The authors wish to acknowledge funding from the National Institutes of Health (R01AI155922). Microscopy was performed at the Chapel Hill Analytical and Nanofabrication Laboratory (CHANL), a member of the North Carolina Research Triangle Nanotechnology Network, RTNN, which is supported by the National Science Foundation, Grant ECCS-1542015, as part of the National Nanotechnology Coordinated Infrastructure, NNCI.

All animal experiments were conducted in accordance with the Animal Welfare Act and the Public Health Service Policy on Humane Care and Use of Laboratory Animals. The study protocol was approved by the Institutional Animal Care and Use Committee of the University of Tennessee Health Science Center. Healthy female BALB/c mice, ~6-8 weeks old, were administered the dry powder content of one dosator by intrapulmonary aerosol delivery for a pharmacokinetic study using spectinamide 1599 dry powders9. T...

Customizable Disposable Dosators to Deliver Dry Powder Aerosol Drugs to Mice

<ol>
	<li>Wu, X., Li, X., Mansour, H. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Surface+analytical+techniques+in+solid-state+particle+characterization+for+predicting+performance+in+dry+powder+inhalers.">Surface analytical techniques in solid-state particle characterization for predicting performance in dry powder inhalers.</a> KONA Powder and Particle Journal. 28, 3-18 (2010).</li><li>Maloney, S. E., Mecham, J. B., Hickey, A. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Performance+testing+for+dry+powder+inhaler+products:+towards+clinical+relevance.">Performance testing for dry powder inhaler products: towards clinical relevance.</a> KONA Powder and Particle Journal. 40, 172-185 (2023).</li><li>Maloney, S. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spray+dried+tigecycline+dry+powder+aerosols+for+the+treatment+of+nontuberculous+mycobacterial+pulmonary+infections.">Spray dried tigecycline dry powder aerosols for the treatment of nontuberculous mycobacterial pulmonary infections.</a> Tuberculosis. 139, 102306 (2023).</li><li>Kaur, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+hand-held+apparatus+for+&amp;#34;nose-only&amp;#34;+exposure+of+mice+to+inhalable+microparticles+as+a+dry+powder+inhalation+targeting+lung+and+airway+macrophages.">A hand-held apparatus for &amp;#34;nose-only&amp;#34; exposure of mice to inhalable microparticles as a dry powder inhalation targeting lung and airway macrophages.</a> European Journal of Pharmaceutical Sciences. 34 (1), 56-65 (2008).</li><li>Yi, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Whole-body+nanoparticle+aerosol+inhalation+exposures.">Whole-body nanoparticle aerosol inhalation exposures.</a> Journal of Visualized Experiments. (75), e50263 (2013).</li><li>Chung, Y. H., Han, J. H., Lee, Y. -. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+study+on+subchronic+inhalation+toxicology+of+1-chloropropane.">A study on subchronic inhalation toxicology of 1-chloropropane.</a> Toxicological Research. 31 (4), 393-402 (2015).</li><li>Kuehl, P. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regional+particle+size+dependent+deposition+of+inhaled+aerosols+in+rats+and+mice.">Regional particle size dependent deposition of inhaled aerosols in rats and mice.