Author/Editor     Resnik, Drago; Možek, Matej; Pečar, Borut; Janež, Andrej; Urbančič-Rovan, Vilma; Iliescu, Ciprian; Vrtačnik, Danilo
Title     In vivo experimental study of noninvasive insulin microinjection through hollow si microneedle array
Type     članek
Vol. and No.     Letnik 9, št. 40
Publication year     2017
Volume     str. 1-17
Language     eng
Abstract     An experimental study of in vivo insulin delivery through microinjection by using hollow silicon microneedle array is presented. A case study was carried out on a healthy human subject in vivo to determine the influence of delivery parameters on drug transfer efficiency. As a microinjection device, a hollow microneedle array (13 X 13 mm2) having 100 microneedles (220 [micro]m high, 130 [micro]m-outer diameter and 50 [micro]m-inner diameter) was designed and fabricated using classical microfabrication techniques. The efficiency of the delivery process was first characterized using methylene blue and a saline solution. Based on these results, the transfer efficiency was found to be predominantly limited by the inability of viable epidermis to absorb and allow higher drug transport toward the capillary-rich region. Two types of fast-acting insulin were used to provide evidence of efficient delivery by hollow MNA to a human subject. By performing blood analyses, infusion of more-concentrated insulin (200 IU/mL, international units (IU)) exhibited similar blood glucose level drop (5-7%) compared to insulin of standard concentration (100 IU/mL), however, significant increase of serum insulin (40-50%) with respect to the preinfusion values was determined. This was additionally confirmed by a distinctive increase of insulin to C-peptide ratio as compared to preinfusion ratio. Moreover, we noticed that this route of administration mimics a multiple dose regimen, able to get a steady state for insulin plasma concentration.
Keywords     votla Si mikronaična matrika
mikroinjektiranje
in vivo dajanje insulina
hollow Si microneedle array
microinjection
in vivo insulin delivery