A biocompatible microneedle patch for subcutaneous laser delivery

Abstract

The present invention discloses a microneedle patch [100] for subcutaneous laser delivery. Particularly, a microneedle patch for subcutaneous laser delivery for cosmetic surgeries e.g. laser based pigmented lesion removal and tattoo removal is disclosed. The disclosed microneedle patch for subcutaneous laser delivery facilitates the delivery of laser to the deeper layers of the skin without falling in intensity resulting into efficient therapeutic results without requiring additional surgical procedures and makes the overall treatment cost effective. Conclusively, the microneedle patch for subcutaneous laser delivery disclosed herein is devoid of the drawbacks of prior arts, and provide economic and efficient removal of subdermal pigmented lesions and accreted chromophores.

Description

[0001] A BIOCOMPATIBLE MICRONEEDLE PATCH FOR SUBCUTANEOUS LASER DELIVERY

[0002] This application claims the priority to and benefit of Indian Patent Application No. 202441067976 filed on September 09, 2024 the disclosures of which are incorporated herein by reference.

[0003] FIELD OF THE INVENTION

[0004] The present invention relates to a microneedle patch for subcutaneous laser delivery. More particularly, the invention relates to biocompatible microneedle patch for subcutaneous laser delivery for cosmetic surgeries, preferably pigmented lesion or tattoo removal.

[0005] BACKGROUND OF THE INVENTION

[0006] There has been a long felt need for a treatment system and method for tattoos, for tattoo procedures, without the undesirable side effects. Though there is no universally accepted tattoo treatment. Laser phototherapy (photothermolysis) is perhaps the better treatment regimen available to date for tattoo lightening and removal.

[0007] The "whitening" or "whitening reaction" refers to any event or sequence of events that causes a negative therapeutic effect resulting from exposure of a treatment area to a light output. These events may include one or more chemical reactions and / or physical changes. One example of this negative effects of light therapies is that the laser induces immediate whitening reactions that are hypothesized to result from thermally induced cavitation bubble formation. Thus, bubbles presence reduces light therapy effectiveness.

[0008] With the recognition of laser treatment as a non-invasive surgical solution for the removal of subdermal pigmented lesions and accreted chromophores, the technology has rapidly evolved in the last few decades in terms of clinical efficiency and reach. It is now a globally standardized surgical procedure, available in many nations and is often the preferred treatment for removal of various pigmented lesions and tattoos. The technique is established on the principle of selective photothermolysis, wherein certain wavelengths of light is absorbed exclusively by the chromophore / pigments which then generates heat and successively disintegrates. The exact mechanism of photolytic disintegration is not elucidated till date, however, it is hypothesized to occur due to thermoacoustic phenomena (the pulsed laser induces successive expansion and contraction of pigment / chromophore clusters, which in turn contribute to its disintegration) and partially due to increased kinetic motion of clustered pigments / chromophores. The disintegrated particles will become less visible (cosmetic result is achieved at this stage; not considering potential scarring) and will eventually be cleared by the immune system.

[0009] One apparent limitation of this surgery is that the choice of laser (pulse rate and wavelength; higher pulse rate is generally preferred) is dependent on the pigment / chromophore, which entails that only homogenous clusters of pigments / chromophores can be broken down for a given monochromatic laser source. Further, from a surgical point of view, one cannot be certain of the absorption maxima for the given pigment / chromophore ensconced under the skin and therefore cannot select an optimal wavelength. A more crucial limitation is regarding the penetration of the laser per se. The epidermal layer attenuates most of the laser resulting into exponentially fall in intensity with increasing depth. Therefore, only longer wavelength lasers can penetrate deeper into the skin. Thus, it is difficult to efficiently disintegrate pigments / chromophores lying beneath the dermis (many of which naturally do). Hence, some surgical procedures require denuding of the epidermis using a CO2 laser, which despite engendering in impressive surgical outcomes also greatly raises the risk of post-surgical complications as well as the time and cost of the overall surgery in addition to the inconvenience and pain to the patient. Besides these limitations, a lot of heat is generated due to photothermolysis during the procedure which leads to scarring and minor tissue damage. The heat and pressure generated by the pigment / chromophore also damage neighboring cells and tissues. Finally, it is often the case that the desired cosmetic outcomes are only rarely attained and may require multiple rounds of laser surgery to achieve a less than perfect result.

