Table 4 Summary of researches on traditional polymeric LAs delivery system
From: Advances of Nano-Structured Extended-Release Local Anesthetics
Reference Number | Polymer | LAs | Morphology | Diameter | Release profile | Analgesic efficacy |
|---|---|---|---|---|---|---|
[122] | Poly (d, l-lactic acid) | Lidocaine | Nanosphere | 250–820 nm | 24–30 h | None |
[123] | Poly (d, l-lactide-co-glycolide | Procaine hydrochloride | Nanoparticle | 157.1–209.5 nm | > 6 h | None |
[131] | Poly (d, l-lactide-co-glycolide | Ropivacaine | Nanosphere | 162.7 ± 1.5 nm | None | None |
[125] | Alginate/bis (2-ethylhexyl) sulfosuccinate and alginate/chitosan | Bupivacaine | Nanoparticle | 926.5 ± 32 and 944.4 ± 98 nm | > 900min | Both of study groups prolong anesthetic efficacy compared to plain bupivacaine in paw withdrawal to pressure threshold in sciatic nerve blockade (n = 6–7, p < 0.01) |
[124] | Poly (ε-caprolactone) | Benzocaine | Nanocapsule | 149.4–209.2 | None | None |
[132] | Poly(l-lactide) | Benzocaine | Nanocapsule | 120 nm | Up to 480 min | Prolonged the duration of analgesia in 0.006% or 0.06% benzocaine (BZC) up to 180 and 300 min respectively; increased intensity approximately twofold (p < 0.001), compared with 0.06% plain BZC in sciatic nerve blockade (n = 6–7) |
[127] | Poly (ε-caprolactone) | Lidocaine | Nanosphere | 449.6 nm | 350 min | Nanospheric lidocaine significantly (p < 0.001) increased the intensity and duration of analgesia, compared with free lidocaine in sciatic nerve block (n = 5) |
[133] | Alginate/chitosan | Bupivacaine | Nanoparticle | None | > 900 min | The total analgesic in infraorbital nerve blockade was improved by 1.4-fold (p < 0.001) with bupivacaine nanoparticle compared to bupivacaine(n = 7) |
[133] | Poly(ε-caprolactone) | Lidocaine or prilocaine | Nanocapsule | None | > 18 h | Nanocapsule showed significant increase in duration of anesthesia (p < 0.01) and the maximum possible effect (p < 0.01), compared to the commercial formulation in tail flick test (n = 6) |
[128] | Poly(lactide-co-glycolide) | Bupivacaine | Nanoparticle | 150 ± 10 nm | 35 days | Nanoparticle showed significant decrease on mechanically evoked response from day 1–14 days compared to blank particle |
[134] | N-isopropylacylamide and acrylic acid | Bupivacaine | Gel | None | 60 days | None |
[135] | Tyrosine-polyethylene glycol-derived poly (ether carbonate) co-polymers and silica-based xerolgel | Bupivacaine or mepivacaine | Gel | None | 7 days | Significant decrease of mechanical hypersensitivity in study group from 0.5 to 24 h compared to control and sham group (p < 0.05, n = 5) |
[136] | Polysaccharide | Bupivacaine | Gel | None | 120h | Significantly increased total force in study group (201.3) than LB group (144.4) to induce allodynia from 0–120 h (p = 0.0005, n = 20) |
[129] | Poly (lactic-co-glycolic acid) | Bupivacaine | Nanofiber (suture) | 800-1000nm | 12 days | The greatest degree of analgesia was achieved at approximately 3 days, and significant relief was observed from 1 to 7–9 days compared to drug free suture group (n ≥ 6, p < 0.05= |