Rapid Monitoring of Graphene Exfoliation Using NMR Proton Relaxation

Introduction: Capsaicin (8-methy-N-vanillyl-6-nonenamide), a potential analgesic derived from Capsicum annuum (Chili peppers), widely used from ancient times for its pharmacological activities such as anti-inflammatory, anti-oxidant and analgesic and provides relief from migraine and diabetes. But for obvious reasons, capsaicin cannot be administered directly. The present work was designed with a focus to comply with mandatory requirement in various pharmacopeias to know the actual content of API present in final formulations. The formulation (TS3) consisting of 3% lipid, with 4:6 ratio of the polymer and solvent, was found to be the optimized formulation, which gave the best evaluation with regard to the particle size (97.03±2.68) nm, polydispersity index (0.20±0.00), higher zeta potential (61.28±2.06) mv, morphological studies and highest drug entrapment efficiency (68.34±4.24)%. The prepared transferosome formulation was subjected to characterization by validated HP-TLC method consisting of N-Hexane: Tert- Iso-butyl-methyl ether in ratio (5:15) v/v. Linearity was performed in the range of 50-1500 ng/spot with LOD/LOQ 50 ng and 150 ng, with regression analysis (R) of 99.91%. Recovery analysis was performed at 3 different levels at 80, 100 and 120 with an average recovery of 106.97%, respectively. Till now, no analytical method has been reported, associated with the characterization of pharmaceutical nano-forms (Capsaicin), like transferosomes. Thus, the maiden validated HP-TLC method for concurrent analysis of capsaicin as API in nano-transferosome may be employed in process quality control of formulations containing the said API. Background: The irritability and adverse effects post application, leading to inflammation and neural pain at the site of administration of newly Capsaicin API and its chemical entities and marketed formulations are usually related to poor permeability, leading to drug complex reactions in the development phases or therapeutic failure along with the quantification of the same in blood plasma. However, advancement in drug formulations with the use of polymer: alcohol ratio and modernized analytical techniques for the quantification of Pharmaceutical APIs seems to be emerging and promising for overcoming pain and related inflammatory complications by formulating the APIs in Transferosome formulation with Validated HP-TLC technique being used as an effective economic and precise tool for quantitative analysis of APIs in their respective nano-forms. Objective: The study proposes a novel standardized method development and validation of pharmaceutical nanoforms with Capsaicin as API. Method: Capsaicin Transferosomes were formulated using Ultra probe sonication by utilizing different proportions of phospholipid 90G dissolved in a mixture of ethanol and propylene glycol. The formulation was subjected to Dynamic Light Scattering (DLS) technique for nano-particle analysis followed by characterization with respect to particle size, polydispersity index, zeta potential and entrapment efficiency. The morphological study of vesicles was determined using SEM and TEM. A Validated HP-TLC method for the identification and determination of Capsaicin in transferosomes formulation was performed as per the ICH guidelines. Results: The formulation gave the best evaluation for particle size (97.03±2.68) nm, polydispersity index (0.20±0.00), higher zeta potential (61.28±2.06) mv, morphological studies (SEM & TEM) and highest drug entrapment efficiency (68.34±4.24)%. DSC thermograms and FTIR spectral patterns confirmed no physical interaction by polymers with API. The prepared formulation was then characterized using HP-TLC method. The best resolution was found in NHexane: Tert-Isobutyl methyl ether in a ratio of 5:15 v/v. The Rf was found to be 0.3±0.03. Linearity was performed in a range of 50-1500 ng/spot, with regression analysis (R) of 99.91% Further, recovery analysis was done at 3 different levels as 80, 100 and 120 with an average recovery of 106.97%. The LOD/LOQ was found to be 50 and 150 ng, respectively. Precision was carried out in which % RSD was found to be precise and accurate. Conclusion: The outcomes of the present study suggested that the proposed novel formulation analyzed by Validated planar chromatographic technique (HP-TLC) for Capsaicin quantification in nanoforms may be employed as a routine quality control method for the said API in various other formulations.