[0010] US10322077B2 by Biochemics Inc, provides methods and formulations for removing a tattoo by using a cell disrupter in combination with a vasodilator, and optionally one or more of an osmotic modifying agent, a chelation agent, and an occlusive modifying agent, further include using one or more of an antibiotic, anesthetic, penetration enhancer, excipient, carrier and vehicle.

[0011] IN 202117003405 by Lightsense Israel Ltd., discloses the removal of unwanted skin pigmentation and tattoo ink that can remove multiple different colours using laser light of a single wavelength, with pulse width in the range of about 0.1-100 ps.

[0012] Thus, there is a need to develop better solution in cosmetic industry with an improved procedure for subcutaneous laser delivery without falling in intensity resulting into efficient therapeutic results, avoiding the use of additional costliest surgical procedures.

[0013] OBJECTS OF THE INVENTION

[0014] The primary object of the present invention is to provide a biocompatible microneedle patch for subcutaneous laser delivery.

[0015] Another object of the invention is to provide a biocompatible microneedle patch for subcutaneous laser delivery for skin whitening / lightening in cosmetic surgeries, preferably pigmented lesion or tattoo removal.

[0016] Another object of the invention is to provide a biocompatible microneedle patch for subcutaneous laser delivery offering efficient therapeutic results avoiding the use of additional surgical procedures.

[0017] SUMMARY OF THE INVENTION

[0018] Accordingly, the present invention discloses a microneedle patch for subcutaneous laser delivery.

[0019] In one aspect, the present invention discloses a microneedle patch for subcutaneous laser delivery for cosmetic surgeries e.g. laser based pigmented lesion removal and tattoo removal. In another aspect, the present invention discloses a microneedle patch which facilitate the delivery of laser to the deeper layers of the skin without falling in intensity.

[0020] In another aspect, the present invention discloses a microneedle patch providing efficient therapeutic results without requiring additional surgical procedures.

[0021] In another aspect, the present invention discloses a microneedle patch which makes the overall laser treatment cost effective.

[0022] Various aspects of the invention will now be described in detail with reference to the accompanying figures. Still other aspects, features, and advantages of the present invention are readily apparent from the entire description thereof, including the figures. Any subject matter described in the specification can be combined with any other subject matter in the specification to form a novel combination. The invention is also capable of other and different examples and aspects, and its several details can be modified in various respects, all without departing from the spirit and scope of the present invention. Accordingly, the drawings and descriptions are to be regarded as illustrative in nature, and not as restrictive. Furthermore, the terminology and phraseology used herein is solely used for descriptive purposes and should not be construed as limiting in scope.

[0023] BRIEF DESCRIPTION OF DRAWINGS

[0024] The drawings described herein are intended to provide a further understanding of the invention and are intended to be a part of the invention. However, the drawings as shown are representative for illustration and are non-limiting the scope of the invention. The drawings are described as below:

[0025] Figure: 1 illustrates a microneedle patch for subcutaneous laser delivery (FIG: 1A, & IB);

[0026] Figure: 2 illustrates functioning of microneedle patch for subcutaneous laser delivery (Fig: 2A, 2B, & 2C); Figure: 3 illustrates fabrication of microneedle patch for subcutaneous laser delivery (FIG. 3A-H); and

[0027] Figure: 4 illustrates flow chart of tattoo / pigmented lesions removal procedure.

[0028] DETAILED DESCRIPTION OF THE INVENTION

[0029] Various embodiments of the present disclosure will be described in detail with reference to the drawings, wherein like reference numerals represent like parts and assemblies throughout the several views. Reference to various embodiments does not limit the scope of the disclosure. Additionally, any examples set forth in this specification are not intended to be limiting and merely set forth some of the many possible embodiments for the present disclosure.

[0030] The present invention discloses a biocompatible microneedle patch

[0100] for subcutaneous laser delivery onto the skin in cosmetic surgeries, preferably pigmented lesion or tattoo removal.

[0031] Definitions: It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting. As used in this specification and the appended claims, the singular forms "a," "an" and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "microneedle" includes one or more such microneedles and the like.

[0032] Unless defined otherwise, all technical, scientific or other terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the invention pertains. Although other methods and materials similar, or equivalent, to those described herein can be used in the practice of the present invention, the preferred materials and methods are described herein.

[0033] In describing and claiming the present invention, the following terminology will be used in accordance with the definitions set out below. As used herein, the terms “microneedle patch” refers to a microneedle path subcutaneous laser delivery substantially as disclosed in the present invention.

