DESC:
[0022] In the following detailed description, reference is made to the accompanying drawings that form a part hereof, and in which the specific embodiments that may be practiced is shown by way of illustration. These embodiments are described in sufficient detail to enable those skilled in the art to practice the embodiments and it is to be understood that the logical, mechanical and other changes may be made without departing from the scope of the embodiments. The following detailed description is therefore not to be taken in a limiting sense.
[0023] The present invention discloses a device and method of trans-dermal vaccine delivery using a miniature detonation-driven shock tube device wherein shockwaves generated by ignition of oxyhydrogen mixture (hydrogen and oxygen gases in stoichiometric ratio) to create high velocity liquid jets which is sufficient to penetrate the human skin without any physical damage. The oxyhydrogen driven shock tube is optimized for efficiently delivering vaccines in the intra dermal region in vivo. The oxyhydrogen mixture is generated in-situ during the operation of the device and the method used for shockwave generation is carbon-free, green and gives water as the byproduct.

[0024] The most commonly used needle and syringe method for drug administration has come under scrutiny in the recent decades because of factors like needle contamination, requirement for safe disposal of used needles, waste accumulation, accidental needle-stick, pain during usage and needle phobia. Therefore, many new alternative non-invasive means of drug delivery have been developed, which mainly use oral, pulmonary, nasal, buccal or transdermal routes of administration.
[0025] Among these, the drug transport through human skin proves to be more advantageous compared to the other routes due to the ease of administration, immunosurveillance functions and easy accessibility. Liquid-jet injectors, powder immunization and microneedles are some of the budding technologies for transdermal delivery of drugs. Many methods to improve the efficiency of transdermal therapeutic systems by enhancing the driving force to increase the rate of drug transport have also been suggested. However, these techniques face major challenges due to the selectively permeable nature of the human skin and its ability to restrict molecular transport.
[0026] The shockwave-assisted drug delivery device described in the present work surpasses the present-day needle and syringe technique of injections as it is needle-free, painless and eliminates the need for non-biodegradable waste disposal, avoiding the risk of disease transmission and there is no damage to cell tissues around the region of injection. In addition to these advantages, the proposed device uses in situ generation of oxyhydrogen mixture which avoids storage and mixing of detonable gases. The device uses minimal consumables, produces water as a main by-product during usage and is safe as well as reproducible. All these advantages coupled with the innovative design make it a unique and first-of-its-kind device. The device was optimized to deliver vaccines in the transdermal region which lies at a depth of~100 µm from the skin surface.
[0027] In the present work, we have developed a shockwave-assisted vaccine delivery device and method that can generate high velocity jets through the detonation of in situ generated oxyhydrogen mixture (stoichiometric mixture of hydrogen and oxygen gases in the ratio 2:1). The ability of the proposed device to produce shockwaves of required strength in a safe, clean and reproducible manner opens up new opportunities for shockwave-assisted biomedical research. This device demonstrates the potential for localized drug delivery using shockwaves.
[0028] The device comprises of two main components. The first is an oxy hydrogen generator station. This is a table top system that generates the oxyhydrogen miniature in situ. The second is a miniature handheld device which is used to administer the drug to the patient. Through alkaline electrolysis, the oxyhydrogen generator produces about 2.5 bar of oxy hydrogen mixture during each operation of the device. The oxyhydrogen mixture is tapped from the outlet wherein the miniature handheld device is a shock tube with an internal diameter 6 mm and comprises of two sections – a driver section of length 200mm and driven section of length 70mm at least. A tracing paper (of 95 GSM at least) is used as diaphragm to separate the driver section and driven section of the shock tube.
[0029] The driver section of the shock tube is filled with at least 2.5 bar of oxyhydrogen mixture and the mixture is detonated. This ruptures the diaphragm and a strong shockwave is created in the driven section of the shock tube. The vaccine is accommodated in a stainless steel sterile cavity of diameter at least 6mm and depth of at least 5mm. The bottom of the cavity has a 300µm diameter hole to allow vaccine to be ejected in the form of a jet on shockwave impact. The drug is held back initially in the cavity by surface tension. The direct impact of the shock wave followed by the products of detonation on the drug sample leads to issues of contamination. To avoid this, a suitable barrier is chosen for good energy transfer and to prevent the detonation products from impacting the drug. A silicone rubber membrane has been used between the shock tube and the drug.
[0030] FIG.1 illustrates the schematic view of the oxyhydrogen generator according to an embodiment of the present invention. According to the embodiment, the oxyhydrogen generator comprises of the electrolysis unit 101, the buffer chamber 102 and the recirculation pipes 103. The electrolysis unit comprises of at least four neutral plates which are stacked between two sets of electrode plate. This set of 6 plates constitutes one electrolysis cell. Similarly, 6 cells are stacked and connected in series as shown in the figure 1. Electrode plates and neutral plates are made out of stainless steel plates. An equal spacing of ~2 mmis maintained between the electrodes and the neutral plates by using electrical insulators. About 7M potassium hydroxide solution (400 g of KOH in 1 l of distilled water) is used as electrolyte. The chemical reactions at the anode and the cathode of the electrolysis unit during electrolysis enable to generate the hydrogen and the oxygen gases at the cathode and anode points. Since both these electrodes are confined to a single chamber, the hydrogen and oxygen gases get collected above the electrolyte solution in the electrolysis unit.
[0031] FIG.2 illustrates the schematic view of the miniature handheld device according to an embodiment of the present invention. According to the embodiment, the shockwave-based needle-free and painless drug injector device comprises of two main components. The first is an oxy hydrogen generator station. This is a table top system that generates the oxyhydrogen miniature in situ. The second is a miniature handheld device which is used to administer the drug to the patient. Through alkaline electrolysis, the oxyhydrogen generator produces about 2.5 bar of oxy hydrogen mixture during each operation of the device. The oxyhydrogen mixture is tapped from the outlet wherein the miniature handheld device is a shock tube with an internal diameter 6 mm and comprises of two sections – a driver section 202 of length 200mm and driven section 201 of length 70mm at least. A tracing paper (of 95 GSM at least) is used as diaphragm to separate the driver section 202 and driven section 201 of the shock tube.
[0032] The driver section 201 of the shock tube is filled with at least 2.5 bar of oxyhydrogen mixture and the mixture is detonated. This ruptures the diaphragm and a strong shockwave is created in the driven section 202 of the shock tube. The vaccine is accommodated in a stainless steel sterile cavity 207 of diameter at least 6mm and depth of at least 5mm. The bottom of the cavity has a 300µm diameter hole 208 to allow vaccine to be ejected in the form of a jet on shockwave impact. The drug is held back initially in the cavity by surface tension. The direct impact of the shock wave followed by the products of detonation on the drug sample leads to issues of contamination. To avoid this, a suitable barrier is chosen for good energy transfer and to prevent the detonation products from impacting the drug. A silicone rubber membrane 206 has been used between the shock tube and the drug.
[0033] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. ,CLAIMS:WE CLAIM:

