1
|
Hebbink GA, Jaspers M, Peters HJW, Dickhoff BHJ. Recent developments in lactose blend formulations for carrier-based dry powder inhalation. Adv Drug Deliv Rev 2022; 189:114527. [PMID: 36070848 DOI: 10.1016/j.addr.2022.114527] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 08/24/2022] [Accepted: 08/30/2022] [Indexed: 01/24/2023]
Abstract
Lactose is the most commonly used excipient in carrier-based dry powder inhalation (DPI) formulations. Numerous inhalation therapies have been developed using lactose as a carrier material. Several theories have described the role of carriers in DPI formulations. Although these theories are valuable, each DPI formulation is unique and are not described by any single theory. For each new formulation, a specific development trajectory is required, and the versatility of lactose can be exploited to optimize each formulation. In this review, recent developments in lactose-based DPI formulations are discussed. The effects of varying the material properties of lactose carrier particles, such as particle size, shape, and morphology are reviewed. Owing to the complex interactions between the particles in a formulation, processing adhesive mixtures of lactose with the active ingredient is crucial. Therefore, blending and filling processes for DPI formulations are also reviewed. While the role of ternary agents, such as magnesium stearate, has increased, lactose remains the excipient of choice in carrier-based DPI formulations. Therefore, new developments in lactose-based DPI formulations are crucial in the optimization of inhalable medicine performance.
Collapse
|
2
|
Rudén J, Frenning G, Bramer T, Thalberg K, An J, Alderborn G. Linking carrier morphology to the powder mechanics of adhesive mixtures for dry powder inhalers via a blend-state model. Int J Pharm 2019; 561:148-160. [PMID: 30825556 DOI: 10.1016/j.ijpharm.2019.02.038] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 02/04/2019] [Accepted: 02/23/2019] [Indexed: 11/17/2022]
Abstract
The aim of this study was to investigate how the carrier morphology affects the expression of blend states in adhesive mixtures as a function of surface coverage ratio (SCR) and to identify where transitions between the different states occur. Adhesive mixtures of five lactose carriers with varying contents of lactose fines, corresponding to blends with different SCR ranging from 0 to 6, were produced by low-shear mixing. The powder mechanics of the mixtures were characterized by bulk density, compressibility and permeability. The appearance of the carriers and blends was studied by scanning electron microscopy, light microscopy and atomic force microscopy. The size and morphology of the carriers had a crucial impact on the evolution of the blend state, and affected the powder mechanical properties of the mixtures. It was found that smaller carriers with little or no surface irregularities were more sensitive to additions of fines resulting in self-agglomeration of fines at relatively low SCR values. On the contrary, carriers with irregular surface structures and larger sizes were able to reach higher SCR values before self-agglomeration of fines occurred. This could be attributed to an increased deagglomeration efficiency of irregular and larger carriers and to fines predominantly adhering to open pores.
Collapse
Affiliation(s)
- Jonas Rudén
- Department of Pharmacy and the Swedish Drug Delivery Forum (SDDF), Uppsala University, Husargatan 3, Box 580, SE-751 23 Uppsala, Sweden.
