At the tip of a micro-needle: a "smart" bracelet will inject insulin into the body without pain

The development of scientists from St. Petersburg is equipped with an array of micro-needles created using 3D printing. Insulin is injected into the body by pressing a button once. Micron-sized needles pierce the stratum corneum of the skin, bringing the drug to the epidermis or the upper layer of the dermis, from where it penetrates unimpeded into the systemic bloodstream. The person will not feel pain, as the needles do not reach the nerve endings. In the future, such bracelets may find mass application as individual means for diabetes therapy, experts believe. Read more about the technology - in the material "Izvestia".

How does the bracelet works for diabetics

A scientific group from St. Petersburg State Electrotechnical University "LETI" (St. Petersburg State Electrotechnical University) is developing devices for emergency injection of insulin into the human body in diabetes. The team has already created a "smart" patch - a microelectronic device with an array of special micro-needles, a reservoir for the drug and a micropump to ensure its administration. At that time, to obtain the needles, engineers designed a special machine that allowed to obtain them by injection molding, but such technology did not allow to obtain an array with the required number of needles. Now scientists have been able to create a prototype of a more advanced wearable compact device.

- It is a bracelet with a microelectronic device - an array of hollow micro-needles, which was obtained by 3D printing. The main principle of its operation is to destroy the skin with micro-needles, which creates micron-sized channels through which the drug goes directly to the upper layer of the skin for further penetration into the systemic bloodstream. Thus, the development allows to ensure less invasiveness and the duration of the procedure without the participation of medical personnel, - said the project leader, researcher of the Center for Microtechnology and Diagnostics (CMID) of St. Petersburg State Technical University "LETI" Daria Adamovich Daria Adamovich.

To study the function of substance transfer through the channels of micro-needles, a special stand was developed, and the basic function of the micro-needle array - substance transfer through the channels under the action of controlled pressure - was tested.

As explained by the developers, the introduction of the drug (up to 4 ml) into the body is carried out by a single press on the button. Micron-sized needles pierce the stratum corneum of the skin, bringing the drug to the epidermis or the upper layer of the dermis, from where it freely penetrates into the systemic bloodstream. A person will not experience pain, as the needles do not reach the nerve endings. Damage to the skin is minimal, and healing occurs quite quickly, which compared to conventional injections reduces the risk of infection, and can also be used independently and ensures rapid penetration of the drug into the body.

How diabetes is treated

Hollow micro-needles provide the maximum rate of transfer of the substance - up to 2 ml/min. In the future, scientists want to modernize the device, which will include not only an array of hollow micro-needles, but also a hydrodynamic system with channels, a reservoir for the drug and a glucometer.

- The small-sized insulin pump would attach to a wristband, the fluid in which could be refreshed. Currently we are also considering the possibility of developing a design that will allow to administer insulin at a strictly defined time and in a given amount, - said the leading researcher of IC CMID SPbGETU "LETI" Ivan Konstantinovich Khmelnitsky.

To improve the quality of life of diabetes patients, various methods of insulin delivery are being developed, Natalia Yeremicheva, an endocrinologist at the Clinic of Infectious Diseases of the FBUN Central Research Institute of Epidemiology of Rospotrebnadzor, told Izvestia. Subcutaneous injections cause pain, discomfort, discomfort, and can also lead to undesirable consequences from incorrect insulin administration, so the emphasis on insulin delivery to the body is aimed at a minimally invasive, painless method.

- "Smart" bracelet is definitely suitable for patients with diabetes who, due to fear of injections, refuse to administer insulin, or, for example, there may be a need for urgent administration of insulin at some points. But still the main indicator of the patient's compensation can be called the correct calculation of the necessary amount of insulin and glucose control at certain times, - emphasized the endocrinologist.

Diabetes mellitus remains one of the most common and fastest growing non-communicable diseases. In 2022, WHO has set five global targets for diabetes control, one of which is to achieve stable glycemic control in 80% of patients, as more than half of patients do not receive timely treatment, Maria Salnikova, head of medical research at biotech startup studio Scanderm, a participant in the Healthnet STI market, told Izvestia.

- In this context, the wearable device for insulin administration developed at LETI St. Petersburg State Technical University meets the current needs of healthcare. Its key advantage is microinvasiveness, which ensures painlessness and safety when used independently," she noted.

Prospective integration with glucometer and automatic dosing will create an autonomous system of diabetes control, reducing the risks of hypo- and hyperglycemia, as well as other complications, the expert emphasized.