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CN-121974290-A - Method and device for preparing flexible nano needle array structure in sandwich mode

CN121974290ACN 121974290 ACN121974290 ACN 121974290ACN-121974290-A

Abstract

The invention belongs to the technical field of nano material preparation, and discloses a method and a device for preparing a flexible nano needle array structure in a sandwich mode. The invention thoroughly solves the core pain point with low transfer rate and vulnerable structure of the traditional nano needle array by the sandwich type preparation and transfer integrated process, realizes the efficient separation and complete transfer of the nano column array from the original silicon substrate to the PDMS or hydrogel substrate by means of the design of middle sandwich isolation and mechanical stress separation, improves the transfer rate to more than 95%, has no fracture and deformation of the nano structure, and simultaneously solves the problem that the traditional rigid substrate cannot be attached to a non-planar tissue by the selection of the flexible/transparent substrate, realizes the optical observation feasibility of the interaction of the nano needle array and biological tissues, and fills the functional blank of the traditional opaque nano needle array.

Inventors

  • WANG CONG

Assignees

  • 苏州纳尔康医疗科技有限公司

Dates

Publication Date
20260505
Application Date
20251230

Claims (10)

  1. 1. The sandwich type method for preparing the flexible nano needle array structure is characterized by comprising the following steps of; 1) Providing a raw substrate that is patterned and to define a mask; The mask comprises a dielectric nano dot array, a Metal Auxiliary Chemical Etching (MACE) for forming a nano column array, a metal layer and a metal electrode, wherein the metal layer is deposited on a region to be etched in an original substrate; 2) Spin-coating an intermediate layer on the original substrate, and spin-coating a flexible/transparent substrate on the intermediate layer; Wherein the flexible/transparent substrate and the intermediate layer are formed of different materials; 3) Separating the nanopillar array from the original substrate and eliminating the intermediate layer by applying mechanical stress at the interface of the original substrate and the nanopillar array; wherein the elimination of the interlayer may be performed before/after separation from the original substrate; 4) And performing secondary etching on the nano-pillar array on the flexible/transparent substrate to form the nano-needle array.
  2. 2. The method of claim 1, wherein the chemical etching is performed to form a porous structure on the nano-pillars, the secondary etching includes ion etching, and the secondary etching is reactive ion etching in dry etching, and the secondary etching is performed to form a porous structure on the nano-pillars.
  3. 3. The method of claim 1, wherein the primary substrate comprises a silicon substrate and the flexible/transparent substrate is selected from the group consisting of hydrogel substrate and Polydimethylsiloxane (PDMS) substrate.
  4. 4. The method for preparing the flexible nano needle array structure by using the sandwich type according to claim 3, wherein the flexible/transparent substrate is a polydimethylsiloxane substrate, the weight ratio is 10:1, the spin coating speed is 100-6000rpm, the time is 10min, the polymerization temperature is 70 ℃ and the time is 2h, the polymerization is carried out at room temperature for overnight, and the different spin coating speeds correspond to the PDMS film thickness of 11000-12000nm at 1000rpm, 8150-9000nm at 1500rpm and 5000-5500nm at 4000 rpm.
  5. 5. The method for preparing the flexible nano needle array structure by the sandwich type according to claim 1, wherein the secondary etching is performed after the nano column array is separated from the original substrate, etching parameters can be regulated and controlled to obtain nano needles with preset aspect ratios, the concentration of MACE etching liquid H 2 O 2 in the chemical etching is 1% -4%, and the secondary etching adopts reactive ion etching in SF 6 atmosphere, wherein the power is 200-300W, and the pressure is 10-100mTorr.
  6. 6. The nanoneedle array structure formed according to any one of claims 1 to 5, wherein the nanoneedles are biodegradable, the nanoneedles are formed by secondarily etching porous/nonporous nanopillars, the porous structure of the nanopillars can be maintained, the nonporous nanopillars can be processed into the porous structure by secondarily etching, the porosity is 80% -100%, the length is preferably 1-20 μm, the maximum diameter is preferably 10-1000nm, the nanoneedles can be adjusted to other suitable sizes according to practical application scenes, the number of the nanoneedles in the array is not less than 100, the array density can be uniformly distributed/arranged at intervals according to different densities, and the array density can be optimized according to requirements.
  7. 7. The method of claim 6, wherein the nanoneedle is loaded with one or more therapeutic and diagnostic agents, the nanoneedle is attached to the non-planar tissue via a flexible substrate, and the nanoneedle is attached to human and animal tissue, and the loaded therapeutic/diagnostic agent is locally delivered, thereby achieving accurate administration/diagnostic sampling.
  8. 8. The device for preparing the flexible nano-needle array structure by the sandwich type according to claim 1, which is characterized by comprising a nano-pillar array formed on a raw substrate; the interlayer is attached to the original substrate and partially covers the nano-pillar array; a flexible/transparent substrate covering the remaining array of nanopillars and adjacent to and above the intermediate layer; The intermediate layer is optionally SU-8/PC-1500, which functions to isolate the original substrate from the flexible/transparent substrate.
  9. 9. The method for preparing the flexible nano needle array structure by using the sandwich type according to claim 1, wherein the eliminating intermediate layer uses RR41 remover, the concentration is 5% -10%, the treatment temperature is 80-90 ℃ and the time is 5-10 minutes, the secondary etching is carried out by monitoring the etching end point in real time through an optical emission spectrum to ensure that the conical end of the nano needle is formed, the interfacial tension between the intermediate layer material and the flexible substrate is 30-40 mN/m to ensure that no residue exists during stripping, the number of the nano needles in the array exceeds 10,000, and the density is adjustable to 100-1000 needles/mm < 2 >.
  10. 10. The nanoneedle array structure of claim 6, wherein the biodegradable nanoneedle has a 30-day degradation rate of 40% -60% and a 60-day degradation rate of 80% or more in simulated body fluid at pH 7.4 and 37 ℃ and no toxic residue.

