Fabrication of pure-drug microneedles for delivery of montelukast sodium

Single-Administration Long-Acting Microarray Patch with Ultrahigh Loading Capacity and Multiple Releases of Thermally Stable Antibodies

“…Another approach to increase the drug loading in the patch is to increase the size of each individual MN and overall size of the MA patch. Nevertheless, there are certain limits to those factors to avoid pain and discomfort to patients. , Different approaches have been investigated to maximize the drug loading efficiency of MA patches . Inspired by these challenges and prior work, our goal was to maximize the loading capacity of the MA by developing a powder-filling technique, which would maximize the amount of therapeutics, specifically Abs, in the MA spaces (Figure b,c).…”

“… 41 , 42 Different approaches have been investigated to maximize the drug loading efficiency of MA patches. 25 Inspired by these challenges and prior work, our goal was to maximize the loading capacity of the MA by developing a powder-filling technique, which would maximize the amount of therapeutics, specifically Abs, in the MA spaces ( Figure 1 b,c). Starting from a positive MA master mold patterned on a silicon wafer using a two-photon polymerization technique, a negative mold was replicated by pouring and subsequently curing a PDMS elastomer onto the silicon wafer.…”

“…The most common drug loading method uses liquid casting onto an MA mold and usually results in very low loading capacity (less than 1 mg into a 1 × 1 cm 2 MA patch) − due to the presence of solvents in the casting process or the solubility and dispersity of the drugs. Continuous efforts have been made in the field to improve the loading capacity of MA including optimizing MA geometries, solubility of therapeutics, and casting methods. , Additionally, some of the MA manufacturing processes (e.g., micromolding) may use high temperatures (up to 60–80 °C), , which can be detrimental to heat-labile molecules such as Abs. Furthermore, most MA patches are currently designed for instantaneous release of Abs right after administration, thus requiring repeated dosing over time to sustain therapeutic Ab levels in systemic circulation …”

“…Continuous efforts have been made in the field to improve the loading capacity of MA including optimizing MA geometries, solubility of therapeutics, and casting methods. 24 , 25 Additionally, some of the MA manufacturing processes (e.g., micromolding) may use high temperatures (up to 60–80 °C), 26 , 27 which can be detrimental to heat-labile molecules such as Abs. Furthermore, most MA patches are currently designed for instantaneous release of Abs right after administration, thus requiring repeated dosing over time to sustain therapeutic Ab levels in systemic circulation.…”

Soft Injectable Sutures for Dose‐Controlled and Continuous Drug Delivery

“…Transdermal drug delivery using microneedles, for example, offers a relatively painless route of drug delivery through interstitial fluid, where the release of drugs can be sustained over long periods of time and tuned through size, number, and matrix composition of microneedles. [ 2,6–20 ] However, microneedles can still cause skin inflammation, may not penetrate reliably in all skin types, are prone to breakage, and can peel off due to sweating or motion, which makes them highly unreliable for drug delivery. One of the new classes of drug‐delivery systems that is being studied is injectable hydrogels, which allow for painless delivery of therapeutics to desired delivery sites.…”