</a> Inhalation Toxicology. 24 (1), 27-35 (2012).</li><li>Manser, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Design+considerations+for+intratracheal+delivery+devices+to+achieve+proof-of-concept+dry+powder+biopharmaceutical+delivery+in+mice.">Design considerations for intratracheal delivery devices to achieve proof-of-concept dry powder biopharmaceutical delivery in mice.</a> Pharmaceutical Research. 40, 1165-1176 (2023).</li><li>Stewart, I. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+and+characterization+of+a+dry+powder+formulation+for+anti-tuberculosis+drug+spectinamide+1599.">Development and characterization of a dry powder formulation for anti-tuberculosis drug spectinamide 1599.</a> Pharmaceutical Research. 36 (9), 136 (2019).</li><li>Durham, P. G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Disposable+dosators+for+pulmonary+insufflation+of+therapeutic+agents+to+small+animals.">Disposable dosators for pulmonary insufflation of therapeutic agents to small animals.</a> Journal of Visualized Experiments. (121), e55356 (2017).</li><li>Miwata, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intratracheal+administration+of+siRNA+dry+powder+targeting+vascular+endothelial+growth+factor+inhibits+lung+tumor+growth+in+mice.">Intratracheal administration of siRNA dry powder targeting vascular endothelial growth factor inhibits lung tumor growth in mice.</a> Molecular Therapy: Nucleic Acids. 12, 698-706 (2018).</li><li>Duret, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pharmacokinetic+evaulation+in+mice+of+amorphous+itraconazole-based+dry+powder+formulations+for+inhalation+with+high+bioavailability+and+extended+lung+retention.">Pharmacokinetic evaulation in mice of amorphous itraconazole-based dry powder formulations for inhalation with high bioavailability and extended lung retention.</a> European Journal of Pharmaceutics and Biopharmaceutics. 86 (1), 46-54 (2014).</li><li>Maloney, S. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preparation+strategies+of+the+anti-mycobacterial+drug+bedaquiline+for+intrapulmonary+routes+of+administration.">Preparation strategies of the anti-mycobacterial drug bedaquiline for intrapulmonary routes of administration.</a> Pharmaceuticals. 16 (5), 729 (2023).</li><li>Price, D. N., Kunda, N. K., Muttil, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Challenges+associated+with+the+pulmonary+delivery+of+therapeutic+dry+powders+for+preclinical+testing.">Challenges associated with the pulmonary delivery of therapeutic dry powders for preclinical testing.</a> KONA Powder and Particle Journal. 36, 129-144 (2019).</li><li>Qiu, Y., Liao, Q., Chow, M. Y. T., Lam, J. K. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intratracheal+administration+of+dry+powder+formulation+in+mice.">Intratracheal administration of dry powder formulation in mice.</a> Journal of Visualized Experiments. (161), e61469 (2020).</li><li>Fiegel, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preparation+and+in+vivo+evaluation+of+a+dry+powder+for+inhalation+of+capreomycin.">Preparation and in vivo evaluation of a dry powder for inhalation of capreomycin.</a> Pharmaceutical Research. 25 (4), 805-811 (2008).</li></ol>