Description

Method and device for preparing flexible nano needle array structure in sandwich mode Technical Field The invention belongs to the technical field of nano material preparation, in particular to a method and a device for preparing a flexible nano needle array structure in a sandwich mode, and further relates to application of the nano needle array, wherein the nano needle can form a solid, porous or double-porosity structure, and is suitable for medical scenes such as biological tissue interaction, biopsy, local delivery of biological agents and the like. Background The nano structure is widely applied to various fields such as photoelectric equipment, sensors, medical equipment and the like, wherein the nano needle array is used as an emerging medical instrument form, has remarkable effect in biopsy and drug delivery applied to biological systems and medical fields, is a high-aspect-ratio nano-scale material and can be divided into solid, porous or hollow nano needles; Conventional nanoneedle arrays are fabricated on opaque and rigid semiconductors, which typically have a transfer rate of less than 80% and a limited loading capacity of 1-2 μg/cm2, which limits their functionality in medical applications, on the one hand, the opacity of the nanoneedle array makes its interaction with biological tissue challenging to observe by optical microscopy techniques, and on the other hand, the rigidity of the nanoneedle array renders it unable to conform to non-planar tissue surfaces and is prone to fracture when deformed, reducing the application effect on tissue, and in addition, many of the prior art nanoneedle arrays are non-porous (solid) structures, typically non-degradable, and have limited ability to absorb substances, which is difficult to efficiently carry molecules from tissue samples or therapeutic/diagnostic agents to be applied to tissue, while the transfer rate of the nanoarray is low, the structural stability is insufficient, which further limits their practical application in conventional fabrication methods. In view of the above-mentioned drawbacks and shortcomings of the prior art, the present invention provides a method and apparatus for preparing a flexible nanoneedle array structure in a sandwich manner, which can realize efficient separation and transfer of the nanoarray in a simple and effective manner by optimizing process parameters and transfer modes, and solve multiple shortcomings of the conventional nanoneedle array in transparency, flexibility, loading capacity, transfer rate and structural stability. Disclosure of Invention In order to solve the problems in the prior art, the invention provides a method and a device for preparing a flexible nano needle array structure in a sandwich mode, the method is simple and convenient to operate and high in controllability, and the prepared nano needle array has flexibility, transparency, high porosity and excellent biocompatibility, is suitable for various medical scenes, and comprises the following steps of; 1) Providing a raw substrate that is patterned and to define a mask; The mask comprises a dielectric nano dot array, a Metal Auxiliary Chemical Etching (MACE) for forming a nano column array, a metal layer and a metal electrode, wherein the metal layer is deposited on a region to be etched in an original substrate; 2) Spin-coating an intermediate layer on the original substrate, and spin-coating a flexible/transparent substrate on the intermediate layer; Wherein the flexible/transparent substrate and the intermediate layer are formed of different materials; 3) Separating the nanopillar array from the original substrate and eliminating the intermediate layer by applying mechanical stress at the interface of the original substrate and the nanopillar array; wherein the elimination of the interlayer may be performed before/after separation from the original substrate; 4) And performing secondary etching on the nano-pillar array on the flexible/transparent substrate to form the nano-needle array. Preferably, the chemical etching may form the nano-pillars into a porous structure, the secondary etching includes ion etching and is reactive ion etching in dry etching, and the secondary etching may also form the nano-pillars into a porous structure. Preferably, the original substrate comprises a silicon substrate, and the flexible/transparent substrate may be selected from a hydrogel substrate/a polydimethylsiloxane substrate. Preferably, when the flexible/transparent substrate is a polydimethylsiloxane substrate, the weight ratio is 10:1, the spin coating speed is 100-6000rpm, the time is 10min, the polymerization temperature is 70 ℃ and the time is 2h, the substrate is placed at room temperature overnight, and different spin coating speeds correspond to the PDMS film thickness of 11000-12000nm at 1000rpm, 8150-9000nm at 1500rpm and 5000-5500nm at 4000 rpm. Preferably, the secondary etching is performed after the nanopillar array is separated from the