| | - Göran Frenning
- Department of Pharmacy and the Swedish Drug Delivery Forum (SDDF), Uppsala University, Husargatan 3, Box 580, SE-751 23 Uppsala, Sweden
| | - Tobias Bramer
- Pharmaceutical Sciences, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Kyrre Thalberg
- Inhalation Product Development, Pharmaceutical Technology & Development, AstraZeneca, Gothenburg, Sweden
| | - Junxue An
- Department of Pharmacy and the Swedish Drug Delivery Forum (SDDF), Uppsala University, Husargatan 3, Box 580, SE-751 23 Uppsala, Sweden
| | - Göran Alderborn
- Department of Pharmacy and the Swedish Drug Delivery Forum (SDDF), Uppsala University, Husargatan 3, Box 580, SE-751 23 Uppsala, Sweden
| |
Collapse
|
3
|
Rudén J, Frenning G, Bramer T, Thalberg K, Alderborn G. Relationships between surface coverage ratio and powder mechanics of binary adhesive mixtures for dry powder inhalers. Int J Pharm 2018; 541:143-156. [PMID: 29454905 DOI: 10.1016/j.ijpharm.2018.02.017] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Revised: 02/14/2018] [Accepted: 02/14/2018] [Indexed: 10/18/2022]
Abstract
The aim of this paper was to study relationships between the content of fine particles and the powder mechanics of binary adhesive mixtures and link these relationships to the blend state. Mixtures with increasing amounts of fine particles (increasing surface coverage ratios (SCR)) were prepared using Lactopress SD as carrier and micro particles of lactose as fines (2.7 µm). Indicators of unsettled bulk density, compressibility and flowability were derived and the blend state was visually examined by imaging. The powder properties studied showed relationships to the SCR characterised by stages. At low SCR, the fine particles predominantly gathered in cavities of the carriers, giving increased bulk density and unchanged or improved flow. Thereafter, increased SCR gave a deposition of particles at the enveloped carrier surface with a gradually more irregular adhesion layer leading to a reduced bulk density and a step-wise reduced flowability. The mechanics of the mixtures at a certain stage were dependent on the structure and the dynamics of the adhesion layer and transitions between the stages were controlled by the evolution of the adhesion layer. It is advisable to use techniques based on different types of flow in order to comprehensively study the mechanics of adhesive mixtures.
Collapse
Affiliation(s)
- Jonas Rudén
- Department of Pharmacy, Uppsala University, Husargatan 3, Box 580, SE-751 23 Uppsala, Sweden.
| | - Göran Frenning
- Department of Pharmacy, Uppsala University, Husargatan 3, Box 580, SE-751 23 Uppsala, Sweden
| | - Tobias Bramer
- Pharmaceutical Sciences, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Kyrre Thalberg
- Inhalation Product Development, Pharmaceutical Technology & Development, AstraZeneca, Gothenburg, Sweden
| | - Göran Alderborn
- Department of Pharmacy, Uppsala University, Husargatan 3, Box 580, SE-751 23 Uppsala, Sweden
| |
Collapse
|
4
|
Kaialy W. On the effects of blending, physicochemical properties, and their interactions on the performance of carrier-based dry powders for inhalation - A review. Adv Colloid Interface Sci 2016; 235:70-89. [PMID: 27291646 DOI: 10.1016/j.cis.2016.05.014] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Revised: 05/04/2016] [Accepted: 05/28/2016] [Indexed: 11/25/2022]
Abstract
Blending drug and carrier powders to produce homogeneous drug-carrier adhesive mixtures is a key step in the production of dry powder inhaler (DPI) formulations. Although the blending conditions can result in different conclusions or probably change the outcome of a study entirely if being selected differently, there is a scarcity of data on the influence of blending processes on the physicochemical properties of bulk powder formulations and the follow-on effects on DPI performance. This paper provides an overview of the interactions between variables related to blending conditions (e.g. blending equipment, time, speed and sequence as well as environmental humidity) and powder physicochemical properties (e.g. size distribution, shape distribution, density, anomeric composition, electrostatic charge, surface, and bulk properties), and their effects on the performance of adhesive mixtures for inhalation in terms of drug content homogeneity, drug-carrier adhesion, and drug aerosolisation behaviour. The relevance of carrier payload, batch size and segregation was also discussed. Challenges and future directions were identified. This review therefore contributes towards a better understanding of the blending process, powder physicochemical properties, and their interlinked effects on the fundamental understanding of adhesive mixtures for inhalation. The knowledge gained is essential to ensure optimum blending and thereby controlled functionality of DPIs.