As mice are obligate nose breathers, delivery via passive inhalation for initial proof-of-concept studies makes efficiency and dose estimation challenging as the powder must pass the nose and throat in a manner dependent on particle properties and powder dispersion efficiency7,8,14. The use of the dosators developed herein bypasses the nose and throat, with the dosator inserted to the first bronchial bifurcation<sup cla...

The use of dry powder inhalers (DPIs) for pulmonary drug delivery has garnered significant interest over the past three decades due to the global phase-out of chlorofluorocarbon propellants1,2. DPIs offer numerous benefits over other pulmonary delivery systems, such as metered dose inhalers and nebulizers, including formulation stability, portability, ease of use, and propellant-free dispersal mechanisms2. However, before moving DPI products toward clinical translation, several preclinical studies must be conducted, many of which are initially completed using a murine model. Nevertheless, technologies available to deliver dry powders accurately and reproducibly to small animals are limited.
Common methods to deliver dry powders to small animals, such as mice, include passive inhalation3,4,5,6,7 and direct administration8,9,10,11,12,13. Passive inhalation typically requires a custom chamber that utilizes large doses of spray-dried powder to prepare a sufficient aerosol cloud. As mice are obligate nose breathers14, delivery by passive inhalation requires the powder to travel through the nose and throat to reach the lungs, necessitating the maintenance of an aerosol cloud with sufficient particle aerodynamic properties7,8. While a useful technique that is more physiologically relevant than direct delivery due to inhalation as a result of normal breathing14, it may not be suitable for initial studies where powder mass is limited.
Alternatively, a number of intratracheal delivery devices for direct dry powder delivery have been reported8,9,10,11,12,13. Intratracheal devices bypass the nose and throat, delivering the powder directly to the lungs and allowing for finer control over the delivered dose14. Additionally, some devices, especially those prepared using a tamping loading procedure9, can be prepared with smaller quantities, which is an important consideration for initial proof-of-concept studies. The lack of universally available intratracheal delivery devices has hindered their potential for use, limiting availability and leading to interlaboratory differences14. In this study, we propose a simple, inexpensive, disposable dosator for intratracheal delivery that can be utilized for proof-of-concept murine studies in the development of dry powder aerosols.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>0.6 mL microcentrifuge tubes</td>
			<td>Fisher Scientific</td>
			<td>05-408-120</td>
			<td></td>
		</tr>
		<tr>
			<td>Analytical balance</td>
			<td>Mettler Toledo</td>
			<td>AR1140</td>
			<td>Any analytical balance with sufficient range can be used</td>
		</tr>
		<tr>
			<td>Blunt stainless-steel needle, 1 inch, 21 G</td>
			<td>McMaster-Carr</td>
			<td>75165A681</td>
			<td></td>
		</tr>
		<tr>
			<td>Blunt stainless-steel needle, 1 inch, 22 G</td>
			<td>McMaster-Carr</td>
			<td>75165A683</td>
			<td></td>
		</tr>
		<tr>
			<td>Blunt stainless-steel needle, 1 inch, 25 G</td>
			<td>McMaster-Carr</td>
			<td>75165A687</td>
			<td></td>
		</tr>
		<tr>
			<td>Disposable syringe with luer lock (1 mL)</td>
			<td>Fisher Scientific</td>
			<td>14-823-30</td>
			<td>3-mL syringes can also be used</td>
		</tr>
		<tr>
			<td>Female BALB/c mice&#160;</td>
			<td>Charles River, Wilmington, MA, USA</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>High-performance cascade impactor&#160;</td>
			<td>Next Generation Impactor</td>
			<td>Apparatus 5</td>
			<td></td>
		</tr>
		<tr>
			<td>Lab film (e.g., Parafilm)</td>
			<td>Fisher Scientific</td>
			<td>S37440</td>
			<td></td>
		</tr>
		<tr>
			<td>Low-lint wiper (e.g., Kimwipes)</td>
			<td>Kimberly-Clark Professional</td>
			<td>34133</td>
			<td></td>
		</tr>
		<tr>
			<td>Low-resistance dry powder inhaler&#160;</td>
			<td>RS01 mod 7</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Polypropylene needle, 1.5 inch, 16 G</td>
			<td>McMaster-Carr</td>
			<td>6934A111</td>
			<td></td>
		</tr>
		<tr>
			<td>Polypropylene needle, 1.5 inch, 18 G</td>
			<td>McMaster-Carr</td>
			<td>6934A53</td>
			<td></td>
		</tr>
		<tr>
			<td>Polypropylene needle, 1.5 inch, 20 G</td>
			<td>McMaster-Carr</td>
			<td>6934A55</td>
			<td></td>
		</tr>
		<tr>
			<td>Precision sectioning saw</td>
			<td>TedPella</td>
			<td>812-300</td>
			<td>Belt sander can be used as an alternative</td>
		</tr>
		<tr>
			<td>PTFE needle, 2 inch, 20 G</td>
			<td>McMaster-Carr</td>
			<td>75175A694</td>
			<td></td>
		</tr>
		<tr>
			<td>USP General Chapter &#60;601&#62;&#160;</td>
			<td></td>
			<td></td>
			<td>http://www.uspbpep.com/usp31/v31261/usp31nf26s1_c601.asp</td>
		</tr>
	</tbody>
</table>

