A review of current techniques for the evaluation of powder mixing

Asachi, Maryam; Nourafkan, Ehsan; Hassanpour, Ali

doi:10.1016/j.apt.2018.03.031

Cited by 82 publications

(36 citation statements)

References 124 publications

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“…For example, in one batch (Batch 1, N = 4 tablets), despite all tablets being very similar in mass (range 256–259 mg), significant variability in content was observed (range 70–184 mg MDMA free‐base). When producing tablets in the pharmaceutical industry, homogeneity of the bulk powder using high‐shear mixing tools is essential to ensure content uniformity of the active pharmaceutical ingredient, and forms an integral part of release‐testing protocols . Variability in MDMA content within a batch of illicit tablets, when the tablet mass is consistent, most likely represents incomplete mixing of the MDMA and tablet excipients prior to pressing and of course demonstrates the inevitable lack of quality control for illicitly produced tablets.…”

Section: Discussionmentioning

confidence: 99%

Variability in content and dissolution profiles of MDMA tablets collected in the UK between 2001 and 2018 – A potential risk to users?

Couchman

Frinculescu

Sobreira

et al. 2019

Drug Testing and Analysis

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3,4‐Methylenedioxymethamphetamine (MDMA, Ecstasy) tablets are widely used recreationally, and not only vary in appearance, but also in MDMA content. Recently, the prevalence of high‐content tablets is of concern to public health authorities. To compare UK data with other countries, we evaluated MDMA content of 412 tablets collected from the UK, 2001–2018, and investigated within‐batch content variability for a sub‐set of these samples. In addition, we investigated dissolution profiles of tablets using pharmaceutical industry‐standard dissolution experiments on 247 tablets. All analyses were carried out using liquid chromatography−tandem mass spectrometry (LC–MS/MS). Our data supported other studies, in that recent samples (2016–2018) tend to have higher MDMA content compared to earlier years. In 2018, the median MDMA content exceeded 100 mg free‐base for the first time. Dramatic within‐batch content variability (up to 136 mg difference) was also demonstrated. Statistical evaluation of dissolution profiles at 15‐minutes allowed tablets to be categorized as fast‐, intermediate‐, or slow‐releasing, but no tablet characteristics correlated with dissolution classification. Hence, there would be no way of users knowing a priori whether a tablet is more likely to be fast or slow‐releasing. Further, within‐batch variation in dissolution rate was observed. Rapid assessment of MDMA content alone provides important data for harm reduction, but does not account for variability in (a) the remainder of tablets in a batch, or (b) MDMA dissolution profiles. Clinical manifestations of MDMA toxicity, especially for high‐content, slow‐releasing tablets, may be delayed or prolonged, and there is a significant risk of users re‐dosing if absorption is delayed.

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Section: Discussionmentioning

confidence: 99%

Variability in content and dissolution profiles of MDMA tablets collected in the UK between 2001 and 2018 – A potential risk to users?

Couchman

Frinculescu

Sobreira

et al. 2019

Drug Testing and Analysis

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“…Powder preparation: Before the cladding process, the metal matrix powder and hard reinforcement powder must be mixed using a suitable mixing process, so that homogeneous properties of the developed clad can be achieved. In the present work, 60% Ni-based alloy EWAC powder and 40% Cr 3 C 2 powder were mixed in V-mechanical mixer blender (LYZER, Ambala Cantt., India; Model: LVB-1) for 12 h (optimized in various studies) 56 , 57 at 30 r/min although the clad powder must be free from moisture content so that defect-free clad can be produced. Further, the mixed powder was placed in a graphite-coated crucible, and the whole setup was preheated in a domestic microwave oven at 180°C for 10 min using convection mode to eliminate the moisture content in the powder.…”

Section: Materials and Methodologymentioning

confidence: 99%

Cavitation erosion behavior of microwave-processed Ni–40Cr₃C₂ composite clads: A parametric investigation using ultrasonic apparatus

Mago

Bansal

Gupta

et al. 2020

Proceedings of the Institution of Mechanical Engineers, Part L:

