Tobramycin and Gentamycin elution analysis between two in situ polymerizable orthopedic composites

Abstract

This research analyzed Tobramycin and Gentamycin elution characteristics for two antibiotic-impregnated bone composites: PMMA-based Simplex P and the novel, hybrid, bioactive, CORTOSS. Experimental results were correlated with composite hydrophilicity and antibiotic phase partitioning behaviors. The phase partitioning experiment was conducted to understand antibiotic solubility in aqueous environments. By comparing experimental results with calculated data, antibiotic release behavior was predicted. Total Tobramycin elution percentages from CORTOSS and Simplex P were 12.5 and 6.4%, respectively. Total Gentamycin elution percentages from CORTOSS and Simplex P were 6.95 and 10.17%, respectively. Phase partitioning data indicate 100% of Tobramycin remains in aqueous phases, being extremely hydrophilic. This is supported by its calculated theoretical value (log P = - 7.32). Results suggest that Tobramycin elution can be attributed to composite hydrophilicity as well as its high degree of hydrophilicity. Fifteen percent of Gentamycin distributes in hydrophobic phases (log P = - 4.22). Despite a lower Gentamycin hydrophilicity, its release was affected by its complexation with polar salts in the leaching buffer, thereby increasing its elution potential, making it appreciably water soluble. CORTOSS is more hydrophilic; therefore the migration of aqueous liquids into the polymer network of CORTOSS facilitates greater antibiotic elution compared with hydrophobic Simplex P.

Synthesis of poly(acrylic acid)/sodium humate superabsorbent composite for agricultural use

“…The hypothetical structure for humic acid (or sodium humate), shown in Figure 8, contains free and bound phenolic OH groups, quinone structures, nitrogen and oxygen as bridge units, À ÀCOOH and À ÀNH 2 groups variously placed on aromatic rings. 17,18 The effect of the amount of sodium humate in the superabsorbent composite on the water absorbency is shown in Figure 9. When a prepared composite contained a small amount of sodium humate (< 5.3%), the water absorbency of the resulting product significantly improved, which may result from the increase in the amount of phenolic hydroxyl and acylamino groups in sodium humate structure in the system.…”

“…Similar results were reported in previous studies. 13,14,18 Effect of sodium humate Humic acids are thought to be complex aromatic macromolecules. The hypothetical structure for humic acid (or sodium humate), shown in Figure 8, contains free and bound phenolic OH groups, quinone structures, nitrogen and oxygen as bridge units, À ÀCOOH and À ÀNH 2 groups variously placed on aromatic rings.…”

“…15 It is a nutrient source for plants essentially helps move micronutrients from soil to plants, and improve water retention in the soil. 17,18 Its benefits for plant growing have been proven both experimentally and in the field. 18 To reduce costs, improve the comprehensive water-absorbing properties, and enhance nutritive functions of the superabsorbent materials for agriculture using, the grafting of AA polymer onto sodium humate (SH) and fabricating a composite that consists of polymer and SH was considered a priority.…”

“…17,18 Its benefits for plant growing have been proven both experimentally and in the field. 18 To reduce costs, improve the comprehensive water-absorbing properties, and enhance nutritive functions of the superabsorbent materials for agriculture using, the grafting of AA polymer onto sodium humate (SH) and fabricating a composite that consists of polymer and SH was considered a priority. In the present investiga-tion the authors report the synthesis of superabsorbent composites by graft copolymerization reaction of AA on SH.…”

Antibiotic delivery system using nano‐hydroxyapatite/chitosan bone cement consisting of berberine

“…12 The mixing procedure is convenient for CPCs used as a carrier for sustained release of antibiotic in the treatment of orthopedic infections. 13 Surgeons have mixed antibiotics such as Tobramycin, [14][15][16][17] Gentamicin, [18][19][20][21] Cefuroxime, 22 and Vancomycin 15,23 into bone cement at the surgery time to provide efficient concentrations of antimicrobial agents in the local or targeting the postsurgical infection.…”