Effect of Encapsulating Arginine Containing Molecules on PLGA: A Solid-State NMR Study

Guilbaud, Jean‐Baptiste; Baker, H. de C.; Clark, Brian C.; Meehan, E. J.; Khimyak, Yaroslav Z.

doi:10.1002/jps.22019

Cited by 8 publications

(3 citation statements)

References 67 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Full peak assignment has been carried out by this group, and this was used to identify the peaks in the spectra of the CIP/amino acid ASDs. The 13 C spectra of the ball milled pure amino acids match those of crystalline GLU [29], CYS [30] and ARG [31], which have previously been described. The peaks present in these spectra are sharp in appearance, confirming that ball milling did not alter the crystallinity, ionization state or intermolecular interactions of the amino acids.…”

Section: Solid-state Nuclear Magnetic Resonancesupporting

confidence: 76%

Preparation and characterization of amorphous ciprofloxacin-amino acid salts

Mesallati

Conroy

Hudson

et al. 2017

European Journal of Pharmaceutics and Biopharmaceutics

View full text Add to dashboard Cite

The amorphization of the poorly soluble drug ciprofloxacin (CIP) may be facilitated by the use of a suitable stabilizer. In this study seven amino acids, with various side chain properties, were evaluated in this regard. Solid dispersions were prepared by ball milling 1:1 molar ratios of CIP with the amino acids, and their solid-state and pharmaceutical properties were then examined. Fully X-ray amorphous solid dispersions were obtained with aspartic acid, glutamic acid, cysteine and arginine. In each case, evidence of salt formation between the drug and amino acids was found via Fourier transform infrared spectroscopy and solid-state nuclear magnetic resonance. In contrast, semi-crystalline solid dispersions were obtained with serine, alanine and glycine. The glass transition temperatures of the amorphous salts were significantly higher than those of the starting materials, and they remained fully X-ray amorphous during long-term stability studies. Significant improvements in the solubility of CIP were also observed with the amorphous salts in water and simulated biological fluids, over and above that of the corresponding physical mixtures. In permeability studies on the other hand, the amorphous aspartate and glutamate salts were found to be less permeable than the pure drug, whereas formulation as an amorphous salt containing cysteine or arginine increased the permeability of CIP. Therefore, while amorphous salt formation with amino acids appears to be a suitable means of improving the thermal stability and solubility of CIP, in some cases this is associated with a decrease in permeability.

show abstract

Section: Solid-state Nuclear Magnetic Resonancesupporting

confidence: 76%

Preparation and characterization of amorphous ciprofloxacin-amino acid salts

Mesallati

Conroy

Hudson

et al. 2017

European Journal of Pharmaceutics and Biopharmaceutics

View full text Add to dashboard Cite

show abstract

“…A series of spectra at various contact times (t) were recorded for HNT/ CB [8] complex under proton pulse cross-polarization conditions (Figure 5a). Under these circumstances, signal intensities depend on t according to the relationship [30] where I 0 is the maximum observable signal intensity and T I 11 is the proton longitudinal relaxation time in the rotating frame associated to each group resonating. T CH depends on the number of nuclei involved in cross polarization and on their disposition.…”

Section: Physico-chemical Characterization Of Hnt/cb[8] Nanohybridsmentioning

confidence: 99%

Ecocompatible Halloysite/Cucurbit[8]uril Hybrid as Efficient Nanosponge for Pollutants Removal

et al. 2016

View full text Add to dashboard Cite

Hybrid materials based on halloysite nanotubes (HNT) and cucurbit [8]uril (CB[8]) were prepared with the aim to obtain efficient nanosponges towards hydrocarbons both in liquid and vapor phases. The loading on both HNT surfaces and the hybrid morphology were evidenced by FTIR spectroscopy, thermogravimetric analysis and scanning electron microscopy. In order to highlight the interactions in the hybrid 13 C { 1 H} CP-MAS NMR experiments were performed. The aqueous colloidal stability of HNT/CB[8] was highlighted through z potential and dynamic light scattering measurements. The HNT/CB[8] composite was employed as nanosponge to capture aromatic oils in aqueous phase as evidenced by fluorescence emission spectra of pyrene. These results were correlated with the adsorption capacity of the hybrid toward toluene in vapor phase. This paper provides an efficient way to prepare a biocompatible hybrid material that could be used as a potential multi-pockets nano-container for decontamination of polluted water and/or air.

show abstract

“…A wide variety of natural and synthetic biodegradable polymers have received considerable attention in recent years for controlled delivery and sustained release of drugs . Encapsulation in a polymeric microsphere can have a significant effect on the dynamic and physical properties of the drug . Several spectroscopic and microscopic techniques such as Raman spectroscopy, Fourier‐transform infrared spectroscopy, transmission electron microscopy, scanning electron microscopy, and atomic force microscopy have been used for the characterization of drug‐loaded poly lactic‐co‐glycolic acid (PLGA) microspheres.…”

Section: Introductionmentioning

confidence: 99%

Solution dynamics of 5‐fluorouracil entrapped in poly lactic‐co‐glycolic acid (PLGA) microsphere—A study with 1D selective NMR methods

Kumar

Pal

2018

Magnetic Reson in Chemistry

View full text Add to dashboard Cite

In this report, our main focus is to introduce a set of one‐dimensional (1D) NMR methods based on chemical shift, relaxation, and magnetization transfer, namely, NOE and chemical exchange involving selective pulse excitation to study the solution dynamics of drug in free and encapsulated state within polymeric microsphere. In this regard 5‐fluorouracil (5‐FU) loaded poly lactic‐co‐glycolic acid (PLGA) microspheres are prepared as model system via standard water‐in‐oil‐in‐water emulsification method. One‐dimensional 1H and 19F nuclear magnetic resonance (NMR) spectra of 5‐FU in presence of PLGA microspheres presented a significant change in linewidth and relaxation rates compared with free 5‐FU confirming encapsulation. Furthermore, loss of coupling pattern in 1H and 19F NMR of PLGA encapsulated 5‐FU as compared with free 5‐FU suggests an enhanced –NH and –H2O protons exchange dynamics in the interior of the microsphere indicating hydrated microsphere cavity. Quantification of exchange dynamics in case of free and PLGA‐encapsulated 5‐FU was attempted employing 1D selective NOESY and 1D multiply selective inversion recovery experiments. Analysis of the exchange rates confirmed existence of more than one kind of water population within the cavity as mentioned in an earlier solid state NMR report.

show abstract

Effect of Encapsulating Arginine Containing Molecules on PLGA: A Solid-State NMR Study

Cited by 8 publications

References 67 publications

Preparation and characterization of amorphous ciprofloxacin-amino acid salts

Preparation and characterization of amorphous ciprofloxacin-amino acid salts

Ecocompatible Halloysite/Cucurbit[8]uril Hybrid as Efficient Nanosponge for Pollutants Removal

Solution dynamics of 5‐fluorouracil entrapped in poly lactic‐co‐glycolic acid (PLGA) microsphere—A study with 1D selective NMR methods

Contact Info

Product

Resources

About