disposable dosators intended for dry powder delivery to mice

Dry powder inhalers offer numerous advantages for delivering drugs to the lungs, including stable solid-state drug formulations, device portability, bolus metering and dosing, and a propellant-free dispersal mechanism. To develop pharmaceutical dry powder aerosol products, robust in vivo testing is essential. Typically, initial studies involve using a murine model for preliminary evaluation before conducting formal studies in larger animal species. However, a significant limitation in this approach is the lack of suitable device technology to accurately and reproducibly deliver dry powders to small animals, hindering such models&#39; utility. To address these challenges, disposable syringe dosators were developed specifically for intrapulmonary delivery of dry powders in doses appropriate for mice. These dosators load and deliver a predetermined amount of powder obtained from a uniform bulk density powder bed. This discrete control is achieved by inserting a blunt needle to a fixed depth (tamping) into the powder bed, removing a fixed quantity each time. Notably, this dosing pattern has proven effective for a range of spray-dried powders. In experiments involving four different model spray-dried powders, the dosators demonstrated the ability to achieve doses within the range of 30 to 1100 &#181;g. The achieved dose was influenced by factors such as the number of tamps, the size of the dosator needle, and the specific formulation used. One of the key benefits of these dosators is their ease of manufacturing, making them accessible and cost-effective for delivering dry powders to mice during initial proof-of-concept studies. The disposable nature of the dosators facilitates use in animal procedure rooms, where cleaning and refilling reusable systems and weighing materials is inconvenient. Thus, developing disposable syringe dosators has addressed a significant hurdle in murine dry powder delivery for proof-of-concept studies, enabling researchers to conduct more accurate and reproducible preliminary studies in small animal models for pulmonary drug delivery.

Author Spotlight: Developing a Disposable Dosator for Preclinical Testing of Dry Powder Inhalers in Small Animal Models 

Disposable Dosators Intended for Dry Powder Delivery to Mice

The aerosol performance&#160;of various spray-dried powders was established prior to use in this study. The aerodynamic particle size distribution (APSD) was described by the mass median aerodynamic diameter (MMAD), representing the size that divides the distribution in two at the 50th percentile (d50), and the geometric standard deviation (GSD), reflecting the breadth of the distribution. The GSD is defined by the square root of the aerodynamic diameter at the 80th percentile divided by ...

Watch this Scientific Journal Video about Developing a Disposable Dosator for Preclinical Testing of Dry Powder Inhalers in Small Animal Models at JoVE.com

Pharmaceutical dry powder development necessitates reliable in vivo testing, often using a murine model. Device technology for accurately and reproducibly delivering dry powder aerosols to mice is restricted. This study presents disposable dosators for pulmonary drug delivery at mouse-relevant doses, aiding initial proof-of-concept research.

Dry powder inhalers offer numerous advantages for delivering drugs to the lungs, including stable solid-state drug formulations, device portability, bolus ...

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606 ビュー.  RTI International. 抗酸菌性疾患の吸入療法のための新規および既存の薬を開発しています。私たちは、薬剤耐性菌を治療するための新しいアプローチに焦点を当てており、乾燥粉末を使用して安全性と有効性を確保しています。乾燥粉末吸入器製品の初期前臨床試験は、通常、より大きな動物モデルに移行する前にマウスモデルで行われます。このアプローチの大きな制限は、乾燥?...

ビデオ: Author Spotlight: Developing a Disposable Dosator for Preclinical Testing of Dry Powder Inhalers in Small Animal Models 

Pharmaceutical dry powder development necessitates reliable in vivo testing, often using a murine model. Device technology for accurately and reproducibly delivering dry powder aerosols to mice is restricted. This study presents disposable dosators for pulmonary drug delivery at mouse-relevant doses, aiding initial proof-of-concept...

https://cloudfront.jove.com/CDNSource/teasers/65756_b.jpg

assembling and actuating a disposable dosator for dry powder drug delivery

Assembling and Actuating a Disposable Dosator for Dry Powder Drug Delivery  

a rat dry eye model with lacrimal gland dysfunction induced by scopolamine

Author Spotlight: Challenges in Developing Dry Eye Animal Models and Future Research Directions

Here, we establish a rat model of lacrimal gland dysfunction to provide a basis for the study of aqueous-deficient dry...