[0034] As used herein, the terms “microneedle” refers to microneedles having penetrating length between 100 to 600 microns and the diameter at tip is ranging between 50 to 100 microns.

[0035] As used herein, the terms “subcutaneous” refers the deeper layers of the skin, preferably 1.65 mm to 25.20 mm inside from the outer layer of skin.

[0036] As used herein, the terms “laser” refers to light having wavelength between 300 nm to 1200 nm.

[0037] As used herein, the terms “biocompatible material” refers to synthetic materials which are compatible with biological system specifically with skin and devoid of cytotoxicity, genotoxicity, mutagenicity, carcinogenicity and immunogenicity.

[0038] The main embodiment of the present invention discloses a biocompatible microneedle patch

[0100] for subcutaneous laser delivery for skin whitening / lightening in cosmetic surgeries, preferably pigmented lesion or tattoo removal.

[0039] I. A MICRONEEDLE PATCH

[0100] FOR SUBCUTANEOUS LASER DELIVERY

[0040] The present invention discloses a microneedle patch

[0100] for subcutaneous laser delivery; particularly, a microneedle patch

[0100] for subcutaneous laser delivery for cosmetic surgeries e.g. laser based pigmented lesion removal and tattoo removal is discloses.

[0041] In another embodiment, the present invention discloses a microneedle patch

[0100] which facilitate the delivery of laser to the deeper layers of the skin without falling in intensity. In another embodiment, the present invention discloses a microneedle patch

[0100] which makes the overall laser treatment cost effective.

[0042] The present invention discloses a microneedle patch

[0100] for subcutaneous laser delivery. The microneedle patch

[0100] for subcutaneous laser delivery can be better understood with the help of the FIG.1A. The microneedle patch

[0100] for subcutaneous laser delivery disclosed in the present invention comprises: (a) a base layer

[0110] comprising a light entry side (LES)

[0111] and a contact side (CS)

[0112] ; (b) an microneedle array

[0120] comprising a plurality of microneedles (1201, 1202, 1203... 120n) embedded into the base layer

[0110] , wherein each microneedle comprises a light entry side (LES) (1211, 1212, 1213... 121n) and a light delivery side (LDS) (1221, 1222, 1223... 122n); (c) an convex lens array

[0130] comprising a plurality of lenses (1301, 1302, 1303... 130n); wherein the said lenses (1301, 1302, 1303... 130n) are arranged at the light entry side (LES) (1211, 1212, 1213... 121n) in such a way that the center of each lens (1301, 1302, 1303. . . 130n) aligns with the center of base of each microneedle (1201, 1202, 1203... 120n).

[0043] The base layer

[0110] is made up of any suitable biocompatible material. The biocompatible material is selected from poly urethanes or silicone. In one embodiment the base layer

[0110] is made up of poly urethanes. In another embodiment the base layer

[0110] is made up of silicone.

[0044] The base layer

[0110] is preferably flexible capable of withstanding the pressure while microneedles penetrating the human skin without fracturing. Flexibility allows the patch to snuggly fit onto the external body of the patient. There would not be need of any adhesive as the microneedles themselves are sufficient to hold the patch in place.

[0045] The base layer

[0110] is preferably optically transparent (allows passage of light of wavelength 300 nm to 1200 nm) allowing the laser light to directly interact with the pigments without loss in intensity. The base layer

[0110] is having thickness between 2-5 mm allowing convenient handling of the patch by the surgeon / professional prior to affixing it on the skin.

[0046] The length of the microneedles (1201, 1202, 1203... 120n) protruding from the contact side (CS)

[0112] is also ranging between 100 to 1000 microns. The melanoma pigment cells are usually located between the dermis and epidermis, and tattoo ink is usually deposited in the dermis, thus the exact length of the microneedles ( 1201, 1202, 1203. . . 120n) protruding from the contact side (CS)

[0112] will vary depending on the location of the skin; however, within the range between 100 to 1000 microns.

[0047] The diameter of the microneedles (1201, 1202, 1203... 120n) from the light entry side (LES) (1211, 1212, 1213... 121n) is ranging from 200 to 400 microns. The distance between each adjacent microneedle (1201, 1202, 1203... 120n) is around 100-500 microns (along the breadth and length of the patch).

