrometer scale, typically in the size range 0. Synthetic polymers, such as poly(lactide-co-glycolide), are widely used in the preparation of microparticulate drug delivery systems and also as biodegradable implantable devices. Natural polymers, such as albumin, gelatin and starch, are also used as microparticulate drug carriers.

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