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. 2015 Jul 27:4:147.
doi: 10.4103/2277-9175.161563. eCollection 2015.

Thermoanalytical characterization of clindamycin-loaded intravitreal implants prepared by hot melt extrusion

Lana Tamaddon  1 , Seyed Abolfazl Mostafavi  1 , Reza Karkhane  2 , Mohammad Riazi-Esfahani  2 , Farid Abedin Dorkoosh  3 , Morteza Rafiee-Tehrani  3
Affiliations

Thermoanalytical characterization of clindamycin-loaded intravitreal implants prepared by hot melt extrusion

Lana Tamaddon et al. Adv Biomed Res. .

Abstract

Background: The aim of the present study was to evaluate a non-destructive fabrication method in for the development of sustained-release poly (L, D-lactic acid)-based biodegradable clindamycin phosphate implants for the treatment of ocular toxoplasmosis.

Materials and methods: The rod-shaped intravitreal implants with an average length of 5 mm and a diameter of 0.4 mm were evaluated for their physicochemical parameters. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC), Fourier-transform infrared (FTIR), and nuclear magnetic resonance (1H NMR) studies were employed in order to study the characteristics of these formulations.

Results: Drug content uniformity test confirmed the uniformity in different implant batches. Furthermore, the DSC, FTIR, and 1H NMR studies proved that the fabrication process did not have any destructive effects either on the drug or on the polymer structures.

Conclusion: These studies showed that the developed sustained-release implants could be of interest for long-term sustained intraocular delivery of clindamycin, which can provide better patient compliance and also have good potential in terms of industrial feasibility.

Keywords: Clindamycin phosphate; D-lactic acid); intravitreal implant; melt extrusion; poly (L.

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Conflict of interest statement

Conflict of Interest: None declared.

Figures

Figure 1
Figure 1
Macroscopic view of the fabricated implants
Figure 2
Figure 2
Microscopic images of implants: (a) before immersing in the release medium (b) 4 weeks and (c) 10 weeks after incubation
Figure 3
Figure 3
The in vitro release diagram of clindamycin from PLA implants (the values are shown as mean ± SD). Each data point represents the average of three samples
Figure 4
Figure 4
DSC thermograms of samples: (a) pure CLP, (b) pure PLA, (c) physical mixture of CLP/PLA, (d) lyophilized mixture of CLP/PLA, and (e) clindamycin-containing implants
Figure 5
Figure 5
General chemical structures of (a) PLA and (b) clindamycin phosphate. Reprinted with permission from references[2627]
Figure 6
Figure 6
Infrared spectra of (a) pure CLP, (b) pure PLA, (c) physical mixture PLA/CLP, and (d) CLP-containing implant
Figure 7
Figure 7
1H NMR of (a) pure clindamycin, (b) pure PLA, (c) and drug-loaded PLA implant
See this image and copyright information in PMC

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