Powder delivery methods

LiCalsi C, Christensen T, Bennett JV, Phillips E, Witham C (1999) Dry powder inhalation as a potential delivery method for vaccines. Vaccine 17 1796-1803. 

Microspheres intended for nasal administration need to be well characterized in terms of particle size distribution, since intranasal deposition of powder delivery systems is mostly determined by their aerodynamic properties and particle sizes. Commonly used methods for particle size determinations described in the literature are sieving methods [108], light microscopy [58], photon correlation spectroscopy [66], and laser diffractometry [25,41,53,93], The morphology of the microparticles (shape and surface) has been evaluated by optical, scanning, and transmission electron microscopy [66, 95],... 

Selection of the appropriate route of administration and delivery device is critical for the commercial success of a drug product. Although injections are the most efficient delivery method for proteins, they are not always the most suitable from the patient s perspective. Few routes of administration (IV, IM, SC, pulmonary, and topical for local delivery) have been successful to date with protein therapeutics because of the size and complexity of the protein structure. Consideration of the bioavailability via a given route must be made when determining the dose required. Use of a delivery device such as an implantable pump, needle-free injector, or dry-powder inhaler may yield a product with a commercial advantage over a competitor s product. 

Inhalers. Various aerosols can deliver liquid drug formulations. The hquid units are inserted into the device which generates the aerosol and delivers it directly to the patient. This avoids any problems associated with converting proteins into powders. This method has applications in delivery of morphine and insulin. 

Method 1 (with acetyl chloride). Equip a dry 500 ml. round-bottomed or bolt-head flask with a reflux condenser, and fit the top of the condenser with a two hole cork, one opening for a separatory funnel and the other for a delivery tube connected to an inverted funnel which dips just below the surface of about 200 ml. of water in a beaker (compare Fig. II, 13, 8). Place 40 g. of anhydrous, finely-powdered aluminium chloride (see Section IV,2) and 88 g. (100 ml.) of dry A.R. benzene in the flask and cool the latter in a bath of cold water (not ice water since benzene may crystallise). Through the separatory funnel at the top of the condenser add 29 g. (27 ml.) of redistilled acetyl chloride slowly during half an hour and shake the flask frequently to ensure thorough mixing of the... 

The original method uses the classical weigh powder, dilute volumet-rically scheme. In order to improve the efficiency and at the same time guarantee delivery of results of optimal quality, an extensive review was undertaken. 

Gather important information the agent used was it aerosol, liquid, gas, powder or vapor location method of delivery do you have the necessary personal protective equipment (PPE) to deal with the hazard, or have you called for assistance by a specialized team are you sure that anyone who enters a contaminated area has the proper PPE and is trained in its use be sure to establish control — keep all victims, non-victims and bystanders at the crime scene (if there is any suspicion of an attack) until it is determined who among them may be a terrorist or a witness perform decontamination, triage if necessary, isolation, quarantine, search and locate evidence, maintain chain of control, and collect samples. 

Powder inkjet delivery, fabrication method for inorganic materials, 7 415t Powder metallurgy (P/M), 26 127 copper, 7 698... 

The data in Table 8.2 are taken from a study reported by Hindle et the purpose of which was to determine whether a new dry powder inhaler (DISK) was equivalent to a traditional metered-dose inhaler (MDI) in its ability to deliver doses of a bronchodilator to the lungs of volunteers. The data are the percentages of an inhaled dose of salbutamol recovered in a urine sample taken 30 min post-inhalation for each method of delivery in nine volunteers. Ameasure of treatment effect is the difference in percentages within volunteers, shown in the fourth column. Of these differences seven are negative and two are positive (fifth column) and the question we need to answer is how likely is it that if there is no difference between the inhalers, we would see this degree of imbalance between negatives and positives ... 

In the aerosol solvent extraction system (ASES), the protein is dissolved in a compatible solvent (i.e., water or DMSO) and then introduced by atomization into supercritical CO2 (12,13). The solvent is extracted from the droplet, and the protein precipitates to form particles with appropriate sizes for pulmonary delivery (see Note 3). CO2 is then removed by venting off and the particles are collected. Insulin powders (see Note 4) made by this method possess a mean geometric diameter of 9.6 xm, and 22% of the powder was in the respirable range (0.5-6 p,m) (12). 

Experiment 85. — Prepare an apparatus like that shown in Fig. 23. Fill the ignition tube half full of a mixture of copper oxide (6 parts) and powdered wood charcoal (i part) introduce the mixture by the method described in App. A, ii. Arrange the apparatus as directed in Exp. 12. The delivery tube iu this case, however, should dip into a small dish of lime water. Heat the whole ignition tube gently at first increase the heat gradually, and finally heat strongly that part... 

Novocain is absorbed rapidly and begins to act within two to five minutes. The duration of the anesthetic effect usually lasts one to two hours, depending on the method of delivery, concentration of the solution, and the individual patient. Sometimes novocain is mixed with a drug called a vasoconstrictor. A vasoconstrictor constricts the blood vessels, reducing the flow of blood, which slows the rate of absorption so that the anesthetic effect lasts longer. Novocain is an odorless, white crystalline powder that is water soluble. It is available as a prepared solution as either pure or, depending on its intended use, mixed with other drugg. 

The delivery of pharmaceutical aerosols as a dry powder is no longer perceived as the second best method to deliver drugs to the lung. This is because of the mounting technologies, which are capable of making stable powders of respirable size and devices competent to deliver accurate doses and versatile payload. 

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