Collapse
|
5
|
Singh DJ, Jain RR, Soni PS, Abdul S, Darshana H, Gaikwad RV, Menon MD. Preparation and Evaluation of Surface Modified Lactose Particles for Improved Performance of Fluticasone Propionate Dry Powder Inhaler. J Aerosol Med Pulm Drug Deliv 2014; 28:254-67. [PMID: 25517187 DOI: 10.1089/jamp.2014.1146] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Dry powder inhalers (DPI) are generally formulated by mixing micronized drug particles with coarse lactose carrier particles to assist powder handling during the manufacturing and powder aerosol delivery during patient use. METHODS In the present study, surface modified lactose (SML) particles were produced using force control agents, and their in vitro performance on dry powder inhaler (DPI) formulation of Fluticasone propionate was studied. With a view to reduce surface passivation of high surface free energy sites on the most commonly used DPI carrier, α- lactose monohydrate, effects of various force control agents such as Pluronic F-68, Cremophor RH 40, glyceryl monostearate, polyethylene glycol 6000, magnesium stearate, and soya lecithin were studied. RESULTS DPI formulations prepared with SML showed improved flow properties, and atomic force microscopy (AFM) studies revealed decrease in surface roughness. The DSC and X-ray diffraction patterns of SML showed no change in the crystal structure and thermal behavior under the experimental conditions. The fine particle fraction (FPF) values of lactose modified with Pluronic F-68, Cremophor RH 40, glyceryl monostearate were improved, with increase in concentration up to 0.5%. Soya lecithin and PEG 6000 modified lactose showed decrease in FPF value with increase in concentration. Increase in FPF value was observed with increasing concentration of magnesium stearate. Two different DPI devices, Rotahaler(®) and Diskhaler(®), were compared to evaluate the performance of SML formulations. FPF value of all SML formulations were higher using both devices as compared to the same formulations prepared using untreated lactose. One month stability of SML formulations at 40°C/75% RH, in permeable polystyrene tubes did not reveal any significant changes in FPF values. CONCLUSION SML particles can help in reducing product development hindrances and improve inhalational properties of DPI.
Collapse
Affiliation(s)
- Deepak J Singh
- 1 Department of Pharmaceutics, Bombay College of Pharmacy , Mumbai, India
| | - Rajesh R Jain
- 1 Department of Pharmaceutics, Bombay College of Pharmacy , Mumbai, India
| | - P S Soni
- 2 Board of Radiation and Isotope Technology and Medical Cyclotron Facility , Parel, Mumbai, India
| | - Samad Abdul
- 3 Department of Medicine, Bombay Veterinary College , Parel, Mumbai, India
| | - Hegde Darshana
- 1 Department of Pharmaceutics, Bombay College of Pharmacy , Mumbai, India
| | - Rajiv V Gaikwad
- 3 Department of Medicine, Bombay Veterinary College , Parel, Mumbai, India
| | - Mala D Menon
- 1 Department of Pharmaceutics, Bombay College of Pharmacy , Mumbai, India
| |
Collapse
|
6
|
Kaialy W, Nokhodchi A. Engineered mannitol ternary additives improve dispersion of lactose-salbutamol sulphate dry powder inhalations. AAPS JOURNAL 2013; 15:728-43. [PMID: 23591748 DOI: 10.1208/s12248-013-9476-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Accepted: 03/18/2013] [Indexed: 12/18/2022]
Abstract
The aim of this study was to evaluate the influence of novel engineered fine mannitol particles (4.7%, w/w) on the performance of lactose-salbutamol sulphate dry powder inhaler (DPI) formulations to obtain promising aerosolisation properties. The results showed that the more elongated the fine mannitol particles, the weaker the drug-carrier adhesion, the better the drug content homogeneity, the higher the amount of drug expected to be delivered to the lower airways and the higher the total DPI formulation desirability. Linear relationships were established showing that mannitol particles with a more elongated shape generated powders with broader size distributions and that were less uniform in shape. The weaker the drug-carrier adhesion, the higher the fine particle fraction of the drug is upon aerosolisation. It is believed that more elongated fine mannitol particles reduce the number of drug-carrier and drug-drug physical contact points and increase the ability of the drug particles to travel into the lower airways. Additionally, a lower drug-carrier contact area, lower drug-carrier press-on forces and easier drug-carrier detachment are suggested in the case of formulations containing more elongated fine mannitol particles. Ternary 'drug-coarse carrier-elongated fine ternary component' DPI formulations were more favourable than both 'drug-coarse carrier' and 'drug-elongated coarse carrier' binary formulations. This study provides a comprehensive approach for formulators to overcome the undesirable properties of dry powder inhalers, as both improved aerosolisation performance and reasonable flow characteristics were obtained using only a small amount of elongated engineered fine mannitol particles.