Scopolamine-Induced Lacrimal Gland Dysfunction in Rats

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intratracheal administration of dry powder formulation in mice

Intratracheal Administration of Dry Powder Formulation in Mice

Dry powder formulations for inhalation have great potential in treating respiratory diseases. Before entering human studies, it is necessary to evaluate the efficacy of the dry powder formulation in preclinical studies. A simple and noninvasive method of the administration of dry powder in mice through the intratracheal route is...

disposable dosators for pulmonary insufflation of therapeutic agents to small animals

Disposable Dosators for Pulmonary Insufflation of Therapeutic Agents to Small Animals

During development of drugs for pulmonary delivery, it is necessary to evaluate pharmacokinetics and efficacy in an animal model. We present a method to build a disposable aerosol dispersion system from of-the-shelf components that can be used to administer intrapulmonary dry powder aerosol to...

subconjunctival administration of adeno-associated virus vectors in small animal models

Subconjunctival Administration of Adeno-associated Virus Vectors in Small Animal Models

In this manuscript, subconjunctival injection is demonstrated as a valid vector delivery method for ocular tissues in mice using an injection system consisting of an infusion/withdrawal syringe pump and a gastight removable syringe coupled with microinjection needles. This injection system is also adaptable for other intraocular administration routes.

rodent model of masseter volumetric muscle loss for studying bioengineering materials

Author Spotlight: Developing Experimental Models for Volumetric Muscle Loss

Here, we describe a protocol for the surgical creation of a volumetric muscle loss (VML) injury in the rat masseter, providing a reproducible and accessible model for the study of craniofacial muscle injuries and their treatment using biomaterials such as the novel...

Evaluating Biomaterials in Craniofacial VML Injury Using a Rat Model

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production of adeno-associated virus vectors in cell stacks for preclinical studies in large animal models

Production of Adeno-Associated Virus Vectors in Cell Stacks for Preclinical Studies in Large Animal Models

Here we provide a detailed procedure for large-scale production of research-grade AAV vectors using adherent HEK 293 cells grown in cell stacks and affinity chromatography purification. This protocol consistently yields &#62;1 x 1013 vector genomes/mL, providing vector quantities appropriate for large animal...

a real-time wearable electromyography measurement system for small animals

Author Spotlight: Development of a Wireless Wearable EMG System with Closed-Loop Feedback for Small Animal Muscle and Nerve Stimulation

A protocol is presented for the installation and preparation of intramuscular electrodes, along with an animal-mountable, miniaturized measurement device for electromyography (EMG) analysis in locomotion studies. This system enables the wireless transmission of real-time EMG data for investigating locomotion recovery in stroke model...

Wireless Intramuscular EMG System for Locomotion Studies in Stroke Model Rats

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barnes maze testing strategies with small and large rodent models

Barnes Maze Testing Strategies with Small and Large Rodent Models

The dry-land Barnes maze is widely used to measure spatial navigation ability in response to mildly aversive stimuli. Over consecutive days, performance (e.g.&#160;latency to locate escape cage) of control subjects improves, indicative of normal learning and memory. Differences between rats and mice necessitate apparatus and methodology changes that are detailed...

dry powder and nebulized aerosol inhalation of pharmaceuticals delivered to mice using a nose-only exposure system

Dry Powder and Nebulized Aerosol Inhalation of Pharmaceuticals Delivered to Mice Using a Nose-only Exposure System

The inhalation unit described herein can generate, sample for characterization, and uniformly deposit a drug aerosol in the lungs of rodents. This enables the pre-clinical determination of the efficacy and safety of drug doses deposited in the lungs; key data enabling clinical inhaled drug...

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Author Spotlight: Enhancing Small Animal Bone Compression Testing for Research

In this protocol, two approaches are described to make uniaxial compression testing of mouse lumbar vertebrae more attainable. First, the conversion of a three-point bending machine to a compression testing machine is described. Second, an embedding method for preparing the loading surface that uses bone cement is adapted for mouse lumbar...

