Levofloxacin‐Loaded Microneedles Produced Using 3D‐Printed Molds for Klebsiella Pneumoniae Biofilm Control

Abstract

Additive manufacturing advancements contribute considerably to several fields and its use in the medical field is gaining attention due to its easily customizable option (patient-specific), low cost, and fast turnout time in developing drug delivery and diagnostic tools. Herein, the fabrication of a microneedle (MN) platform is reported using a stereolithography 3D printer, varying the 3D printing angle and aspect ratio (2:1, 3:1, and 4:1). The optimal printing angle is 30°, resulting in needle tip and base diameters of ≈50 and ≈330 μm and heights of ≈550/850/1180 μm. Polyvinyl alcohol (PVA) MNs produced with varying levofloxacin concentrations show variability of ≈4% in tip and 3% base diameters and 15% in height compared to the 3D-printed MNs. Geometry B is used to produce levofloxacin-loaded PVA MNs and tested against Klebsiella pneumoniae colony biofilms. Levofloxacin is released gradually, as assessed by spectrofluorimetry. The minimum inhibitory concentration of levofloxacin against the K. pneumoniae clinical isolate is 4 μg mL −1 but this concentration is insufficient to cause any effect on K. pneumoniae biofilms. Only concentrations ≥32 μg mL −1 are statistically different compared to the unloaded MNs. 3D printing is an attractive solution to produce molds for fabricating biopolymeric MNs for topical drug delivery. IntroductionThe skin has been a lucrative target for drug delivery and diagnosis in medicine. Since the skin is the largest organ in the body,

Polymeric Microneedles for Health Care Monitoring: An Emerging Trend

“…Casting is followed by a solidification step to form the MNs, which can then be peeled from these molds. 73,86 Some polymers may further require cross-linking to improve mechanical strength, control the swelling behavior, or enhance MN stability. 87 Sensor-Integrated Microneedles.…”

“…Swellable MNs are typically fabricated by casting/molding swellable polymers into PDMS master molds with an inverse geometry of the MNs. Casting is followed by a solidification step to form the MNs, which can then be peeled from these molds. , Some polymers may further require cross-linking to improve mechanical strength, control the swelling behavior, or enhance MN stability …”

“…Moreover, complex designs are time-consuming, and only certain substrates can be used. Finally, 3D printing, 73 an additive manufacturing technique, has been used to build MNs layer-by-layer from digital designs. This technique is suitable for rapid prototyping and customization of complex geometries from a variety of available resins, but is limited by its resolution (lower compared to traditional MN fabrication techniques), and lower mechanical strength.…”

Microneedles Patch: Design, Fabrication and Applications

“…Another study reported the fabrication of a microneedle platform using an SLA 3D printer, varying the 3D printing angle and aspect ratio. The investigators concluded that the optimal printing angle was 30°, resulting in needle tip and base diameters of ≈50 and ≈330 μm and heights of ≈550/850/1180 µm [299]. Yang et al developed 3D-printed morphology-customized microneedles with excellent transdermal drug delivery efficiency [300].…”

Microneedles’ Device: Design, Fabrication, and Applications

“…Another study reported the fabrication of a microneedle platform using an SLA 3D printer, varying the 3D printing angle and aspect ratio. The investigators concluded that the optimal printing angle was 30 • , resulting in needle tip and base diameters of ≈50 and ≈330 µm and heights of ≈550/850/1180 µm [293]. Yang et al developed 3D-printed morphology-customized microneedles with excellent transdermal drug delivery efficiency [294].…”