Collapse
Affiliation(s)
- Waseem Kaialy
- Chemistry and Drug Delivery Group, Medway School of Pharmacy, University of Kent, ME4 4TB, Kent, UK.
| | | |
Collapse
|
7
|
Salama RO, Young PM, Rogueda P, Lallement A, Iliev I, Traini D. Advances in drug delivery: is triple therapy the future for the treatment of chronic obstructive pulmonary disease? Expert Opin Pharmacother 2011; 12:1913-32. [DOI: 10.1517/14656566.2011.589837] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
8
|
Behara SRB, Kippax P, McIntosh MP, Morton DAV, Larson I, Stewart P. Structural influence of cohesive mixtures of salbutamol sulphate and lactose on aerosolisation and de-agglomeration behaviour under dynamic conditions. Eur J Pharm Sci 2010; 42:210-9. [PMID: 21112390 DOI: 10.1016/j.ejps.2010.11.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2010] [Revised: 11/11/2010] [Accepted: 11/19/2010] [Indexed: 11/24/2022]
Abstract
PURPOSE The purpose of this study was to understand the behaviour of cohesive powder mixtures of salbutamol sulphate (SS) and micronized lactose (LH300) at ratios of SS:LH300 of 1:1, 1:2, 1:4 and 1:8 under varying air flow conditions. METHODS Aerosolisation of particles less than 5.4μm at air flow rates from 30 to 180 l min(-1) was investigated by determining particle size distributions of the aerosolised particles using laser diffraction and fine particle fractions of SS using the twin stage impinger modified for different air flow rates using a Rotahaler(®). The de-agglomeration data were best fitted by a 3-parameter sigmoidal equation using non-linear least squares regression and characterised by the estimated parameters. RESULTS De-agglomeration air flow rate profiles showed that SS:LH300 mixtures with increased lactose content (1:4 and 1:8) improved powder aerosolisation, but lactose had negligible effect on SS aerosolisation at the higher and lower limits of air flow rates studied. De-agglomeration flow rate profiles of SS-LH300 mixtures with increased lactose content (1:4 and 1:8) were greater than theoretically expected based on weighted individual SS and LH300 profiles. This indicated that interactions between the cohesive components led to enhanced de-agglomeration. The composition of the aerosol plume changed with air flow rate. CONCLUSION This approach to characterising aerosolisation behaviour has significant applications in understanding powder structures and in formulation design for optimal aerosolisation properties.
Collapse
Affiliation(s)
- Srinivas Ravindra Babu Behara
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia
| | | | | | | | | | | |
Collapse
|
9
|
Begat P, Morton DA, Shur J, Kippax P, Staniforth JN, Price R. The Role of Force Control Agents in High-Dose Dry Powder Inhaler Formulations. J Pharm Sci 2009; 98:2770-83. [DOI: 10.1002/jps.21629] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
10
|
Padhi BK, Chougule MB, Misra A. Optimization of Formulation Components and Characterization of Large Respirable Powders Containing High Therapeutic Payload. Pharm Dev Technol 2008; 11:465-75. [PMID: 17101517 DOI: 10.1080/10837450600939099] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The aim of the study was to optimize and characterize high therapeutic payload large respirable powders prepared by spray-drying technique for maximum fine particle fraction with minimum quantities of excipients. Influence of formulation components was optimized by a three-factor, five-level central composite design having different proportions of L-leucine (X1), tobramycin sulfate (X2), and poloxamer-188 (X3) as the independent variables and fine particle fraction as a response variable (Y). Large respirable powders were characterized for particle size, size distribution, moisture, crystallinity, and morphology. In vitro aerosol performance of powders was determined by an eight-stage Andersen cascade impactor using the Rotahaler. Mathematical model elucidated for Y was Y = 56.2068 + 5.7481 X1 - 3.0531 X2 + 0.8468 X3 + 1.1737 X1 X2 - 0.5012 X1 X3 - 0.7412 X2 X3 - 0.7149 X1(2) - 1.9212 X2(2) - 1.6187X3(2). The component of greatest influence on product performance (response variable) was found to be L-leucine. Lack of fit was not significant (p = 0.08), and regression equation predicted response for Y was in reasonably good agreement with experimental values (p = 0.01; R2 = 0.92). The optimal model predicted with a fine particle fraction of 62.8 +/- 2.6% with X1, X2, X3 levels