[0048] As shown in FIG. IB, the microneedles (1201, 1202, 1203... 120n) are preferably concave tipped microneedles from the light delivery side (LDS) (1221, 1222, 1223. . . 122n). Concave tip allows the spread of light upon exiting the tip. The tips are on the contact side (CS)

[0112] of the base layer

[0110] patch which comes in contact with the human skin, the opposite face of the base layer

[0110] being the light entry side (LES)

[0111] ,

[0049] In one embodiment, the microneedles (1201, 1202, 1203... 120n) are dissolving tip microneedles (DTMN), wherein that penetrates the epidermis. After penetration, these dissolving tip microneedles (DTMN) become concave tipped post dissolution of the tip. The microneedles (1201, 1202, 1203. . . 120n) with dissolving tip is shown in Fig: 2B and 2C.

[0050] The lenses (1301, 1302, 1303... 130n) are convex lenses having diameter ranging from 200 to 400 microns. The lenses (1301, 1302, 1303... 130n) are arranged at the light entry side (LES) (1211, 1212, 1213... 121n) in such a way that the center of each lens (1301, 1302, 1303... 130n) aligns with the center of base of each microneedle ( 1201, 1202, 1203. . . 120n) in such a manner that the diameter of each lens will coincide with the base diameter of each microneedle. The lenses (1301, 1302, 1303. . . 130n) focus the light being impinged through the microneedle.

[0051] The microneedle patch

[0100] for subcutaneous laser delivery varies in the size from 1 square inch to 36 square inch.

[0052] In one embodiment, the microneedle patch is used with Perfluorodecalin (CioFis), to absorb the excess gases at the skin surface during the laser surgery which will improve the overall clinical outcome.

[0053] II. FUNCTIONING OF A MICRONEEDLE PATCH

[0100] FOR SUBCUTANEOUS LASER DELIVERY

[0054] The functioning of the microneedle patch

[0100] for subcutaneous laser delivery can be understood with the help of accompanying Figure: 2 (Fig: 2A, 2B and 2C).

[0055] Referring to Fig: 2 A, the microneedle patch

[0100] is affixed over the skin to be given cosmetic surgery. The microneedles (1201, 1202, 1203... 120n) penetrate the epidermis. When the laser is delivered, the laser is delivered to the deeper layer of the skin through the microneedles resulting into disintegration of the chromophore / pigments .

[0056] Referring to Fig: 2B and 2C, in Fig: 2B the microneedle patch

[0100] with dissolving tip microneedles (DTMN) is affixed over the skin to be given cosmetic surgery. The dissolving tip of these dissolving tip microneedles (DTMN) dissolved after penetration leaving concave tipped microneedles (1201, 1202, 1203... 120n) as shown in Fig: 2C.

[0057] III. FABRICATION OF A MICRONEEDLE PATCH

[0100] FOR SUBCUTANEOUS LASER DELIVERY

[0058] The microneedle patch

[0100] of the present invention can be fabricated with a micro-molding-based synthesis. The micro-molding synthesis is explained in Figure: 3 (FIG. 3A to 3H). FIG.3A depicts mold substrate for dissolving tip microneedles (DTMN). FIG.3B depicts pressing of dissolving tip microneedles (DTMN) mold on the substrate. FIG.3C depicts dissolving tip microneedles (DTMN) mold. FIG.3D depicts casting of dissolving substrate for formation of dissolving tip. FIG.3E depicts fabrication of dissolving tip. FIG.3F depicts casting of concave tip microneedle component (CTMC). FIG.3G depicts pressing of concave tip microneedle component (CTMC) mold. FIG.3H depicts fabricated dissolving tip microneedles (DTMN).

[0059] The microneedle patch

[0100] of the present invention can be also fabricated via micro-injection molding with the appropriate molds. And this case, it need not necessarily incorporate a dissolving tip.

[0060] The dimensions of dissolving tip microneedles (DTMN) and number of needles per cm2can be varied based on requirements. The length and density affect the penetration of microneedles, a length of 500-600 pm and 2000 needles per cm2have been experimentally demonstrated as a good balance between length and needle density. The concave tip microneedle component (CTMC) substrate can also be mixed with filler materials to increase the absorption of heat which will be generated during the surgery.

[0061] Testing:

[0062] Dissolving tip microneedles (DTMN) can be tested on cadavers and amputated parts which are subcutaneously impregnated with chromophores.

[0063] The present description is the best presently-contemplated product and process for carrying out the present invention. Various modifications to the preferred embodiment will be readily apparent to those skilled in the art and the generic principles of the present invention may be applied to other embodiments, and some features of the present invention may be used without the corresponding use of other features. Accordingly, the present invention is not intended to be limited to the embodiment shown but is to be accorded the widest cope consistent with the principles and features described herein.