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Chromium powder as a reference material for the quality control of particle-size measurement by laser diffraction

Powder Technology ◽

10.1016/j.powtec.2005.05.041 ◽

2005 ◽

Vol 155 (1) ◽

pp. 85-91 ◽

Cited By ~ 2

Author(s):

N. Etxebarria ◽

G. Arana ◽

R. Antolín ◽

E. Diez ◽

G. Borge ◽

...

Keyword(s):

Particle Size ◽

Quality Control ◽

Reference Material ◽

Laser Diffraction ◽

Size Measurement ◽

Chromium Powder ◽

Particle Size Measurement

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Inspecting Insulin Products Using Water Proton NMR. I. Noninvasive vs Invasive Inspection

Journal of Diabetes Science and Technology ◽

10.1177/19322968211023806 ◽

2021 ◽

pp. 193229682110238

Author(s):

Marc B. Taraban ◽

Yilin Wang ◽

Katharine T. Briggs ◽

Yihua Bruce Yu

Keyword(s):

Quality Control ◽

Relaxation Rate ◽

Drug Product ◽

Proton Nmr ◽

Water Proton ◽

Proton Relaxation ◽

Content Uniformity ◽

Biologic Drugs ◽

Insulin Solution ◽

Insulin Pens

Background: There is a clear need to transition from batch-level to vial/syringe/pen-level quality control of biologic drugs, such as insulin. This could be achieved only by noninvasive and quantitative inspection technologies that maintain the integrity of the drug product. Methods: Four insulin products for patient self-injection presented as prefilled pens have been noninvasively and quantitatively inspected using the water proton NMR technology. The inspection output is the water proton relaxation rate R2(1H2O), a continuous numerical variable rather than binary pass/fail. Results: Ten pens of each product were inspected. R2(1H2O) displays insignificant variation among the 10 pens of each product, suggesting good insulin content uniformity in the inspected pens. It is also shown that transferring the insulin solution out of and then back into the insulin pen caused significant change in R2(1H2O), presumably due to exposure to O2 in air. Conclusions: Water proton NMR can noninvasively and quantitatively inspect insulin pens. wNMR can confirm product content uniformity, but not absolute content. Its sensitivity to sample transferring provides a way to detect drug product tampering. This opens the possibility of inspecting every pen/vial/syringe by manufacturers and end-users.

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Thermogravimetric Analysis (TGA) of Graphene Materials: Effect of Particle Size of Graphene, Graphene Oxide and Graphite on Thermal Parameters

C – Journal of Carbon Research ◽

10.3390/c7020041 ◽

2021 ◽

Vol 7 (2) ◽

pp. 41

Author(s):

Farzaneh Farivar ◽

Pei Lay Yap ◽

Ramesh Udayashankar Karunagaran ◽

Dusan Losic

Keyword(s):

Particle Size ◽

Quality Control ◽

Graphene Oxide ◽

Thermogravimetric Analysis ◽

Low Cost ◽

Thermal Parameters ◽

Carbon Decomposition ◽

Size Number ◽

Carbon Combustion ◽

Oxygen Groups

Thermogravimetric analysis (TGA) has been recognized as a simple and reliable analytical tool for characterization of industrially manufactured graphene powders. Thermal properties of graphene are dependent on many parameters such as particle size, number of layers, defects and presence of oxygen groups to improve the reliability of this method for quality control of graphene materials, therefore it is important to explore the influence of these parameters. This paper presents a comprehensive TGA study to determine the influence of different particle size of the three key materials including graphene, graphene oxide and graphite on their thermal parameters such as carbon decomposition range and its temperature of maximum mass change rate (Tmax). Results showed that Tmax values derived from the TGA-DTG carbon combustion peaks of these materials increasing from GO (558–616 °C), to graphene (659–713 °C) and followed by graphite (841–949 °C) The Tmax values derived from their respective DTG carbon combustion peaks increased as their particle size increased (28.6–120.2 µm for GO, 7.6–73.4 for graphene and 24.2–148.8 µm for graphite). The linear relationship between the Tmax values and the particle size of graphene and their key impurities (graphite and GO) confirmed in this study endows the use of TGA technique with more confidence to evaluate bulk graphene-related materials (GRMs) at low-cost, rapid, reliable and simple diagnostic tool for improved quality control of industrially manufactured GRMs including detection of “fake” graphene.

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