of 20, 45.71, and 5.51 respectively. Large respirable powders with TB load of 45.7% w/w were prepared; they had smooth surface texture, dimpled spherical shape, roundness value close to 1(1.048 +/- 0.032) and were found to possess bulk tap densities of 0.04 g/cc, geometric particle sizes of 6-7 micro m, and emitted dose of 92%. The results of the studies suggest that in vitro aerosol performance was affected significantly by small and deliberate change of specific formulation components and its proportions. It may be concluded that appropriate type and proportion of excipients is necessary to obtain maximum fine particle fraction of large respirable powders containing high therapeutic payloads.
Collapse
Affiliation(s)
- Bijay Kumar Padhi
- Pharmacy Department, Faculty of Technology and Engineering, Kalabhavan, The MS University of Baroda, Vadodara, Gujarat, India
| | | | | |
Collapse
|
11
|
Shekunov BY, Chattopadhyay P, Tong HHY, Chow AHL. Particle size analysis in pharmaceutics: principles, methods and applications. Pharm Res 2006; 24:203-27. [PMID: 17191094 DOI: 10.1007/s11095-006-9146-7] [Citation(s) in RCA: 258] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2006] [Accepted: 08/07/2006] [Indexed: 11/28/2022]
Abstract
Physicochemical and biopharmaceutical properties of drug substances and dosage forms can be highly affected by the particle size, a critical process parameter in pharmaceutical production. The fundamental issue with particle size analysis is the variety of equivalent particle diameters generated by different methods, which is largely ascribable to the particle shape and particle dispersion mechanism involved. Thus, to enable selection of the most appropriate or optimal sizing technique, cross-correlation between different techniques may be required. This review offers an in-depth discussion on particle size analysis pertaining to specific pharmaceutical applications and regulatory aspects, fundamental principles and terminology, instrumentation types, data presentation and interpretation, in-line and process analytical technology. For illustration purposes, special consideration is given to the analysis of aerosols using time-of-flight and cascade impactor measurements, which is supported by a computational analysis conducted for this review.
Collapse
Affiliation(s)
- Boris Y Shekunov
- Ferro Pfanstiehl Laboratories, Pharmaceutical Technologies, Independence, Ohio 44131, USA.
| | | | | | | |
Collapse
|
12
|
Schiavone H, Palakodaty S, Clark A, York P, Tzannis ST. Evaluation of SCF-engineered particle-based lactose blends in passive dry powder inhalers. Int J Pharm 2005; 281:55-66. [PMID: 15288343 DOI: 10.1016/j.ijpharm.2004.05.029] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2004] [Revised: 05/19/2004] [Accepted: 05/20/2004] [Indexed: 10/26/2022]
Abstract
The objective of this study was to assess the performance of SCF-engineered budesonide and albuterol sulfate powder blends in passive dry powder inhalers (DPI) relative to micronized drug blends. A number of lactose grades for inhalation were screened and the appropriate carrier and drug-to-lactose blending ratio were selected based on drug content and emitted dose uniformity. Aerosol performance was characterized by Andersen cascade impaction. Blend formulations of SEDS (solution enhanced dispersion by supercritical fluids) budesonide and albuterol exhibited a significant drug content uniformity (7-9% RSD) improvement over micronized drug blends (16-20% RSD). Further, the SEDS formulations demonstrated higher emitted dose and reduced emitted dose variability (10-12% RSD) compared to micronized powders (21-25% RSD) in the Turbospin, albeit without significant enhancement of the fine particle fraction. In contrast, SEDS powders exhibited increased fine particle fractions over micronized blends in the Clickhaler; improvements were more pronounced with albuterol sulfate. The performance enhancements observed with the SEDS powders are attributed to their increased surface smoothness and reduced surface energy that are presumed to minimize irreversible drug-carrier particle interactions, thus resulting in more efficient drug detachment from the carrier particle surface during aerosolization. As demonstrated for budesonide and albuterol, SEDS may enhance performance of lactose blends and thus provide an attractive particle engineering option for the development of blend formulations for inhalation delivery.