Claims

im:

1. A biocompatible microneedle patch [100] comprising: a. a base layer [110]; b . a microneedle array [120]; c. a convex lens array [130] comprising a plurality of lenses (1301, 1302, 1303... 130n);2. The microneedle patch as claimed in claim 1, wherein the base layer [110] comprises a light entry side (LES) [111] and a contact side (CS) [112].

3. The microneedle patch as claimed in claim 1, wherein the microneedle array [120] comprising a plurality of microneedles (1201, 1202, 1203... 120n) embedded into the base layer [110].

4. The microneedle patch as claimed in claim 3, wherein each microneedle comprises a light entry side (LES) (1211, 1212, 1213... 121n) and a light delivery side (LDS) (1221, 1222, 1223... 122n).

5. The microneedle patch as claimed in claim 1, wherein the said lenses (1301, 1302, 1303... 130n) are arranged at the light entry side (LES) (1211, 1212, 1213... 121n).

6. The microneedle patch as claimed in claim 5, wherein center of each lens (1301, 1302, 1303... 130n) aligns with the center of base of each microneedles (1201, 1202, 1203... 120n).

7. The microneedle patch as claimed in claim 1, wherein the base layer [110] is made from a biocompatible material selected from poly urethanes or silicone.

8. The microneedle patch as claimed in claim 7, wherein the base layer [110] is made from poly urethanes.

9. The microneedle patch as claimed in claim 7, wherein the base layer [110] is made from silicone.

10. The microneedle patch as claimed in claim 1, wherein the base layer [110] is flexible and capable of withstanding the pressure while microneedles penetrating the human skin without fracturing.

11. The microneedle patch as claimed in claim 1, wherein the base layer [110] is optically transparent to allow the laser light to directly interact with the pigments without loss in intensity.

12. The microneedle patch as claimed in claim 11, wherein the optically transparent base layer [110] allows passage of light having wavelength between 300 nm to 1200 nm.

13. The microneedle patch as claimed in claim 1, wherein the thickness of the base layer [110] is between 2-5 mm allowing convenient handling of the patch by the surgeon / professional prior to affixing it on the skin.

14. The microneedle patch as claimed in claim 3, wherein the length of the microneedles (1201, 1202, 1203... 120n) protruding from the contact side (CS) [112] is between 100 to 1000 microns.

15. The microneedle patch as claimed in claim 3, wherein the diameter of the microneedles (1201, 1202, 1203... 120n) from the light entry side (LES) (1211, 1212, 1213... 12 ln) is between 200 to 400 microns.

16. The microneedle patch as claimed in claim 3, wherein the distance between each adjacent microneedle (1201, 1202, 1203... 120n) is around 100-500 microns along the breadth and length of the patch.

17. The microneedle patch as claimed in claim 3, wherein the microneedles (1201, 1202, 1203. . . 120n) are preferably concave tipped microneedles from the light delivery side (LDS) (1221, 1222, 1223... 122n).

18. The microneedle patch as claimed in claim 17, wherein the tips are on the contact side (CS) [112] of the base layer [110] patch which comes in contact with the human skin, the opposite face of the base layer [110] being the light entry side (LES) [111].

19. The microneedle patch as claimed in claim 1, wherein the microneedles (1201, 1202, 1203... 120n) are dissolving tip microneedles (DTMN).

20. The microneedle patch as claimed in claim 19, wherein after penetration, the dissolving tip microneedles (DTMN) become concave tipped post dissolution of the tip.

21. The microneedle patch as claimed in claim 1, wherein the convex lenses have diameter ranging from 200 to 400 microns.

22. The microneedle patch as claimed in claim 1, wherein the lenses (1301, 1302, 1303. . . 130n) are arranged at the light entry side (LES) (1211, 1212, 1213. . . 121n).

23. The microneedle patch as claimed in claim 22, wherein the center of each lens (1301, 1302, 1303... 130n) aligns with the center of base of each microneedle (1201, 1202, 1203... 120n) in such a manner that the diameter of each lens coincides with the base diameter of each microneedle.

24. The microneedle patch as claimed in claim 1, wherein the convex lenses (1301, 1302, 1303... 130n) focus the light being impinged through the microneedle.

25. The microneedle patch as claimed in claim 1, wherein, the microneedle patch is optionally used with Perfluorodecalin (CioFis), to absorb the excess gases at the skin surface during the laser surgery.

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