新型传感器有望利用唾液检测血糖

近日，科学家开发出一种针对糖尿病患者的新型传感器，这种新型传感器可以利用唾液而不是血液，来检测血糖水平。

Brown大学科学家们创造了新的传感器，成功地使用人工唾液测试其测量糖浓度的功效。新的传感器由光源、金属以及一个当暴露于血糖，会改变颜色的特殊酶组成。

众所周知，糖尿病患者需要通过刺破手指采血来检查血糖，并且每天需要重复多次。因此，研究人员正在寻找另一种测试血糖的可能性，结果发现唾液是可以用于测量血糖的另一种体液。

但是该传感器目前无法得到广泛使用，因为美国FDA批准过程将需要很长的时间，我们必须确认这个装置如何可以准确用于检测人类血糖，尤其对于那些大吃大喝的患者，因为这些患者唾液中含有大量物质，这很可能会污染测试样品，影响测试结果。

研究结果发表在Nanophotonics杂志上。新型传感器采用一种光源和金属表面，其中金属表面能干扰光击中（接触）样品的方向，光“读取”特异性酶如何对唾液存在的糖作出反应，以测量样品中糖的浓度。

研究人员利用人工唾液测试了该传感器，看看它如何工作（人工唾液没有实际唾液中的潜在混合物，例如口腔中食品或饮料会改变测试结果）。结果发现该传感器能够检测血糖水平，并且精确度很好。

Palmore说，下一步是使该设备便于携带，还需要利用真正的唾液测试传感器，同时找到便宜的光源。此外在测试唾液样品前，还需要某种冲洗剂洗漱测试者的口腔。比如漱口剂就可以去除口腔残留食物或其他可能影响血糖读数的污染物。 

详细英文报道：

A new type of sensor for people with diabetes is being developed to measure sugar levels in the body using saliva instead of blood, researchers report.

Scientists at Brown University in Providence, R.I., created the sensor and successfully tested it using artificial saliva. It uses light, metal and a special enzyme that changes color when exposed to blood sugar.

"Everybody knows that diabetics have to prick their fingers to draw blood to check their blood sugar and then respond to that information. And they have to do that multiple times a day," said study co-author Tayhas Palmore, a professor of engineering, chemistry and medical science at Brown.

"We're looking for another possibility, and realized that saliva is another bodily fluid that could be measured," Palmore said.

This idea is a welcome one, said Dr. Joel Zonszein, director of the Clinical Diabetes Center at Montefiore Medical Center in New York City. "People are always trying to come up with new ideas of how to measure blood sugar without pricking the fingers."

The sensor won't be available anytime soon, however. "The process of [U.S. Food and Drug Administration] approval will take a long time, and we have to see how accurate this device is in humans, especially humans who are eating and drinking, which will possibly contaminate the sample," Zonszein said.

Findings from the study, which received funding from the National Science Foundation, were published recently in the journal Nanophotonics.

To check their blood sugar—or glucose—levels, people with diabetes—especially those who need insulin—must prick one of their fingers to draw a drop of blood. The blood is put on a test strip that goes into a blood sugar meter. They are supposed to repeat this procedure four times a day, according to the American Diabetes Association.

The results of the blood sugar tests guide treatment, with diabetes patients often adjusting medication or insulin levels based on the test reading to maintain acceptable glucose levels.

The Brown researchers realized that saliva also contains glucose, though in much lower quantities.

The new device uses light and a metal surface that interferes with the way light hits a sample, Palmore said. The light "reads" how a special enzyme reacts to the presence of sugar in saliva to measure the concentration of sugar in a sample.

The researchers tested the sensor on artificial saliva to see how well it works without the potential complications found in real saliva. For example, food or drinks could alter the results. The sensor was able to detect sugar levels with high accuracy, they said.

Palmore said the next step is to make the device portable, hopefully small enough to fit in your hand. They also need to test it on real saliva, and find inexpensive light sources. Palmore said the researchers are also working on ways to measure insulin levels in the body.

Some sort of rinse for use before testing a saliva sample is also needed. A mouthwash could remove food or other contaminants that might affect the glucose reading, according to Palmore.

"Just because there is an established way of measuring blood sugar, doesn't mean it's the only way," said Palmore. "This is a priority area of research for many people. There's some hope that you may not have to prick yourself every couple of hours."

Zonszein added that the idea of searching for alternatives is a good one. "But to apply that from the lab to human clinical trials is still very far away," he said.