Controlled Release of Ropivacaine from Single-Armed (1-PCL) and Four-Armed PCL (4-PCL) Microspheres

Sustained release of anesthesia has shown great promise in the treatment of chronic pain in patients. In this research, we used neutralized ropivacaine as an anesthesia and poly(ε-caprolactone) (PCL) with different architectures to systematically study how these architectures affect the release of ropivacaine. After optimizing the parameters of the preparation of microspheres, ropivacaine-loaded 1-PCL microspheres and 4-PCL microspheres were obtained. Fourier Transform infrared spectra (FT-IR) and X-ray diffraction spectra (XRD) confirmed that ropivacaine was encapsulated within the microsphere rather than inserted on the surface of the microsphere. Ropivacaine was found to be buried deeper in the 1-PCL microsphere than in the 4-PCL microsphere. In vitro release assay revealed that small crystalline grains interfered with ropivacaine release in 4-PCL microspheres during the initial release period, but then two kinds of microspheres showed a similar ropivacaine release rate. We basically proved that the architecture of PCL has a negligible effect on ropivacaine release. Cell proliferation test revealed that the release of products from the microspheres resulted in insignificant toxicity towards mammalian cells.

[1]  M. Edirisinghe,et al.  Effect of copolymer composition on particle morphology and release behavior in vitro using progesterone , 2018, Materials & Design.

[2]  L. H. Lundstrøm,et al.  Volume of ropivacaine 0.2% and common peroneal nerve block duration: a randomised, double‐blind cohort trial in healthy volunteers , 2018, Anaesthesia.

[3]  Ropivacaine , 2018, Reactions Weekly.

[4]  Xuesi Chen,et al.  Long-acting hydrogel/microsphere composite sequentially releases dexmedetomidine and bupivacaine for prolonged synergistic analgesia. , 2018, Biomaterials.

[5]  M. Kaur,et al.  Comparison of complications in midlines versus central venous catheters: Are midlines safer than central venous lines? , 2018, American journal of infection control.

[6]  M. Tawfick,et al.  Carbapenem-resistant Gram-negative bacteria associated with catheter-related bloodstream infections in three intensive care units in Egypt , 2018, European Journal of Clinical Microbiology & Infectious Diseases.

[7]  Xuesi Chen,et al.  Precision-guided long-acting analgesia by Gel-immobilized bupivacaine-loaded microsphere , 2018, Theranostics.

[8]  J. Geitung,et al.  CT guided neurolytic blockade of the coeliac plexus in patients with advanced and intractably painful pancreatic cancer , 2018, Scandinavian journal of pain.

[9]  B. He,et al.  Synthesis, characterization, and property of biodegradable PEG-PCL-PLA terpolymers with miktoarm star and triblock architectures as drug carriers , 2018, Journal of biomaterials applications.

[10]  Meng Chang,et al.  Local anaesthetic pain relief therapy: In vitro and in vivo evaluation of a nanotechnological formulation co-loaded with ropivacaine and dexamethasone. , 2017, Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie.

[11]  J. Villanueva,et al.  Turning the screw even further to increase microparticle retention and ocular bioavailability of associated drugs: The bioadhesion goal. , 2017 .

[12]  L. Tong,et al.  Preparation of novel biodegradable ropivacaine microspheres and evaluation of their efficacy in sciatic nerve block in mice , 2016, Drug design, development and therapy.

[13]  Na Qiang,et al.  Synthesis of functional polyester for fabrication of nano-fibrous scaffolds and its effect on PC12 cells , 2016, Journal of biomaterials science. Polymer edition.

[14]  J. Warzywoda,et al.  In-vitro degradation characteristics of poly(e-caprolactone)/poly(glycolic acid) scaffolds fabricated via solid-state cryomilling , 2015, Journal of biomaterials applications.

[15]  G. Zhai,et al.  Lipid nanocapsules for transdermal delivery of ropivacaine: in vitro and in vivo evaluation. , 2014, International journal of pharmaceutics.

[16]  Daping Quan,et al.  Synthesis of pendent carboxyl-containing poly(ε-caprolactone-co-β-malic acid)-block-poly(l-lactide) copolymers for fabrication of nano-fibrous scaffolds , 2012 .

[17]  A. C. Vieira,et al.  Mechanical study of PLA-PCL fibers during in vitro degradation. , 2011, Journal of the mechanical behavior of biomedical materials.

[18]  A. Almeida,et al.  Effectiveness of the association between carbamazepine and peripheral analgesic block with ropivacaine for the treatment of trigeminal neuralgia , 2010, Journal of pain research.

[19]  T. Hong.  THE SUSTAINED-RELEASE OF ROPIVACAINE PLGA MICROSPHERES IN THE MOUSE SCIATIC NERVE , 2010 .

[20]  D. Faulds,et al.  Ropivacaine , 2000, Drugs.

[21]  G. Harrison.  The use of epidural ropivacaine in high doses for the management of pain from invasive carcinoma of the cervix , 1999, Anaesthesia.

[22]  K.,et al.  Central nervous and cardiovascular effects of i.v. infusions of ropivacaine, bupivacaine and placebo in volunteers. , 1997, British journal of anaesthesia.