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Cavitation erosion is the primary cause of material failure of the hydroelectric power plant components. The rapid development in the advanced surface engineering techniques has provided an effective treatment solution for cavitation erosion. One such novel method is microwave cladding. Hence, the Ni–40Cr3C2 composite clad was deposited on austenitic stainless steel (SS-316) using a microwave cladding process in the present study. The processing was carried out in a domestic microwave oven of 2.45 GHz frequency and 900 W power. The developed clad was thoroughly characterized for the metallurgical and mechanical properties related to its behavior as a successful cavitation erosion resistance material, like microstructure, crystal structure, porosity, microhardness, flexural strength, and fracture toughness. The results showed that the stripe-type and agglomerated carbides were present in the Ni–40Cr3C2 clad. The developed composite clad consists of various carbides (SiC, Ni3C, Cr3Ni2SiC, Cr7C3, and NiC) and intermetallic phases (Ni3Fe, Ni2Si, and Cr3Si). Microhardness, flexural strength, and fracture toughness of the microwave-processed clad were observed to be 605 ± 80 HV0.3, 813.23 ± 16.2 MPa, and 7.44 ± 0.2 MPa√m, respectively. The microwave-processed composite clad performance in terms of cavitation erosion resistance was determined using the ultrasonic apparatus (ASTM-G32-17). The cavitation experiments were carried out according to Taguchi L9 orthogonal array, taking into account three parameters: standoff distance, amplitude, and immersion depth. The developed composite clad exhibited significant resistance (mass loss 7.6 times lesser as compared to SS-316) to cavitation erosion. ANOVA results showed the standoff distance as the most important factor followed by amplitude and immersion depth. Least cavitation resistance was observed at a smaller standoff distance, higher amplitude, and lower immersion depth. Linear regression equations were obtained to establish the correlation between parameters and cumulative mass loss. The microwave clad specimens tested at optimized test parameters were damaged in the form of fractured intermetallic, extruded lips, pits, and craters.

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“…The mixing process plays a fundamental role in the quality of pharmaceuticals and food/dietary supplements, as tit can impact the homogeneity of the substances (which can contain up to 20 different ingredients) in their dosage form and also affect characteristics such as dissolution and stability (in the function of the distribution of functional excipients, such as lubricants and disintegrating agents) [ 1 , 2 ].…”

Section: Introductionmentioning

confidence: 99%

“…The choice of the right mixer device is paramount for the compounding pharmacies, as the quality of the mixture highly depends on it. This choice needs to be made through scientifically-based tests that show that any small amount of the sample from a bulk powder represents the physical and chemical characteristics of the entire bulk, and therefore, all dosage forms present the same amount of the active pharmaceutical ingredient (API) [ 2 , 7 ].…”

Section: Introductionmentioning

confidence: 99%

Ensuring Homogeneity in Powder Mixtures for Pharmaceuticals and Dietary Supplements: Evaluation of a 3-Axis Mixing Equipment

Marianni¹,

Polonini²,

Oliveira

2021

Pharmaceutics

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The mixing process plays a pivotal role in the quality of pharmaceuticals and food/dietary supplements, as it can impact the homogeneity of the substances in their dosage form and affect characteristics such as dissolution and stability. Thus, the choice of the right mixing device is paramount for compounding pharmacies. In this paper, we evaluated the mixing efficacy of a new 3-axis mixer device and determined its optimal working conditions. Three different formulations were compounded with the device and a total of 540 individual assays were performed by HPLC or ICP-MS to validate its use, in addition to a direct comparison among it and two alternative mixing methods. The 3-axis mixer device was able to provide homogeneous mixtures and finished capsules with adequate content uniformity with a broad range of conditions of use (mixing times from 2 to 8 min, and speed of rotation from 10 to 100 rpm). In addition, the device was superior to classical mixing methods (such as the use of manually shaken plastic bags) and at least equivalent to well-established ones (Y-shaped mixer). Finally, we proposed a cleaning procedure that was also adequate to prevent cross-contamination among products compounded with the same device.

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A review of current techniques for the evaluation of powder mixing

Abstract: This is a repository copy of A review of current techniques for the evaluation of powder mixing.

Cited by 82 publications

References 124 publications

Variability in content and dissolution profiles of MDMA tablets collected in the UK between 2001 and 2018 – A potential risk to users?

Variability in content and dissolution profiles of MDMA tablets collected in the UK between 2001 and 2018 – A potential risk to users?

Cavitation erosion behavior of microwave-processed Ni–40Cr₃C₂ composite clads: A parametric investigation using ultrasonic apparatus

Ensuring Homogeneity in Powder Mixtures for Pharmaceuticals and Dietary Supplements: Evaluation of a 3-Axis Mixing Equipment

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A review of current techniques for the evaluation of powder mixing

Abstract: This is a repository copy of A review of current techniques for the evaluation of powder mixing.

Cited by 82 publications

References 124 publications

Variability in content and dissolution profiles of MDMA tablets collected in the UK between 2001 and 2018 – A potential risk to users?

Variability in content and dissolution profiles of MDMA tablets collected in the UK between 2001 and 2018 – A potential risk to users?

Cavitation erosion behavior of microwave-processed Ni–40Cr3C2 composite clads: A parametric investigation using ultrasonic apparatus

Ensuring Homogeneity in Powder Mixtures for Pharmaceuticals and Dietary Supplements: Evaluation of a 3-Axis Mixing Equipment

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Cavitation erosion behavior of microwave-processed Ni–40Cr₃C₂ composite clads: A parametric investigation using ultrasonic apparatus