1. A shockwave-assisted vaccine delivery device that is capable of generating shockwaves for trans-dermal vaccine delivery using a miniature detonation-driven shock tube device, the device comprising:
a in situ oxyhydrogen generator apparatus,
a driver section,
a driven section,
a diaphragm station;
a battery unit;
a detonation initiator;
a silicon rubber membrane attached over the driven section;
a cavity in the silicon rubber membrane to hold the drug; and
at least 300 µm diameter hole placed above the cavity.
wherein, the generated oxyhydrogen mixture from the in situ oxyhydrogen apparatus is tapped from the outlet situated on the oxyhydrogen generator and fed into the miniature handheld shockwave-assisted trans-dermal vaccine delivery device in which the driver section of the shock tube is filled with at least 2.5 bar of oxyhydrogen mixture and the mixture is detonated using a battery and a detonation initiator which then ruptures the diaphragm and a strong shockwave is created in the driven section of the shock tube, the shock waves energy which then is transferred to the silicone rubber membrane provided over the handheld shockwave-assisted trans-dermal vaccine delivery device and the resultant shockwave is further provided to the cavity in the silicon rubber membrane which holds the drug that is to be administered to patient through the 300µm diameter hole placed above the cavity.

2. The shockwave-assisted trans-dermal vaccine delivery device according to claim 1, wherein shockwaves generated by ignition of oxyhydrogen mixture (hydrogen and oxygen gases in stoichiometric ratio) creates high velocity liquid jets which is sufficient to penetrate the human skin without any physical damage.
3. The shockwave-assisted trans-dermal vaccine delivery device according to claim 1, wherein the shockwave-assisted vaccine delivery device can generate high velocity jets through the detonation of in situ generated oxyhydrogen mixture (stoichiometric mixture of hydrogen and oxygen gases in the ratio 2:1).
4. The shockwave-assisted trans-dermal vaccine delivery device according to claim 1, wherein the vaccine is accommodated in a stainless steel sterile cavity of diameter at least 6mm and depth of at least 5mm.
5. The shockwave-assisted trans-dermal vaccine delivery device according to claim 1, wherein the bottom of the cavity has at least a 300µm diameter hole is allowed the vaccine to be ejected in the form of a jet upon the shockwave impact.