Compression Testing of Mouse Vertebra for Determination of Mechanical Strength

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endotracheal intubation via tracheotomy and subsequent thoracotomy in rats for non-survival applications

Author Spotlight: Hyperspectral Imaging for Spectral Analysis of Thoracic Organs in Clinical and Animal Models

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Tracheotomy-Based Endotracheal Intubation Protocol for Non-Survival Rat Models

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a high-performance compact photoacoustic tomography system for in vivo small-animal brain imaging

A High-performance Compact Photoacoustic Tomography System for In Vivo Small-animal Brain Imaging

A compact pulsed-laser diode-based photoacoustic tomography (PLD-PAT) system for high-speed in vivo brain imaging in small animals is...

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A Small Animal Model of Ex Vivo Normothermic Liver Perfusion

There is a significant liver donor shortage, and criteria for liver donors have been expanded. Normothermic ex vivo liver perfusion (NEVLP) has been developed to evaluate and modify organ function. This study demonstrates a rat model of NEVLP and tests the ability of pegylated-catalase, to mitigate liver preservation...

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A Micro-CT-based Method for Characterizing Lesions and Locating Electrodes in Small Animal Brains

This article describes a straightforward method to prepare small animal brains for micro-CT imaging, in which lesions can be quantified and electrodes located with high precision in the context of the whole...

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Dural Stimulation and Periorbital von Frey Testing in Mice As a Preclinical Model of Headache

The most notable symptom of migraine is severe head pain, and it is hypothesized that this is mediated by sensory neurons innervating the meninges. Here, we present a method to locally apply substances to the dura in a minimally invasive manner while using facial hypersensitivity as an output.

To prepare the disposable dosator and its filling components, take a 2.5 centimeter or 1 inch blunt stainless steel needle of 21 to 25 gauge. Utilizing a precision sectioning saw or a belt sander, trim the plastic lure part of the needle, leaving about 2 to 3 millimeters of the plastic lure attached to the needle. Next, cut off approximately 1 to 1.5 centimeters from the tip of a 0.6 milliliter conical centrifuge tube.After that, fill this cut tip with 30 to 35 milligrams of the powder of interest. For storing or transporting the powder, place the cutoff tube cap onto the cut tip containing the powder. Use paraffin film to wrap the cover, minimizing the powder's exposure to ambient moisture.To load the dosator, tamp the trimmed stainless steel needle into the powder bed in the cut tip as many times as required to achieve the desired dose. Using a low lint wiper, gently wipe the sides of the needle to remove any excess powder. Then take a 3.81 centimeter or 1.5 inch polypropylene needle of 16 to 20 gauge and cautiously insert the loaded stainless steel needle into it, making sure not to dislodge any powder.Alternatively, use a 5.08 centimeter or 2 inch PTFE needle for the same. To actuate the dosator, first draw back a disposable syringe to the desired volume based on the application. Then attach the syringe to the lure lock on the polypropylene or PTFE needle before inserting the needle end of the dosator into the desired target.To analyze powder content and reproducibility, insert the dosator needle through a perforated rubber septum or paraffin film into a vial with a small quantity of liquid. Forcefully depress the syringe plunger, expelling the powder from the device into the collection vial. Finally, analyze the powder solution in the vial using UV's visible spectra photometry to monitor the dose of the powder released from the dosator.Four different spray dried powders visualized using scanning electron microscopy were considered for delivery using the demonstrated dosator. The delivered dose as a function of the number of Tamps in the powder bed, was obtained from UV visible spectra photometry of the powder solutions. Notably, all spray dried powders demonstrated a linear dose response from 1 to 4 Tamps.The first Tamp always incurred a larger dose of powder than subsequent Tamps. When compared to the demonstrated 21 gauge stainless steel with a 16 gauge polypropylene dosator, a slight increase in achievable dose was observed using a 21 gauge stainless steel with a 20 gauge PTFE dosator for powder SD 1. As expected, the achievable dose of SD 1 decreased for a 22 gauge stainless steel with an 18 gauge polypropylene dosator, having a smaller inner needle diameter.A 25 gauge stainless steel with a 20 gauge polypropylene dosator further decreased the initial and subsequent Tamp doses. This is a comparison of the four dosator systems that were evaluated, highlighting that the dosators can be customized to meet different dosage needs.