Collapse
Affiliation(s)
- Helena Schiavone
- Drug Delivery R&D, Nektar Therapeutics, 150 Industrial Road, San Carlos, CA 94070, USA
| | | | | | | | | |
Collapse
|
13
|
Chen Y, Ding Y, Papadopoulos DG, Ghadiri M. Energy-based analysis of milling α-lactose monohydrate. J Pharm Sci 2004; 93:886-95. [PMID: 14999726 DOI: 10.1002/jps.10568] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Some observations on the milling of alpha-lactose monohydrate with a Retsch single-ball mill are reported. The effects of mill loading and frequency of the mill motion were investigated. At a given frequency, a lower mill loading showed a higher milling efficiency. For a given mill loading, size reduction rate increased exponentially with frequency. The milling behavior was analyzed with three energy-based models; namely, Rittinger's, Kick's, and Bond's models. The results suggest that Rittinger's model best describes the milling behavior for low mill loadings at high frequencies, whereas the data for high loading milling at low frequencies fit Kick's model better. The results also indicate that attrition and/or chipping is the dominant mechanism for milling at low frequencies with high loadings because of the shear action of the milling ball rolling on the powder bed. Also, as a result of impact of the milling ball on the two ends of the milling jar, fragmentation is responsible for size reduction at high frequencies with low loadings.
Collapse
Affiliation(s)
- Y Chen
- Institute of Particle Science & Engineering, University of Leeds, Leeds LS2 9JT, United Kingdom.
| | | | | | | |
Collapse
|
14
|
Chan LW, Lim LT, Heng PWS. Immobilization of fine particles on lactose carrier by precision coating and its effect on the performance of dry powder formulations. J Pharm Sci 2003; 92:975-84. [PMID: 12712417 DOI: 10.1002/jps.10372] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The feasibility of immobilization of fine particles on a lactose carrier by precision coating and producing carrier particles of different surface roughness from the same core was explored. A relationship between the resultant surface roughness of the carrier and the in vitro deposition pattern of salbutamol sulfate was established. Lactose carrier particles in the precision coating chamber were spray coated with liquid suspensions consisting of micronized lactose dispersed in isopropyl alcohol (IPA) and/or water mixtures. The surface-modified lactose particles were fractionated and then characterized by laser diffraction for size, image analysis for shape, and scanning probe microscopy for surface roughness. The in vitro deposition pattern of salbutamol sulfate from the drug-lactose mixtures was determined with the twin-stage glass impinger and expressed as the fine particle fraction and dispersibility of the drug. Immobilization of fine particles on carrier particles was feasible by the precision coating process as shown by the scanning probe topographs and the roughness values of the carrier particles. Generally, more discrete fine particles were deposited on the carrier surface and a higher surface roughness was seen when the spray suspension consisting of a higher proportion of IPA was used. A significant correlation was found between the fine particle fraction of salbutamol sulfate with the roughness of lactose. This relationship established between the in vitro drug deposition pattern and the microscopic surface roughness of the carrier would be helpful in the optimization of drug delivery to targeted areas in the lungs.
Collapse
Affiliation(s)
- Lai Wah Chan
- Department of Pharmacy, Faculty of Science, National University of Singapore, 18 Science Drive 4, Singapore 117543, Republic of Singapore
| | | | | |
Collapse
|